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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 #define MAX_THREADS 8
138 typedef struct VP8Context {
145 
146  uint16_t mb_width; /* number of horizontal MB */
147  uint16_t mb_height; /* number of vertical MB */
148  int linesize;
150 
157 
158  int8_t sign_bias[4]; ///< one state [0, 1] per ref frame type
159  int ref_count[3];
160 
161  /**
162  * Base parameters for segmentation, i.e. per-macroblock parameters.
163  * These must be kept unchanged even if segmentation is not used for
164  * a frame, since the values persist between interframes.
165  */
166  struct {
170  int8_t base_quant[4];
171  int8_t filter_level[4]; ///< base loop filter level
172  } segmentation;
173 
174  struct {
178  } filter;
179 
181 
184 
185  /**
186  * Macroblocks can have one of 4 different quants in a frame when
187  * segmentation is enabled.
188  * If segmentation is disabled, only the first segment's values are used.
189  */
190  struct {
191  // [0] - DC qmul [1] - AC qmul
192  int16_t luma_qmul[2];
193  int16_t luma_dc_qmul[2]; ///< luma dc-only block quant
194  int16_t chroma_qmul[2];
195  } qmat[4];
196 
197  struct {
198  uint8_t enabled; ///< whether each mb can have a different strength based on mode/ref
199 
200  /**
201  * filter strength adjustment for the following macroblock modes:
202  * [0-3] - i16x16 (always zero)
203  * [4] - i4x4
204  * [5] - zero mv
205  * [6] - inter modes except for zero or split mv
206  * [7] - split mv
207  * i16x16 modes never have any adjustment
208  */
209  int8_t mode[VP8_MVMODE_SPLIT + 1];
210 
211  /**
212  * filter strength adjustment for macroblocks that reference:
213  * [0] - intra / VP56_FRAME_CURRENT
214  * [1] - VP56_FRAME_PREVIOUS
215  * [2] - VP56_FRAME_GOLDEN
216  * [3] - altref / VP56_FRAME_GOLDEN2
217  */
218  int8_t ref[4];
219  } lf_delta;
220 
221  uint8_t (*top_border)[16 + 8 + 8];
223 
224  VP56RangeCoder c; ///< header context, includes mb modes and motion vectors
225 
226  /**
227  * These are all of the updatable probabilities for binary decisions.
228  * They are only implictly reset on keyframes, making it quite likely
229  * for an interframe to desync if a prior frame's header was corrupt
230  * or missing outright!
231  */
232  struct {
240  uint8_t token[4][16][3][NUM_DCT_TOKENS - 1];
241  uint8_t mvc[2][19];
243  } prob[2];
244 
247  int update_last; ///< update VP56_FRAME_PREVIOUS with the current one
248  int update_golden; ///< VP56_FRAME_NONE if not updated, or which frame to copy if so
250 
251  /**
252  * If this flag is not set, all the probability updates
253  * are discarded after this frame is decoded.
254  */
256 
257  /**
258  * All coefficients are contained in separate arith coding contexts.
259  * There can be 1, 2, 4, or 8 of these after the header context.
260  */
268 
269  int num_jobs;
270  /**
271  * This describes the macroblock memory layout.
272  * 0 -> Only width+height*2+1 macroblocks allocated (frame/single thread).
273  * 1 -> Macroblocks for entire frame alloced (sliced thread).
274  */
276 
277  void (*decode_mb_row_no_filter)(AVCodecContext *avctx, void *tdata, int jobnr, int threadnr);
278  void (*filter_mb_row)(AVCodecContext *avctx, void *tdata, int jobnr, int threadnr);
279 
280  int vp7;
281 
282  /**
283  * Fade bit present in bitstream (VP7)
284  */
286 
287  /**
288  * Interframe DC prediction (VP7)
289  * [0] VP56_FRAME_PREVIOUS
290  * [1] VP56_FRAME_GOLDEN
291  */
292  uint16_t inter_dc_pred[2][2];
293 
294  /**
295  * Macroblock features (VP7)
296  */
301 } VP8Context;
302 
304 
305 int ff_vp8_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
306  AVPacket *avpkt);
307 
309 
310 #endif /* AVCODEC_VP8_H */