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vp8.h
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1 /*
2  * VP8 compatible video decoder
3  *
4  * Copyright (C) 2010 David Conrad
5  * Copyright (C) 2010 Ronald S. Bultje
6  * Copyright (C) 2010 Fiona Glaser
7  * Copyright (C) 2012 Daniel Kang
8  *
9  * This file is part of FFmpeg.
10  *
11  * FFmpeg is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU Lesser General Public
13  * License as published by the Free Software Foundation; either
14  * version 2.1 of the License, or (at your option) any later version.
15  *
16  * FFmpeg is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19  * Lesser General Public License for more details.
20  *
21  * You should have received a copy of the GNU Lesser General Public
22  * License along with FFmpeg; if not, write to the Free Software
23  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24  */
25 
26 #ifndef AVCODEC_VP8_H
27 #define AVCODEC_VP8_H
28 
29 #include "libavutil/buffer.h"
30 
31 #include "h264pred.h"
32 #include "thread.h"
33 #include "vp56.h"
34 #include "vp8dsp.h"
35 
36 #if HAVE_PTHREADS
37 # include <pthread.h>
38 #elif HAVE_OS2THREADS
39 # include "compat/os2threads.h"
40 #elif HAVE_W32THREADS
41 # include "compat/w32pthreads.h"
42 #endif
43 
44 #define VP8_MAX_QUANT 127
45 
46 enum dct_token {
59 
61 };
62 
63 // used to signal 4x4 intra pred in luma MBs
64 #define MODE_I4x4 4
65 
70 };
71 
73  VP8_SPLITMVMODE_16x8 = 0, ///< 2 16x8 blocks (vertical)
74  VP8_SPLITMVMODE_8x16, ///< 2 8x16 blocks (horizontal)
75  VP8_SPLITMVMODE_8x8, ///< 2x2 blocks of 8x8px each
76  VP8_SPLITMVMODE_4x4, ///< 4x4 blocks of 4x4px each
77  VP8_SPLITMVMODE_NONE, ///< (only used in prediction) no split MVs
78 };
79 
80 typedef struct VP8FilterStrength {
85 
86 typedef struct VP8Macroblock {
88  // TODO: make it possible to check for at least (i4x4 or split_mv)
89  // in one op. are others needed?
98  VP56mv bmv[16];
100 
101 typedef struct VP8ThreadData {
102  DECLARE_ALIGNED(16, int16_t, block)[6][4][16];
103  DECLARE_ALIGNED(16, int16_t, block_dc)[16];
104  /**
105  * This is the index plus one of the last non-zero coeff
106  * for each of the blocks in the current macroblock.
107  * So, 0 -> no coeffs
108  * 1 -> dc-only (special transform)
109  * 2+-> full transform
110  */
112  /**
113  * For coeff decode, we need to know whether the above block had non-zero
114  * coefficients. This means for each macroblock, we need data for 4 luma
115  * blocks, 2 u blocks, 2 v blocks, and the luma dc block, for a total of 9
116  * per macroblock. We keep the last row in top_nnz.
117  */
120 #if HAVE_THREADS
121  pthread_mutex_t lock;
122  pthread_cond_t cond;
123 #endif
124  int thread_mb_pos; // (mb_y << 16) | (mb_x & 0xFFFF)
125  int wait_mb_pos; // What the current thread is waiting on.
126 
127 #define EDGE_EMU_LINESIZE 32
130 } VP8ThreadData;
131 
132 typedef struct VP8Frame {
135 } VP8Frame;
136 
137 typedef struct VP8intmv {
138  int x;
139  int y;
140 } VP8intmv;
141 
142 #define MAX_THREADS 8
143 typedef struct VP8Context {
150 
151  uint16_t mb_width; /* number of horizontal MB */
152  uint16_t mb_height; /* number of vertical MB */
153  int linesize;
155 
162 
163  int8_t sign_bias[4]; ///< one state [0, 1] per ref frame type
164  int ref_count[3];
165 
166  /**
167  * Base parameters for segmentation, i.e. per-macroblock parameters.
168  * These must be kept unchanged even if segmentation is not used for
169  * a frame, since the values persist between interframes.
170  */
171  struct {
175  int8_t base_quant[4];
176  int8_t filter_level[4]; ///< base loop filter level
177  } segmentation;
178 
179  struct {
183  } filter;
184 
186 
189 
190  /**
191  * Macroblocks can have one of 4 different quants in a frame when
192  * segmentation is enabled.
193  * If segmentation is disabled, only the first segment's values are used.
194  */
195  struct {
196  // [0] - DC qmul [1] - AC qmul
197  int16_t luma_qmul[2];
198  int16_t luma_dc_qmul[2]; ///< luma dc-only block quant
199  int16_t chroma_qmul[2];
200  } qmat[4];
201 
202  struct {
203  uint8_t enabled; ///< whether each mb can have a different strength based on mode/ref
204 
205  /**
206  * filter strength adjustment for the following macroblock modes:
207  * [0-3] - i16x16 (always zero)
208  * [4] - i4x4
209  * [5] - zero mv
210  * [6] - inter modes except for zero or split mv
211  * [7] - split mv
212  * i16x16 modes never have any adjustment
213  */
214  int8_t mode[VP8_MVMODE_SPLIT + 1];
215 
216  /**
217  * filter strength adjustment for macroblocks that reference:
218  * [0] - intra / VP56_FRAME_CURRENT
219  * [1] - VP56_FRAME_PREVIOUS
220  * [2] - VP56_FRAME_GOLDEN
221  * [3] - altref / VP56_FRAME_GOLDEN2
222  */
223  int8_t ref[4];
224  } lf_delta;
225 
226  uint8_t (*top_border)[16 + 8 + 8];
228 
229  VP56RangeCoder c; ///< header context, includes mb modes and motion vectors
230 
231  /**
232  * These are all of the updatable probabilities for binary decisions.
233  * They are only implictly reset on keyframes, making it quite likely
234  * for an interframe to desync if a prior frame's header was corrupt
235  * or missing outright!
236  */
237  struct {
245  uint8_t token[4][16][3][NUM_DCT_TOKENS - 1];
246  uint8_t mvc[2][19];
248  } prob[2];
249 
252  int update_last; ///< update VP56_FRAME_PREVIOUS with the current one
253  int update_golden; ///< VP56_FRAME_NONE if not updated, or which frame to copy if so
255 
256  /**
257  * If this flag is not set, all the probability updates
258  * are discarded after this frame is decoded.
259  */
261 
262  /**
263  * All coefficients are contained in separate arith coding contexts.
264  * There can be 1, 2, 4, or 8 of these after the header context.
265  */
273 
274  uint8_t colorspace; ///< 0 is the only value allowed (meaning bt601)
275  uint8_t fullrange; ///< whether we can skip clamping in dsp functions
276 
277  int num_jobs;
278  /**
279  * This describes the macroblock memory layout.
280  * 0 -> Only width+height*2+1 macroblocks allocated (frame/single thread).
281  * 1 -> Macroblocks for entire frame alloced (sliced thread).
282  */
284 
285  void (*decode_mb_row_no_filter)(AVCodecContext *avctx, void *tdata, int jobnr, int threadnr);
286  void (*filter_mb_row)(AVCodecContext *avctx, void *tdata, int jobnr, int threadnr);
287 
288  int vp7;
289 
290  /**
291  * Fade bit present in bitstream (VP7)
292  */
294 
295  /**
296  * Interframe DC prediction (VP7)
297  * [0] VP56_FRAME_PREVIOUS
298  * [1] VP56_FRAME_GOLDEN
299  */
300  uint16_t inter_dc_pred[2][2];
301 
302  /**
303  * Macroblock features (VP7)
304  */
309 } VP8Context;
310 
312 
313 int ff_vp8_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
314  AVPacket *avpkt);
315 
317 
318 #endif /* AVCODEC_VP8_H */