rv34: export qp table
[ffmpeg.git] / libavcodec / snowdec.c
1 /*
2  * Copyright (C) 2004 Michael Niedermayer <michaelni@gmx.at>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20
21 #include "libavutil/intmath.h"
22 #include "libavutil/log.h"
23 #include "libavutil/opt.h"
24 #include "avcodec.h"
25 #include "dsputil.h"
26 #include "snow_dwt.h"
27 #include "internal.h"
28 #include "snow.h"
29
30 #include "rangecoder.h"
31 #include "mathops.h"
32
33 #include "mpegvideo.h"
34 #include "h263.h"
35
36 #undef NDEBUG
37 #include <assert.h>
38
39 static av_always_inline void predict_slice_buffered(SnowContext *s, slice_buffer * sb, IDWTELEM * old_buffer, int plane_index, int add, int mb_y){
40     Plane *p= &s->plane[plane_index];
41     const int mb_w= s->b_width  << s->block_max_depth;
42     const int mb_h= s->b_height << s->block_max_depth;
43     int x, y, mb_x;
44     int block_size = MB_SIZE >> s->block_max_depth;
45     int block_w    = plane_index ? block_size>>s->chroma_h_shift : block_size;
46     int block_h    = plane_index ? block_size>>s->chroma_v_shift : block_size;
47     const uint8_t *obmc  = plane_index ? ff_obmc_tab[s->block_max_depth+s->chroma_h_shift] : ff_obmc_tab[s->block_max_depth];
48     int obmc_stride= plane_index ? (2*block_size)>>s->chroma_h_shift : 2*block_size;
49     int ref_stride= s->current_picture.linesize[plane_index];
50     uint8_t *dst8= s->current_picture.data[plane_index];
51     int w= p->width;
52     int h= p->height;
53
54     if(s->keyframe || (s->avctx->debug&512)){
55         if(mb_y==mb_h)
56             return;
57
58         if(add){
59             for(y=block_h*mb_y; y<FFMIN(h,block_h*(mb_y+1)); y++){
60 //                DWTELEM * line = slice_buffer_get_line(sb, y);
61                 IDWTELEM * line = sb->line[y];
62                 for(x=0; x<w; x++){
63 //                    int v= buf[x + y*w] + (128<<FRAC_BITS) + (1<<(FRAC_BITS-1));
64                     int v= line[x] + (128<<FRAC_BITS) + (1<<(FRAC_BITS-1));
65                     v >>= FRAC_BITS;
66                     if(v&(~255)) v= ~(v>>31);
67                     dst8[x + y*ref_stride]= v;
68                 }
69             }
70         }else{
71             for(y=block_h*mb_y; y<FFMIN(h,block_h*(mb_y+1)); y++){
72 //                DWTELEM * line = slice_buffer_get_line(sb, y);
73                 IDWTELEM * line = sb->line[y];
74                 for(x=0; x<w; x++){
75                     line[x] -= 128 << FRAC_BITS;
76 //                    buf[x + y*w]-= 128<<FRAC_BITS;
77                 }
78             }
79         }
80
81         return;
82     }
83
84     for(mb_x=0; mb_x<=mb_w; mb_x++){
85         add_yblock(s, 1, sb, old_buffer, dst8, obmc,
86                    block_w*mb_x - block_w/2,
87                    block_h*mb_y - block_h/2,
88                    block_w, block_h,
89                    w, h,
90                    w, ref_stride, obmc_stride,
91                    mb_x - 1, mb_y - 1,
92                    add, 0, plane_index);
93     }
94 }
95
96 static inline void decode_subband_slice_buffered(SnowContext *s, SubBand *b, slice_buffer * sb, int start_y, int h, int save_state[1]){
97     const int w= b->width;
98     int y;
99     const int qlog= av_clip(s->qlog + b->qlog, 0, QROOT*16);
100     int qmul= ff_qexp[qlog&(QROOT-1)]<<(qlog>>QSHIFT);
101     int qadd= (s->qbias*qmul)>>QBIAS_SHIFT;
102     int new_index = 0;
103
104     if(b->ibuf == s->spatial_idwt_buffer || s->qlog == LOSSLESS_QLOG){
105         qadd= 0;
106         qmul= 1<<QEXPSHIFT;
107     }
108
109     /* If we are on the second or later slice, restore our index. */
110     if (start_y != 0)
111         new_index = save_state[0];
112
113
114     for(y=start_y; y<h; y++){
115         int x = 0;
116         int v;
117         IDWTELEM * line = slice_buffer_get_line(sb, y * b->stride_line + b->buf_y_offset) + b->buf_x_offset;
118         memset(line, 0, b->width*sizeof(IDWTELEM));
119         v = b->x_coeff[new_index].coeff;
120         x = b->x_coeff[new_index++].x;
121         while(x < w){
122             register int t= ( (v>>1)*qmul + qadd)>>QEXPSHIFT;
123             register int u= -(v&1);
124             line[x] = (t^u) - u;
125
126             v = b->x_coeff[new_index].coeff;
127             x = b->x_coeff[new_index++].x;
128         }
129     }
130
131     /* Save our variables for the next slice. */
132     save_state[0] = new_index;
133
134     return;
135 }
136
137 static int decode_q_branch(SnowContext *s, int level, int x, int y){
138     const int w= s->b_width << s->block_max_depth;
139     const int rem_depth= s->block_max_depth - level;
140     const int index= (x + y*w) << rem_depth;
141     int trx= (x+1)<<rem_depth;
142     const BlockNode *left  = x ? &s->block[index-1] : &null_block;
143     const BlockNode *top   = y ? &s->block[index-w] : &null_block;
144     const BlockNode *tl    = y && x ? &s->block[index-w-1] : left;
145     const BlockNode *tr    = y && trx<w && ((x&1)==0 || level==0) ? &s->block[index-w+(1<<rem_depth)] : tl; //FIXME use lt
146     int s_context= 2*left->level + 2*top->level + tl->level + tr->level;
147     int res;
148
149     if(s->keyframe){
150         set_blocks(s, level, x, y, null_block.color[0], null_block.color[1], null_block.color[2], null_block.mx, null_block.my, null_block.ref, BLOCK_INTRA);
151         return 0;
152     }
153
154     if(level==s->block_max_depth || get_rac(&s->c, &s->block_state[4 + s_context])){
155         int type, mx, my;
156         int l = left->color[0];
157         int cb= left->color[1];
158         int cr= left->color[2];
159         int ref = 0;
160         int ref_context= av_log2(2*left->ref) + av_log2(2*top->ref);
161         int mx_context= av_log2(2*FFABS(left->mx - top->mx)) + 0*av_log2(2*FFABS(tr->mx - top->mx));
162         int my_context= av_log2(2*FFABS(left->my - top->my)) + 0*av_log2(2*FFABS(tr->my - top->my));
163
164         type= get_rac(&s->c, &s->block_state[1 + left->type + top->type]) ? BLOCK_INTRA : 0;
165
166         if(type){
167             pred_mv(s, &mx, &my, 0, left, top, tr);
168             l += get_symbol(&s->c, &s->block_state[32], 1);
169             cb+= get_symbol(&s->c, &s->block_state[64], 1);
170             cr+= get_symbol(&s->c, &s->block_state[96], 1);
171         }else{
172             if(s->ref_frames > 1)
173                 ref= get_symbol(&s->c, &s->block_state[128 + 1024 + 32*ref_context], 0);
174             if (ref >= s->ref_frames) {
175                 av_log(s->avctx, AV_LOG_ERROR, "Invalid ref\n");
176                 return AVERROR_INVALIDDATA;
177             }
178             pred_mv(s, &mx, &my, ref, left, top, tr);
179             mx+= get_symbol(&s->c, &s->block_state[128 + 32*(mx_context + 16*!!ref)], 1);
180             my+= get_symbol(&s->c, &s->block_state[128 + 32*(my_context + 16*!!ref)], 1);
181         }
182         set_blocks(s, level, x, y, l, cb, cr, mx, my, ref, type);
183     }else{
184         if ((res = decode_q_branch(s, level+1, 2*x+0, 2*y+0)) < 0 ||
185             (res = decode_q_branch(s, level+1, 2*x+1, 2*y+0)) < 0 ||
186             (res = decode_q_branch(s, level+1, 2*x+0, 2*y+1)) < 0 ||
187             (res = decode_q_branch(s, level+1, 2*x+1, 2*y+1)) < 0)
188             return res;
189     }
190     return 0;
191 }
192
193 static void dequantize_slice_buffered(SnowContext *s, slice_buffer * sb, SubBand *b, IDWTELEM *src, int stride, int start_y, int end_y){
194     const int w= b->width;
195     const int qlog= av_clip(s->qlog + b->qlog, 0, QROOT*16);
196     const int qmul= ff_qexp[qlog&(QROOT-1)]<<(qlog>>QSHIFT);
197     const int qadd= (s->qbias*qmul)>>QBIAS_SHIFT;
198     int x,y;
199
200     if(s->qlog == LOSSLESS_QLOG) return;
201
202     for(y=start_y; y<end_y; y++){
203 //        DWTELEM * line = slice_buffer_get_line_from_address(sb, src + (y * stride));
204         IDWTELEM * line = slice_buffer_get_line(sb, (y * b->stride_line) + b->buf_y_offset) + b->buf_x_offset;
205         for(x=0; x<w; x++){
206             int i= line[x];
207             if(i<0){
208                 line[x]= -((-i*qmul + qadd)>>(QEXPSHIFT)); //FIXME try different bias
209             }else if(i>0){
210                 line[x]=  (( i*qmul + qadd)>>(QEXPSHIFT));
211             }
212         }
213     }
214 }
215
216 static void correlate_slice_buffered(SnowContext *s, slice_buffer * sb, SubBand *b, IDWTELEM *src, int stride, int inverse, int use_median, int start_y, int end_y){
217     const int w= b->width;
218     int x,y;
219
220     IDWTELEM * line=0; // silence silly "could be used without having been initialized" warning
221     IDWTELEM * prev;
222
223     if (start_y != 0)
224         line = slice_buffer_get_line(sb, ((start_y - 1) * b->stride_line) + b->buf_y_offset) + b->buf_x_offset;
225
226     for(y=start_y; y<end_y; y++){
227         prev = line;
228 //        line = slice_buffer_get_line_from_address(sb, src + (y * stride));
229         line = slice_buffer_get_line(sb, (y * b->stride_line) + b->buf_y_offset) + b->buf_x_offset;
230         for(x=0; x<w; x++){
231             if(x){
232                 if(use_median){
233                     if(y && x+1<w) line[x] += mid_pred(line[x - 1], prev[x], prev[x + 1]);
234                     else  line[x] += line[x - 1];
235                 }else{
236                     if(y) line[x] += mid_pred(line[x - 1], prev[x], line[x - 1] + prev[x] - prev[x - 1]);
237                     else  line[x] += line[x - 1];
238                 }
239             }else{
240                 if(y) line[x] += prev[x];
241             }
242         }
243     }
244 }
245
246 static void decode_qlogs(SnowContext *s){
247     int plane_index, level, orientation;
248
249     for(plane_index=0; plane_index<3; plane_index++){
250         for(level=0; level<s->spatial_decomposition_count; level++){
251             for(orientation=level ? 1:0; orientation<4; orientation++){
252                 int q;
253                 if     (plane_index==2) q= s->plane[1].band[level][orientation].qlog;
254                 else if(orientation==2) q= s->plane[plane_index].band[level][1].qlog;
255                 else                    q= get_symbol(&s->c, s->header_state, 1);
256                 s->plane[plane_index].band[level][orientation].qlog= q;
257             }
258         }
259     }
260 }
261
262 #define GET_S(dst, check) \
263     tmp= get_symbol(&s->c, s->header_state, 0);\
264     if(!(check)){\
265         av_log(s->avctx, AV_LOG_ERROR, "Error " #dst " is %d\n", tmp);\
266         return -1;\
267     }\
268     dst= tmp;
269
270 static int decode_header(SnowContext *s){
271     int plane_index, tmp;
272     uint8_t kstate[32];
273
274     memset(kstate, MID_STATE, sizeof(kstate));
275
276     s->keyframe= get_rac(&s->c, kstate);
277     if(s->keyframe || s->always_reset){
278         ff_snow_reset_contexts(s);
279         s->spatial_decomposition_type=
280         s->qlog=
281         s->qbias=
282         s->mv_scale=
283         s->block_max_depth= 0;
284     }
285     if(s->keyframe){
286         GET_S(s->version, tmp <= 0U)
287         s->always_reset= get_rac(&s->c, s->header_state);
288         s->temporal_decomposition_type= get_symbol(&s->c, s->header_state, 0);
289         s->temporal_decomposition_count= get_symbol(&s->c, s->header_state, 0);
290         GET_S(s->spatial_decomposition_count, 0 < tmp && tmp <= MAX_DECOMPOSITIONS)
291         s->colorspace_type= get_symbol(&s->c, s->header_state, 0);
292         s->chroma_h_shift= get_symbol(&s->c, s->header_state, 0);
293         s->chroma_v_shift= get_symbol(&s->c, s->header_state, 0);
294
295         if(s->chroma_h_shift == 1 && s->chroma_v_shift==1){
296             s->avctx->pix_fmt= AV_PIX_FMT_YUV420P;
297         }else if(s->chroma_h_shift == 0 && s->chroma_v_shift==0){
298             s->avctx->pix_fmt= AV_PIX_FMT_YUV444P;
299         }else if(s->chroma_h_shift == 2 && s->chroma_v_shift==2){
300             s->avctx->pix_fmt= AV_PIX_FMT_YUV410P;
301         } else {
302             av_log(s, AV_LOG_ERROR, "unsupported color subsample mode %d %d\n", s->chroma_h_shift, s->chroma_v_shift);
303             s->chroma_h_shift = s->chroma_v_shift = 1;
304             s->avctx->pix_fmt= AV_PIX_FMT_YUV420P;
305             return AVERROR_INVALIDDATA;
306         }
307
308         s->spatial_scalability= get_rac(&s->c, s->header_state);
309 //        s->rate_scalability= get_rac(&s->c, s->header_state);
310         GET_S(s->max_ref_frames, tmp < (unsigned)MAX_REF_FRAMES)
311         s->max_ref_frames++;
312
313         decode_qlogs(s);
314     }
315
316     if(!s->keyframe){
317         if(get_rac(&s->c, s->header_state)){
318             for(plane_index=0; plane_index<2; plane_index++){
319                 int htaps, i, sum=0;
320                 Plane *p= &s->plane[plane_index];
321                 p->diag_mc= get_rac(&s->c, s->header_state);
322                 htaps= get_symbol(&s->c, s->header_state, 0)*2 + 2;
323                 if((unsigned)htaps > HTAPS_MAX || htaps==0)
324                     return -1;
325                 p->htaps= htaps;
326                 for(i= htaps/2; i; i--){
327                     p->hcoeff[i]= get_symbol(&s->c, s->header_state, 0) * (1-2*(i&1));
328                     sum += p->hcoeff[i];
329                 }
330                 p->hcoeff[0]= 32-sum;
331             }
332             s->plane[2].diag_mc= s->plane[1].diag_mc;
333             s->plane[2].htaps  = s->plane[1].htaps;
334             memcpy(s->plane[2].hcoeff, s->plane[1].hcoeff, sizeof(s->plane[1].hcoeff));
335         }
336         if(get_rac(&s->c, s->header_state)){
337             GET_S(s->spatial_decomposition_count, 0 < tmp && tmp <= MAX_DECOMPOSITIONS)
338             decode_qlogs(s);
339         }
340     }
341
342     s->spatial_decomposition_type+= get_symbol(&s->c, s->header_state, 1);
343     if(s->spatial_decomposition_type > 1U){
344         av_log(s->avctx, AV_LOG_ERROR, "spatial_decomposition_type %d not supported\n", s->spatial_decomposition_type);
345         return -1;
346     }
347     if(FFMIN(s->avctx-> width>>s->chroma_h_shift,
348              s->avctx->height>>s->chroma_v_shift) >> (s->spatial_decomposition_count-1) <= 1){
349         av_log(s->avctx, AV_LOG_ERROR, "spatial_decomposition_count %d too large for size\n", s->spatial_decomposition_count);
350         return -1;
351     }
352
353
354     s->qlog           += get_symbol(&s->c, s->header_state, 1);
355     s->mv_scale       += get_symbol(&s->c, s->header_state, 1);
356     s->qbias          += get_symbol(&s->c, s->header_state, 1);
357     s->block_max_depth+= get_symbol(&s->c, s->header_state, 1);
358     if(s->block_max_depth > 1 || s->block_max_depth < 0){
359         av_log(s->avctx, AV_LOG_ERROR, "block_max_depth= %d is too large\n", s->block_max_depth);
360         s->block_max_depth= 0;
361         return -1;
362     }
363
364     return 0;
365 }
366
367 static av_cold int decode_init(AVCodecContext *avctx)
368 {
369     int ret;
370
371     if ((ret = ff_snow_common_init(avctx)) < 0) {
372         ff_snow_common_end(avctx->priv_data);
373         return ret;
374     }
375
376     return 0;
377 }
378
379 static int decode_blocks(SnowContext *s){
380     int x, y;
381     int w= s->b_width;
382     int h= s->b_height;
383     int res;
384
385     for(y=0; y<h; y++){
386         for(x=0; x<w; x++){
387             if ((res = decode_q_branch(s, 0, x, y)) < 0)
388                 return res;
389         }
390     }
391     return 0;
392 }
393
394 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
395                         AVPacket *avpkt)
396 {
397     const uint8_t *buf = avpkt->data;
398     int buf_size = avpkt->size;
399     SnowContext *s = avctx->priv_data;
400     RangeCoder * const c= &s->c;
401     int bytes_read;
402     AVFrame *picture = data;
403     int level, orientation, plane_index;
404     int res;
405
406     ff_init_range_decoder(c, buf, buf_size);
407     ff_build_rac_states(c, 0.05*(1LL<<32), 256-8);
408
409     s->current_picture.pict_type= AV_PICTURE_TYPE_I; //FIXME I vs. P
410     if(decode_header(s)<0)
411         return -1;
412     if ((res=ff_snow_common_init_after_header(avctx)) < 0)
413         return res;
414
415     // realloc slice buffer for the case that spatial_decomposition_count changed
416     ff_slice_buffer_destroy(&s->sb);
417     if ((res = ff_slice_buffer_init(&s->sb, s->plane[0].height,
418                                     (MB_SIZE >> s->block_max_depth) +
419                                     s->spatial_decomposition_count * 11 + 1,
420                                     s->plane[0].width,
421                                     s->spatial_idwt_buffer)) < 0)
422         return res;
423
424     for(plane_index=0; plane_index<3; plane_index++){
425         Plane *p= &s->plane[plane_index];
426         p->fast_mc= p->diag_mc && p->htaps==6 && p->hcoeff[0]==40
427                                               && p->hcoeff[1]==-10
428                                               && p->hcoeff[2]==2;
429     }
430
431     ff_snow_alloc_blocks(s);
432
433     if(ff_snow_frame_start(s) < 0)
434         return -1;
435     //keyframe flag duplication mess FIXME
436     if(avctx->debug&FF_DEBUG_PICT_INFO)
437         av_log(avctx, AV_LOG_ERROR, "keyframe:%d qlog:%d\n", s->keyframe, s->qlog);
438
439     if ((res = decode_blocks(s)) < 0)
440         return res;
441
442     for(plane_index=0; plane_index<3; plane_index++){
443         Plane *p= &s->plane[plane_index];
444         int w= p->width;
445         int h= p->height;
446         int x, y;
447         int decode_state[MAX_DECOMPOSITIONS][4][1]; /* Stored state info for unpack_coeffs. 1 variable per instance. */
448
449         if(s->avctx->debug&2048){
450             memset(s->spatial_dwt_buffer, 0, sizeof(DWTELEM)*w*h);
451             predict_plane(s, s->spatial_idwt_buffer, plane_index, 1);
452
453             for(y=0; y<h; y++){
454                 for(x=0; x<w; x++){
455                     int v= s->current_picture.data[plane_index][y*s->current_picture.linesize[plane_index] + x];
456                     s->mconly_picture.data[plane_index][y*s->mconly_picture.linesize[plane_index] + x]= v;
457                 }
458             }
459         }
460
461         {
462         for(level=0; level<s->spatial_decomposition_count; level++){
463             for(orientation=level ? 1 : 0; orientation<4; orientation++){
464                 SubBand *b= &p->band[level][orientation];
465                 unpack_coeffs(s, b, b->parent, orientation);
466             }
467         }
468         }
469
470         {
471         const int mb_h= s->b_height << s->block_max_depth;
472         const int block_size = MB_SIZE >> s->block_max_depth;
473         const int block_h    = plane_index ? block_size>>s->chroma_v_shift : block_size;
474         int mb_y;
475         DWTCompose cs[MAX_DECOMPOSITIONS];
476         int yd=0, yq=0;
477         int y;
478         int end_y;
479
480         ff_spatial_idwt_buffered_init(cs, &s->sb, w, h, 1, s->spatial_decomposition_type, s->spatial_decomposition_count);
481         for(mb_y=0; mb_y<=mb_h; mb_y++){
482
483             int slice_starty = block_h*mb_y;
484             int slice_h = block_h*(mb_y+1);
485
486             if (!(s->keyframe || s->avctx->debug&512)){
487                 slice_starty = FFMAX(0, slice_starty - (block_h >> 1));
488                 slice_h -= (block_h >> 1);
489             }
490
491             for(level=0; level<s->spatial_decomposition_count; level++){
492                 for(orientation=level ? 1 : 0; orientation<4; orientation++){
493                     SubBand *b= &p->band[level][orientation];
494                     int start_y;
495                     int end_y;
496                     int our_mb_start = mb_y;
497                     int our_mb_end = (mb_y + 1);
498                     const int extra= 3;
499                     start_y = (mb_y ? ((block_h * our_mb_start) >> (s->spatial_decomposition_count - level)) + s->spatial_decomposition_count - level + extra: 0);
500                     end_y = (((block_h * our_mb_end) >> (s->spatial_decomposition_count - level)) + s->spatial_decomposition_count - level + extra);
501                     if (!(s->keyframe || s->avctx->debug&512)){
502                         start_y = FFMAX(0, start_y - (block_h >> (1+s->spatial_decomposition_count - level)));
503                         end_y = FFMAX(0, end_y - (block_h >> (1+s->spatial_decomposition_count - level)));
504                     }
505                     start_y = FFMIN(b->height, start_y);
506                     end_y = FFMIN(b->height, end_y);
507
508                     if (start_y != end_y){
509                         if (orientation == 0){
510                             SubBand * correlate_band = &p->band[0][0];
511                             int correlate_end_y = FFMIN(b->height, end_y + 1);
512                             int correlate_start_y = FFMIN(b->height, (start_y ? start_y + 1 : 0));
513                             decode_subband_slice_buffered(s, correlate_band, &s->sb, correlate_start_y, correlate_end_y, decode_state[0][0]);
514                             correlate_slice_buffered(s, &s->sb, correlate_band, correlate_band->ibuf, correlate_band->stride, 1, 0, correlate_start_y, correlate_end_y);
515                             dequantize_slice_buffered(s, &s->sb, correlate_band, correlate_band->ibuf, correlate_band->stride, start_y, end_y);
516                         }
517                         else
518                             decode_subband_slice_buffered(s, b, &s->sb, start_y, end_y, decode_state[level][orientation]);
519                     }
520                 }
521             }
522
523             for(; yd<slice_h; yd+=4){
524                 ff_spatial_idwt_buffered_slice(&s->dwt, cs, &s->sb, s->temp_idwt_buffer, w, h, 1, s->spatial_decomposition_type, s->spatial_decomposition_count, yd);
525             }
526
527             if(s->qlog == LOSSLESS_QLOG){
528                 for(; yq<slice_h && yq<h; yq++){
529                     IDWTELEM * line = slice_buffer_get_line(&s->sb, yq);
530                     for(x=0; x<w; x++){
531                         line[x] <<= FRAC_BITS;
532                     }
533                 }
534             }
535
536             predict_slice_buffered(s, &s->sb, s->spatial_idwt_buffer, plane_index, 1, mb_y);
537
538             y = FFMIN(p->height, slice_starty);
539             end_y = FFMIN(p->height, slice_h);
540             while(y < end_y)
541                 ff_slice_buffer_release(&s->sb, y++);
542         }
543
544         ff_slice_buffer_flush(&s->sb);
545         }
546
547     }
548
549     emms_c();
550
551     ff_snow_release_buffer(avctx);
552
553     if(!(s->avctx->debug&2048))
554         av_frame_ref(picture, &s->current_picture);
555     else
556         av_frame_ref(picture, &s->mconly_picture);
557
558     *got_frame = 1;
559
560     bytes_read= c->bytestream - c->bytestream_start;
561     if(bytes_read ==0) av_log(s->avctx, AV_LOG_ERROR, "error at end of frame\n"); //FIXME
562
563     return bytes_read;
564 }
565
566 static av_cold int decode_end(AVCodecContext *avctx)
567 {
568     SnowContext *s = avctx->priv_data;
569
570     ff_slice_buffer_destroy(&s->sb);
571
572     ff_snow_common_end(s);
573
574     return 0;
575 }
576
577 AVCodec ff_snow_decoder = {
578     .name           = "snow",
579     .type           = AVMEDIA_TYPE_VIDEO,
580     .id             = AV_CODEC_ID_SNOW,
581     .priv_data_size = sizeof(SnowContext),
582     .init           = decode_init,
583     .close          = decode_end,
584     .decode         = decode_frame,
585     .capabilities   = CODEC_CAP_DR1 /*| CODEC_CAP_DRAW_HORIZ_BAND*/,
586     .long_name      = NULL_IF_CONFIG_SMALL("Snow"),
587 };