Libav 0.7.1
libavcodec/vp56.c
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00001 
00024 #include "avcodec.h"
00025 #include "bytestream.h"
00026 
00027 #include "vp56.h"
00028 #include "vp56data.h"
00029 
00030 
00031 void ff_vp56_init_dequant(VP56Context *s, int quantizer)
00032 {
00033     s->quantizer = quantizer;
00034     s->dequant_dc = vp56_dc_dequant[quantizer] << 2;
00035     s->dequant_ac = vp56_ac_dequant[quantizer] << 2;
00036     memset(s->qscale_table, quantizer, s->mb_width);
00037 }
00038 
00039 static int vp56_get_vectors_predictors(VP56Context *s, int row, int col,
00040                                        VP56Frame ref_frame)
00041 {
00042     int nb_pred = 0;
00043     VP56mv vect[2] = {{0,0}, {0,0}};
00044     int pos, offset;
00045     VP56mv mvp;
00046 
00047     for (pos=0; pos<12; pos++) {
00048         mvp.x = col + vp56_candidate_predictor_pos[pos][0];
00049         mvp.y = row + vp56_candidate_predictor_pos[pos][1];
00050         if (mvp.x < 0 || mvp.x >= s->mb_width ||
00051             mvp.y < 0 || mvp.y >= s->mb_height)
00052             continue;
00053         offset = mvp.x + s->mb_width*mvp.y;
00054 
00055         if (vp56_reference_frame[s->macroblocks[offset].type] != ref_frame)
00056             continue;
00057         if ((s->macroblocks[offset].mv.x == vect[0].x &&
00058              s->macroblocks[offset].mv.y == vect[0].y) ||
00059             (s->macroblocks[offset].mv.x == 0 &&
00060              s->macroblocks[offset].mv.y == 0))
00061             continue;
00062 
00063         vect[nb_pred++] = s->macroblocks[offset].mv;
00064         if (nb_pred > 1) {
00065             nb_pred = -1;
00066             break;
00067         }
00068         s->vector_candidate_pos = pos;
00069     }
00070 
00071     s->vector_candidate[0] = vect[0];
00072     s->vector_candidate[1] = vect[1];
00073 
00074     return nb_pred+1;
00075 }
00076 
00077 static void vp56_parse_mb_type_models(VP56Context *s)
00078 {
00079     VP56RangeCoder *c = &s->c;
00080     VP56Model *model = s->modelp;
00081     int i, ctx, type;
00082 
00083     for (ctx=0; ctx<3; ctx++) {
00084         if (vp56_rac_get_prob(c, 174)) {
00085             int idx = vp56_rac_gets(c, 4);
00086             memcpy(model->mb_types_stats[ctx],
00087                    vp56_pre_def_mb_type_stats[idx][ctx],
00088                    sizeof(model->mb_types_stats[ctx]));
00089         }
00090         if (vp56_rac_get_prob(c, 254)) {
00091             for (type=0; type<10; type++) {
00092                 for(i=0; i<2; i++) {
00093                     if (vp56_rac_get_prob(c, 205)) {
00094                         int delta, sign = vp56_rac_get(c);
00095 
00096                         delta = vp56_rac_get_tree(c, vp56_pmbtm_tree,
00097                                                   vp56_mb_type_model_model);
00098                         if (!delta)
00099                             delta = 4 * vp56_rac_gets(c, 7);
00100                         model->mb_types_stats[ctx][type][i] += (delta ^ -sign) + sign;
00101                     }
00102                 }
00103             }
00104         }
00105     }
00106 
00107     /* compute MB type probability tables based on previous MB type */
00108     for (ctx=0; ctx<3; ctx++) {
00109         int p[10];
00110 
00111         for (type=0; type<10; type++)
00112             p[type] = 100 * model->mb_types_stats[ctx][type][1];
00113 
00114         for (type=0; type<10; type++) {
00115             int p02, p34, p0234, p17, p56, p89, p5689, p156789;
00116 
00117             /* conservative MB type probability */
00118             model->mb_type[ctx][type][0] = 255 - (255 * model->mb_types_stats[ctx][type][0]) / (1 + model->mb_types_stats[ctx][type][0] + model->mb_types_stats[ctx][type][1]);
00119 
00120             p[type] = 0;    /* same MB type => weight is null */
00121 
00122             /* binary tree parsing probabilities */
00123             p02 = p[0] + p[2];
00124             p34 = p[3] + p[4];
00125             p0234 = p02 + p34;
00126             p17 = p[1] + p[7];
00127             p56 = p[5] + p[6];
00128             p89 = p[8] + p[9];
00129             p5689 = p56 + p89;
00130             p156789 = p17 + p5689;
00131 
00132             model->mb_type[ctx][type][1] = 1 + 255 * p0234/(1+p0234+p156789);
00133             model->mb_type[ctx][type][2] = 1 + 255 * p02  / (1+p0234);
00134             model->mb_type[ctx][type][3] = 1 + 255 * p17  / (1+p156789);
00135             model->mb_type[ctx][type][4] = 1 + 255 * p[0] / (1+p02);
00136             model->mb_type[ctx][type][5] = 1 + 255 * p[3] / (1+p34);
00137             model->mb_type[ctx][type][6] = 1 + 255 * p[1] / (1+p17);
00138             model->mb_type[ctx][type][7] = 1 + 255 * p56  / (1+p5689);
00139             model->mb_type[ctx][type][8] = 1 + 255 * p[5] / (1+p56);
00140             model->mb_type[ctx][type][9] = 1 + 255 * p[8] / (1+p89);
00141 
00142             /* restore initial value */
00143             p[type] = 100 * model->mb_types_stats[ctx][type][1];
00144         }
00145     }
00146 }
00147 
00148 static VP56mb vp56_parse_mb_type(VP56Context *s,
00149                                  VP56mb prev_type, int ctx)
00150 {
00151     uint8_t *mb_type_model = s->modelp->mb_type[ctx][prev_type];
00152     VP56RangeCoder *c = &s->c;
00153 
00154     if (vp56_rac_get_prob(c, mb_type_model[0]))
00155         return prev_type;
00156     else
00157         return vp56_rac_get_tree(c, vp56_pmbt_tree, mb_type_model);
00158 }
00159 
00160 static void vp56_decode_4mv(VP56Context *s, int row, int col)
00161 {
00162     VP56mv mv = {0,0};
00163     int type[4];
00164     int b;
00165 
00166     /* parse each block type */
00167     for (b=0; b<4; b++) {
00168         type[b] = vp56_rac_gets(&s->c, 2);
00169         if (type[b])
00170             type[b]++;  /* only returns 0, 2, 3 or 4 (all INTER_PF) */
00171     }
00172 
00173     /* get vectors */
00174     for (b=0; b<4; b++) {
00175         switch (type[b]) {
00176             case VP56_MB_INTER_NOVEC_PF:
00177                 s->mv[b] = (VP56mv) {0,0};
00178                 break;
00179             case VP56_MB_INTER_DELTA_PF:
00180                 s->parse_vector_adjustment(s, &s->mv[b]);
00181                 break;
00182             case VP56_MB_INTER_V1_PF:
00183                 s->mv[b] = s->vector_candidate[0];
00184                 break;
00185             case VP56_MB_INTER_V2_PF:
00186                 s->mv[b] = s->vector_candidate[1];
00187                 break;
00188         }
00189         mv.x += s->mv[b].x;
00190         mv.y += s->mv[b].y;
00191     }
00192 
00193     /* this is the one selected for the whole MB for prediction */
00194     s->macroblocks[row * s->mb_width + col].mv = s->mv[3];
00195 
00196     /* chroma vectors are average luma vectors */
00197     if (s->avctx->codec->id == CODEC_ID_VP5) {
00198         s->mv[4].x = s->mv[5].x = RSHIFT(mv.x,2);
00199         s->mv[4].y = s->mv[5].y = RSHIFT(mv.y,2);
00200     } else {
00201         s->mv[4] = s->mv[5] = (VP56mv) {mv.x/4, mv.y/4};
00202     }
00203 }
00204 
00205 static VP56mb vp56_decode_mv(VP56Context *s, int row, int col)
00206 {
00207     VP56mv *mv, vect = {0,0};
00208     int ctx, b;
00209 
00210     ctx = vp56_get_vectors_predictors(s, row, col, VP56_FRAME_PREVIOUS);
00211     s->mb_type = vp56_parse_mb_type(s, s->mb_type, ctx);
00212     s->macroblocks[row * s->mb_width + col].type = s->mb_type;
00213 
00214     switch (s->mb_type) {
00215         case VP56_MB_INTER_V1_PF:
00216             mv = &s->vector_candidate[0];
00217             break;
00218 
00219         case VP56_MB_INTER_V2_PF:
00220             mv = &s->vector_candidate[1];
00221             break;
00222 
00223         case VP56_MB_INTER_V1_GF:
00224             vp56_get_vectors_predictors(s, row, col, VP56_FRAME_GOLDEN);
00225             mv = &s->vector_candidate[0];
00226             break;
00227 
00228         case VP56_MB_INTER_V2_GF:
00229             vp56_get_vectors_predictors(s, row, col, VP56_FRAME_GOLDEN);
00230             mv = &s->vector_candidate[1];
00231             break;
00232 
00233         case VP56_MB_INTER_DELTA_PF:
00234             s->parse_vector_adjustment(s, &vect);
00235             mv = &vect;
00236             break;
00237 
00238         case VP56_MB_INTER_DELTA_GF:
00239             vp56_get_vectors_predictors(s, row, col, VP56_FRAME_GOLDEN);
00240             s->parse_vector_adjustment(s, &vect);
00241             mv = &vect;
00242             break;
00243 
00244         case VP56_MB_INTER_4V:
00245             vp56_decode_4mv(s, row, col);
00246             return s->mb_type;
00247 
00248         default:
00249             mv = &vect;
00250             break;
00251     }
00252 
00253     s->macroblocks[row*s->mb_width + col].mv = *mv;
00254 
00255     /* same vector for all blocks */
00256     for (b=0; b<6; b++)
00257         s->mv[b] = *mv;
00258 
00259     return s->mb_type;
00260 }
00261 
00262 static void vp56_add_predictors_dc(VP56Context *s, VP56Frame ref_frame)
00263 {
00264     int idx = s->scantable.permutated[0];
00265     int b;
00266 
00267     for (b=0; b<6; b++) {
00268         VP56RefDc *ab = &s->above_blocks[s->above_block_idx[b]];
00269         VP56RefDc *lb = &s->left_block[vp56_b6to4[b]];
00270         int count = 0;
00271         int dc = 0;
00272         int i;
00273 
00274         if (ref_frame == lb->ref_frame) {
00275             dc += lb->dc_coeff;
00276             count++;
00277         }
00278         if (ref_frame == ab->ref_frame) {
00279             dc += ab->dc_coeff;
00280             count++;
00281         }
00282         if (s->avctx->codec->id == CODEC_ID_VP5)
00283             for (i=0; i<2; i++)
00284                 if (count < 2 && ref_frame == ab[-1+2*i].ref_frame) {
00285                     dc += ab[-1+2*i].dc_coeff;
00286                     count++;
00287                 }
00288         if (count == 0)
00289             dc = s->prev_dc[vp56_b2p[b]][ref_frame];
00290         else if (count == 2)
00291             dc /= 2;
00292 
00293         s->block_coeff[b][idx] += dc;
00294         s->prev_dc[vp56_b2p[b]][ref_frame] = s->block_coeff[b][idx];
00295         ab->dc_coeff = s->block_coeff[b][idx];
00296         ab->ref_frame = ref_frame;
00297         lb->dc_coeff = s->block_coeff[b][idx];
00298         lb->ref_frame = ref_frame;
00299         s->block_coeff[b][idx] *= s->dequant_dc;
00300     }
00301 }
00302 
00303 static void vp56_deblock_filter(VP56Context *s, uint8_t *yuv,
00304                                 int stride, int dx, int dy)
00305 {
00306     int t = vp56_filter_threshold[s->quantizer];
00307     if (dx)  s->vp56dsp.edge_filter_hor(yuv +         10-dx , stride, t);
00308     if (dy)  s->vp56dsp.edge_filter_ver(yuv + stride*(10-dy), stride, t);
00309 }
00310 
00311 static void vp56_mc(VP56Context *s, int b, int plane, uint8_t *src,
00312                     int stride, int x, int y)
00313 {
00314     uint8_t *dst=s->framep[VP56_FRAME_CURRENT]->data[plane]+s->block_offset[b];
00315     uint8_t *src_block;
00316     int src_offset;
00317     int overlap_offset = 0;
00318     int mask = s->vp56_coord_div[b] - 1;
00319     int deblock_filtering = s->deblock_filtering;
00320     int dx;
00321     int dy;
00322 
00323     if (s->avctx->skip_loop_filter >= AVDISCARD_ALL ||
00324         (s->avctx->skip_loop_filter >= AVDISCARD_NONKEY
00325          && !s->framep[VP56_FRAME_CURRENT]->key_frame))
00326         deblock_filtering = 0;
00327 
00328     dx = s->mv[b].x / s->vp56_coord_div[b];
00329     dy = s->mv[b].y / s->vp56_coord_div[b];
00330 
00331     if (b >= 4) {
00332         x /= 2;
00333         y /= 2;
00334     }
00335     x += dx - 2;
00336     y += dy - 2;
00337 
00338     if (x<0 || x+12>=s->plane_width[plane] ||
00339         y<0 || y+12>=s->plane_height[plane]) {
00340         s->dsp.emulated_edge_mc(s->edge_emu_buffer,
00341                             src + s->block_offset[b] + (dy-2)*stride + (dx-2),
00342                             stride, 12, 12, x, y,
00343                             s->plane_width[plane],
00344                             s->plane_height[plane]);
00345         src_block = s->edge_emu_buffer;
00346         src_offset = 2 + 2*stride;
00347     } else if (deblock_filtering) {
00348         /* only need a 12x12 block, but there is no such dsp function, */
00349         /* so copy a 16x12 block */
00350         s->dsp.put_pixels_tab[0][0](s->edge_emu_buffer,
00351                                     src + s->block_offset[b] + (dy-2)*stride + (dx-2),
00352                                     stride, 12);
00353         src_block = s->edge_emu_buffer;
00354         src_offset = 2 + 2*stride;
00355     } else {
00356         src_block = src;
00357         src_offset = s->block_offset[b] + dy*stride + dx;
00358     }
00359 
00360     if (deblock_filtering)
00361         vp56_deblock_filter(s, src_block, stride, dx&7, dy&7);
00362 
00363     if (s->mv[b].x & mask)
00364         overlap_offset += (s->mv[b].x > 0) ? 1 : -1;
00365     if (s->mv[b].y & mask)
00366         overlap_offset += (s->mv[b].y > 0) ? stride : -stride;
00367 
00368     if (overlap_offset) {
00369         if (s->filter)
00370             s->filter(s, dst, src_block, src_offset, src_offset+overlap_offset,
00371                       stride, s->mv[b], mask, s->filter_selection, b<4);
00372         else
00373             s->dsp.put_no_rnd_pixels_l2[1](dst, src_block+src_offset,
00374                                            src_block+src_offset+overlap_offset,
00375                                            stride, 8);
00376     } else {
00377         s->dsp.put_pixels_tab[1][0](dst, src_block+src_offset, stride, 8);
00378     }
00379 }
00380 
00381 static void vp56_decode_mb(VP56Context *s, int row, int col, int is_alpha)
00382 {
00383     AVFrame *frame_current, *frame_ref;
00384     VP56mb mb_type;
00385     VP56Frame ref_frame;
00386     int b, ab, b_max, plane, off;
00387 
00388     if (s->framep[VP56_FRAME_CURRENT]->key_frame)
00389         mb_type = VP56_MB_INTRA;
00390     else
00391         mb_type = vp56_decode_mv(s, row, col);
00392     ref_frame = vp56_reference_frame[mb_type];
00393 
00394     s->dsp.clear_blocks(*s->block_coeff);
00395 
00396     s->parse_coeff(s);
00397 
00398     vp56_add_predictors_dc(s, ref_frame);
00399 
00400     frame_current = s->framep[VP56_FRAME_CURRENT];
00401     frame_ref = s->framep[ref_frame];
00402     if (mb_type != VP56_MB_INTRA && !frame_ref->data[0])
00403         return;
00404 
00405     ab = 6*is_alpha;
00406     b_max = 6 - 2*is_alpha;
00407 
00408     switch (mb_type) {
00409         case VP56_MB_INTRA:
00410             for (b=0; b<b_max; b++) {
00411                 plane = vp56_b2p[b+ab];
00412                 s->dsp.idct_put(frame_current->data[plane] + s->block_offset[b],
00413                                 s->stride[plane], s->block_coeff[b]);
00414             }
00415             break;
00416 
00417         case VP56_MB_INTER_NOVEC_PF:
00418         case VP56_MB_INTER_NOVEC_GF:
00419             for (b=0; b<b_max; b++) {
00420                 plane = vp56_b2p[b+ab];
00421                 off = s->block_offset[b];
00422                 s->dsp.put_pixels_tab[1][0](frame_current->data[plane] + off,
00423                                             frame_ref->data[plane] + off,
00424                                             s->stride[plane], 8);
00425                 s->dsp.idct_add(frame_current->data[plane] + off,
00426                                 s->stride[plane], s->block_coeff[b]);
00427             }
00428             break;
00429 
00430         case VP56_MB_INTER_DELTA_PF:
00431         case VP56_MB_INTER_V1_PF:
00432         case VP56_MB_INTER_V2_PF:
00433         case VP56_MB_INTER_DELTA_GF:
00434         case VP56_MB_INTER_4V:
00435         case VP56_MB_INTER_V1_GF:
00436         case VP56_MB_INTER_V2_GF:
00437             for (b=0; b<b_max; b++) {
00438                 int x_off = b==1 || b==3 ? 8 : 0;
00439                 int y_off = b==2 || b==3 ? 8 : 0;
00440                 plane = vp56_b2p[b+ab];
00441                 vp56_mc(s, b, plane, frame_ref->data[plane], s->stride[plane],
00442                         16*col+x_off, 16*row+y_off);
00443                 s->dsp.idct_add(frame_current->data[plane] + s->block_offset[b],
00444                                 s->stride[plane], s->block_coeff[b]);
00445             }
00446             break;
00447     }
00448 }
00449 
00450 static int vp56_size_changed(AVCodecContext *avctx)
00451 {
00452     VP56Context *s = avctx->priv_data;
00453     int stride = s->framep[VP56_FRAME_CURRENT]->linesize[0];
00454     int i;
00455 
00456     s->plane_width[0]  = s->plane_width[3]  = avctx->coded_width;
00457     s->plane_width[1]  = s->plane_width[2]  = avctx->coded_width/2;
00458     s->plane_height[0] = s->plane_height[3] = avctx->coded_height;
00459     s->plane_height[1] = s->plane_height[2] = avctx->coded_height/2;
00460 
00461     for (i=0; i<4; i++)
00462         s->stride[i] = s->flip * s->framep[VP56_FRAME_CURRENT]->linesize[i];
00463 
00464     s->mb_width  = (avctx->coded_width +15) / 16;
00465     s->mb_height = (avctx->coded_height+15) / 16;
00466 
00467     if (s->mb_width > 1000 || s->mb_height > 1000) {
00468         avcodec_set_dimensions(avctx, 0, 0);
00469         av_log(avctx, AV_LOG_ERROR, "picture too big\n");
00470         return -1;
00471     }
00472 
00473     s->qscale_table = av_realloc(s->qscale_table, s->mb_width);
00474     s->above_blocks = av_realloc(s->above_blocks,
00475                                  (4*s->mb_width+6) * sizeof(*s->above_blocks));
00476     s->macroblocks = av_realloc(s->macroblocks,
00477                                 s->mb_width*s->mb_height*sizeof(*s->macroblocks));
00478     av_free(s->edge_emu_buffer_alloc);
00479     s->edge_emu_buffer_alloc = av_malloc(16*stride);
00480     s->edge_emu_buffer = s->edge_emu_buffer_alloc;
00481     if (s->flip < 0)
00482         s->edge_emu_buffer += 15 * stride;
00483 
00484     return 0;
00485 }
00486 
00487 int ff_vp56_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
00488                          AVPacket *avpkt)
00489 {
00490     const uint8_t *buf = avpkt->data;
00491     VP56Context *s = avctx->priv_data;
00492     AVFrame *const p = s->framep[VP56_FRAME_CURRENT];
00493     int remaining_buf_size = avpkt->size;
00494     int is_alpha, av_uninit(alpha_offset);
00495 
00496     if (s->has_alpha) {
00497         if (remaining_buf_size < 3)
00498             return -1;
00499         alpha_offset = bytestream_get_be24(&buf);
00500         remaining_buf_size -= 3;
00501         if (remaining_buf_size < alpha_offset)
00502             return -1;
00503     }
00504 
00505     for (is_alpha=0; is_alpha < 1+s->has_alpha; is_alpha++) {
00506         int mb_row, mb_col, mb_row_flip, mb_offset = 0;
00507         int block, y, uv, stride_y, stride_uv;
00508         int golden_frame = 0;
00509         int res;
00510 
00511         s->modelp = &s->models[is_alpha];
00512 
00513         res = s->parse_header(s, buf, remaining_buf_size, &golden_frame);
00514         if (!res)
00515             return -1;
00516 
00517         if (res == 2) {
00518             int i;
00519             for (i = 0; i < 4; i++) {
00520                 if (s->frames[i].data[0])
00521                     avctx->release_buffer(avctx, &s->frames[i]);
00522             }
00523             if (is_alpha) {
00524                 avcodec_set_dimensions(avctx, 0, 0);
00525                 return -1;
00526             }
00527         }
00528 
00529         if (!is_alpha) {
00530             p->reference = 1;
00531             if (avctx->get_buffer(avctx, p) < 0) {
00532                 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00533                 return -1;
00534             }
00535 
00536             if (res == 2)
00537                 if (vp56_size_changed(avctx)) {
00538                     avctx->release_buffer(avctx, p);
00539                     return -1;
00540                 }
00541         }
00542 
00543         if (p->key_frame) {
00544             p->pict_type = AV_PICTURE_TYPE_I;
00545             s->default_models_init(s);
00546             for (block=0; block<s->mb_height*s->mb_width; block++)
00547                 s->macroblocks[block].type = VP56_MB_INTRA;
00548         } else {
00549             p->pict_type = AV_PICTURE_TYPE_P;
00550             vp56_parse_mb_type_models(s);
00551             s->parse_vector_models(s);
00552             s->mb_type = VP56_MB_INTER_NOVEC_PF;
00553         }
00554 
00555         if (s->parse_coeff_models(s))
00556             goto next;
00557 
00558         memset(s->prev_dc, 0, sizeof(s->prev_dc));
00559         s->prev_dc[1][VP56_FRAME_CURRENT] = 128;
00560         s->prev_dc[2][VP56_FRAME_CURRENT] = 128;
00561 
00562         for (block=0; block < 4*s->mb_width+6; block++) {
00563             s->above_blocks[block].ref_frame = VP56_FRAME_NONE;
00564             s->above_blocks[block].dc_coeff = 0;
00565             s->above_blocks[block].not_null_dc = 0;
00566         }
00567         s->above_blocks[2*s->mb_width + 2].ref_frame = VP56_FRAME_CURRENT;
00568         s->above_blocks[3*s->mb_width + 4].ref_frame = VP56_FRAME_CURRENT;
00569 
00570         stride_y  = p->linesize[0];
00571         stride_uv = p->linesize[1];
00572 
00573         if (s->flip < 0)
00574             mb_offset = 7;
00575 
00576         /* main macroblocks loop */
00577         for (mb_row=0; mb_row<s->mb_height; mb_row++) {
00578             if (s->flip < 0)
00579                 mb_row_flip = s->mb_height - mb_row - 1;
00580             else
00581                 mb_row_flip = mb_row;
00582 
00583             for (block=0; block<4; block++) {
00584                 s->left_block[block].ref_frame = VP56_FRAME_NONE;
00585                 s->left_block[block].dc_coeff = 0;
00586                 s->left_block[block].not_null_dc = 0;
00587             }
00588             memset(s->coeff_ctx, 0, sizeof(s->coeff_ctx));
00589             memset(s->coeff_ctx_last, 24, sizeof(s->coeff_ctx_last));
00590 
00591             s->above_block_idx[0] = 1;
00592             s->above_block_idx[1] = 2;
00593             s->above_block_idx[2] = 1;
00594             s->above_block_idx[3] = 2;
00595             s->above_block_idx[4] = 2*s->mb_width + 2 + 1;
00596             s->above_block_idx[5] = 3*s->mb_width + 4 + 1;
00597 
00598             s->block_offset[s->frbi] = (mb_row_flip*16 + mb_offset) * stride_y;
00599             s->block_offset[s->srbi] = s->block_offset[s->frbi] + 8*stride_y;
00600             s->block_offset[1] = s->block_offset[0] + 8;
00601             s->block_offset[3] = s->block_offset[2] + 8;
00602             s->block_offset[4] = (mb_row_flip*8 + mb_offset) * stride_uv;
00603             s->block_offset[5] = s->block_offset[4];
00604 
00605             for (mb_col=0; mb_col<s->mb_width; mb_col++) {
00606                 vp56_decode_mb(s, mb_row, mb_col, is_alpha);
00607 
00608                 for (y=0; y<4; y++) {
00609                     s->above_block_idx[y] += 2;
00610                     s->block_offset[y] += 16;
00611                 }
00612 
00613                 for (uv=4; uv<6; uv++) {
00614                     s->above_block_idx[uv] += 1;
00615                     s->block_offset[uv] += 8;
00616                 }
00617             }
00618         }
00619 
00620     next:
00621         if (p->key_frame || golden_frame) {
00622             if (s->framep[VP56_FRAME_GOLDEN]->data[0] &&
00623                 s->framep[VP56_FRAME_GOLDEN] != s->framep[VP56_FRAME_GOLDEN2])
00624                 avctx->release_buffer(avctx, s->framep[VP56_FRAME_GOLDEN]);
00625             s->framep[VP56_FRAME_GOLDEN] = p;
00626         }
00627 
00628         if (s->has_alpha) {
00629             FFSWAP(AVFrame *, s->framep[VP56_FRAME_GOLDEN],
00630                               s->framep[VP56_FRAME_GOLDEN2]);
00631             buf += alpha_offset;
00632             remaining_buf_size -= alpha_offset;
00633         }
00634     }
00635 
00636     if (s->framep[VP56_FRAME_PREVIOUS] == s->framep[VP56_FRAME_GOLDEN] ||
00637         s->framep[VP56_FRAME_PREVIOUS] == s->framep[VP56_FRAME_GOLDEN2]) {
00638         if (s->framep[VP56_FRAME_UNUSED] != s->framep[VP56_FRAME_GOLDEN] &&
00639             s->framep[VP56_FRAME_UNUSED] != s->framep[VP56_FRAME_GOLDEN2])
00640             FFSWAP(AVFrame *, s->framep[VP56_FRAME_PREVIOUS],
00641                               s->framep[VP56_FRAME_UNUSED]);
00642         else
00643             FFSWAP(AVFrame *, s->framep[VP56_FRAME_PREVIOUS],
00644                               s->framep[VP56_FRAME_UNUSED2]);
00645     } else if (s->framep[VP56_FRAME_PREVIOUS]->data[0])
00646         avctx->release_buffer(avctx, s->framep[VP56_FRAME_PREVIOUS]);
00647     FFSWAP(AVFrame *, s->framep[VP56_FRAME_CURRENT],
00648                       s->framep[VP56_FRAME_PREVIOUS]);
00649 
00650     p->qstride = 0;
00651     p->qscale_table = s->qscale_table;
00652     p->qscale_type = FF_QSCALE_TYPE_VP56;
00653     *(AVFrame*)data = *p;
00654     *data_size = sizeof(AVFrame);
00655 
00656     return avpkt->size;
00657 }
00658 
00659 av_cold void ff_vp56_init(AVCodecContext *avctx, int flip, int has_alpha)
00660 {
00661     VP56Context *s = avctx->priv_data;
00662     int i;
00663 
00664     s->avctx = avctx;
00665     avctx->pix_fmt = has_alpha ? PIX_FMT_YUVA420P : PIX_FMT_YUV420P;
00666 
00667     if (avctx->idct_algo == FF_IDCT_AUTO)
00668         avctx->idct_algo = FF_IDCT_VP3;
00669     dsputil_init(&s->dsp, avctx);
00670     ff_vp56dsp_init(&s->vp56dsp, avctx->codec->id);
00671     ff_init_scantable(s->dsp.idct_permutation, &s->scantable,ff_zigzag_direct);
00672 
00673     for (i=0; i<4; i++)
00674         s->framep[i] = &s->frames[i];
00675     s->framep[VP56_FRAME_UNUSED] = s->framep[VP56_FRAME_GOLDEN];
00676     s->framep[VP56_FRAME_UNUSED2] = s->framep[VP56_FRAME_GOLDEN2];
00677     s->edge_emu_buffer_alloc = NULL;
00678 
00679     s->above_blocks = NULL;
00680     s->macroblocks = NULL;
00681     s->quantizer = -1;
00682     s->deblock_filtering = 1;
00683 
00684     s->filter = NULL;
00685 
00686     s->has_alpha = has_alpha;
00687     if (flip) {
00688         s->flip = -1;
00689         s->frbi = 2;
00690         s->srbi = 0;
00691     } else {
00692         s->flip = 1;
00693         s->frbi = 0;
00694         s->srbi = 2;
00695     }
00696 }
00697 
00698 av_cold int ff_vp56_free(AVCodecContext *avctx)
00699 {
00700     VP56Context *s = avctx->priv_data;
00701 
00702     av_freep(&s->qscale_table);
00703     av_freep(&s->above_blocks);
00704     av_freep(&s->macroblocks);
00705     av_freep(&s->edge_emu_buffer_alloc);
00706     if (s->framep[VP56_FRAME_GOLDEN]->data[0])
00707         avctx->release_buffer(avctx, s->framep[VP56_FRAME_GOLDEN]);
00708     if (s->framep[VP56_FRAME_GOLDEN2]->data[0])
00709         avctx->release_buffer(avctx, s->framep[VP56_FRAME_GOLDEN2]);
00710     if (s->framep[VP56_FRAME_PREVIOUS]->data[0])
00711         avctx->release_buffer(avctx, s->framep[VP56_FRAME_PREVIOUS]);
00712     return 0;
00713 }