3 * VP5 and VP6 compatible video decoder (common features)
5 * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
7 * This file is part of FFmpeg.
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 #ifndef AVCODEC_VP56_H
25 #define AVCODEC_VP56_H
30 #include "bytestream.h"
34 typedef struct vp56_context VP56Context;
39 } DECLARE_ALIGNED(4, , VP56mv);
41 typedef void (*VP56ParseVectorAdjustment)(VP56Context *s,
43 typedef void (*VP56Filter)(VP56Context *s, uint8_t *dst, uint8_t *src,
44 int offset1, int offset2, int stride,
45 VP56mv mv, int mask, int select, int luma);
46 typedef void (*VP56ParseCoeff)(VP56Context *s);
47 typedef void (*VP56DefaultModelsInit)(VP56Context *s);
48 typedef void (*VP56ParseVectorModels)(VP56Context *s);
49 typedef void (*VP56ParseCoeffModels)(VP56Context *s);
50 typedef int (*VP56ParseHeader)(VP56Context *s, const uint8_t *buf,
51 int buf_size, int *golden_frame);
55 int bits; /* stored negated (i.e. negative "bits" is a positive number of
56 bits left) in order to eliminate a negate in cache refilling */
57 const uint8_t *buffer;
59 unsigned int code_word;
74 uint8_t coeff_reorder[64]; /* used in vp6 only */
75 uint8_t coeff_index_to_pos[64]; /* used in vp6 only */
76 uint8_t vector_sig[2]; /* delta sign */
77 uint8_t vector_dct[2]; /* delta coding types */
78 uint8_t vector_pdi[2][2]; /* predefined delta init */
79 uint8_t vector_pdv[2][7]; /* predefined delta values */
80 uint8_t vector_fdv[2][8]; /* 8 bit delta value definition */
81 uint8_t coeff_dccv[2][11]; /* DC coeff value */
82 uint8_t coeff_ract[2][3][6][11]; /* Run/AC coding type and AC coeff value */
83 uint8_t coeff_acct[2][3][3][6][5];/* vp5 only AC coding type for coding group < 3 */
84 uint8_t coeff_dcct[2][36][5]; /* DC coeff coding type */
85 uint8_t coeff_runv[2][14]; /* run value (vp6 only) */
86 uint8_t mb_type[3][10][10]; /* model for decoding MB type */
87 uint8_t mb_types_stats[3][10][2];/* contextual, next MB type stats */
91 AVCodecContext *avctx;
93 VP56DSPContext vp56dsp;
97 uint8_t *edge_emu_buffer_alloc;
98 uint8_t *edge_emu_buffer;
107 int mb_width; /* number of horizontal MB */
108 int mb_height; /* number of vertical MB */
114 int8_t *qscale_table;
116 /* DC predictors management */
117 VP56RefDc *above_blocks;
118 VP56RefDc left_block[4];
119 int above_block_idx[6];
120 DCTELEM prev_dc[3][3]; /* [plan][ref_frame] */
122 /* blocks / macroblock */
124 VP56Macroblock *macroblocks;
125 DECLARE_ALIGNED(16, DCTELEM, block_coeff)[6][64];
128 VP56mv mv[6]; /* vectors for each block in MB */
129 VP56mv vector_candidate[2];
130 int vector_candidate_pos;
132 /* filtering hints */
133 int filter_header; /* used in vp6 only */
134 int deblock_filtering;
135 int filter_selection;
137 int max_vector_length;
138 int sample_variance_threshold;
140 uint8_t coeff_ctx[4][64]; /* used in vp5 only */
141 uint8_t coeff_ctx_last[4]; /* used in vp5 only */
145 /* upside-down flipping hints */
146 int flip; /* are we flipping ? */
147 int frbi; /* first row block index in MB */
148 int srbi; /* second row block index in MB */
149 int stride[4]; /* stride for each plan */
151 const uint8_t *vp56_coord_div;
152 VP56ParseVectorAdjustment parse_vector_adjustment;
154 VP56ParseCoeff parse_coeff;
155 VP56DefaultModelsInit default_models_init;
156 VP56ParseVectorModels parse_vector_models;
157 VP56ParseCoeffModels parse_coeff_models;
158 VP56ParseHeader parse_header;
163 /* huffman decoding */
168 VLC ract_vlc[2][3][6];
169 unsigned int nb_null[2][2]; /* number of consecutive NULL DC/AC */
173 void ff_vp56_init(AVCodecContext *avctx, int flip, int has_alpha);
174 int ff_vp56_free(AVCodecContext *avctx);
175 void ff_vp56_init_dequant(VP56Context *s, int quantizer);
176 int ff_vp56_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
181 * vp56 specific range coder implementation
184 extern const uint8_t ff_vp56_norm_shift[256];
185 void ff_vp56_init_range_decoder(VP56RangeCoder *c, const uint8_t *buf, int buf_size);
187 static av_always_inline unsigned int vp56_rac_renorm(VP56RangeCoder *c)
189 int shift = ff_vp56_norm_shift[c->high];
191 unsigned int code_word = c->code_word;
196 if(bits >= 0 && c->buffer < c->end) {
197 code_word |= bytestream_get_be16(&c->buffer) << bits;
205 #include "x86/vp56_arith.h"
208 #ifndef vp56_rac_get_prob
209 #define vp56_rac_get_prob vp56_rac_get_prob
210 static av_always_inline int vp56_rac_get_prob(VP56RangeCoder *c, uint8_t prob)
212 unsigned int code_word = vp56_rac_renorm(c);
213 unsigned int low = 1 + (((c->high - 1) * prob) >> 8);
214 unsigned int low_shift = low << 16;
215 int bit = code_word >= low_shift;
217 c->high = bit ? c->high - low : low;
218 c->code_word = bit ? code_word - low_shift : code_word;
224 // branchy variant, to be used where there's a branch based on the bit decoded
225 static av_always_inline int vp56_rac_get_prob_branchy(VP56RangeCoder *c, int prob)
227 unsigned long code_word = vp56_rac_renorm(c);
228 unsigned low = 1 + (((c->high - 1) * prob) >> 8);
229 unsigned low_shift = low << 16;
231 if (code_word >= low_shift) {
233 c->code_word = code_word - low_shift;
238 c->code_word = code_word;
242 static av_always_inline int vp56_rac_get(VP56RangeCoder *c)
244 unsigned int code_word = vp56_rac_renorm(c);
246 int low = (c->high + 1) >> 1;
247 unsigned int low_shift = low << 16;
248 int bit = code_word >= low_shift;
251 code_word -= low_shift;
256 c->code_word = code_word;
260 // rounding is different than vp56_rac_get, is vp56_rac_get wrong?
261 static av_always_inline int vp8_rac_get(VP56RangeCoder *c)
263 return vp56_rac_get_prob(c, 128);
266 static av_unused int vp56_rac_gets(VP56RangeCoder *c, int bits)
271 value = (value << 1) | vp56_rac_get(c);
277 static av_unused int vp8_rac_get_uint(VP56RangeCoder *c, int bits)
282 value = (value << 1) | vp8_rac_get(c);
288 // fixme: add 1 bit to all the calls to this?
289 static av_unused int vp8_rac_get_sint(VP56RangeCoder *c, int bits)
296 v = vp8_rac_get_uint(c, bits);
305 static av_unused int vp56_rac_gets_nn(VP56RangeCoder *c, int bits)
307 int v = vp56_rac_gets(c, 7) << 1;
311 static av_unused int vp8_rac_get_nn(VP56RangeCoder *c)
313 int v = vp8_rac_get_uint(c, 7) << 1;
317 static av_always_inline
318 int vp56_rac_get_tree(VP56RangeCoder *c,
319 const VP56Tree *tree,
320 const uint8_t *probs)
322 while (tree->val > 0) {
323 if (vp56_rac_get_prob(c, probs[tree->prob_idx]))
332 * This is identical to vp8_rac_get_tree except for the possibility of starting
333 * on a node other than the root node, needed for coeff decode where this is
334 * used to save a bit after a 0 token (by disallowing EOB to immediately follow.)
336 static av_always_inline
337 int vp8_rac_get_tree_with_offset(VP56RangeCoder *c, const int8_t (*tree)[2],
338 const uint8_t *probs, int i)
341 i = tree[i][vp56_rac_get_prob(c, probs[i])];
347 // how probabilities are associated with decisions is different I think
348 // well, the new scheme fits in the old but this way has one fewer branches per decision
349 static av_always_inline
350 int vp8_rac_get_tree(VP56RangeCoder *c, const int8_t (*tree)[2],
351 const uint8_t *probs)
353 return vp8_rac_get_tree_with_offset(c, tree, probs, 0);
357 static av_always_inline int vp8_rac_get_coeff(VP56RangeCoder *c, const uint8_t *prob)
362 v = (v<<1) + vp56_rac_get_prob(c, *prob++);
368 #endif /* AVCODEC_VP56_H */