Libav
lclenc.c
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1 /*
2  * LCL (LossLess Codec Library) Codec
3  * Copyright (c) 2002-2004 Roberto Togni
4  *
5  * This file is part of Libav.
6  *
7  * Libav is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * Libav is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
41 #include <stdio.h>
42 #include <stdlib.h>
43 
44 #include "avcodec.h"
45 #include "lcl.h"
46 #include "libavutil/internal.h"
47 #include "libavutil/mem.h"
48 
49 #include <zlib.h>
50 
51 /*
52  * Decoder context
53  */
54 typedef struct LclEncContext {
55 
57 
58  // Image type
59  int imgtype;
60  // Compression type
62  // Flags
63  int flags;
64  z_stream zstream;
66 
67 /*
68  *
69  * Encode a frame
70  *
71  */
72 static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
73  const AVFrame *pict, int *got_packet)
74 {
75  LclEncContext *c = avctx->priv_data;
76  const AVFrame * const p = pict;
77  int i, ret;
78  int zret; // Zlib return code
79  int max_size = deflateBound(&c->zstream, avctx->width * avctx->height * 3);
80 
81  if (!pkt->data &&
82  (ret = av_new_packet(pkt, max_size)) < 0) {
83  av_log(avctx, AV_LOG_ERROR, "Error allocating packet of size %d.\n", max_size);
84  return ret;
85  }
86 
87  if(avctx->pix_fmt != AV_PIX_FMT_BGR24){
88  av_log(avctx, AV_LOG_ERROR, "Format not supported!\n");
89  return -1;
90  }
91 
92  zret = deflateReset(&c->zstream);
93  if (zret != Z_OK) {
94  av_log(avctx, AV_LOG_ERROR, "Deflate reset error: %d\n", zret);
95  return -1;
96  }
97  c->zstream.next_out = pkt->data;
98  c->zstream.avail_out = pkt->size;
99 
100  for(i = avctx->height - 1; i >= 0; i--) {
101  c->zstream.next_in = p->data[0]+p->linesize[0]*i;
102  c->zstream.avail_in = avctx->width*3;
103  zret = deflate(&c->zstream, Z_NO_FLUSH);
104  if (zret != Z_OK) {
105  av_log(avctx, AV_LOG_ERROR, "Deflate error: %d\n", zret);
106  return -1;
107  }
108  }
109  zret = deflate(&c->zstream, Z_FINISH);
110  if (zret != Z_STREAM_END) {
111  av_log(avctx, AV_LOG_ERROR, "Deflate error: %d\n", zret);
112  return -1;
113  }
114 
115  pkt->size = c->zstream.total_out;
116  pkt->flags |= AV_PKT_FLAG_KEY;
117  *got_packet = 1;
118 
119  return 0;
120 }
121 
122 /*
123  *
124  * Init lcl encoder
125  *
126  */
128 {
129  LclEncContext *c = avctx->priv_data;
130  int zret; // Zlib return code
131 
132  c->avctx= avctx;
133 
134  assert(avctx->width && avctx->height);
135 
136  avctx->extradata= av_mallocz(8);
137 
138  avctx->coded_frame = av_frame_alloc();
139  if (!avctx->coded_frame)
140  return AVERROR(ENOMEM);
141 
143  avctx->coded_frame->key_frame = 1;
144 
145  // Will be user settable someday
146  c->compression = 6;
147  c->flags = 0;
148  c->imgtype = IMGTYPE_RGB24;
149  avctx->bits_per_coded_sample= 24;
150 
151  avctx->extradata[0]= 4;
152  avctx->extradata[1]= 0;
153  avctx->extradata[2]= 0;
154  avctx->extradata[3]= 0;
155  avctx->extradata[4]= c->imgtype;
156  avctx->extradata[5]= c->compression;
157  avctx->extradata[6]= c->flags;
158  avctx->extradata[7]= CODEC_ZLIB;
159  c->avctx->extradata_size= 8;
160 
161  c->zstream.zalloc = Z_NULL;
162  c->zstream.zfree = Z_NULL;
163  c->zstream.opaque = Z_NULL;
164  zret = deflateInit(&c->zstream, c->compression);
165  if (zret != Z_OK) {
166  av_log(avctx, AV_LOG_ERROR, "Deflate init error: %d\n", zret);
167  return 1;
168  }
169 
170  return 0;
171 }
172 
173 /*
174  *
175  * Uninit lcl encoder
176  *
177  */
179 {
180  LclEncContext *c = avctx->priv_data;
181 
182  av_freep(&avctx->extradata);
183  deflateEnd(&c->zstream);
184 
185  av_frame_free(&avctx->coded_frame);
186 
187  return 0;
188 }
189 
191  .name = "zlib",
192  .long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) ZLIB"),
193  .type = AVMEDIA_TYPE_VIDEO,
194  .id = AV_CODEC_ID_ZLIB,
195  .priv_data_size = sizeof(LclEncContext),
196  .init = encode_init,
197  .encode2 = encode_frame,
198  .close = encode_end,
199  .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
200 };