+----------------+ | NONMEASUREMENT | | SENSITIVE | +----------------+ MIL-R-28002A 30 November 1990 ---------------- SUPERSEDING MIL-R-28002 20 December 1988 MILITARY SPECIFICATION RASTER GRAPHICS REPRESENTATION IN BINARY FORMAT, REQUIREMENTS FOR This specification is approved for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope. This specification identifies the requirements to be met when raster graphics data represented in digital, binary format are delivered to the Government. Type II of this specification is a delimitation of the NIST ODA Raster DAP to suit Government applications. (See Appendix A.) 1.2 Classification. The digital representation of raster graphics data is one of the following types as specified by the contract or other form of agreement: Type I - Untiled Raster Graphics Data (Default Mode) Type II - Tiled/Untiled Raster Graphics Data +------------------------------------------------------------+ | Beneficial comments (recommendations, additions, | | deletions) and any pertinent data which may be used in | | improving this document shall be addressed to: | | Director, CALS Policy Office, OASD(P&L)WSIG Pentagon, | | Room 2B322, Washington, DC 20301, by using the self- | | addressed Standardization Document Approval Proposal (DD | | Form 1426) appearing at the end of this document or by | +------------------------------------------------------------+ AMSC N/A AREA ILSS DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. MIL-R-28002A 2. APPLICABLE DOCUMENTS 2.1 Government documents. 2.1.1 Specifications and standards. The following specifications and standards form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those listed in the issue of the Department of Defense Index of Specifications and Standards (DODISS) and supplement thereto, cited in the solicitation. (See 6.2.) STANDARDS FEDERAL FIPS PUB 150 - Telecommunications: Facsimile Coding Schemes and Coding Control Functions for Group 4 Facsimile Apparatus FIPS PUB 157 - Guideline for Quality Control of Image Scanners MILITARY MIL-STD-1840 - Automated Interchange of Technical Information (Copies of the referenced military standards are available from the Standardization Documents Ordering Desk, Building 4D, 700 Robbins Avenue, Philadelphia, PA 19111-5094. For specific acquisition functions, the current revisions of these documents should be obtained from the contracting activity.) (Copies of the Federal Information Processing Standards (FIPS) are available to Department of Defense activities from the Standardization Documents Ordering Desk, Building 4D, 700 Robbins Avenue, Philadelphia, PA 19111-5094. Others must request copies of FIPS from the National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161-2171. -2- MIL-R-28002A 2.2 Non-Government publications. The following documents form a part of this document to the extent specified herein. Unless otherwise specified, the issues of the documents which are DOD adopted are those listed in the issue of the DODISS cited in the solicitation. Unless otherwise specified, the issues of documents not listed in the DODISS are the issues of the documents cited in the solicitation. (See 6.2.) AMERICAN NATIONAL STANDARDS INSTITUTE ANSI Y14.1 - American National Standard, Drawing Sheet Size and Format (Application for this document should be addressed to ASME, United Engineering Center, 345 E. 47th Street, New York, NY, 10017) 2.3 Order of precedence. In the event of a conflict between the text of this document and the references cited herein, the text of this document shall take precedence. Nothing in this document, however, shall supersede applicable laws and regulations unless a specific exemption has been obtained. -3- MIL-R-28002A 3. REQUIREMENTS 3.1 General requirements. All digital raster graphics files complying with this specification shall conform to one of the two binary formats defined in this specification. Type I raster graphics binary format consists of Group 4 encoding as defined in FIPS PUB 150 (CCITT Recommendation T.6). Type II raster graphics binary format consists of ASN.1 and CCITT Recommendation T.6 encoding as specified by the document description presented in the NIST ODA Raster Document Application Profile (Appendix A). The type of raster graphics data, Type I or Type II, shall be specified in the contract. (See 6.2.1.) 3.1.1 Raster data file header records. As specified in MIL-STD-1840, files of Type I or Type II raster binary data shall begin with a data block containing header records that characterize the image encoded by the raster data. Of these header records, the following selected records shall have the indicated permissible values. 3.1.1.1 Raster data type. The permissible values for raster data type shall be '1' or '2'. This value shall be '1' to indicate Type I raster graphics data, or '2' to indicate Type II raster graphics data. This corresponds to MIL-STD-1840 header record 'ntype'. 3.1.1.2 Raster image orientation. The permissible values for the pel path direction shall be '0', '90', '180' or '270'. The permissible values for the line progression direction shall be '90' or '270'. (See 6.3.9.) This corresponds to MIL-STD-1840 header record 'rorient'. The values for pel path direction and line progression direction written to the file shall reflect the proper viewing orientation of each image. If so specified in the contract document, the contractor shall be required to perform rotation where necessary to achieve proper viewing orientation with pel path direction set to 0 and line progression direction set to 270. (See 6.2, 6.3.9, and Appendix A.) -4- MIL-R-28002A 3.1.1.3 Raster image pel count. Pel count shall be used to identify the dimensions of the original image in a coordinate system defined by the pel path and line progression directions. The dimensions shall be a set of two positive integers (see 3.1.2.1). This corresponds to MIL-STD-1840 header record 'rpelcnt'. As a guide, the dimensions for standard size technical documents and large format drawings are presented in section 6.3.2. If the minimal overscanning shown in section 6.3.2 is not sufficient to meet a specific contract requirement, the overscanning size shall be specified in the contract document. Otherwise, the drawing scan sizes listed in 6.3.2 are recommended. (See 6.2.1.) 3.1.1.4 Raster image pel density. Pel density shall be used to describe the number of samples per unit distance taken to create the raster image. This corresponds to MIL-STD-1840 header record 'rdensity'. Unless otherwise specified in the contract document, the pel density for raster images within technical documentation shall be 300 pels per inch. Unless otherwise specified in the contract document, the pel density for raster images representing large format engineering drawings shall be 200 pels per inch. (See 6.2.1 and 6.3.10.) 3.1.2 Raster binary data. As specified in MIL-STD-1840, Type I and Type II raster binary data shall be contained in data blocks that follow the header record data block. 3.1.2.1 Byte (octet) boundaries. An encoding program exporting documents from a system for interchange shall produce documents with a pel line dimension which is a multiple of eight pels. If so specified in the contract document, decoding systems may be required to be able to import documents which have arbitrary dimensions from other, non-MIL-R-28002A compliant systems. (See 6.2.1.) 3.1.2.2 Definitions of one and zero in bitmap data. A bitmap image or tile shall represent the "information" in a document by one bits and the "background" by zero bits. (See 6.3.12.) 3.1.2.3 Bit ordering. The bit ordering of most significant bit (MSB) to least significant bit (LSB) (the "down" ordering) shall be used for both compressed and bitmap data. If so specified in the contract document, the bit ordering of LSB to MSB for compressed data may instead be required for Type II files. (See 6.3.5 and 6.2.) 3.1.2.4 Prohibition on Recommendation T.6 escape option. The uncompressed escape option defined in FIPS PUB 150 (CCITT Recommendation T.6) shall not be used. -5- MIL-R-28002A 3.1.3 First article. When specified (see 6.2.3), a sample system and set of raster data files shall be subjected to first article inspection (see 6.2.3) in accordance with 4.3. 3.2 Specific requirements for Type II raster binary data. When Type II raster binary data files are specified (see 6.2.1), they shall be prepared in accordance with Appendix A and this section. This section further delimits the options supported by the NIST ODA Raster DAP of Appendix A to ensure unambiguous interchange to and from Government raster data systems. 3.2.1 Untiled/tiled Type II. If the Type II raster graphics data is to be specifically limited only to tiled or only to untiled data, the contract document shall specify "Type II tiled" or "Type II untiled." If the contract document specifies "Type II untiled," each file shall have a layout architecture in which each image has a single, undifferentiated block of raster data. (See 6.3.7 and 6.2.2.) 3.2.2 Tile index. If so specified in the contract document, the tile index option in the "Application-comments" attribute of the basic page layout object in Appendix A shall be included in each Type II tiled raster file. (See 6.2.2 and 6.3.15.) 3.2.3 Tile orientation. All tiles of a tiled raster image shall have the same orientation. 3.2.4 Tile ordering. Tiles of a tiled raster image shall occur in the file in pel path, line progression order. 3.2.5 Tile size. The size of all tiles of a tiled raster image shall be as specified in Appendix A. 3.2.6 Null tiles. Null tiles in a tiled raster image shall be indicated by use of the "Tile-type" attribute discussed in Appendix A. 3.2.7 Padding of partially imaged tiles. Decoding systems shall expect extraneous data in the unimaged portions of the tiles around the periphery of the document and guard against its presentation. When specified (see 6.2.2), encoding systems shall be required to set to background all such unimaged pels. (See 6.3.8.) -6- MIL-R-28002A 3.2.8 Minimizing file size. For tiled files, if so specified in the contract document (see 6.2.2), only tiles which (had they been compressed) would have compressed negatively shall be delivered in bitmap form. For untiled files, if so specified in the contract document (see 6.2.2), only images which (had they been compressed) would have compressed negatively shall be delivered in bitmap form. (See 6.3.14.) 3.2.9 Multiple pages. If a multiple page convention is specified in the contract (see 6.2.2), and a full-size and scaled-down image are included as separate basic pages within the same Type II document, the former shall occur first in the file. (See 6.3.6.) -7- MIL-R-28002A 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for inspection. Unless otherwise specified in the contract or purchase order, the contractor is responsible for the performance of all inspection requirements examinations and tests as specified herein. Except as otherwise specified in the contract or purchase order, the contractor may use his own or any other facilities suitable for the performance of the inspection requirements specified herein, unless disapproved by the Government. The Government reserves the right to perform any of the inspections set forth in the specification where such inspections are deemed necessary to assure that supplies and services conform to prescribed requirements. 4.1.1 Responsibility for compliance. All items shall meet all requirements of sections 3 and 5. The inspection set forth in this specification shall become a part of the contractor's overall inspection system or quality program. The absence of any inspection requirements in the specification shall not relieve the contractor of the responsibility of ensuring that all products or supplies submitted to the Government for acceptance comply with all requirements of the contract. Sampling inspection, as part of manufacturing operations, is an acceptable practice to ascertain conformance to requirements, however, this does not authorize submission of known defective material, either indicated or actual, nor does it commit the Government to accepting defective material. 4.2 Classification of inspections. The inspection requirements specified herein are classified as follows: a) First article inspection. (See 4.3.) b) Quality conformance inspection. (See 4.4.) 4.3 First article inspection. First article test procedures shall require that appropriate test data shall be scanned and encoded in accordance with this specification. These raster files shall be decoded and rendered on a reference system that complies with this specification. The contract should identify either the destination system that will eventually receive and store the raster files, or an alternative reference system, such as the CALS Test Network raster test platform (see 6.2.3). Identification of the same system for both encoding and decoding will permit evaluation of image quality, but will not permit evaluation of the proper compression or (in the case of Type II files) document architecture encoding. Test data shall be selected to rigorously exercise all attributes, values, and options. (For Type II data, the options are those found in Appendix A and are further -8- MIL-R-28002A delimited in Section 3.) Further, the test data shall contain all image sizes and degrees of complexity that will be delivered in accordance with this specification. In addition, the Government may require inclusion of Government-furnished test charts or images with diverse image content. The images shall be visually inspected to ensure that all attributes, non-basic values, basic values, permissible and default values conform to Type I or Type II formats, as specified. Insofar as possible, inspection and analysis procedures shall be automated with appropriate computer programs that report analysis and inspection results. The visual inspection shall also compare the image reproduced on the reference system to the original document to determine that the registration, linearity, alignment, coverage, aspect ratio, and scale are identical to the original to the degree discernable by the human eye. The reproduced image should be analyzed to ensure that the image is legible and in focus, and that the apparent contrast or threshold of the scanned image retained all lines that were clearly visible on the original without loss of continuity, without blacking-out cross-hatched or patterned areas and that the reproduction retained a balance of foreground and background in proportion to the contrast of the original. 4.4 Quality conformance inspection. On a reference system, the digital file shall be formatted and displayed on a CRT, or printed on a printer. If first article testing has not been performed on the encoding system, the images shall be visually inspected to ensure that all attributes, non-basic values, basic values, permissible and default values conform to contract requirements. If less than 100 percent inspection is performed, the digital data sample should contain all image sizes and the range of image content complexity of the entire lot of data. The images shall be visually inspected and compared to the original to ensure that all text is legible, that lines which were readily discernable on the original are present and unbroken, and that lines and patterns appear sharp, without fuzziness, smearing, or other indications of lack of focus. The visual inspection shall also compare the image reproduced on the reference system to determine that the registration, linearity, alignment, coverage, aspect ratio, and scale are identical to the original to the extent discernable by the human eye. 4.4.1 Verification of proper viewing orientation. Visual inspection shall verify that the pel path direction and line progression direction values found in each file correctly describe the proper viewing orientation of the data in the file. (See 3.1.1.2 and 6.3.9.) -9- MIL-R-28002A 4.4.2 Verification of rotation to proper viewing orientation. When required (see 3.1.1.2), visual inspection shall verify that with a pel path direction of 0 and a line progression direction of 270, the image appears in the proper viewing orientation. -10- MIL-R-28002A 5. PACKAGING Packaging of raster graphics data files shall be in accordance with the requirements of MIL-STD-1840. -11- MIL-R-28002A 6. NOTES 6.1 Intended use. This specification is intended to be used by contracting agencies of the Department of Defense in the procurement of raster graphics data and raster graphics applications. The specification presents raster graphics requirements which are applicable to interchange of raster encoded technical document pages, foldout illustrations, and large format engineering drawings. Raster graphics representation specified herein consists of two types. Type I raster graphics data has a simple file format with no document architecture and is untiled; i.e., it is represented by a single compressed data entity. Type II raster graphics data has a document architecture conforming to the NIST ODA Raster DAP (Appendix A). Type II data may be tiled or untiled as specified in the contract document. Type I raster graphics requirements are intended to be used in procuring data for systems that only use untiled raster graphics representations. Examples of such systems include typical technical documentation systems and DSREDS/EDCARS used by the Army and Air Force. Type II raster graphics requirements are intended to be used in procuring data for systems that need the flexibility to use tiled or a mixture of tiled and untiled raster graphics representations. Tiled representations are best applied in systems handling large format drawings or illustrations typically associated with engineering design. The subdivision of a drawing into tiles permits use of only those portions of an image required at a given time by the application. This can result in reduced requirements for workstation memory and workstation display area. In addition, tiling permits compression and decompression activities to be performed in parallel upon the drawing tiles. Type II provides for untiled raster graphics for images considered too small to require tiling, i.e., A-size or smaller. The following sections provide additional information concerning tiled and untiled raster graphics standardization. -12- MIL-R-28002A 6.1.1 Use of document architecture for Type II raster graphics. It is the intent of this specification to use existing and emerging standards as the basis for implementation. Formats presented for Type II data use such standards. This ensures that raster graphics specification efforts are within the mainstream of evolving raster imaging standards and promotes interoperability with other raster graphics formats used in the office document architecture standard. It is the intent of this specification to use new mechanisms or objects only where existing work cannot reasonably accommodate specification needs. 6.1.2 Type II raster graphics presentation and content attributes. Appendix A presents the specific limits and defaults for each of the document architecture presentation and content attributes used to interchange Type II raster graphics data. 6.1.3 Restriction to Group 4 compression. This specification exclusively requires Group 4 compression for Type I and Type II raster graphics encoding with a bitmap option for Type II encoding. Group 3 compression is specifically not supported. The uncompressed escape option defined in FIPS PUB 150 is not supported. For tiled raster graphics the ability to intersperse compressed and bitmap tiles as described by the "Tile-types" attribute in Appendix A meets several user requirements for tiled raster graphics content. A system or peripheral which must meet a given throughput requirement can selectively choose to leave uncompressed those tiles which do not compress in a specified amount of time. Similarly, this ability permits an upper bound to file size by using bitmap encoding for those tiles which (had they been compressed) would have compressed negatively. Both these requirements arise from the need to predict the behavior of an essentially statistical encoding technique. -13- MIL-R-28002A 6.2 Ordering data. The contract or other form of agreement should specify several items as indicated in the following subsections: 6.2.1 Fundamental ordering data. The following information must be included in any contract: a) Title, number, and date of this specification. b) The type of raster graphics data being procured as Type I or Type II. (See 3.1.) c) The delivery medium to be used. (See 5.) d) Proper viewing orientation. (See 3.1.1.2.) e) The raster image pel density. (See 3.1.1.4.) f) Overscanning. (See 3.1.1.3.) g) Bit ordering. (See 3.1.2.3.) h) Byte boundaries. (See 3.1.2.1.) 6.2.2 Additional ordering data for Type II procurements. The following items should be included if they are needed by the contract: a) Minimal file size option. (See 3.2.8.) b) Multiple page conventions. (See 3.2.9.) c) Padding of partially imaged tiles. (See 3.2.7.) d) Interchange of untiled/tiled Type II. (See 3.2.1.) e) Tile index. (See 3.2.2.) -14- MIL-R-28002A 6.2.3 First article. When first article inspection is required, the contracting officer should provide specific guidance to offerors whether the item should be a preproduction sample, a first article sample, a first production item, a sample selected from the first production items, or a standard production item from the contractor's current inventory, and the number of items to be tested. The contracting officer should also include specific instructions in acquisition documents regarding arrangements for examinations, approval of first article test results, and disposition of first articles. Invitations for bids should provide that the Government reserves the right to waive the requirement for samples for first article inspection to those bidders offering a product which has been previously acquired or tested by the Government, and that bidders offering such products, who wish to rely on such production or test, must furnish evidence with the bid that prior Government approval is presently appropriate for the pending contract. Bidders should not submit alternate bids unless specifically requested to do so in the solicitation. The contract must specify a reference system for first article test. (See 4.3.) -15- MIL-R-28002A 6.3 Data Requirements. 6.3.1 File size and efficiency considerations. Files containing large format drawings or illustrations in raster graphics form are relatively large. After Group 4 compression, E-sized drawings have a file size of approximately one-half of a megabyte for a moderately detailed drawing. For tiled raster graphics files, a tile index permits direct access to image tiles contained in the content stream. The format of this index is described in Appendix A. The tile index is only supported by tiled raster graphics applications and is placed in the "Application-comments" attribute associated with the layout object of the tiled raster graphics content. The index is optional in the NIST ODA Raster DAP (Appendix A) because it is possible for a receiving application to reconstruct a tile index from an imported file. 6.3.2 Sizes for engineering drawings. The drawing sizes, A through K, specified by ANSI Y14.1 and metric drawing sizes, A4 through A0, are summarized in the following tables. Shown are the nominal number of pels per line and the nominal number of lines. These values are for the default pel density for large format engineering drawings of 200 pels per inch. The numbers listed below are minimal, sufficient only to provide for byte alignment of the pels at the end of each bitmap line. 200 pels per line and 200 lines of total overscan would provide a recommended nominal one inch overscan without loss of byte alignment. This is not shown added into the numbers below, but would be consistent with current industry practice. Particular requirements associated with overscanning should be identified and specified in the contract document to allow extra white space at the margins, if needed. North American Drawing Sizes Drawing WxL(max) Pels Number Size (inches) Per Line of Lines A 8.5x11 1704 2200 B 11x17 2200 3400 C 17x22 3400 4400 D 22x34 4400 6800 E 34x44 6800 8800 F 28x40 5600 8000 G 11x90 2200 18000 H 28x143 5600 28600 J 34x176 6800 35200 K 40x143 8000 28600 Legal 8.5x14 1704 2800 -16- MIL-R-28002A Metric Drawing Sizes Drawing WxL(max) Pels Number Size (mm) Per Line of Lines A4 210x297 1656 2344 A3 297x420 2344 3312 A2 420x594 3312 4680 A1 594x841 4680 6624 A0 841x1188 6624 9360 6.3.3 Generation of raster data by scanning. Raster data for either technical publication or product definition materials may be generated by scanning source document sheets or pages in accordance with this specification. Scanning is performed in a line-by-line sequence from left to right, beginning at the leading edge of a page as it is fed into the scanner, and at a standard pel spacing selected to preserve the smallest detail (minimum line pair spacing) represented in the source material. Note that the image orientation may be such that the top of the image does not correspond to the leading edge of the scanned page. This scan-produced raster data is initially stored in intermediate, digital form as a binary bitmap such that respective ones and zeros reflect the black and white physical picture elements of the scanned image. In this intermediate or expanded form, raster scan data may be processed for enhancement or editing, or directly reproduced by an appropriate display or printing device. The relationship between the orientation of scanning and the orientation of image display must be accurately specified in the raster graphics presentation attributes. The relationship between the pel path and line progression attributes for typical images are shown in Figure 1 for portrait pages and in Figure 2 for landscape pages. 6.3.4 Additional data processing conditions. This specification defines the data formats required to describe a single page or sheet of Type I or Type II raster graphics content. Issues related to database management such as document information, aperture card Hollerith code, document and page relationships, sheets, revisions, and multiple aperture card frames are not considered in this specification. If such data is required as a deliverable, the procurement contract should specify the content and format of such data. -17- MIL-R-28002A 6.3.5 Note on bit ordering. While this specification calls for the bit ordering of most significant bit (MSB) to least significant bit (LSB)--the "down" direction--for both compressed and bitmap data, the proper ordering of bits within bytes (octets) is a subject of industry-wide dispute. The traditional method in facsimile equipment for compressed data is to pack code bits into bytes in "up" fashion, that is, LSB to MSB. The most widespread method used in sending bitmapped (uncompressed) data to computer display adapters is with a "down" ordering (MSB to LSB). It is conceivable that ISO will rule for ODA that these two differing techniques be used: one for instances of compressed data, and the other for instances of bitmap data. This means that both orderings could occur among tiles of the same file. In light of all this uncertainty, it is recommended that systems decoding Type II files be prepared to handle both bit orderings of the compressed data stream. Encoding systems also may benefit from having anticipated the need to support both compressed bit orderings. The contract document may specify the LSB to MSB ordering for compressed Type II data blocks. 6.3.6 Note on multiple pages. In Type II files, a document may contain multiple pages (as pages are defined within ODA). These pages may be used to contain the several aperture images of a multiple frame drawing. They may also be used to contain an original image and a scaled down overview image. The sheets of a multiple-sheet paper drawing or multiple-card aperture card drawing may also appear as pages within the same document. An agreement must be reached between parties exchanging data, or in the contract document, that identifies the allowed uses of this mechanism and how these uses are to be distinguished from each other. 6.3.7 Note regarding Type II untiled/tiled. It is understood that permitting untiled Type II data confuses the meaning of Type II. Accordingly, it is necessary that a Type II file be requested as "Type II tiled" or "Type II untiled", whichever is intended. -18- MIL-R-28002A 6.3.8 Note regarding padding of partially filled tiles. In Type II tiled files, a document's size along either dimension will not, in general, be a multiple of 512 pels. This means that some unused data can exist in tiles around any or all of the document's four edges. In the document architecture underlying Appendix A, the unused data outside the clipped pel array is not considered information. Decoding systems should therefore operate as if extraneous data will exist in those pels and guard against its presentation. Compression will, however, be improved if zeros fill the unused pels. Encoding systems might leave garbage in those pels or might zero them out prior to compression. Some systems may get a needed price or performance benefit from not zeroing the data. 6.3.9 Notes regarding orientation. Raster image orientation is dependent on the orientation of the scanned medium relative to the scanning mechanism. For typical technical documentation, the pel path direction is 0 degrees and the line progression direction is 270 degrees. The relationship of pel path to line progression directions for a typical piece of portrait technical documentation is depicted in Figure 1. For typical large format documents, the pel path direction is 90 degrees and the line progression direction is 270 degrees. The relationship of pel path to line progression directions for a typical landscape large format document is depicted in Figure 2. In Figures 1 and 2, four pages are shown. Each has been fed through a scanner in the direction shown by the large arrow. Immediately after scanning and before the quality assurance/visual inspection step, the proper viewing orientation would not be known to the system; each would be identified (some incorrectly) as having a pel path direction of 0 degrees and a line progression direction of 270 degrees. After the visual inspection step, each would have been (correctly) identified with the values shown in Figure 1 placed into their files. Printers and other peripherals may require images to have data presented to them in other than "proper viewing orientation." This is a system-dependent requirement and does not have any impact on the interchange file contents. Note that four other orientations are possible which are the mirror images (around one axis) of the four shown. These could result from scanning an aperture card, paper sepia or transparency from the "wrong" side, either inadvertently or to achieve better image quality. -19- MIL-R-28002A 6.3.10 Note regarding raster image pel density. Typical pel density values might include 100, 200, 240, 300, 400, 600, and 1200 pels per inch. Support for some of these pel densities may be desirable for interchange of data with non-military systems. Appendix A does provide a mechanism for the interchange of any pel density provided it is identified in the document profile as a non-basic value. Since Appendix A has 300 dpi as the default, the defaulting mechanism in Appendix A should not be used for this parameter if it is desired to have 200 dpi. 6.3.11 Note regarding encoding and decoding systems. Systems encoding Type II files have freedom in implementing a narrowly MIL-R-28002A-compliant file writing capability. Systems decoding Type II files, on the other hand, must be able to read files produced by any such encoding system and are therefore necessarily more general in their capabilities. 6.3.12 Note regarding one and zero in bitmap data. Raster data represents each pel in the source document by a zero or a one. The "information" pels in an image are those which make it differ from a blank image. 6.3.13 Notes on scanning quality. Documents are converted to electronic format through the scanning process which renders an image of a document as a set of data elements. FIPS PUB 157, Guideline for Quality Control of Image Scanners, provides guidance on the factors influencing scanned image quality. Typically, scanning quality is enhanced by a control step that enables a workstation operator to improve the quality of the image before final raster graphics file creation. Scanning devices and the processes associated with scanning require regular inspection procedures to ensure high-quality operation of the scanner hardware and appropriate performance of scanner and image quality control personnel. Such inspections are critical in an operating environment where actual raster graphics file usage may occur many years after scanning. Some of the factors involved in raster scanning quality are listed below. Determination of factors a) through n) requires reference to the original document. Factors o) and p) may be determined after the original document is no longer available. a) Contrast. While contrast in a raster image is normally concerned with treatment of grayscale and texture in the image, the treatment of lines, texture and textual characters is also affected by contrast. In binary raster data, intensity-level contrast is not at issue. In this context, contrast is established in the scanning processs itself, and is dependent on the scanning resolution, the sharpness of the image and the threshold level at which a -20- MIL-R-28002A pel is digitized. If contrast is too high, characters may be filled in, pattern-density shading may result in solid regions of set pels, and double lines may be merged. If contrast is too low, fine lines and pattern-density shading may be lost completely. b) Focus. Focus affects the sharpness of a raster image. Diminished focus is characterized by shallow pel-density gradient in one or both dimensions. The result is a "fuzzy" appearance, and reduced susceptibility of the image to optical character recognition or edge-detection algorithm treatment. c) Alignment. Most engineering drawings have many straight line segments aligned with the length and width of the page. If the scanned image is correctly aligned, each line segment in the set is contained in a pel row or column (or contiguous pair, triple, etc. of rows or columns), and the line image appears straight and sharp. If the scanned image is slightly misaligned (or "skewed"), each line segment from the set is stair-stepped in its representation, In addition to affecting the appearance of the image, misalignment reduces the effectiveness of compression routines. d) Aspect ratio. Aspect ratio refers to the scale in the vertical dimension as compared to the horizontal dimension. Unless otherwise specified, the aspect ratio of scanned images is usually unity: i.e., the number of pels required to represent one inch of the drawing horizontally is equal to the number of pels required to represent one inch of the drawing vertically. In measuring the aspect ratio, if linear scales are not present in both dimensions on the drawing itself, the original drawing dimensions must be known, or measurements must be taken from it. Aspect ratio is calculated from the formula: Pv x Lh AR = ------- ; where Ph x Lv AR is the dimensionless aspect ratio. Pv is the number of pels in the vertical dimension. Lh is the represented length in the horizontal dimension. Ph is the number of pels in the horizontal dimension. Lv is the represented length in the vertical dimension. e) Linearity. The number of raster image pels required to represent a unit vertical or horizontal length in the original drawing should ideally be a constant at every point -21- MIL-R-28002A in the image; i.e., the pel-length relationship is linear. If the relationship is non-linear in either the horizontal or vertical direction, diagonal line segments will appear to be curved or wavy, and the image cannot be used for measurement purposes. f) Orthogonality. While most systems are designed so that the two independent scanning dimensions are mutually orthogonal, alignment errors can occur in the scanning process, causing a deviation from orthogonality. This causes rectangles to appear as parallelograms. Orthogonality deviation is the number of degrees by which the angle between the two dimensions differs from 90 degrees. g) Pel density. Pel density of the scanned raster image is normally expressed in image pels per original-drawing inch. Generally speaking, image quality improves with pel density. In the case of images scanned from 35-mm aperture card images, there is a practical limit to the effect of increased pel density on image quality, namely the resolution of the film image. Attempts to represent highly textured drawings with insufficient pel density may result in distortions, such as Moire patterns. h) Coverage. Coverage is the portion of the desired region of the original drawing included in the raster image. A coverage of 100% ensures no data is lost. Determination of coverage by reference to the original drawing is particularly important for those engineering drawings or technical documents that do not have borders. i) Registration. Registration is a measure of the positioning of the raster image in the desired image medium area. Registration is the distance in pel rows or pel columns of the imaged area from the corresponding edges in the raster image. If the image is badly registered, excessive borders may appear and/or some coverage may be lost. j) Resolution. The resolution which an imaging system can reproduce determines the minimum feature size which is recognizable. Due to the linear pickup devices and the non-symmetrical responses of the binarization electronics of many scanners, it is desirable to measure both horizontal, vertical, and diagonal resolution as well as black on white and white on black resolution. k) Scale. The scale (or magnification) of the raster image should accurately and consistently portray the size of the original drawing. The capability of the imaging system to accurately reproduce a scanned image can be measured. Horizontal and vertical scale accuracy can vary independently. It is also useful to determine the black and -22- MIL-R-28002A white scale ratio, which is used to determine whether lines are thickened or thinned by the digitization process. l) Continuity. Continuity is the ability of the imaging system to maintain the complete image without adding breaks to lines. m) Aliasing. Aliasing is a group of image defects generally caused by elements of the scanned image being smaller than and/or not registered with the picture element created by the scanner. An aliasing effect occurs when stair-stepping or jaggedness is introduced in a feature. Aliasing can affect the image quality, readability, and accuracy of the raster image. n) Readability. Readability is a subjective decision made as to whether an image can be read. The sizes of features on the original document affect the readability of the image as do many other factors including the person reading them. Even though it is a subjective evaluation, readability is a useful indication of the quality of the image produced by the system. o) Cleanness. Cleanness is the relative freedom from random "flecks" or amorphous "dirt" spots in the image representation. In addition to detracting from clarity in representing objects, flecks and spots in an image can also severely diminish the degree of compression achievable. If dirt appears in the image area to the extent that the image is obliterated, obscured or defaced, then a major defect exists. The presence of dirt without obliterating, obscuring or defacing the image constitutes a minor defect. Dirtiness can be measured as the dimensionless ratio of the number of "wrong" pel values to the total number of pels in a specified region of the image. p) Evaluation of the scanning process. Evaluation of the scanning process can be achieved quantitatively at the point of acceptance by measuring all factors in a known standard test pattern scanned with each batch of drawings submitted for acceptance. 6.3.14 Note regarding minimizing file size. A tiled Type II data file can have all tiles uncompressed and still be compliant with Appendix A. To avoid unnecessarily long files, the contract document may specify that bitmap tiles only be delivered for those tiles which would negatively compress or unless some needed performance advantage is obtained. For example, some systems may find a need to stop the compression of a tile before it is complete (even though it would have compressed to a smaller size) in order to meet some system timing constraint. The contract document may make a similar requirement for untiled Type II images -23- MIL-R-28002A whereby bitmap images are permitted only for those extremely busy documents (e.g. halftones) which are shown to negatively compress. 6.3.15 Tile index option. In tiled Type II data, the tile index may be specified as an option in the "Application-comments" attribute of the basic page layout object. It contains a list of byte offsets from the beginning of the content information of the content portion to the beginning of each tile in the page. The index is of variable length and cannot be entirely known until the attempt to compress all tiles has been made. This can degrade performance of scanning environments. In editing and other applications, the index aids initial access to the image, but imposes performance and memory penalties on any save operation if the tile index changes due to modifications to individual tiles. There is a potential index integrity problem in that the index may not agree with the actual tile locations. If a system receiving data relies upon this index, it would not be able to process the file. However, the system could read the file by ignoring the index and creating its own index as the file is processed. All of these factors should be thoroughly evaluated before requiring the tile index in the contract deliverables. 6.3.16 Type II data structures. Type II raster binary data consist of Office Document Architecture and Interchange Format (ODA/ODIF) data structures encoded using Abstract Syntax Notation One (ASN.1). The data structures and encoding rules for Type II raster graphics data are presented in Appendix A. 6.3.17 Changes from previous issue. Marginal notations are not used in this revision to identify changes with respect to the previous issue due to the extensiveness of the changes. -24- MIL-R-28002A -25- MIL-R-28002A -26- MIL-R-28002A 6.4 Definitions. 6.4.1 Acronyms. Acronyms used in this specification are defined as follows: a) ANSI. American National Standards Institute b) CCITT. Consultative Committee for International Telegraphy and Telephony c) ISO. International Organization for Standardization d) NIST. National Institute of Standards and Technology e) ODA. Office Document Architecture 6.4.2 Attribute. An element of a constituent of a document that has a name and a value and that expresses a characteristic of this constituent or a relationship with one or more constituents. 6.4.3 Basic page. A page that is not subdivided into subordinate blocks and consisting of only a single type of content, i.e., raster graphics content. 6.4.4 Basic value. Attribute value that is unconditionally allowed in document interchange in the context of a given application profile. 6.4.5 Bitmap. A two- or three-dimensional data field representing a pel array. 6.4.6 Byte boundary. A position in a binary data stream where, if the stream were packed into bytes (octets), an integer number of completely filled bytes would result. 6.4.7 Clipping. The actual pel array to be imaged as determined by applying all clipping parameters. 6.4.8 Compression. An operation performed on raster image data to remove redundant information and thus reduce the stored or interchanged size. Negative compression is the case where this operation results in an increase rather than a decrease in size. 6.4.9 Decoding. The process of deriving a bitmap from an octet string by translating any compression algorithm used to create the octet string. -27- MIL-R-28002A 6.4.10 Decoding system. A program that reads and interprets a file of the specified type, which may not have been produced locally. 6.4.11 Default value. Attribute value that is the standard value in document interchange in the context of a given application profile. 6.4.12 Document application profile (DAP). The result of selecting a particular document architecture level; content architectures; a document profile level; an interchange format level; objects and attributes with classification of attributes into mandatory, non-mandatory, and defaultable; and definitions of basic, non-basic, and default attribute values, and control function parameter values. 6.4.13 Encoding. The process of deriving an octet string from a bitmap by applying a compression algorithm to the bitmap. 6.4.14 Encoding system. A program which produces or outputs for export a file of the specified type. 6.4.15 Header. Control or attribute information that is prefixed to a block of user data. 6.4.16 Initial point. The point relative to which all pels are positioned within a page. It does not necessarily lie at a corner of a tile in the tile grid. 6.4.17 Layout characteristics. A description of the elements, i.e., page, block, of a document and the relationship between the elements. 6.4.18 Line progression. The direction of progression of successive lines of pels in an image. 6.4.19 Non-basic value. Attribute value that is only allowed in document interchange in the context of a given application profile if its use is declared in the document profile. 6.4.20 Null tile. A tile specified in the tiled raster graphics content attributes with no corresponding encoded content. A null tile may be all foreground or all background as identified by its Tile-type attribute. 6.4.21 Octet. A subdivision of bits numbered from 8 to 1 where bit 8 is the most significant bit and bit 1 is the least significant bit. (Also known as a byte.) -28- MIL-R-28002A 6.4.22 Page. A type of layout object or layout object class that corresponds to a rectangular area used as a reference area for presenting the content of the document. 6.4.23 Partial tiles. In a tiled image of a document, the incomplete tiles which may occur on any or all of the four sides of the tile array when the image has been positioned and clipped. Also known as runt tiles. 6.4.24 Pel (Picture element). The smallest graphic element that can be individually addressed within a picture. Synonymous with pixel. 6.4.25 Pel array. A two-dimensional array of pels used to represent a pictorial image. 6.4.26 Pel density. The number of pels per unit distance in a raster image. 6.4.27 Pel path. The direction of progression of successive pels along a line in an image. 6.4.28 Pel spacing. The distance between any two successive pels along a scan line of an image. It is the inverse of such often used terms as pel density, transmission density, or resolution. Note that resolution as discussed in 6.3.13.j is a different concept. 6.4.29 Raster graphics. The electronic data processing medium used to depict any arbitrary assemblage of text characters, graphical figures, or pictorial images with a pel array. 6.4.30 Raster graphics content. The raster graphics portion of a document that is intended for human perception. 6.4.31 Spacing ratio. The ratio of line spacing to pel spacing. 6.4.32 Tile. A rectangular region in a layout object in which all such regions have the same dimensions, no part of any region overlaps any other region, and regions are positioned in a fixed grid, determined by partitioning the layout object into region-sized areas. 6.4.33 Tile Index. An application comment in Type II files which contains a list of byte offsets from the beginning of the first tile to the beginning of each tile in the page. -29- MIL-R-28002A 6.5 Subject term listing. Raster Raster graphics file Image Tiled Untiled Digital Binary MIL-STD-1840 Scanning -30- MIL-R-28002A Appendix A 0 INTRODUCTION This Appendix is a mandatory part of MIL-R-28002. The information contained herein is intended for compliance. It is the definition of an Open Document Architecture (ODA) Document Application Profiles (DAP) named National Institute of Standards and Technology (NIST) ODA Raster DAP. This DAP is suitable for interchanging documents in formatted form. The documents contain only raster images. This DAP has been prepared by the ODA Special Interest Group of the NIST Open Systems Interconnection (OSI) Implementors Workshop. The DAP is defined in accordance with ISO 8613-1 and CCITT T.411 and follows the standardized proforma and notation defined in the proposed Draft Addendum to ISO 8613-1 Annex F (to be published). The DAP is based on ODA as defined in ISO 8613 and the Addendum to ISO 8613, Part 7 (Annex A). Note: There is a parallel effort to incorporate this DAP in the OSI Implementor's Workshop (OIW) Implementation Agreements. Consequently, the format of this Appendix is in accordance with the OIW Styles Manual which follows ISO standards. It is equivalent to Chapter 22 of the September 1990 Working Implementation Agreements except that OIW has proposed that an additional SGML/SDIF based encoding be added. It is anticipated that the DAP will be approved and moved to the Stable Agreements and action initiated to publish a FIPS based on this Appendix and the Stable Agreements. 1 SCOPE AND FIELD OF APPLICATION This DAP specifies an interchange format suitable for transfer of structured documents between equipment designed for raster processing. Such documents contain only bi-tonal raster graphics content, such as engineering drawings and illustrations, although there is no restriction on the minimum size of the image. This document defines a DAP that allows large format raster documents to be interchanged in a formatted form in accordance with ISO 8613. It is assumed that, when negotiation is performed by the service using this DAP, all non-basic features are subject to negotiation. This DAP is independent of the processes carried out in an end system to create, edit, or reproduce raster documents. It is also independent of the means to transfer the document which, for example, may be by means of communication links or exchanged storage media. The features of a document that can be interchanged using this DAP fall into the following categories: o Page format features - these concern how the layout of each page of a document will appear when reproduced; -31- MIL-R-28002A Appendix A o Raster graphics layout and imaging features - these concern how the document content will appear within pages of the reproduced document; and o Raster graphics coding - these concern the raster graphics representations and control functions that make up the document raster graphics content. 2 REFERENCES The following references are required in order to implement this DAP: ISO 8613-1 - Information processing - Text and Office Systems; Open Document Architecture (ODA) and Interchange Format Part 1: Introduction and General Principles (1989) ISO 8613-2 - Information processing - Text and Office Systems; Open Document Architecture (ODA) and Interchange Format Part 2: Document Structures (1989) ISO 8613-4 - Information processing - Text and Office Systems; Open Document Architecture (ODA) and Interchange Format Part 4: Document Profile (1989) ISO 8613-5 - Information processing - Text and Office Systems; Open Document Architecture (ODA) and Interchange Format Part 5: Open Document Interchange Format (1989) ISO 8613-7 - Information processing - Text and Office Systems; Open Document Architecture (ODA) and Interchange Format Part 7: Raster Graphics Content Architectures (1989) ISO 8613-7 - Addendum: Tiled Raster Graphics Addendum to ISO 8613, Part 7 (Annex A) ISO 8613-1 - Draft Addendum: Document Application Profile Proforma and Notation (to be published) ISO 8824 - Information Processing Systems - Open Systems Interconnection - Specification of Abstract Syntax Notation One (ASN.1) ISO 8825 - Information Processing Systems - Open Systems Interconnection - Specification of Basic Encoding Rules for Abstract Syntax Notation One (ASN.1) CCITT T.6 - Facsimile Coding Schemes and Coding Control Functions for Group 4 Facsimile Apparatus, (1988) -32- MIL-R-28002A Appendix A CCITT T.411 Open Document Architecture (ODA) and Interchange Format - Introduction and general principles (1989) CCITT T.412 Open Document Architecture (ODA) and Interchange Format - Document structures (1989) CCITT T.414 Open Document Architecture (ODA) and Interchange Format - Document profile (1989) CCITT T.415 Open Document Architecture (ODA) and Interchange Format - Open document interchange format (1989) CCITT T.417 Open Document Architecture (ODA) and Interchange Format - Raster graphics content architecture (1989) CCITT T.503 Document Application Profile for the Interchange of Group 4 Facsimile Documents 3 DEFINITIONS AND ABBREVIATIONS The definitions given in ISO 8613-1 are applicable to this document. 4 RELATIONSHIP TO OTHER DAPS Functionally, this DAP is similar to the CCITT Recommendation T.503, A Document Application Profile for the Interchange of Group 4 Facsimile Documents. 5 CONFORMANCE In order to conform to this DAP, a data stream representing a document must meet the requirements specified in subclause 5.1. Subclause 5.2 specifies the requirements for implementations that originate and/or receive data streams conforming to this DAP. 5.1 Data stream conformance The following requirements apply to the encoding of data streams that conform to these agreements. o The data stream shall be encoded in accordance with the ASN.1 encoding rules defined in ISO 8825; -33- MIL-R-28002A Appendix A o The data stream shall be structured in accordance with the interchange format defined in clause 8 of this DAP; o The document shall be structured in accordance with only the formatted document architecture class specified in clause 7 of this DAP. In addition, the document shall contain all mandatory constituents specified for that class and may optionally contain constituents permitted for that class as specified in clause 7; o Each constituent shall contain all those attributes specified as required for that constituent in this profile. Other attributes may be specified provided they are permitted for that constituent; o The attributes shall have values within the range of permissible values specified in this profile; o The encoded document shall be structured in accordance with the abstract document architecture defined in ISO 8613-2; o The encoded document shall be structured in accordance with the characteristics defined in clause 6 of this DAP and shall contain only those features defined in clause 6. 5.2 Implementation conformance This subclause states the requirements for implementations claiming conformance to this DAP. An implementation claiming to originate and/or receive data streams conforming to this DAP must complete a conformance test to be defined by a test plan to be developed by DoD and NIST. A conforming receiving implementation must be capable of receiving any data stream conforming to this DAP. "Receiving" means not rejecting a data stream conforming to this DAP and usually, but not always, involves recognizing and further processing the data stream elements. The explicit meaning of "receiving" is determined by a conformance test plan to be developed by DoD and NIST. 6 CHARACTERISTICS SUPPORTED BY THIS DAP This clause describes the characteristics of documents that can be represented by data steams conforming to this profile. This clause also describes how these characteristics are represented in terms of divisional components of the data streams. -34- MIL-R-28002A Appendix A 6.1 Overview This DAP describes the features of ISO 8613 that are needed to support the interchange of documents containing only raster graphics content. It specifies interchange formats for the transfer of structured documents with simple layout structures. This DAP describes documents that can be interchanged in the formatted form, which facilitates the reproduction of a document as intended by the originator. Only one category of content is allowed within the document, namely, a raster graphics content in the formatted processable form, which either facilitates the reproduction of the document content as intended by the originator or the revision of the document content. Subclause 6.4 describes the layout features that can be represented in documents conforming to this DAP. The features are described in terms that are typical of the user-perceived capabilities and semantics found in a raster document interchange environment. For the purpose of interchange, a document is represented as a collection of constituents, each of which is a set of attributes. The constituents that make up a formatted document are defined below in this subclause and are illustrated in the following figure. ----------------------- | Document Profile | | | |-----------------------| | Specific Layout | | Structure | |-----------------------| | Presentation Style | | (optional) | |-----------------------| | Content Portion | | Description | ----------------------- Constituents defined as required must occur in any document that conforms to this profile. Constituents listed as optional may or may not be present in the document, depending on the requirements of the particular document. The required constituents include: o a document profile, -35- MIL-R-28002A Appendix A o layout object descriptions representing a specific layout structure, and o content portion description. The only optional constituent is the presentation style. 6.2 Logical Constituents Not applicable. 6.3 Layout Constituents This subclause describes the features of the layout objects that can be represented in documents conforming to this DAP. 6.3.1 Overview of the Layout Characteristics The document layout structure allows the document content to be laid out and presented in one or more basic pages. Each page consists of only a single raster graphics content representing an engineering drawing, illustration, or other raster scanned image. A specific layout structure of the document conforming to this application profile consists of a two-level hierarchy of a document layout root and a set of basic pages. The basic page contains the content information. The following is a document layout structure derived from this DAP: -------------- | Document | | Layout | | Root | -------------- | -------------- | Basic | | Page(s) | | | -------------- 6.3.2 DocumentLayoutRoot -36- MIL-R-28002A Appendix A A DocumentLayoutRoot is the top level in a document layout structure. Its subordinates consist of a sequence of one or more BasicPage constituent constraints. 6.3.3 BasicPage A BasicPage is a basic layout object that corresponds to the area used for presenting the raster image content of the document. 6.3.3.1 Page Dimensions A wide variety of page dimensions are supported including those needed for large format raster documents. The dimensions of the pages may be specified as any value, in BMU measurement units. Images may be produced on fold-outs or roll paper and may be of either portrait or landscape orientations. Dimensions equivalent to or less than the actual (nominal) page sizes of ANSI E in both portrait and landscape orientations are basic values. Larger dimensions (F-K) including those produced from roll paper are non-basic and their use must be indicated in the document profile. Although ISO A0-A4 sizes are not generally used, the A1-A4 sizes do fall within the range of the ANSI E sizes and therefore could be considered basic values (See table 2). A0 size is a non-basic value. The default dimensions are the Common Assured Reproduction Area (CARA) of North American Letter (A). Any default page dimensions may be specified in the document profile subject to the maximum dimensions defined above by using the Page-dimensions attribute. The Page-position attribute may be used to specify the position of the pel array image on the page. Although actual page dimensions may be used allowing for the raster content to completely fill a page leaving no borders, it is advised that the assured reproduction area (ARA) listed in table 1 be used wherever feasible. See ISO 8613-2, subclause 7.3, General rules for positioning pages on presentation surfaces. 6.3.3.2 Nominal Page Sizes The nominal page sizes that may be specified are listed in Table 1. These may be specified in portrait or landscape orientations. All values of nominal page size up to ANSI E size are basic. All sizes larger than ANSI E size and roll paper are non-basic and their use in a document must be indicated in the document profile using the Medium-type attribute (See table 2). -37- MIL-R-28002A Appendix A Any of the nominal page sizes defined in Table 1, subject to the restriction specified above, may be specified as the default value in the document profile. Table 1 also includes the recommended assured reproduction area (ARA). Information loss may occur when a document is reproduced if the dimensions of the BasicPage exceed the ARA for the specified nominal page size. Table 1 Dimensions for Various Page Sizes Page Type Size Size (BMU) ARA (BMU) - Metric (mm) ISO-A4 210X297 9920 x 14030 9240 x 13200 ISO-A3 297X420 14030 x 19840 13200 x 18480 ISO-A2 420X594 19840 x 28060 18898 x 27118 ISO-A1 594X840 28060 x 39680 26173 x 37843 ISO-A0 840X1188 39680 x 56120 37843 x 54283 - ANSI, North American(NA) (inches) NA-A 8.5X11 10200 x 13200 9240 x 12400 NA-B 11X17 13200 x 20400 12744 x 19656 NA-C 17X22 20400 x 26400 19500 x 25800 NA-D 22X34 26400 x 40800 25800 x 39600 NA-E 34X44 40800 x 52800 39600 x 52200 NA-F 28X40 33600 x 48000 31400 x 47400 NA-G 11X90 13200 x 108000 12400 x 106800 NA-H 28X143 33600 x 171600 31400 x 170400 NA-J 34X176 40800 x 211200 39600 x 210000 NA-K 40X143 48000 x 171600 47400 x 170400 NA-Legal 8.5X14 10200 x 16800 9240 x 15480 - Foldouts Small 11X14 13200 x 16800 12744 x 15480 NA-B 11X17 (same as NA-B above) The above page sizes are for the portrait orientation. -38- MIL-R-28002A Appendix A Table 2 Layout Attributes Default Non-Basic Attributes Basic Values Values Values Page Dimensions* CARA NA A-F, CARA NA-A ARA NA G-K CARA NA-Legal ISO A0 ISO A4-A1 11" roll Small Foldout Medium-type* NA A-F, NA-A NA G-K (Nominal page NA-Legal, ISO A0 size) ISO A4-A1 11" roll Small Foldout * see Table 1 6.4 Document Layout Control A document layout structure contains only a basic page with content information. Each raster graphics content must be allocated to a single basic page. A page containing tiled raster graphics content may consist of as many tiles as is necessary to represent the image in digital form. 6.5 Content Layout and Imaging Control A document may contain only raster graphics content portions as specified in ISO 8613-7. 6.5.1 Raster Graphics Content Architecture Only the formatted processable raster graphics content architecture class is supported by this profile. The content architecture class associated with a basic page is specified using the document architecture class attribute Content- architecture-class. The default value that must be specified in the document profile is formatted processable raster content architectures. When using raster graphics content, only one content portion may be associated with a basic page. -39- MIL-R-28002A Appendix A 6.5.2 Raster Graphics Encoding Methods Three encoding methods, CCITT T.6 (untiled), Tiled, and Bitmap are supported by this profile as basic values. Neither the CCITT T.4 one dimensional method nor the CCITT T.4 two dimensional method is supported. The CCITT Recommendation T.6 Group 4 compression algorithm shall be used in all cases, tiled and untiled, except where it is more efficient to retain an image or tile image in bitmap format or to specify a tile as being either all background or all foreground. When the coding type is specified as CCITT T.6, the encoding must be compressed and the "code extension" technique in T.6 encoding is not used. That is to say that uncompressed data cannot occur within a T.6 encoded data stream. Thus, there is no need for a default value of the Compression attribute and this attribute will not appear in the description of the raster content. In a content portion, it is required that the Number-of-pels-per- line parameter of the Coding-attributes be specified. The use of the Number-of-lines parameter is optional. The value of these parameters shall be a positive number. Otherwise, no constraints are placed on these parameters by this profile. This profile places no constraints on the size of the pel arrays that may be used as long as the size does not exceed the page dimension size. The type of coding method used is specified by the attribute Type-of-coding. The use of this attribute is mandatory in the Document-architecture-defaults of the document profile to define the default value of either T.6 encoding (untiled) or Tiled encoding. The use of this attribute in the description of the content portions is non-mandatory. If this attribute is not specified for a particular content portion, then the default value specified in the Document-architecture-defaults of the document profile is used. If the Tiled encoding method is used, the default value of 512 for the Number-of-pels-per-tile-line and Number-of-lines-per-tile must be used. No other values are supported, therefore these two attributes do not need to be specified. If the Tile-types attribute is not present, then all tiles will be T.6 encoded. If it is present, then there must be a value specified for each tile in which case only null background, null foreground, T.6 encoded, or bitmap encoded values are supported. T.4 one dimensional and T.4 two dimensional encodings are not supported. There are no restrictions on the use of the Tiling-offset other than that specified in ISO 8613-7 Addendum. See table 3 for a tabulated list of the attributes and their basic, default, and non-basic values. -40- MIL-R-28002A Appendix A 6.5.3 Raster Presentation Raster presentation is controlled by the presentation attributes specified in ISO 8613-7. This DAP provides for additional constraints on these presentation attributes as specified below. The basic Pel-path values supported by this profile are 0 and 90 degrees. The Pel-path values of 180 and 270 degrees are non- basic. The basic Line-progression value supported by this profile is 270 degrees. The Line-progression value of 90 degrees is non-basic. The basic Pel-spacing values supported by this profile are the ratios equal to 6 and 4 BMU between adjacent pels. This corresponds to equivalent resolutions of 200 and 300 pels per 25.4mm (1 in.), respectively when the BMU is interpreted as 1/1200 inch. Values for Pel-spacing other than these ratios are non-basic, i.e., 5, 3, 2, and 1 BMU. These correspond to equivalent resolutions of 240, 400, 600, and 1200 pels per 25.4mm (1 in.). There are no restrictions on the use of the Clipping attribute. The Spacing-ratio and Image-dimensions attributes are not supported. See table 4 for a tabulated list of the attributes and their basic, default, and non-basic values. -41- MIL-R-28002A Appendix A Table 3 Content Coding Attributes Default Non-Basic Attributes Basic Values Values Values Number-of-pels- any positive None None per-line integer Number-of-lines any positive None None integer Tiling-offset* (any non-neg (0,0) None integer < 512, any non-neg integer < 512) Tile-types* T.6 encoded T.6 encoded None bitmap encoded null background null foreground Type-of-coding T.6 encoding T.6 encoding None (untiled) bitmap (untiled) tiled * Only used if Type-of-coding is "tiled" Table 4 Presentation Attributes Default Non-Basic Attributes Basic Values Values Values Pel-path 0, 90 deg 0 deg 180, 270 deg Line-progression 270 deg 270 deg 90 deg Pel-spacing 6, 4 BMU 4 BMU (300) 5,3,2,1 BMU (200, 300) Clipping Two Coord. (0,0), None Pairs (any (N-1, L-1) non-negative integer, any non-negative integer) -42- MIL-R-28002A Appendix A 6.6 Miscellaneous Features Within the coding for BasicPage, specification of the attribute Application-comments is optional. However, when used in conjunction with the Type-of-coding of 'Tiled', it contains a sequence of positive integers, one for each tile in the content portion. The sequence of integers is a set of indices representing the octet offsets to the beginning of the respective tiles, starting from the beginning of the "content-information". A tile index of zero (0) will indicate that the respective tile is null and not included in the interchange. The integers will be sequenced in the same order as the tiles. The tiles will be sequenced primarily in the Pel-path and secondarily in the Line- progression direction as defined by the presentation attributes. 6.7 Document Management Features Every document interchanged in accordance with this DAP must include a document profile containing information which relates to the document as a whole. The document profile used in this DAP must identify the contents as raster graphics data. The features specified by the document profile are listed below. A definition of the information contained in these features is given in the corresponding attribute definitions in ISO 8613-4. Presence of document constituents: o specific layout structure; o presentation styles (optional). Document characteristics: o document application profile; o document application profile defaults; o document architecture class; o content architecture class; o interchange format class; o ODA version date; o raster graphics content defaults. -43- MIL-R-28002A Appendix A Non-basic document characteristics: o page dimensions; o medium type; o raster graphics presentation features. The attributes applicable to the document profile are defined in Table 5. The following notation is used in the class column of this table: o m mandatory attribute o nm non-mandatory attribute o d defaultable attribute Capital letters (M, NM, and D) are used for groups of attributes. -44- MIL-R-28002A Appendix A Table 5 Document Profile Attributes Attribute Class Permissible Values Specific-layout-structure m present Presentation-styles nm present Document-characteristics M Document-architecture-class m formatted Document-application-profile m {-- See clause 8 for a definition of the permitted values for this attribute. --} Content-architecture-classes m {2 8 2 7 2} Interchange-format-class m B ODA-version m ISO 8613, 1989-07-04 Document-architecture-defaults M Content-architecture-class m formatted processable Type-of-coding nm T.6 Encoding (default) Tiled Encoding Page-dimensions nm See list in table 1, (Default value is NA-A,9240 x 13200 BMU) Medium-types nm See list in table 1, (Default value is NA-A,9240 x 13200 BMU) Page-position nm any coordinate pair within page Raster-gr-content-defaults NM Pel-path nm 0, 90, 180, 270 degrees (0 is normal default) Line-progression nm 90, 270 degrees (270 is normal default) -45- MIL-R-28002A Appendix A Clipping nm any coordinate pair within page Pel-spacing nm 6 BMU (200 pels/in.) 5 BMU (240 pels/in.) 4 BMU (300 pels/in.) 3 BMU (400 pels/in.) 2 BMU (600 pels/in.) 1 BMU (1200 pels/in.) (Normal default is 4 BMU) Non-basic-doc-characteristics NM Page-dimensions nm See table 1, NA-F through NA-K, roll paper Medium-types nm See table 1, NA-F through NA-K, roll paper Raster-gr-presentation- features NM Pel-path nm 180, 270 degrees Line-progression nm 90 degrees Pel-spacing nm 5 BMU (240 pels/in.) 3 BMU (400 pels/in.) 2 BMU (600 pels/in.) 1 BMU (1200 pels/in.) Document-management-attributes M Document Reference m Any string of characters 7 SPECIFICATION OF CONSTITUENT CONSTRAINTS 7.1 Document Profile Constraints 7.1.1 Macro Definitions -- Basic page dimensions. -- DEFINE(BasicPageDimension," { #horizontal { <=40800 },#vertical{ <=52800}, -46- MIL-R-28002A Appendix A -- Any size equal to or smaller than the actual page size of ISO A1 and ANSI E portrait. -- | #horizontal { <=52800 },#vertical{ <=40800 } } -- Any size equal to or smaller than the actual page size of ISO A1 and ANSI E landscape. -- ") -- Non-basic page dimensions. -- DEFINE(NonBasicPageDimensions," { #horizontal {40801..48000}, #vertical {52801..211200} -- Any size larger than the range of basic values in ANSI E portrait and equal to or smaller than the full size of ANSI K portrait. -- | #horizontal {52801..211200}, #vertical {40801..48000}} -- Any size larger than the range of basic values in ANSI E landscape and equal to or smaller than the full size of ANSI K landscape. -- ") DEFINE(NominalPageSizes," -- ISO Page Sizes -- #horizontal {9920}, #vertical {14030} -- ISO A4 Portrait (210mm x 297mm) -- | #horizontal {14030}, #vertical{9920} -- ISO A4 Landscape (297mm x 210mm) -- | #horizontal {14030}, #vertical{19843} -- ISO A3 Portrait (297mm x 420mm) -- | #horizontal {19843}, #vertical{14030} -- ISO A3 Landscape (420mm x 297mm) -- | #horizontal {19843}, #vertical{28063} -- ISO A2 Portrait (420mm x 594mm) -- | #horizontal {28063}, #vertical{19843} -- ISO A2 Landscape (594mm x 420mm) -- | #horizontal {28063}, #vertical{39732} -- ISO A1 Portrait (594mm x 841mm) -- | #horizontal {39732}, #vertical{28063} -- ISO A1 Landscape (841mm x 594mm) -- | #horizontal {39732}, #vertical{56173} -- ISO A0 Portrait (841mm x 1189mm) -- | #horizontal {56173}, #vertical{39732} -- ISO A0 Landscape (1189mm x 841mm) -- -- ANSI Page Sizes -- | #horizontal {10200}, #vertical{13200} -- ANSI A Portrait (8.5in x 11in) -- | #horizontal {13200}, #vertical{10200} -47- MIL-R-28002A Appendix A -- ANSI A Landscape (11in x 8.5in) -- | #horizontal {10200}, #vertical{16800} -- ANSI Legal Portrait (8.5in x 14in) -- | #horizontal {16800}, #vertical{10200} -- ANSI Legal Landscape (14in x 8.5in) -- | #horizontal {13200}, #vertical{20400} -- ANSI B Portrait (11in x 17in) -- | #horizontal {20400}, #vertical{13200} -- ANSI B Landscape (17in x 11in) -- | #horizontal {20400}, #vertical{26400} -- ANSI C Portrait (17in x 22in) -- | #horizontal {26400}, #vertical{20400} -- ANSI C Landscape (22in x 17in) -- | #horizontal {26400}, #vertical{40800} -- ANSI D Portrait (22in x 34in) -- | #horizontal {40800}, #vertical{26400} -- ANSI D Landscape (34in x 22in) -- | #horizontal {40800}, #vertical{52800} -- ANSI E Portrait (34in x 44in) -- | #horizontal {52800}, #vertical{40800} -- ANSI E Landscape (44in x 34in) -- | #horizontal {33600}, #vertical{48000} -- ANSI F Portrait (28in x 40in) -- | #horizontal {48000}, #vertical{33600} -- ANSI F Landscape (40in x 28in) -- | #horizontal {13200}, #vertical{108000} -- ANSI G Portrait (11in x 90in) -- | #horizontal {108000}, #vertical{13200} -- ANSI G Landscape (90in x 11in) -- | #horizontal {33600}, #vertical{171600} -- ANSI H Portrait (28in x 143in) -- | #horizontal {171600}, #vertical{33600} -- ANSI H Landscape (143in x 28in) -- | #horizontal {40800}, #vertical{211200} -- ANSI J Portrait (34in x 176in) -- | #horizontal {211200}, #vertical{40800} -- ANSI J Landscape (176in x 34in) -- | #horizontal {48000}, #vertical{171600} -- ANSI K Portrait (40in x 143in) -- | #horizontal {171600}, #vertical{48000} -- ANSI K Landscape (143in x 40in) -- -- Foldouts -- | #horizontal {13200}, #vertical{16800} -- Foldout Portrait (11in x 14in) -- | #horizontal {16800}, #vertical{13200} -- Foldout Landscape (14in x 11in) -- | #horizontal {13200}, #vertical{>= 16801} -- Any portrait size larger than the typical foldout size (11in x 14in) including 11 inch roll paper -- -48- MIL-R-28002A Appendix A | #horizontal {>= 16801},#vertical{13200} -- Any landscape size larger than the typical foldout size (14in x 11in) including 11 inch roll paper -- ") DEFINE(FDA," formatted (0)") DEFINE(DAC," Document-profile{#Document-characteristics {#Document-architecture-class}} ") DEFINE(FPR," {2 8 2 7 2}") -- Raster formatted processable -- 7.1.2 Constituent Constraints 7.1.2.1 DocumentProfile { -- Presence of document constituents -- $FDA: REQ Specific-layout-structure {'present'}, PERM Presentation-styles {'present'}; -- Document characteristics -- REQ Document-application-profile {-- See clause 8 for a definition of the permitted values for this attribute. --}, REQ Doc-appl-profile-defaults { -- Document architecture defaults -- REQ #content-architecture-class {$FPR}, PERM #dimensions {$BasicPageDimensions $NonBasicPageDimensions}, PERM #medium-type { REQ #nominal-page-size {$NominalPageSizes}, REQ #side-of-sheet {ANY_VALUE} }, PERM #type-of-coding {'T6 encoding' | 'tiled encoding'}, PERM #page-position {ANY_VALUE}, PERM raster-gr-contents-defaults { PERM #pel-path {ANY_VALUE}, PERM #line-progression {ANY_VALUE}, PERM #pel-spacing {ANY_RATIO = 6/1 4/1}, -49- MIL-R-28002A Appendix A DIS #compression {'uncompressed'}, PERM #clipping {ANY_VALUE}, REQ Document-architecture-class {$FDA}, REQ Content-architecture-classes {$FPR}, REQ Interchange-format-class {-- See clause 8 for a definition of the permitted values for this attribute. --}, REQ ODA-version {#standard-or-recommendation { ::= "ISO 8613"}, #publication-date { ::= "1989-07-04"} }, -- Non-basic document characteristics -- PERM #Page-dimensions {$NonBasicPageDimensions}, PERM #Medium-types { REQ #nominal-page-size {$NominalPageSizes}, REQ #side-of-sheet {ANY_VALUE}, PERM #Ra-gr-presentation-features { PERM #pel-path {'180-degrees' '270-degrees'}, PERM #line-progression {'90-degrees'}, PERM #pel-spacing {ANY_RATIO <> 6/1 4/1}, DIS #compression {'uncompressed'}, -- Document management attributes -- REQ Document-reference {ANY_VALUE}}; 7.2 Logical Constituent Constraints No logical constituents applicable in this subclause. 7.3 Layout Constituent Constraints 7.3.1 Diagrams of Relationships of Layout Constituents The notation used for the structure diagrams is that specified in Annex A of ISO 8613-2. -50- MIL-R-28002A Appendix A -------------- | Document | | Layout | | Root | -------------- | REP -------------- | Basic | | Page | | | -------------- 7.3.2 Macro Definitions None Applicable. 7.3.3 Factor Constraints FACTOR: ANY-LAYOUT { SPECIFIC: PERM Object-type {VIRTUAL}, PERM Object-identifier {ANY_VALUE}, PERM Subordinates {VIRTUAL}, PERM User-visible-name {ANY_VALUE}, PERM User-readable-comment {ANY_VALUE}, } FACTOR: ANY-PAGE :ANY-LAYOUT { SPECIFIC: PERM Object-type {'BASIC-PAGE'}, PERM Dimensions {$BasicPageDimensions | $NonBasicPageDimensions}, PERM Page-position {ANY_VALUE}, } 7.3.4 Constituent Constraints 7.3.4.1 DocumentLayoutRoot DocumentLayoutRoot : ANY-LAYOUT { SPECIFIC: REQ Object-type {'DOCUMENT_LAYOUT_ROOT'}, -51- MIL-R-28002A Appendix A REQ Subordinates {SUB_ID_OF(BasicPage)+}, } 7.3.4.2 BasicPage BasicPage : ANY-PAGE { SPECIFIC: REQ Object-type {'BASIC_PAGE'}, PERM Medium-type {#nominal-page-size {NON_BASIC}, #side-of-sheet {ANY_VALUE}}; PERM Application-comments {SEQ_INTEGERS}, -- See subclause 8.2 -- PERM Content-portions {ANY_VALUE}, PERM Dimensions {#horizontal{ #fixed{ANY_VALUE}}, #vertical{#fixed{ANY_VALUE}} }, PERM Position {#fixed{ANY_VALUE}}, PERM Presentation-style {STYLE_ID_OF(PStyle3}, PERM Presentation-attributes { PERM #raster-attributes { PERM Pel-path {ANY_VALUE}, PERM Line-progression {ANY_VALUE}, PERM Pel-spacing {ANY_VALUE}, PERM Clipping {ANY_VALUE} } }; } 7.4 Layout Style Constraints No layout style constraints applicable in this subclause. 7.5 Presentation Style Constraints 7.5.1 Macro Definitions DEFINE(R-Pres-Attr," PERM Pel-path {ANY_VALUE}, PERM Line-progression {ANY_VALUE}, PERM Pel-spacing {ANY_VALUE}, PERM Clipping {ANY_VALUE}, ") -52- MIL-R-28002A Appendix A 7.5.2 Factor Constraints FACTOR: ANY-PRESENTATION-STYLE { REQ Presentation-style-identifier {ANY_VALUE}, PERM User-readable-comments {ANY_VALUE}, PERM User-visible-name {ANY_VALUE}, } 7.5.3 Constituent Constraints 7.5.3.1 PStyle3 PStyle3 :ANY-PRESENTATION-STYLE { REQ Content-architecture-class {$FPR}, PERM Presentation-attributes {$R-Pres-Attr}, } 7.6 Content Portion Constraints 7.6.1 Raster Graphics Content Portion DEFINE(T6, "ASN.1 {2 8 3 7 0}") DEFINE(Bitmap, "ASN.1 {2 8 3 7 3}") DEFINE(Tiled, "ASN.1 {2 8 3 7 5}") PERM Content-identifier-layout {CONTENT_ID_OF(raster-content- portion)}, PERM Type-of-coding {$T6 | $Bitmap | $Tiled}, PERM Coding-attributes { PERM #Number-of-lines {ANY_VALUE}, REQ #Number-of-pels-per-line {ANY_VALUE}, PERM #Number-of-pels-per-tile-line {512}, PERM #Number-of-lines-per-tile {512}, PERM #Tiling-offset {ANY_VALUE}, PERM #Tile-types {'null background' | 'null foreground' | 'T.6 encoded' | 'bitmap encoded'} }, PERM Content-information {RASTER}, -53- MIL-R-28002A Appendix A 7.7 Additional Usage Constraints No other usage constraints are currently defined. 8 INTERCHANGE FORMAT The Interchange Format Class B can be used by applications requiring a binary encoding based on ASN.1. 8.1 Interchange format class B 8.1.1 Interchange format The value of the document profile attribute "interchange format" for this interchange format is "if-b". This form of ODIF is defined in ISO 8613-5. The encoding is in accordance with the Basic Encoding Rules for Abstract Syntax Notation One (ASN.1), as defined in ISO 8825. 8.1.2 DAP identifier The value for the document profile attribute "Document application profile" for this interchange format is represented by the following object identifier. Editor's Note: The proposed object identifier is {1 3 14 11 0 1 1}. 8.1.3 ASN.1 Generation Constraints The following are additional constraints imposed on the ASN.1 generation beyond those defined in ISO 8824 and ISO 8825. 8.1.4 Encoding of Application Comments ISO 8613-5 define the encoding of the attribute Application Comments as an octet string. This DAP requires that the encoding within that octet string be in accordance with the ASN.1 syntax specified in the following module definition. -54- MIL-R-28002A Appendix A NISTDAPSpecification DEFINITION ::= BEGIN EXPORTS Object-Appl-Comm-Encoding; Object-Appl-Comm-Encoding ::= IMPLICIT SEQUENCE OF INTEGER END 8.2 Encoding of Raster Content Information The encoding of raster content information in the bitmap encoding scheme is that specified in subclause 9.3 of the raster graphics content architecture part of ISO 8613-7, that is, the first pel in the order of bits is allocated to the most significant bit of an octet. The encoding of the code words in the Group 4 facsimile encoding scheme is such that the first or only bit of the first code word shall be placed in the least significant bit of the first octet. Subsequent bits of the first and following code words are placed in the direction of more significant bits in the first and following octets. -55- MIL-R-28002A Appendix A, Annex A This annex includes the text material for the ISO 8613-7 Tiled Raster Graphics Addendum which represents the position of ISO/IEC JTC1/SC 18/WG5 after balloting and disposition of all comments on the Tiled Raster Graphics Draft Addendum (January 1990). The document was distributed as a CCITT Study Group VIII document (CCITT/SGVIII/Q.27). A new ISO 8613-7 will be issued after the Colour Addendum is incorporated which is anticipated to be in March 1991. Requirements for the Addendum on Tiled Raster Graphics This addendum provides the ability in ODA to support the interchange of raster graphics content information, structured according to a homogeneous two dimensional array of nonoverlapping square tiles. Tiling of the raster content provides for: - the efficient coding of sparse diagrams; - a choice of the appropriate coding for each tile; - sub-dividing the processing task into that required for each tile; - the ability to process a sub-set of the tiles that form an image; - support for interchange between applications which manipulate tiles. Add the following definition after clause 3.167 of [Recommendation T.417 | ISO 8613-1] 3.168 tile One element of a two dimensional array of non-overlapping rectangular regions of a pel array. Add the following paragraphs after clause 5.3.2 (Discarded pels) of [Recommendation T.417 | ISO 8613-7]. 5.4 Tiling The pel array may be segmented into a two dimensional array of nonoverlapping rectangular regions called tiles. The content information of each tile is coded independently of the content information of the other tiles of the same pel array. Tiling facilitates convenient access to, and/or processing of portions of the pel array independent of access to, and/or processing of other portions. The capability to encode each tile separately as bitmap, compressed or null maximizes the possible compression of the tiled pel array. NOTE - Tiling provides an alternative method for coding of raster graphics content and therefore does not affect the -56- MIL-R-28002A Appendix A, Annex A positioning of the clipped pel array. The basic concepts, pel image model and positioning of pels in a basic layout object continue to apply. Furthermore the attributes for pel array clipping continue to apply to the pel array. The location of pel array content relative to the tile content is specified by the "tiling offset" attribute. Figure 3 illustrates the location of the pel array in the set of tiles. Figure 3 - Location of the pel array in the set of tiles. Tiled raster graphics content information consists of a sequence of tiles ordered in the direction of the pel path and line progression as illustrated in Figure 4. -57- MIL-R-28002A Appendix A, Annex A Figure 4 - Example of the tile content ordering The content of each tile may be T.4, T.6 or bitmap encoded as specified by the coding attributes. Alternatively, it may be omitted if the pels within the tile are either all foreground or all background. Renumber subsequent clauses to take account of the insertion of the new clause 5.4. In the second paragraph of clause 5 (Principles of positioning pels) of [Recommendation T.417 | ISO 8613-7], replace ...in clause 5.4.1. Clauses 5.4.2 and 5.4.3 then ... by ...in clause 5.5.1. Clauses 5.5.2 and 5.5.3 then ... In the third paragraph of what was clause 5.4.1 (Positioning parameters) of [Recommendation T.417 | ISO 8613-7], replace -58- MIL-R-28002A Appendix A, Annex A ... in clauses 5.4.2 and 5.4.3 respectively. by ... in clauses 5.5.2 and 5.5.3 respectively. Add the following to the end of the permissible value list in clause 7.1.1 (Tyep of coding) of [Recommendation T.417 | ISO 8613- 7]. {2 8 3 7 5 } for 'tiled encoding', Add the following to the end of the list of dashed items in the definition area of clause 7.1.1 (Type of coding) of [Recommendation T.417 | ISO 8613-7]. - 'tiled encoding' according to the tiling scheme defined herein, the bitmap encoding scheme, the two dimensional encoding scheme defined in CCITT Recommendation T.6, or the one or two dimensional encoding scheme defined in CCITT Recommendation T.4. Add the following paragraph after the line beginning "An explanation of these coding schemes in clause 7.1.1 (Type of coding) of [Recommendation T.417 | ISO 8613-7]. The value 'tiled encoding' indicates that the tiles in the content portion are each encoded per the value of the associated "tile types" attribute as defined in 7.2.8. Add the following paragraph to the DEFINITION in clause 7.1.1 (Type of coding) of [Recommendation T.417 | ISO 8613-7]. The relationship between the order of pels, the order of encoded bits and the order of encoded octets is the same for tiled, as for untiled bitmap, T.4 and T.6 encoding. Add the following text at the end of the last sentence of clause 7.2.1 of [Recommendation T.417 | ISO 8613-7]. or 'tiled encoding'. Add the following four clauses after clause 7.2.4 (Number of discarded pels) of [Recommendation T.417 | ISO 8613-7]. 7.2.5 Number of lines per tile CLASSIFICATION: Defaultable APPLICABILITY: Formatted processable content architecture class -59- MIL-R-28002A Appendix A, Annex A PERMISSIBLE VALUE: Positive integer DEFAULT VALUE: 512 DEFINITION: This attribute specifies the tile dimension in units of "line spaces" in the direction of line progression. This attribute is only applicable if the value of the attribute "type of coding" is 'tiled encoding'. 7.2.6 Number of pels per tile line CLASSIFICATION: Defaultable APPLICABILITY: Formatted processable content architecture class PERMISSIBLE VALUE: Positive integer DEFAULT VALUE: 512 DEFINITION: This attribute specifies the tile dimension in units of "pel spaces" in the pel path direction. This attribute is only applicable if the value of the attribute "type of coding" is 'tiled encoding'. 7.2.7 Tiling offset CLASSIFICATION: Defaultable APPLICABILITY: Formatted processable content architecture class STRUCTURE: Coordinate pair: X coordinate, Y coordinate PERMISSIBLE VALUES: Coordinate pair: non-negative integer less than 'number of pels per tile line', non-negative integer less than 'number of lines per tile' DEFAULT VALUE: (0,0) DEFINITION: This attribute specifies the location of the pel array within the -60- MIL-R-28002A Appendix A, Annex A tile space by defining the offset of the first pel of the pel array from the first pel position of the first tile. The offset is specified in pel spaces in the direction of the pel path and line spaces in the direction of the line progression. All tiles cover a portion of the pel array. Portions of the tile space outside the pel array are artifacts of tiling and contain no information. This attribute is only applicable if the value of the attribute "type of coding" is 'tiled encoding'. 7.2.8 Tile types CLASSIFICATION: Defaultable APPLICABILITY: Formatted processable content architecture class PERMISSIBLE VALUES: A sequence of one or more data elements with one of the following values, 'null background', 'null foreground', 'bitmap encoded', 'T6 encoded', 'T4 one dimensional encoded','T4 two dimensional encoded' DEFAULT VALUE: All tiles are T.6 encoded. DEFINITION: This attribute indicates the types of coding of tiles in the content portion as a sequence of values. Each value specifies the type of coding of the corresponding tile (see Figure 4) in the content portion as follows. - 'null background', indicating that all pels in the tile are known to be background and the tile has no encoded content, - 'null foreground', indicating that all pels in the tile are known to be foreground and the tile has no encoded content, - 'T6 encoded', indicating that the pels in the tile are encoded as a T.6 octet string, - 'T4 one dimensional encoded', indicating that the pels in the tile are encoded as a T.4 one dimensional octet string, - 'T4 two dimensional encoded', indicating that the pels in the tile are encoded as a T.4 two dimensional octet string, - 'bitmap encoded', indicating that the pels in the tile are encoded as a bitmap octet string. -61- MIL-R-28002A Appendix A, Annex A The number of values is equal to the number of tiles. This attribute is only applicable if the value of the attribute "type of coding" is 'tiled encoding'. In clause 8.2 of [Recommendation T.417 | ISO 8613-7], replace EXPORTS Raster-Graphics-Attributes, One-Of-Four-Angles, One-Of-Two-Angles, Pel-Transmission-Density, Measure-Pair, Clipping, Pel-Spacing, Spacing-Ratio, Image-Dimensions; by EXPORTS Raster-Graphics-Attributes, One-Of-Four-Angles, One-Of-Two-Angles, Pel-Transmission-Density, Pel-Spacing, Spacing-Ratio, Coordinate-Pair; In clause 8.3 of [Recommendation T.417 | ISO 8613-7], replace EXPORTS Raster-Gr-Coding-Attributes, Compression; by EXPORTS Raster-Gr-Coding-Attributes, Compression, Tile-Type; Add the following below the list of EXPORTS in clause 8.3 (Representation of coding attributes) of [Recommendation T.417 | ISO 8613-7]. IMPORTS Coordinate-Pair FROM Raster-Gr-Presentation-Attributes; Add the following to "Raster-Gr-Coding-Attributes" in clause 8.3 (Representation of coding attributes) of [Recommendation T.417 | ISO 8613-7]. -62- MIL-R-28002A Appendix A, Annex A number-of-pels-per-tile-line [6] IMPLICIT INTEGER OPTIONAL, number-of-lines-per-tile [7] IMPLICIT INTEGER OPTIONAL, tiling-offset [8] IMPLICIT Coordinate-Pair OPTIONAL, tile-types [9] IMPLICIT SEQUENCE OF Tile-Type OPTIONAL Add the following after the "Compression" definition in clause 8.3 (Representation of coding attributes) of [Recommendation T.417 | ISO 8613-7]. Tile-Type ::= INTEGER { null-background (0), null-foreground (1), T6-encoded (2), T4-one-dimensional-encoded (3), T4-two-dimensional-encoded (4), bitmap-encoded (5) } In clause 8.4 of [Recommendation T.417 | ISO 8613-7], replace IMPORTS One-Of-Four-Angles, One-Of-Two-Angles, Pel-Transmission-Density, Measure-Pair, Clipping, Pel-Spacing, Spacing-Ratio, Image-Dimensions, FROM Raster-Gr-Presentation-Attributes, Compression, FROM Raster-Gr-Coding-Attributes; by IMPORTS One-Of-Four-Angles, One-Of-Two-Angles, Pel-Transmission-Density, Pel-Spacing, Spacing-Ratio, Coordinate-Pair, FROM Raster-Gr-Presentation-Attributes, Compression, Tile-Type, FROM Raster-Gr-Coding-Attributes; In clause 8.4 (Representation of non-basic features and non- standard defaults) of ISO 8613-7, replace -63- MIL-R-28002A Appendix A, Annex A compression [0] IMPLICIT Compression } by compression [0] IMPLICIT Compression, number-of-pels-per-tile-line [6] IMPLICIT INTEGER, number-of-lines-per-tile [7] IMPLICIT INTEGER, tiling-offset [8] IMPLICIT Coordinate-Pair, tiling-types [9] IMPLICIT Tile-Type } In clause 8.4 (Representation of non-basic features and nonstandard defaults) of ISO 8613-7, replace compression [8] IMPLICIT Compression OPTIONAL } by compression [8] IMPLICIT Compression OPTIONAL, number-of-pels-per-tile-line [11] IMPLICIT INTEGER OPTIONAL, number-of-lines-per-tile [12] IMPLICIT INTEGER OPTIONAL, tiling-offset [13] IMPLICIT Coordinate-Pair OPTIONAL, tiling-types [14] IMPLICIT Tile-Type OPTIONAL } In clause 9 (Coding schemes) of [Recommendation T.417 | ISO 8613- 7], replace - bitmap encoding scheme. by - bitmap encoding scheme; - tiled encoding scheme. Add the following clause after clause 9.3 (Bitmap encoding scheme) of [Recommendation T.417 | ISO 8613-7]. 9.4 Tiled encoding scheme Tiled content information is coded as a structured octet string composed of a sequence of independently coded tiles. Each tile is encoded as one octet string which may be structured or unstructured. All the pels of a tile may be coded according to one of the following coding schemes: -64- MIL-R-28002A Appendix A, Annex A - Group 4 facsimile encoding scheme; - Group 3 facsimile encoding schemes; - bitmap encoding scheme. Alternatively the pels of a tile may be all be background or all be foreground, and not be coded. Add the following to Table 6 in clause 12 (Definition of raster graphics content architecture classes) of [Recommendation T.417 | ISO 8613-7]. Number of pels per tile line - D3) Number of lines per tile - D3) Tiling offset - D3) Tile types - D3) NOTE 3-This attribute is only applicable if the value of the attribute "type of coding" is 'tiled encoding'. Add the following to clause A.2.2 of the Annexes of [Recommendation T.417 | ISO 8613-7]. ---------------------------------------------------------------- [Type of coding] Tiled encoding ---------------------------------------------------------------- ---------------------------------------------------------------- Number of pels Any positive integer 512 per tile line ---------------------------------------------------------------- Number of lines Any positive integer 512 per tile ---------------------------------------------------------------- Tiling offset Coordinate Pair (Any non-negative integer, (0,0) less than 'number of pels per tile line', Any non-negative integer less than 'number of lines per tile') ---------------------------------------------------------------- Tile types sequence of positive compressed as integers in T.6 ---------------------------------------------------------------- -65- MIL-R-28002A Appendix A, Annex A In clause A.2.2 of the Annexes of [Recommendation T.417 | ISO 8613-7], replace NOTE - The attribute "compression" is only applicable if the value of the attribute "type of coding" is 'T6 encoding' or 'T4 two dimensional encoding'. by NOTE - The attribute "compression" is only applicable if the value of the attribute "type of coding" is 'T6 encoding', 'T4 two dimensional encoding' or 'tiled encoding'. Add the following entry to Table C.1 of Annex C of [Recommendation T.417 | ISO 8613-7]. { 2 8 3 7 5 } Identifies 'tiled encoding' 7.1.1 Add the following clause to Annex D of [Recommendation T.417 | ISO 8613-7]. D.3.5 Tiletypes attribute The "tiletypes" attribute is a character string where each character is a digit from the following set defined in clause 8.3: null background (0) null foreground (1) T.6 encoded (2) T.4 one dimensional (3) T.4 two dimensional (4) bitmap encoded (5) The public text defines this in the following manner: rttypes CDATA #IMPLIED If the concrete syntax length quantity for an attribute value is too restrictive in a given instance, the attribute should be redefined as follows: rttypes ENTITY #IMPLIED The ENTITY would contain the same information but could be arbitrarily long. -66- MIL-R-28002A Custodians: Preparing activity: Army - CR OSD-CL Navy - SH (Project ILSS-0042) Air Force - 24 DLA - DH Review activities: Army - AM Air Force - 01, 02 NSA - NS DCA - DC NASA - NA Others - NBS, DOE, GPO, NCS User activities: OSD - IR Army - AL, AT, AV, EA, ER, GL, ME, MI, SM, TE, TM Navy - AS, EC, OS, SA, YD Air Force - 11, 13, 14, 17, 18, 19, 68, 79, 99 -67-