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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 "libavutil/buffer.h"
30 
31 #include "vp56.h"
32 #include "vp8dsp.h"
33 #include "h264pred.h"
34 #include "thread.h"
35 #if HAVE_PTHREADS
36 #include <pthread.h>
37 #elif HAVE_OS2THREADS
38 #include "compat/os2threads.h"
39 #elif HAVE_W32THREADS
40 #include "compat/w32pthreads.h"
41 #endif
42 
43 #define VP8_MAX_QUANT 127
44 
45 enum dct_token {
58 
60 };
61 
62 // used to signal 4x4 intra pred in luma MBs
63 #define MODE_I4x4 4
64 
69 };
70 
72  VP8_SPLITMVMODE_16x8 = 0, ///< 2 16x8 blocks (vertical)
73  VP8_SPLITMVMODE_8x16, ///< 2 8x16 blocks (horizontal)
74  VP8_SPLITMVMODE_8x8, ///< 2x2 blocks of 8x8px each
75  VP8_SPLITMVMODE_4x4, ///< 4x4 blocks of 4x4px each
76  VP8_SPLITMVMODE_NONE, ///< (only used in prediction) no split MVs
77 };
78 
79 typedef struct VP8FilterStrength {
84 
85 typedef struct VP8Macroblock {
87  // todo: make it possible to check for at least (i4x4 or split_mv)
88  // in one op. are others needed?
97  VP56mv bmv[16];
99 
100 typedef struct VP8ThreadData {
101  DECLARE_ALIGNED(16, int16_t, block)[6][4][16];
102  DECLARE_ALIGNED(16, int16_t, block_dc)[16];
103  /**
104  * This is the index plus one of the last non-zero coeff
105  * for each of the blocks in the current macroblock.
106  * So, 0 -> no coeffs
107  * 1 -> dc-only (special transform)
108  * 2+-> full transform
109  */
111  /**
112  * For coeff decode, we need to know whether the above block had non-zero
113  * coefficients. This means for each macroblock, we need data for 4 luma
114  * blocks, 2 u blocks, 2 v blocks, and the luma dc block, for a total of 9
115  * per macroblock. We keep the last row in top_nnz.
116  */
119 #if HAVE_THREADS
120  pthread_mutex_t lock;
121  pthread_cond_t cond;
122 #endif
123  int thread_mb_pos; // (mb_y << 16) | (mb_x & 0xFFFF)
124  int wait_mb_pos; // What the current thread is waiting on.
125 
126 #define EDGE_EMU_LINESIZE 32
129 } VP8ThreadData;
130 
131 typedef struct VP8Frame {
134 } VP8Frame;
135 
136 #define MAX_THREADS 8
137 typedef struct VP8Context {
144 
145  uint16_t mb_width; /* number of horizontal MB */
146  uint16_t mb_height; /* number of vertical MB */
147  int linesize;
149 
156 
157  int8_t sign_bias[4]; ///< one state [0, 1] per ref frame type
158  int ref_count[3];
159 
160  /**
161  * Base parameters for segmentation, i.e. per-macroblock parameters.
162  * These must be kept unchanged even if segmentation is not used for
163  * a frame, since the values persist between interframes.
164  */
165  struct {
169  int8_t base_quant[4];
170  int8_t filter_level[4]; ///< base loop filter level
171  } segmentation;
172 
173  struct {
177  } filter;
178 
180 
183 
184  /**
185  * Macroblocks can have one of 4 different quants in a frame when
186  * segmentation is enabled.
187  * If segmentation is disabled, only the first segment's values are used.
188  */
189  struct {
190  // [0] - DC qmul [1] - AC qmul
191  int16_t luma_qmul[2];
192  int16_t luma_dc_qmul[2]; ///< luma dc-only block quant
193  int16_t chroma_qmul[2];
194  } qmat[4];
195 
196  struct {
197  uint8_t enabled; ///< whether each mb can have a different strength based on mode/ref
198 
199  /**
200  * filter strength adjustment for the following macroblock modes:
201  * [0-3] - i16x16 (always zero)
202  * [4] - i4x4
203  * [5] - zero mv
204  * [6] - inter modes except for zero or split mv
205  * [7] - split mv
206  * i16x16 modes never have any adjustment
207  */
209 
210  /**
211  * filter strength adjustment for macroblocks that reference:
212  * [0] - intra / VP56_FRAME_CURRENT
213  * [1] - VP56_FRAME_PREVIOUS
214  * [2] - VP56_FRAME_GOLDEN
215  * [3] - altref / VP56_FRAME_GOLDEN2
216  */
217  int8_t ref[4];
218  } lf_delta;
219 
220  uint8_t (*top_border)[16+8+8];
222 
223  VP56RangeCoder c; ///< header context, includes mb modes and motion vectors
224 
225  /**
226  * These are all of the updatable probabilities for binary decisions.
227  * They are only implictly reset on keyframes, making it quite likely
228  * for an interframe to desync if a prior frame's header was corrupt
229  * or missing outright!
230  */
231  struct {
240  uint8_t mvc[2][19];
241  } prob[2];
242 
245  int update_last; ///< update VP56_FRAME_PREVIOUS with the current one
246  int update_golden; ///< VP56_FRAME_NONE if not updated, or which frame to copy if so
248 
249  /**
250  * If this flag is not set, all the probability updates
251  * are discarded after this frame is decoded.
252  */
254 
255  /**
256  * All coefficients are contained in separate arith coding contexts.
257  * There can be 1, 2, 4, or 8 of these after the header context.
258  */
266 
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 
277 
278 int ff_vp8_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
279  AVPacket *avpkt);
280 
282 
283 #endif /* AVCODEC_VP8_H */