2 * Chinese AVS video (AVS1-P2, JiZhun profile) decoder.
3 * Copyright (c) 2006 Stefan Gehrer <stefan.gehrer@gmx.de>
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26 #include "mpegvideo.h"
28 #define SLICE_MIN_START_CODE 0x00000101
29 #define SLICE_MAX_START_CODE 0x000001af
30 #define EXT_START_CODE 0x000001b5
31 #define USER_START_CODE 0x000001b2
32 #define CAVS_START_CODE 0x000001b0
33 #define PIC_I_START_CODE 0x000001b3
34 #define PIC_PB_START_CODE 0x000001b6
44 #define ESCAPE_CODE 59
55 #define MV_BWD_OFFS 12
128 MV_BWD_D3 = MV_BWD_OFFS,
135 MV_BWD_A3 = MV_BWD_OFFS+8,
140 DECLARE_ALIGNED_8(typedef, struct) {
147 typedef struct residual_vlc_t {
149 int8_t level_add[27];
157 Picture picture; ///< currently decoded frame
158 Picture DPB[2]; ///< reference frames
159 int dist[2]; ///< temporal distances from current frame to ref frames
162 int mb_width, mb_height;
166 int skip_mode_flag; ///< select between skip_count or one skip_flag per MB
167 int loop_filter_disable;
168 int alpha_offset, beta_offset;
170 int mbx, mby; ///< macroblock coordinates
171 int flags; ///< availability flags of neighbouring macroblocks
172 int stc; ///< last start code
173 uint8_t *cy, *cu, *cv; ///< current MB sample pointers
177 /** mv motion vector cache
182 X are the vectors in the current macroblock (5,6,9,10)
183 A is the macroblock to the left (4,8)
184 B is the macroblock to the top (1,2)
185 C is the macroblock to the top-right (3)
186 D is the macroblock to the top-left (0)
188 the same is repeated for backward motion vectors */
193 /** luma pred mode cache
197 int pred_mode_Y[3*3];
199 int l_stride, c_stride;
206 /** intra prediction is done with un-deblocked samples
207 they are saved here before deblocking the MB */
208 uint8_t *top_border_y, *top_border_u, *top_border_v;
209 uint8_t left_border_y[26], left_border_u[10], left_border_v[10];
210 uint8_t intern_border_y[26];
211 uint8_t topleft_border_y, topleft_border_u, topleft_border_v;
213 void (*intra_pred_l[8])(uint8_t *d,uint8_t *top,uint8_t *left,int stride);
214 void (*intra_pred_c[7])(uint8_t *d,uint8_t *top,uint8_t *left,int stride);
215 uint8_t *col_type_base;
218 /* scaling factors for MV prediction */
219 int sym_factor; ///< for scaling in symmetrical B block
220 int direct_den[2]; ///< for scaling in direct B block
221 int scale_den[2]; ///< for scaling neighbouring MVs
227 extern const vector_t ff_cavs_un_mv;
229 static inline void load_intra_pred_luma(AVSContext *h, uint8_t *top,
230 uint8_t **left, int block) {
235 *left = h->left_border_y;
236 h->left_border_y[0] = h->left_border_y[1];
237 memset(&h->left_border_y[17],h->left_border_y[16],9);
238 memcpy(&top[1],&h->top_border_y[h->mbx*16],16);
241 if((h->flags & A_AVAIL) && (h->flags & B_AVAIL))
242 h->left_border_y[0] = top[0] = h->topleft_border_y;
245 *left = h->intern_border_y;
247 h->intern_border_y[i+1] = *(h->cy + 7 + i*h->l_stride);
248 memset(&h->intern_border_y[9],h->intern_border_y[8],9);
249 h->intern_border_y[0] = h->intern_border_y[1];
250 memcpy(&top[1],&h->top_border_y[h->mbx*16+8],8);
251 if(h->flags & C_AVAIL)
252 memcpy(&top[9],&h->top_border_y[(h->mbx + 1)*16],8);
254 memset(&top[9],top[8],9);
257 if(h->flags & B_AVAIL)
258 h->intern_border_y[0] = top[0] = h->top_border_y[h->mbx*16+7];
261 *left = &h->left_border_y[8];
262 memcpy(&top[1],h->cy + 7*h->l_stride,16);
265 if(h->flags & A_AVAIL)
266 top[0] = h->left_border_y[8];
269 *left = &h->intern_border_y[8];
271 h->intern_border_y[i+9] = *(h->cy + 7 + (i+8)*h->l_stride);
272 memset(&h->intern_border_y[17],h->intern_border_y[16],9);
273 memcpy(&top[0],h->cy + 7 + 7*h->l_stride,9);
274 memset(&top[9],top[8],9);
279 static inline void modify_pred(const int_fast8_t *mod_table, int *mode) {
280 *mode = mod_table[*mode];
282 av_log(NULL, AV_LOG_ERROR, "Illegal intra prediction mode\n");
287 static inline void set_mvs(vector_t *mv, enum block_t size) {
290 mv[MV_STRIDE ] = mv[0];
291 mv[MV_STRIDE+1] = mv[0];
296 mv[MV_STRIDE] = mv[0];
302 * initialise predictors for motion vectors and intra prediction
304 static inline void init_mb(AVSContext *h) {
307 /* copy predictors from top line (MB B and C) into cache */
309 h->mv[MV_FWD_B2+i] = h->top_mv[0][h->mbx*2+i];
310 h->mv[MV_BWD_B2+i] = h->top_mv[1][h->mbx*2+i];
312 h->pred_mode_Y[1] = h->top_pred_Y[h->mbx*2+0];
313 h->pred_mode_Y[2] = h->top_pred_Y[h->mbx*2+1];
314 /* clear top predictors if MB B is not available */
315 if(!(h->flags & B_AVAIL)) {
316 h->mv[MV_FWD_B2] = ff_cavs_un_mv;
317 h->mv[MV_FWD_B3] = ff_cavs_un_mv;
318 h->mv[MV_BWD_B2] = ff_cavs_un_mv;
319 h->mv[MV_BWD_B3] = ff_cavs_un_mv;
320 h->pred_mode_Y[1] = h->pred_mode_Y[2] = NOT_AVAIL;
321 h->flags &= ~(C_AVAIL|D_AVAIL);
325 if(h->mbx == h->mb_width-1) //MB C not available
326 h->flags &= ~C_AVAIL;
327 /* clear top-right predictors if MB C is not available */
328 if(!(h->flags & C_AVAIL)) {
329 h->mv[MV_FWD_C2] = ff_cavs_un_mv;
330 h->mv[MV_BWD_C2] = ff_cavs_un_mv;
332 /* clear top-left predictors if MB D is not available */
333 if(!(h->flags & D_AVAIL)) {
334 h->mv[MV_FWD_D3] = ff_cavs_un_mv;
335 h->mv[MV_BWD_D3] = ff_cavs_un_mv;
337 /* set pointer for co-located macroblock type */
338 h->col_type = &h->col_type_base[h->mby*h->mb_width + h->mbx];
341 static inline void check_for_slice(AVSContext *h);
344 * save predictors for later macroblocks and increase
346 * @returns 0 if end of frame is reached, 1 otherwise
348 static inline int next_mb(AVSContext *h) {
355 /* copy mvs as predictors to the left */
357 h->mv[i] = h->mv[i+2];
358 /* copy bottom mvs from cache to top line */
359 h->top_mv[0][h->mbx*2+0] = h->mv[MV_FWD_X2];
360 h->top_mv[0][h->mbx*2+1] = h->mv[MV_FWD_X3];
361 h->top_mv[1][h->mbx*2+0] = h->mv[MV_BWD_X2];
362 h->top_mv[1][h->mbx*2+1] = h->mv[MV_BWD_X3];
363 /* next MB address */
365 if(h->mbx == h->mb_width) { //new mb line
366 h->flags = B_AVAIL|C_AVAIL;
367 /* clear left pred_modes */
368 h->pred_mode_Y[3] = h->pred_mode_Y[6] = NOT_AVAIL;
369 /* clear left mv predictors */
371 h->mv[i] = ff_cavs_un_mv;
374 /* re-calculate sample pointers */
375 h->cy = h->picture.data[0] + h->mby*16*h->l_stride;
376 h->cu = h->picture.data[1] + h->mby*8*h->c_stride;
377 h->cv = h->picture.data[2] + h->mby*8*h->c_stride;
378 if(h->mby == h->mb_height) { //frame end
381 //check_for_slice(h);