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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 Jason Garrett-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 "vp56.h"
30 #include "vp56data.h"
31 #include "vp8dsp.h"
32 #include "h264pred.h"
33 #if HAVE_PTHREADS
34 #include <pthread.h>
35 #elif HAVE_W32THREADS
36 #include "w32pthreads.h"
37 #elif HAVE_OS2THREADS
38 #include "os2threads.h"
39 #endif
40 
41 #define VP8_MAX_QUANT 127
42 
43 enum dct_token {
56 
58 };
59 
60 // used to signal 4x4 intra pred in luma MBs
61 #define MODE_I4x4 4
62 
67 };
68 
70  VP8_SPLITMVMODE_16x8 = 0, ///< 2 16x8 blocks (vertical)
71  VP8_SPLITMVMODE_8x16, ///< 2 8x16 blocks (horizontal)
72  VP8_SPLITMVMODE_8x8, ///< 2x2 blocks of 8x8px each
73  VP8_SPLITMVMODE_4x4, ///< 4x4 blocks of 4x4px each
74  VP8_SPLITMVMODE_NONE, ///< (only used in prediction) no split MVs
75 };
76 
77 typedef struct VP8FilterStrength {
82 
83 typedef struct VP8Macroblock {
85  // todo: make it possible to check for at least (i4x4 or split_mv)
86  // in one op. are others needed?
95  VP56mv bmv[16];
97 
98 typedef struct VP8ThreadData {
99  DECLARE_ALIGNED(16, int16_t, block)[6][4][16];
100  DECLARE_ALIGNED(16, int16_t, block_dc)[16];
101  /**
102  * This is the index plus one of the last non-zero coeff
103  * for each of the blocks in the current macroblock.
104  * So, 0 -> no coeffs
105  * 1 -> dc-only (special transform)
106  * 2+-> full transform
107  */
109  /**
110  * For coeff decode, we need to know whether the above block had non-zero
111  * coefficients. This means for each macroblock, we need data for 4 luma
112  * blocks, 2 u blocks, 2 v blocks, and the luma dc block, for a total of 9
113  * per macroblock. We keep the last row in top_nnz.
114  */
117 #if HAVE_THREADS
118  pthread_mutex_t lock;
119  pthread_cond_t cond;
120 #endif
121  int thread_mb_pos; // (mb_y << 16) | (mb_x & 0xFFFF)
122  int wait_mb_pos; // What the current thread is waiting on.
125 } VP8ThreadData;
126 
127 #define MAX_THREADS 8
128 typedef struct VP8Context {
135 
136  uint16_t mb_width; /* number of horizontal MB */
137  uint16_t mb_height; /* number of vertical MB */
138  int linesize;
140 
147 
148  int8_t sign_bias[4]; ///< one state [0, 1] per ref frame type
149  int ref_count[3];
150 
151  /**
152  * Base parameters for segmentation, i.e. per-macroblock parameters.
153  * These must be kept unchanged even if segmentation is not used for
154  * a frame, since the values persist between interframes.
155  */
156  struct {
160  int8_t base_quant[4];
161  int8_t filter_level[4]; ///< base loop filter level
162  } segmentation;
163 
164  struct {
168  } filter;
169 
171 
174 
175  /**
176  * Macroblocks can have one of 4 different quants in a frame when
177  * segmentation is enabled.
178  * If segmentation is disabled, only the first segment's values are used.
179  */
180  struct {
181  // [0] - DC qmul [1] - AC qmul
182  int16_t luma_qmul[2];
183  int16_t luma_dc_qmul[2]; ///< luma dc-only block quant
184  int16_t chroma_qmul[2];
185  } qmat[4];
186 
187  struct {
188  uint8_t enabled; ///< whether each mb can have a different strength based on mode/ref
189 
190  /**
191  * filter strength adjustment for the following macroblock modes:
192  * [0-3] - i16x16 (always zero)
193  * [4] - i4x4
194  * [5] - zero mv
195  * [6] - inter modes except for zero or split mv
196  * [7] - split mv
197  * i16x16 modes never have any adjustment
198  */
200 
201  /**
202  * filter strength adjustment for macroblocks that reference:
203  * [0] - intra / VP56_FRAME_CURRENT
204  * [1] - VP56_FRAME_PREVIOUS
205  * [2] - VP56_FRAME_GOLDEN
206  * [3] - altref / VP56_FRAME_GOLDEN2
207  */
208  int8_t ref[4];
209  } lf_delta;
210 
211  uint8_t (*top_border)[16+8+8];
213 
214  VP56RangeCoder c; ///< header context, includes mb modes and motion vectors
215 
216  /**
217  * These are all of the updatable probabilities for binary decisions.
218  * They are only implictly reset on keyframes, making it quite likely
219  * for an interframe to desync if a prior frame's header was corrupt
220  * or missing outright!
221  */
222  struct {
231  uint8_t mvc[2][19];
232  } prob[2];
233 
236  int update_last; ///< update VP56_FRAME_PREVIOUS with the current one
237  int update_golden; ///< VP56_FRAME_NONE if not updated, or which frame to copy if so
239 
240  /**
241  * If this flag is not set, all the probability updates
242  * are discarded after this frame is decoded.
243  */
245 
246  /**
247  * All coefficients are contained in separate arith coding contexts.
248  * There can be 1, 2, 4, or 8 of these after the header context.
249  */
257 
258  /**
259  * A list of segmentation_map buffers that are to be free()'ed in
260  * the next decoding iteration. We can't free() them right away
261  * because the map may still be used by subsequent decoding threads.
262  * Unused if frame threading is off.
263  */
267  int num_jobs;
268  /**
269  * This describes the macroblock memory layout.
270  * 0 -> Only width+height*2+1 macroblocks allocated (frame/single thread).
271  * 1 -> Macroblocks for entire frame alloced (sliced thread).
272  */
274 } VP8Context;
275 
276 #endif /* AVCODEC_VP8_H */