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1 /*
2  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #include "vpx_config.h"
12 #include "vp8_rtcd.h"
13 #include "./vpx_scale_rtcd.h"
14 #include "onyxd_int.h"
15 #include "vp8/common/header.h"
16 #include "vp8/common/reconintra4x4.h"
17 #include "vp8/common/reconinter.h"
18 #include "detokenize.h"
19 #include "vp8/common/common.h"
20 #include "vp8/common/invtrans.h"
21 #include "vp8/common/alloccommon.h"
22 #include "vp8/common/entropymode.h"
23 #include "vp8/common/quant_common.h"
24 #include "vpx_scale/vpx_scale.h"
25 #include "vp8/common/reconintra.h"
26 #include "vp8/common/setupintrarecon.h"
27 
28 #include "decodemv.h"
29 #include "vp8/common/extend.h"
30 #if CONFIG_ERROR_CONCEALMENT
31 #include "error_concealment.h"
32 #endif
33 #include "vpx_mem/vpx_mem.h"
34 #include "vp8/common/threading.h"
35 #include "decoderthreading.h"
36 #include "dboolhuff.h"
37 #include "vpx_dsp/vpx_dsp_common.h"
38 
39 #include <assert.h>
40 #include <stdio.h>
41 
vp8cx_init_de_quantizer(VP8D_COMP * pbi)42 void vp8cx_init_de_quantizer(VP8D_COMP *pbi) {
43   int Q;
44   VP8_COMMON *const pc = &pbi->common;
45 
46   for (Q = 0; Q < QINDEX_RANGE; ++Q) {
47     pc->Y1dequant[Q][0] = (short)vp8_dc_quant(Q, pc->y1dc_delta_q);
48     pc->Y2dequant[Q][0] = (short)vp8_dc2quant(Q, pc->y2dc_delta_q);
49     pc->UVdequant[Q][0] = (short)vp8_dc_uv_quant(Q, pc->uvdc_delta_q);
50 
51     pc->Y1dequant[Q][1] = (short)vp8_ac_yquant(Q);
52     pc->Y2dequant[Q][1] = (short)vp8_ac2quant(Q, pc->y2ac_delta_q);
53     pc->UVdequant[Q][1] = (short)vp8_ac_uv_quant(Q, pc->uvac_delta_q);
54   }
55 }
56 
vp8_mb_init_dequantizer(VP8D_COMP * pbi,MACROBLOCKD * xd)57 void vp8_mb_init_dequantizer(VP8D_COMP *pbi, MACROBLOCKD *xd) {
58   int i;
59   int QIndex;
60   MB_MODE_INFO *mbmi = &xd->mode_info_context->mbmi;
61   VP8_COMMON *const pc = &pbi->common;
62 
63   /* Decide whether to use the default or alternate baseline Q value. */
64   if (xd->segmentation_enabled) {
65     /* Abs Value */
66     if (xd->mb_segement_abs_delta == SEGMENT_ABSDATA) {
67       QIndex = xd->segment_feature_data[MB_LVL_ALT_Q][mbmi->segment_id];
68 
69       /* Delta Value */
70     } else {
71       QIndex = pc->base_qindex +
72                xd->segment_feature_data[MB_LVL_ALT_Q][mbmi->segment_id];
73     }
74 
75     QIndex = (QIndex >= 0) ? ((QIndex <= MAXQ) ? QIndex : MAXQ)
76                            : 0; /* Clamp to valid range */
77   } else {
78     QIndex = pc->base_qindex;
79   }
80 
81   /* Set up the macroblock dequant constants */
82   xd->dequant_y1_dc[0] = 1;
83   xd->dequant_y1[0] = pc->Y1dequant[QIndex][0];
84   xd->dequant_y2[0] = pc->Y2dequant[QIndex][0];
85   xd->dequant_uv[0] = pc->UVdequant[QIndex][0];
86 
87   for (i = 1; i < 16; ++i) {
88     xd->dequant_y1_dc[i] = xd->dequant_y1[i] = pc->Y1dequant[QIndex][1];
89     xd->dequant_y2[i] = pc->Y2dequant[QIndex][1];
90     xd->dequant_uv[i] = pc->UVdequant[QIndex][1];
91   }
92 }
93 
decode_macroblock(VP8D_COMP * pbi,MACROBLOCKD * xd,unsigned int mb_idx)94 static void decode_macroblock(VP8D_COMP *pbi, MACROBLOCKD *xd,
95                               unsigned int mb_idx) {
96   MB_PREDICTION_MODE mode;
97   int i;
98 #if CONFIG_ERROR_CONCEALMENT
99   int corruption_detected = 0;
100 #else
101   (void)mb_idx;
102 #endif
103 
104   if (xd->mode_info_context->mbmi.mb_skip_coeff) {
105     vp8_reset_mb_tokens_context(xd);
106   } else if (!vp8dx_bool_error(xd->current_bc)) {
107     int eobtotal;
108     eobtotal = vp8_decode_mb_tokens(pbi, xd);
109 
110     /* Special case:  Force the loopfilter to skip when eobtotal is zero */
111     xd->mode_info_context->mbmi.mb_skip_coeff = (eobtotal == 0);
112   }
113 
114   mode = xd->mode_info_context->mbmi.mode;
115 
116   if (xd->segmentation_enabled) vp8_mb_init_dequantizer(pbi, xd);
117 
118 #if CONFIG_ERROR_CONCEALMENT
119 
120   if (pbi->ec_active) {
121     int throw_residual;
122     /* When we have independent partitions we can apply residual even
123      * though other partitions within the frame are corrupt.
124      */
125     throw_residual =
126         (!pbi->independent_partitions && pbi->frame_corrupt_residual);
127     throw_residual = (throw_residual || vp8dx_bool_error(xd->current_bc));
128 
129     if ((mb_idx >= pbi->mvs_corrupt_from_mb || throw_residual)) {
130       /* MB with corrupt residuals or corrupt mode/motion vectors.
131        * Better to use the predictor as reconstruction.
132        */
133       pbi->frame_corrupt_residual = 1;
134       memset(xd->qcoeff, 0, sizeof(xd->qcoeff));
135 
136       corruption_detected = 1;
137 
138       /* force idct to be skipped for B_PRED and use the
139        * prediction only for reconstruction
140        * */
141       memset(xd->eobs, 0, 25);
142     }
143   }
144 #endif
145 
146   /* do prediction */
147   if (xd->mode_info_context->mbmi.ref_frame == INTRA_FRAME) {
148     vp8_build_intra_predictors_mbuv_s(
149         xd, xd->recon_above[1], xd->recon_above[2], xd->recon_left[1],
150         xd->recon_left[2], xd->recon_left_stride[1], xd->dst.u_buffer,
151         xd->dst.v_buffer, xd->dst.uv_stride);
152 
153     if (mode != B_PRED) {
154       vp8_build_intra_predictors_mby_s(
155           xd, xd->recon_above[0], xd->recon_left[0], xd->recon_left_stride[0],
156           xd->dst.y_buffer, xd->dst.y_stride);
157     } else {
158       short *DQC = xd->dequant_y1;
159       int dst_stride = xd->dst.y_stride;
160 
161       /* clear out residual eob info */
162       if (xd->mode_info_context->mbmi.mb_skip_coeff) memset(xd->eobs, 0, 25);
163 
164       intra_prediction_down_copy(xd, xd->recon_above[0] + 16);
165 
166       for (i = 0; i < 16; ++i) {
167         BLOCKD *b = &xd->block[i];
168         unsigned char *dst = xd->dst.y_buffer + b->offset;
169         B_PREDICTION_MODE b_mode = xd->mode_info_context->bmi[i].as_mode;
170         unsigned char *Above = dst - dst_stride;
171         unsigned char *yleft = dst - 1;
172         int left_stride = dst_stride;
173         unsigned char top_left = Above[-1];
174 
175         vp8_intra4x4_predict(Above, yleft, left_stride, b_mode, dst, dst_stride,
176                              top_left);
177 
178         if (xd->eobs[i]) {
179           if (xd->eobs[i] > 1) {
180             vp8_dequant_idct_add(b->qcoeff, DQC, dst, dst_stride);
181           } else {
182             vp8_dc_only_idct_add(b->qcoeff[0] * DQC[0], dst, dst_stride, dst,
183                                  dst_stride);
184             memset(b->qcoeff, 0, 2 * sizeof(b->qcoeff[0]));
185           }
186         }
187       }
188     }
189   } else {
190     vp8_build_inter_predictors_mb(xd);
191   }
192 
193 #if CONFIG_ERROR_CONCEALMENT
194   if (corruption_detected) {
195     return;
196   }
197 #endif
198 
199   if (!xd->mode_info_context->mbmi.mb_skip_coeff) {
200     /* dequantization and idct */
201     if (mode != B_PRED) {
202       short *DQC = xd->dequant_y1;
203 
204       if (mode != SPLITMV) {
205         BLOCKD *b = &xd->block[24];
206 
207         /* do 2nd order transform on the dc block */
208         if (xd->eobs[24] > 1) {
209           vp8_dequantize_b(b, xd->dequant_y2);
210 
211           vp8_short_inv_walsh4x4(&b->dqcoeff[0], xd->qcoeff);
212           memset(b->qcoeff, 0, 16 * sizeof(b->qcoeff[0]));
213         } else {
214           b->dqcoeff[0] = b->qcoeff[0] * xd->dequant_y2[0];
215           vp8_short_inv_walsh4x4_1(&b->dqcoeff[0], xd->qcoeff);
216           memset(b->qcoeff, 0, 2 * sizeof(b->qcoeff[0]));
217         }
218 
219         /* override the dc dequant constant in order to preserve the
220          * dc components
221          */
222         DQC = xd->dequant_y1_dc;
223       }
224 
225       vp8_dequant_idct_add_y_block(xd->qcoeff, DQC, xd->dst.y_buffer,
226                                    xd->dst.y_stride, xd->eobs);
227     }
228 
229     vp8_dequant_idct_add_uv_block(xd->qcoeff + 16 * 16, xd->dequant_uv,
230                                   xd->dst.u_buffer, xd->dst.v_buffer,
231                                   xd->dst.uv_stride, xd->eobs + 16);
232   }
233 }
234 
get_delta_q(vp8_reader * bc,int prev,int * q_update)235 static int get_delta_q(vp8_reader *bc, int prev, int *q_update) {
236   int ret_val = 0;
237 
238   if (vp8_read_bit(bc)) {
239     ret_val = vp8_read_literal(bc, 4);
240 
241     if (vp8_read_bit(bc)) ret_val = -ret_val;
242   }
243 
244   /* Trigger a quantizer update if the delta-q value has changed */
245   if (ret_val != prev) *q_update = 1;
246 
247   return ret_val;
248 }
249 
250 #ifdef PACKET_TESTING
251 #include <stdio.h>
252 FILE *vpxlog = 0;
253 #endif
254 
yv12_extend_frame_top_c(YV12_BUFFER_CONFIG * ybf)255 static void yv12_extend_frame_top_c(YV12_BUFFER_CONFIG *ybf) {
256   int i;
257   unsigned char *src_ptr1;
258   unsigned char *dest_ptr1;
259 
260   unsigned int Border;
261   int plane_stride;
262 
263   /***********/
264   /* Y Plane */
265   /***********/
266   Border = ybf->border;
267   plane_stride = ybf->y_stride;
268   src_ptr1 = ybf->y_buffer - Border;
269   dest_ptr1 = src_ptr1 - (Border * plane_stride);
270 
271   for (i = 0; i < (int)Border; ++i) {
272     memcpy(dest_ptr1, src_ptr1, plane_stride);
273     dest_ptr1 += plane_stride;
274   }
275 
276   /***********/
277   /* U Plane */
278   /***********/
279   plane_stride = ybf->uv_stride;
280   Border /= 2;
281   src_ptr1 = ybf->u_buffer - Border;
282   dest_ptr1 = src_ptr1 - (Border * plane_stride);
283 
284   for (i = 0; i < (int)(Border); ++i) {
285     memcpy(dest_ptr1, src_ptr1, plane_stride);
286     dest_ptr1 += plane_stride;
287   }
288 
289   /***********/
290   /* V Plane */
291   /***********/
292 
293   src_ptr1 = ybf->v_buffer - Border;
294   dest_ptr1 = src_ptr1 - (Border * plane_stride);
295 
296   for (i = 0; i < (int)(Border); ++i) {
297     memcpy(dest_ptr1, src_ptr1, plane_stride);
298     dest_ptr1 += plane_stride;
299   }
300 }
301 
yv12_extend_frame_bottom_c(YV12_BUFFER_CONFIG * ybf)302 static void yv12_extend_frame_bottom_c(YV12_BUFFER_CONFIG *ybf) {
303   int i;
304   unsigned char *src_ptr1, *src_ptr2;
305   unsigned char *dest_ptr2;
306 
307   unsigned int Border;
308   int plane_stride;
309   int plane_height;
310 
311   /***********/
312   /* Y Plane */
313   /***********/
314   Border = ybf->border;
315   plane_stride = ybf->y_stride;
316   plane_height = ybf->y_height;
317 
318   src_ptr1 = ybf->y_buffer - Border;
319   src_ptr2 = src_ptr1 + (plane_height * plane_stride) - plane_stride;
320   dest_ptr2 = src_ptr2 + plane_stride;
321 
322   for (i = 0; i < (int)Border; ++i) {
323     memcpy(dest_ptr2, src_ptr2, plane_stride);
324     dest_ptr2 += plane_stride;
325   }
326 
327   /***********/
328   /* U Plane */
329   /***********/
330   plane_stride = ybf->uv_stride;
331   plane_height = ybf->uv_height;
332   Border /= 2;
333 
334   src_ptr1 = ybf->u_buffer - Border;
335   src_ptr2 = src_ptr1 + (plane_height * plane_stride) - plane_stride;
336   dest_ptr2 = src_ptr2 + plane_stride;
337 
338   for (i = 0; i < (int)(Border); ++i) {
339     memcpy(dest_ptr2, src_ptr2, plane_stride);
340     dest_ptr2 += plane_stride;
341   }
342 
343   /***********/
344   /* V Plane */
345   /***********/
346 
347   src_ptr1 = ybf->v_buffer - Border;
348   src_ptr2 = src_ptr1 + (plane_height * plane_stride) - plane_stride;
349   dest_ptr2 = src_ptr2 + plane_stride;
350 
351   for (i = 0; i < (int)(Border); ++i) {
352     memcpy(dest_ptr2, src_ptr2, plane_stride);
353     dest_ptr2 += plane_stride;
354   }
355 }
356 
yv12_extend_frame_left_right_c(YV12_BUFFER_CONFIG * ybf,unsigned char * y_src,unsigned char * u_src,unsigned char * v_src)357 static void yv12_extend_frame_left_right_c(YV12_BUFFER_CONFIG *ybf,
358                                            unsigned char *y_src,
359                                            unsigned char *u_src,
360                                            unsigned char *v_src) {
361   int i;
362   unsigned char *src_ptr1, *src_ptr2;
363   unsigned char *dest_ptr1, *dest_ptr2;
364 
365   unsigned int Border;
366   int plane_stride;
367   int plane_height;
368   int plane_width;
369 
370   /***********/
371   /* Y Plane */
372   /***********/
373   Border = ybf->border;
374   plane_stride = ybf->y_stride;
375   plane_height = 16;
376   plane_width = ybf->y_width;
377 
378   /* copy the left and right most columns out */
379   src_ptr1 = y_src;
380   src_ptr2 = src_ptr1 + plane_width - 1;
381   dest_ptr1 = src_ptr1 - Border;
382   dest_ptr2 = src_ptr2 + 1;
383 
384   for (i = 0; i < plane_height; ++i) {
385     memset(dest_ptr1, src_ptr1[0], Border);
386     memset(dest_ptr2, src_ptr2[0], Border);
387     src_ptr1 += plane_stride;
388     src_ptr2 += plane_stride;
389     dest_ptr1 += plane_stride;
390     dest_ptr2 += plane_stride;
391   }
392 
393   /***********/
394   /* U Plane */
395   /***********/
396   plane_stride = ybf->uv_stride;
397   plane_height = 8;
398   plane_width = ybf->uv_width;
399   Border /= 2;
400 
401   /* copy the left and right most columns out */
402   src_ptr1 = u_src;
403   src_ptr2 = src_ptr1 + plane_width - 1;
404   dest_ptr1 = src_ptr1 - Border;
405   dest_ptr2 = src_ptr2 + 1;
406 
407   for (i = 0; i < plane_height; ++i) {
408     memset(dest_ptr1, src_ptr1[0], Border);
409     memset(dest_ptr2, src_ptr2[0], Border);
410     src_ptr1 += plane_stride;
411     src_ptr2 += plane_stride;
412     dest_ptr1 += plane_stride;
413     dest_ptr2 += plane_stride;
414   }
415 
416   /***********/
417   /* V Plane */
418   /***********/
419 
420   /* copy the left and right most columns out */
421   src_ptr1 = v_src;
422   src_ptr2 = src_ptr1 + plane_width - 1;
423   dest_ptr1 = src_ptr1 - Border;
424   dest_ptr2 = src_ptr2 + 1;
425 
426   for (i = 0; i < plane_height; ++i) {
427     memset(dest_ptr1, src_ptr1[0], Border);
428     memset(dest_ptr2, src_ptr2[0], Border);
429     src_ptr1 += plane_stride;
430     src_ptr2 += plane_stride;
431     dest_ptr1 += plane_stride;
432     dest_ptr2 += plane_stride;
433   }
434 }
435 
decode_mb_rows(VP8D_COMP * pbi)436 static void decode_mb_rows(VP8D_COMP *pbi) {
437   VP8_COMMON *const pc = &pbi->common;
438   MACROBLOCKD *const xd = &pbi->mb;
439 
440   MODE_INFO *lf_mic = xd->mode_info_context;
441 
442   int ibc = 0;
443   int num_part = 1 << pc->multi_token_partition;
444 
445   int recon_yoffset, recon_uvoffset;
446   int mb_row, mb_col;
447   int mb_idx = 0;
448 
449   YV12_BUFFER_CONFIG *yv12_fb_new = pbi->dec_fb_ref[INTRA_FRAME];
450 
451   int recon_y_stride = yv12_fb_new->y_stride;
452   int recon_uv_stride = yv12_fb_new->uv_stride;
453 
454   unsigned char *ref_buffer[MAX_REF_FRAMES][3];
455   unsigned char *dst_buffer[3];
456   unsigned char *lf_dst[3];
457   unsigned char *eb_dst[3];
458   int i;
459   int ref_fb_corrupted[MAX_REF_FRAMES];
460 
461   ref_fb_corrupted[INTRA_FRAME] = 0;
462 
463   for (i = 1; i < MAX_REF_FRAMES; ++i) {
464     YV12_BUFFER_CONFIG *this_fb = pbi->dec_fb_ref[i];
465 
466     ref_buffer[i][0] = this_fb->y_buffer;
467     ref_buffer[i][1] = this_fb->u_buffer;
468     ref_buffer[i][2] = this_fb->v_buffer;
469 
470     ref_fb_corrupted[i] = this_fb->corrupted;
471   }
472 
473   /* Set up the buffer pointers */
474   eb_dst[0] = lf_dst[0] = dst_buffer[0] = yv12_fb_new->y_buffer;
475   eb_dst[1] = lf_dst[1] = dst_buffer[1] = yv12_fb_new->u_buffer;
476   eb_dst[2] = lf_dst[2] = dst_buffer[2] = yv12_fb_new->v_buffer;
477 
478   xd->up_available = 0;
479 
480   /* Initialize the loop filter for this frame. */
481   if (pc->filter_level) vp8_loop_filter_frame_init(pc, xd, pc->filter_level);
482 
483   vp8_setup_intra_recon_top_line(yv12_fb_new);
484 
485   /* Decode the individual macro block */
486   for (mb_row = 0; mb_row < pc->mb_rows; ++mb_row) {
487     if (num_part > 1) {
488       xd->current_bc = &pbi->mbc[ibc];
489       ibc++;
490 
491       if (ibc == num_part) ibc = 0;
492     }
493 
494     recon_yoffset = mb_row * recon_y_stride * 16;
495     recon_uvoffset = mb_row * recon_uv_stride * 8;
496 
497     /* reset contexts */
498     xd->above_context = pc->above_context;
499     memset(xd->left_context, 0, sizeof(ENTROPY_CONTEXT_PLANES));
500 
501     xd->left_available = 0;
502 
503     xd->mb_to_top_edge = -((mb_row * 16) << 3);
504     xd->mb_to_bottom_edge = ((pc->mb_rows - 1 - mb_row) * 16) << 3;
505 
506     xd->recon_above[0] = dst_buffer[0] + recon_yoffset;
507     xd->recon_above[1] = dst_buffer[1] + recon_uvoffset;
508     xd->recon_above[2] = dst_buffer[2] + recon_uvoffset;
509 
510     xd->recon_left[0] = xd->recon_above[0] - 1;
511     xd->recon_left[1] = xd->recon_above[1] - 1;
512     xd->recon_left[2] = xd->recon_above[2] - 1;
513 
514     xd->recon_above[0] -= xd->dst.y_stride;
515     xd->recon_above[1] -= xd->dst.uv_stride;
516     xd->recon_above[2] -= xd->dst.uv_stride;
517 
518     /* TODO: move to outside row loop */
519     xd->recon_left_stride[0] = xd->dst.y_stride;
520     xd->recon_left_stride[1] = xd->dst.uv_stride;
521 
522     setup_intra_recon_left(xd->recon_left[0], xd->recon_left[1],
523                            xd->recon_left[2], xd->dst.y_stride,
524                            xd->dst.uv_stride);
525 
526     for (mb_col = 0; mb_col < pc->mb_cols; ++mb_col) {
527       /* Distance of Mb to the various image edges.
528        * These are specified to 8th pel as they are always compared to values
529        * that are in 1/8th pel units
530        */
531       xd->mb_to_left_edge = -((mb_col * 16) << 3);
532       xd->mb_to_right_edge = ((pc->mb_cols - 1 - mb_col) * 16) << 3;
533 
534 #if CONFIG_ERROR_CONCEALMENT
535       {
536         int corrupt_residual =
537             (!pbi->independent_partitions && pbi->frame_corrupt_residual) ||
538             vp8dx_bool_error(xd->current_bc);
539         if (pbi->ec_active &&
540             xd->mode_info_context->mbmi.ref_frame == INTRA_FRAME &&
541             corrupt_residual) {
542           /* We have an intra block with corrupt coefficients, better to
543            * conceal with an inter block. Interpolate MVs from neighboring
544            * MBs.
545            *
546            * Note that for the first mb with corrupt residual in a frame,
547            * we might not discover that before decoding the residual. That
548            * happens after this check, and therefore no inter concealment
549            * will be done.
550            */
551           vp8_interpolate_motion(xd, mb_row, mb_col, pc->mb_rows, pc->mb_cols);
552         }
553       }
554 #endif
555 
556       xd->dst.y_buffer = dst_buffer[0] + recon_yoffset;
557       xd->dst.u_buffer = dst_buffer[1] + recon_uvoffset;
558       xd->dst.v_buffer = dst_buffer[2] + recon_uvoffset;
559 
560       if (xd->mode_info_context->mbmi.ref_frame >= LAST_FRAME) {
561         const MV_REFERENCE_FRAME ref = xd->mode_info_context->mbmi.ref_frame;
562         xd->pre.y_buffer = ref_buffer[ref][0] + recon_yoffset;
563         xd->pre.u_buffer = ref_buffer[ref][1] + recon_uvoffset;
564         xd->pre.v_buffer = ref_buffer[ref][2] + recon_uvoffset;
565       } else {
566         // ref_frame is INTRA_FRAME, pre buffer should not be used.
567         xd->pre.y_buffer = 0;
568         xd->pre.u_buffer = 0;
569         xd->pre.v_buffer = 0;
570       }
571 
572       /* propagate errors from reference frames */
573       xd->corrupted |= ref_fb_corrupted[xd->mode_info_context->mbmi.ref_frame];
574 
575       decode_macroblock(pbi, xd, mb_idx);
576 
577       mb_idx++;
578       xd->left_available = 1;
579 
580       /* check if the boolean decoder has suffered an error */
581       xd->corrupted |= vp8dx_bool_error(xd->current_bc);
582 
583       xd->recon_above[0] += 16;
584       xd->recon_above[1] += 8;
585       xd->recon_above[2] += 8;
586       xd->recon_left[0] += 16;
587       xd->recon_left[1] += 8;
588       xd->recon_left[2] += 8;
589 
590       recon_yoffset += 16;
591       recon_uvoffset += 8;
592 
593       ++xd->mode_info_context; /* next mb */
594 
595       xd->above_context++;
596     }
597 
598     /* adjust to the next row of mbs */
599     vp8_extend_mb_row(yv12_fb_new, xd->dst.y_buffer + 16, xd->dst.u_buffer + 8,
600                       xd->dst.v_buffer + 8);
601 
602     ++xd->mode_info_context; /* skip prediction column */
603     xd->up_available = 1;
604 
605     if (pc->filter_level) {
606       if (mb_row > 0) {
607         if (pc->filter_type == NORMAL_LOOPFILTER) {
608           vp8_loop_filter_row_normal(pc, lf_mic, mb_row - 1, recon_y_stride,
609                                      recon_uv_stride, lf_dst[0], lf_dst[1],
610                                      lf_dst[2]);
611         } else {
612           vp8_loop_filter_row_simple(pc, lf_mic, mb_row - 1, recon_y_stride,
613                                      recon_uv_stride, lf_dst[0], lf_dst[1],
614                                      lf_dst[2]);
615         }
616         if (mb_row > 1) {
617           yv12_extend_frame_left_right_c(yv12_fb_new, eb_dst[0], eb_dst[1],
618                                          eb_dst[2]);
619 
620           eb_dst[0] += recon_y_stride * 16;
621           eb_dst[1] += recon_uv_stride * 8;
622           eb_dst[2] += recon_uv_stride * 8;
623         }
624 
625         lf_dst[0] += recon_y_stride * 16;
626         lf_dst[1] += recon_uv_stride * 8;
627         lf_dst[2] += recon_uv_stride * 8;
628         lf_mic += pc->mb_cols;
629         lf_mic++; /* Skip border mb */
630       }
631     } else {
632       if (mb_row > 0) {
633         /**/
634         yv12_extend_frame_left_right_c(yv12_fb_new, eb_dst[0], eb_dst[1],
635                                        eb_dst[2]);
636         eb_dst[0] += recon_y_stride * 16;
637         eb_dst[1] += recon_uv_stride * 8;
638         eb_dst[2] += recon_uv_stride * 8;
639       }
640     }
641   }
642 
643   if (pc->filter_level) {
644     if (pc->filter_type == NORMAL_LOOPFILTER) {
645       vp8_loop_filter_row_normal(pc, lf_mic, mb_row - 1, recon_y_stride,
646                                  recon_uv_stride, lf_dst[0], lf_dst[1],
647                                  lf_dst[2]);
648     } else {
649       vp8_loop_filter_row_simple(pc, lf_mic, mb_row - 1, recon_y_stride,
650                                  recon_uv_stride, lf_dst[0], lf_dst[1],
651                                  lf_dst[2]);
652     }
653 
654     yv12_extend_frame_left_right_c(yv12_fb_new, eb_dst[0], eb_dst[1],
655                                    eb_dst[2]);
656     eb_dst[0] += recon_y_stride * 16;
657     eb_dst[1] += recon_uv_stride * 8;
658     eb_dst[2] += recon_uv_stride * 8;
659   }
660   yv12_extend_frame_left_right_c(yv12_fb_new, eb_dst[0], eb_dst[1], eb_dst[2]);
661   yv12_extend_frame_top_c(yv12_fb_new);
662   yv12_extend_frame_bottom_c(yv12_fb_new);
663 }
664 
read_partition_size(VP8D_COMP * pbi,const unsigned char * cx_size)665 static unsigned int read_partition_size(VP8D_COMP *pbi,
666                                         const unsigned char *cx_size) {
667   unsigned char temp[3];
668   if (pbi->decrypt_cb) {
669     pbi->decrypt_cb(pbi->decrypt_state, cx_size, temp, 3);
670     cx_size = temp;
671   }
672   return cx_size[0] + (cx_size[1] << 8) + (cx_size[2] << 16);
673 }
674 
read_is_valid(const unsigned char * start,size_t len,const unsigned char * end)675 static int read_is_valid(const unsigned char *start, size_t len,
676                          const unsigned char *end) {
677   return (start + len > start && start + len <= end);
678 }
679 
read_available_partition_size(VP8D_COMP * pbi,const unsigned char * token_part_sizes,const unsigned char * fragment_start,const unsigned char * first_fragment_end,const unsigned char * fragment_end,int i,int num_part)680 static unsigned int read_available_partition_size(
681     VP8D_COMP *pbi, const unsigned char *token_part_sizes,
682     const unsigned char *fragment_start,
683     const unsigned char *first_fragment_end, const unsigned char *fragment_end,
684     int i, int num_part) {
685   VP8_COMMON *pc = &pbi->common;
686   const unsigned char *partition_size_ptr = token_part_sizes + i * 3;
687   unsigned int partition_size = 0;
688   ptrdiff_t bytes_left = fragment_end - fragment_start;
689   /* Calculate the length of this partition. The last partition
690    * size is implicit. If the partition size can't be read, then
691    * either use the remaining data in the buffer (for EC mode)
692    * or throw an error.
693    */
694   if (i < num_part - 1) {
695     if (read_is_valid(partition_size_ptr, 3, first_fragment_end)) {
696       partition_size = read_partition_size(pbi, partition_size_ptr);
697     } else if (pbi->ec_active) {
698       partition_size = (unsigned int)bytes_left;
699     } else {
700       vpx_internal_error(&pc->error, VPX_CODEC_CORRUPT_FRAME,
701                          "Truncated partition size data");
702     }
703   } else {
704     partition_size = (unsigned int)bytes_left;
705   }
706 
707   /* Validate the calculated partition length. If the buffer
708    * described by the partition can't be fully read, then restrict
709    * it to the portion that can be (for EC mode) or throw an error.
710    */
711   if (!read_is_valid(fragment_start, partition_size, fragment_end)) {
712     if (pbi->ec_active) {
713       partition_size = (unsigned int)bytes_left;
714     } else {
715       vpx_internal_error(&pc->error, VPX_CODEC_CORRUPT_FRAME,
716                          "Truncated packet or corrupt partition "
717                          "%d length",
718                          i + 1);
719     }
720   }
721   return partition_size;
722 }
723 
setup_token_decoder(VP8D_COMP * pbi,const unsigned char * token_part_sizes)724 static void setup_token_decoder(VP8D_COMP *pbi,
725                                 const unsigned char *token_part_sizes) {
726   vp8_reader *bool_decoder = &pbi->mbc[0];
727   unsigned int partition_idx;
728   unsigned int fragment_idx;
729   unsigned int num_token_partitions;
730   const unsigned char *first_fragment_end =
731       pbi->fragments.ptrs[0] + pbi->fragments.sizes[0];
732 
733   TOKEN_PARTITION multi_token_partition =
734       (TOKEN_PARTITION)vp8_read_literal(&pbi->mbc[8], 2);
735   if (!vp8dx_bool_error(&pbi->mbc[8])) {
736     pbi->common.multi_token_partition = multi_token_partition;
737   }
738   num_token_partitions = 1 << pbi->common.multi_token_partition;
739 
740   /* Check for partitions within the fragments and unpack the fragments
741    * so that each fragment pointer points to its corresponding partition. */
742   for (fragment_idx = 0; fragment_idx < pbi->fragments.count; ++fragment_idx) {
743     unsigned int fragment_size = pbi->fragments.sizes[fragment_idx];
744     const unsigned char *fragment_end =
745         pbi->fragments.ptrs[fragment_idx] + fragment_size;
746     /* Special case for handling the first partition since we have already
747      * read its size. */
748     if (fragment_idx == 0) {
749       /* Size of first partition + token partition sizes element */
750       ptrdiff_t ext_first_part_size = token_part_sizes -
751                                       pbi->fragments.ptrs[0] +
752                                       3 * (num_token_partitions - 1);
753       fragment_size -= (unsigned int)ext_first_part_size;
754       if (fragment_size > 0) {
755         pbi->fragments.sizes[0] = (unsigned int)ext_first_part_size;
756         /* The fragment contains an additional partition. Move to
757          * next. */
758         fragment_idx++;
759         pbi->fragments.ptrs[fragment_idx] =
760             pbi->fragments.ptrs[0] + pbi->fragments.sizes[0];
761       }
762     }
763     /* Split the chunk into partitions read from the bitstream */
764     while (fragment_size > 0) {
765       ptrdiff_t partition_size = read_available_partition_size(
766           pbi, token_part_sizes, pbi->fragments.ptrs[fragment_idx],
767           first_fragment_end, fragment_end, fragment_idx - 1,
768           num_token_partitions);
769       pbi->fragments.sizes[fragment_idx] = (unsigned int)partition_size;
770       fragment_size -= (unsigned int)partition_size;
771       assert(fragment_idx <= num_token_partitions);
772       if (fragment_size > 0) {
773         /* The fragment contains an additional partition.
774          * Move to next. */
775         fragment_idx++;
776         pbi->fragments.ptrs[fragment_idx] =
777             pbi->fragments.ptrs[fragment_idx - 1] + partition_size;
778       }
779     }
780   }
781 
782   pbi->fragments.count = num_token_partitions + 1;
783 
784   for (partition_idx = 1; partition_idx < pbi->fragments.count;
785        ++partition_idx) {
786     if (vp8dx_start_decode(bool_decoder, pbi->fragments.ptrs[partition_idx],
787                            pbi->fragments.sizes[partition_idx], pbi->decrypt_cb,
788                            pbi->decrypt_state)) {
789       vpx_internal_error(&pbi->common.error, VPX_CODEC_MEM_ERROR,
790                          "Failed to allocate bool decoder %d", partition_idx);
791     }
792 
793     bool_decoder++;
794   }
795 
796 #if CONFIG_MULTITHREAD
797   /* Clamp number of decoder threads */
798   if (pbi->decoding_thread_count > num_token_partitions - 1) {
799     pbi->decoding_thread_count = num_token_partitions - 1;
800   }
801   if ((int)pbi->decoding_thread_count > pbi->common.mb_rows - 1) {
802     assert(pbi->common.mb_rows > 0);
803     pbi->decoding_thread_count = pbi->common.mb_rows - 1;
804   }
805 #endif
806 }
807 
init_frame(VP8D_COMP * pbi)808 static void init_frame(VP8D_COMP *pbi) {
809   VP8_COMMON *const pc = &pbi->common;
810   MACROBLOCKD *const xd = &pbi->mb;
811 
812   if (pc->frame_type == KEY_FRAME) {
813     /* Various keyframe initializations */
814     memcpy(pc->fc.mvc, vp8_default_mv_context, sizeof(vp8_default_mv_context));
815 
816     vp8_init_mbmode_probs(pc);
817 
818     vp8_default_coef_probs(pc);
819 
820     /* reset the segment feature data to 0 with delta coding (Default state). */
821     memset(xd->segment_feature_data, 0, sizeof(xd->segment_feature_data));
822     xd->mb_segement_abs_delta = SEGMENT_DELTADATA;
823 
824     /* reset the mode ref deltasa for loop filter */
825     memset(xd->ref_lf_deltas, 0, sizeof(xd->ref_lf_deltas));
826     memset(xd->mode_lf_deltas, 0, sizeof(xd->mode_lf_deltas));
827 
828     /* All buffers are implicitly updated on key frames. */
829     pc->refresh_golden_frame = 1;
830     pc->refresh_alt_ref_frame = 1;
831     pc->copy_buffer_to_gf = 0;
832     pc->copy_buffer_to_arf = 0;
833 
834     /* Note that Golden and Altref modes cannot be used on a key frame so
835      * ref_frame_sign_bias[] is undefined and meaningless
836      */
837     pc->ref_frame_sign_bias[GOLDEN_FRAME] = 0;
838     pc->ref_frame_sign_bias[ALTREF_FRAME] = 0;
839   } else {
840     /* To enable choice of different interploation filters */
841     if (!pc->use_bilinear_mc_filter) {
842       xd->subpixel_predict = vp8_sixtap_predict4x4;
843       xd->subpixel_predict8x4 = vp8_sixtap_predict8x4;
844       xd->subpixel_predict8x8 = vp8_sixtap_predict8x8;
845       xd->subpixel_predict16x16 = vp8_sixtap_predict16x16;
846     } else {
847       xd->subpixel_predict = vp8_bilinear_predict4x4;
848       xd->subpixel_predict8x4 = vp8_bilinear_predict8x4;
849       xd->subpixel_predict8x8 = vp8_bilinear_predict8x8;
850       xd->subpixel_predict16x16 = vp8_bilinear_predict16x16;
851     }
852 
853     if (pbi->decoded_key_frame && pbi->ec_enabled && !pbi->ec_active) {
854       pbi->ec_active = 1;
855     }
856   }
857 
858   xd->left_context = &pc->left_context;
859   xd->mode_info_context = pc->mi;
860   xd->frame_type = pc->frame_type;
861   xd->mode_info_context->mbmi.mode = DC_PRED;
862   xd->mode_info_stride = pc->mode_info_stride;
863   xd->corrupted = 0; /* init without corruption */
864 
865   xd->fullpixel_mask = 0xffffffff;
866   if (pc->full_pixel) xd->fullpixel_mask = 0xfffffff8;
867 }
868 
vp8_decode_frame(VP8D_COMP * pbi)869 int vp8_decode_frame(VP8D_COMP *pbi) {
870   vp8_reader *const bc = &pbi->mbc[8];
871   VP8_COMMON *const pc = &pbi->common;
872   MACROBLOCKD *const xd = &pbi->mb;
873   const unsigned char *data = pbi->fragments.ptrs[0];
874   const unsigned int data_sz = pbi->fragments.sizes[0];
875   const unsigned char *data_end = data + data_sz;
876   ptrdiff_t first_partition_length_in_bytes;
877 
878   int i, j, k, l;
879   const int *const mb_feature_data_bits = vp8_mb_feature_data_bits;
880   int corrupt_tokens = 0;
881   int prev_independent_partitions = pbi->independent_partitions;
882 
883   YV12_BUFFER_CONFIG *yv12_fb_new = pbi->dec_fb_ref[INTRA_FRAME];
884 
885   /* start with no corruption of current frame */
886   xd->corrupted = 0;
887   yv12_fb_new->corrupted = 0;
888 
889   if (data_end - data < 3) {
890     if (!pbi->ec_active) {
891       vpx_internal_error(&pc->error, VPX_CODEC_CORRUPT_FRAME,
892                          "Truncated packet");
893     }
894 
895     /* Declare the missing frame as an inter frame since it will
896        be handled as an inter frame when we have estimated its
897        motion vectors. */
898     pc->frame_type = INTER_FRAME;
899     pc->version = 0;
900     pc->show_frame = 1;
901     first_partition_length_in_bytes = 0;
902   } else {
903     unsigned char clear_buffer[10];
904     const unsigned char *clear = data;
905     if (pbi->decrypt_cb) {
906       int n = (int)VPXMIN(sizeof(clear_buffer), data_sz);
907       pbi->decrypt_cb(pbi->decrypt_state, data, clear_buffer, n);
908       clear = clear_buffer;
909     }
910 
911     pc->frame_type = (FRAME_TYPE)(clear[0] & 1);
912     pc->version = (clear[0] >> 1) & 7;
913     pc->show_frame = (clear[0] >> 4) & 1;
914     first_partition_length_in_bytes =
915         (clear[0] | (clear[1] << 8) | (clear[2] << 16)) >> 5;
916 
917     if (!pbi->ec_active && (data + first_partition_length_in_bytes > data_end ||
918                             data + first_partition_length_in_bytes < data)) {
919       vpx_internal_error(&pc->error, VPX_CODEC_CORRUPT_FRAME,
920                          "Truncated packet or corrupt partition 0 length");
921     }
922 
923     data += 3;
924     clear += 3;
925 
926     vp8_setup_version(pc);
927 
928     if (pc->frame_type == KEY_FRAME) {
929       /* vet via sync code */
930       /* When error concealment is enabled we should only check the sync
931        * code if we have enough bits available
932        */
933       if (data + 3 < data_end) {
934         if (clear[0] != 0x9d || clear[1] != 0x01 || clear[2] != 0x2a) {
935           vpx_internal_error(&pc->error, VPX_CODEC_UNSUP_BITSTREAM,
936                              "Invalid frame sync code");
937         }
938       }
939 
940       /* If error concealment is enabled we should only parse the new size
941        * if we have enough data. Otherwise we will end up with the wrong
942        * size.
943        */
944       if (data + 6 < data_end) {
945         pc->Width = (clear[3] | (clear[4] << 8)) & 0x3fff;
946         pc->horiz_scale = clear[4] >> 6;
947         pc->Height = (clear[5] | (clear[6] << 8)) & 0x3fff;
948         pc->vert_scale = clear[6] >> 6;
949         data += 7;
950       } else if (!pbi->ec_active) {
951         vpx_internal_error(&pc->error, VPX_CODEC_CORRUPT_FRAME,
952                            "Truncated key frame header");
953       } else {
954         /* Error concealment is active, clear the frame. */
955         data = data_end;
956       }
957     } else {
958       memcpy(&xd->pre, yv12_fb_new, sizeof(YV12_BUFFER_CONFIG));
959       memcpy(&xd->dst, yv12_fb_new, sizeof(YV12_BUFFER_CONFIG));
960     }
961   }
962   if ((!pbi->decoded_key_frame && pc->frame_type != KEY_FRAME)) {
963     return -1;
964   }
965 
966   init_frame(pbi);
967 
968   if (vp8dx_start_decode(bc, data, (unsigned int)(data_end - data),
969                          pbi->decrypt_cb, pbi->decrypt_state)) {
970     vpx_internal_error(&pc->error, VPX_CODEC_MEM_ERROR,
971                        "Failed to allocate bool decoder 0");
972   }
973   if (pc->frame_type == KEY_FRAME) {
974     (void)vp8_read_bit(bc);  // colorspace
975     pc->clamp_type = (CLAMP_TYPE)vp8_read_bit(bc);
976   }
977 
978   /* Is segmentation enabled */
979   xd->segmentation_enabled = (unsigned char)vp8_read_bit(bc);
980 
981   if (xd->segmentation_enabled) {
982     /* Signal whether or not the segmentation map is being explicitly updated
983      * this frame. */
984     xd->update_mb_segmentation_map = (unsigned char)vp8_read_bit(bc);
985     xd->update_mb_segmentation_data = (unsigned char)vp8_read_bit(bc);
986 
987     if (xd->update_mb_segmentation_data) {
988       xd->mb_segement_abs_delta = (unsigned char)vp8_read_bit(bc);
989 
990       memset(xd->segment_feature_data, 0, sizeof(xd->segment_feature_data));
991 
992       /* For each segmentation feature (Quant and loop filter level) */
993       for (i = 0; i < MB_LVL_MAX; ++i) {
994         for (j = 0; j < MAX_MB_SEGMENTS; ++j) {
995           /* Frame level data */
996           if (vp8_read_bit(bc)) {
997             xd->segment_feature_data[i][j] =
998                 (signed char)vp8_read_literal(bc, mb_feature_data_bits[i]);
999 
1000             if (vp8_read_bit(bc)) {
1001               xd->segment_feature_data[i][j] = -xd->segment_feature_data[i][j];
1002             }
1003           } else {
1004             xd->segment_feature_data[i][j] = 0;
1005           }
1006         }
1007       }
1008     }
1009 
1010     if (xd->update_mb_segmentation_map) {
1011       /* Which macro block level features are enabled */
1012       memset(xd->mb_segment_tree_probs, 255, sizeof(xd->mb_segment_tree_probs));
1013 
1014       /* Read the probs used to decode the segment id for each macro block. */
1015       for (i = 0; i < MB_FEATURE_TREE_PROBS; ++i) {
1016         /* If not explicitly set value is defaulted to 255 by memset above */
1017         if (vp8_read_bit(bc)) {
1018           xd->mb_segment_tree_probs[i] = (vp8_prob)vp8_read_literal(bc, 8);
1019         }
1020       }
1021     }
1022   } else {
1023     /* No segmentation updates on this frame */
1024     xd->update_mb_segmentation_map = 0;
1025     xd->update_mb_segmentation_data = 0;
1026   }
1027 
1028   /* Read the loop filter level and type */
1029   pc->filter_type = (LOOPFILTERTYPE)vp8_read_bit(bc);
1030   pc->filter_level = vp8_read_literal(bc, 6);
1031   pc->sharpness_level = vp8_read_literal(bc, 3);
1032 
1033   /* Read in loop filter deltas applied at the MB level based on mode or ref
1034    * frame. */
1035   xd->mode_ref_lf_delta_update = 0;
1036   xd->mode_ref_lf_delta_enabled = (unsigned char)vp8_read_bit(bc);
1037 
1038   if (xd->mode_ref_lf_delta_enabled) {
1039     /* Do the deltas need to be updated */
1040     xd->mode_ref_lf_delta_update = (unsigned char)vp8_read_bit(bc);
1041 
1042     if (xd->mode_ref_lf_delta_update) {
1043       /* Send update */
1044       for (i = 0; i < MAX_REF_LF_DELTAS; ++i) {
1045         if (vp8_read_bit(bc)) {
1046           /*sign = vp8_read_bit( bc );*/
1047           xd->ref_lf_deltas[i] = (signed char)vp8_read_literal(bc, 6);
1048 
1049           if (vp8_read_bit(bc)) { /* Apply sign */
1050             xd->ref_lf_deltas[i] = xd->ref_lf_deltas[i] * -1;
1051           }
1052         }
1053       }
1054 
1055       /* Send update */
1056       for (i = 0; i < MAX_MODE_LF_DELTAS; ++i) {
1057         if (vp8_read_bit(bc)) {
1058           /*sign = vp8_read_bit( bc );*/
1059           xd->mode_lf_deltas[i] = (signed char)vp8_read_literal(bc, 6);
1060 
1061           if (vp8_read_bit(bc)) { /* Apply sign */
1062             xd->mode_lf_deltas[i] = xd->mode_lf_deltas[i] * -1;
1063           }
1064         }
1065       }
1066     }
1067   }
1068 
1069   setup_token_decoder(pbi, data + first_partition_length_in_bytes);
1070 
1071   xd->current_bc = &pbi->mbc[0];
1072 
1073   /* Read the default quantizers. */
1074   {
1075     int Q, q_update;
1076 
1077     Q = vp8_read_literal(bc, 7); /* AC 1st order Q = default */
1078     pc->base_qindex = Q;
1079     q_update = 0;
1080     pc->y1dc_delta_q = get_delta_q(bc, pc->y1dc_delta_q, &q_update);
1081     pc->y2dc_delta_q = get_delta_q(bc, pc->y2dc_delta_q, &q_update);
1082     pc->y2ac_delta_q = get_delta_q(bc, pc->y2ac_delta_q, &q_update);
1083     pc->uvdc_delta_q = get_delta_q(bc, pc->uvdc_delta_q, &q_update);
1084     pc->uvac_delta_q = get_delta_q(bc, pc->uvac_delta_q, &q_update);
1085 
1086     if (q_update) vp8cx_init_de_quantizer(pbi);
1087 
1088     /* MB level dequantizer setup */
1089     vp8_mb_init_dequantizer(pbi, &pbi->mb);
1090   }
1091 
1092   /* Determine if the golden frame or ARF buffer should be updated and how.
1093    * For all non key frames the GF and ARF refresh flags and sign bias
1094    * flags must be set explicitly.
1095    */
1096   if (pc->frame_type != KEY_FRAME) {
1097     /* Should the GF or ARF be updated from the current frame */
1098     pc->refresh_golden_frame = vp8_read_bit(bc);
1099 #if CONFIG_ERROR_CONCEALMENT
1100     /* Assume we shouldn't refresh golden if the bit is missing */
1101     xd->corrupted |= vp8dx_bool_error(bc);
1102     if (pbi->ec_active && xd->corrupted) pc->refresh_golden_frame = 0;
1103 #endif
1104 
1105     pc->refresh_alt_ref_frame = vp8_read_bit(bc);
1106 #if CONFIG_ERROR_CONCEALMENT
1107     /* Assume we shouldn't refresh altref if the bit is missing */
1108     xd->corrupted |= vp8dx_bool_error(bc);
1109     if (pbi->ec_active && xd->corrupted) pc->refresh_alt_ref_frame = 0;
1110 #endif
1111 
1112     /* Buffer to buffer copy flags. */
1113     pc->copy_buffer_to_gf = 0;
1114 
1115     if (!pc->refresh_golden_frame) {
1116       pc->copy_buffer_to_gf = vp8_read_literal(bc, 2);
1117     }
1118 
1119 #if CONFIG_ERROR_CONCEALMENT
1120     /* Assume we shouldn't copy to the golden if the bit is missing */
1121     xd->corrupted |= vp8dx_bool_error(bc);
1122     if (pbi->ec_active && xd->corrupted) pc->copy_buffer_to_gf = 0;
1123 #endif
1124 
1125     pc->copy_buffer_to_arf = 0;
1126 
1127     if (!pc->refresh_alt_ref_frame) {
1128       pc->copy_buffer_to_arf = vp8_read_literal(bc, 2);
1129     }
1130 
1131 #if CONFIG_ERROR_CONCEALMENT
1132     /* Assume we shouldn't copy to the alt-ref if the bit is missing */
1133     xd->corrupted |= vp8dx_bool_error(bc);
1134     if (pbi->ec_active && xd->corrupted) pc->copy_buffer_to_arf = 0;
1135 #endif
1136 
1137     pc->ref_frame_sign_bias[GOLDEN_FRAME] = vp8_read_bit(bc);
1138     pc->ref_frame_sign_bias[ALTREF_FRAME] = vp8_read_bit(bc);
1139   }
1140 
1141   pc->refresh_entropy_probs = vp8_read_bit(bc);
1142 #if CONFIG_ERROR_CONCEALMENT
1143   /* Assume we shouldn't refresh the probabilities if the bit is
1144    * missing */
1145   xd->corrupted |= vp8dx_bool_error(bc);
1146   if (pbi->ec_active && xd->corrupted) pc->refresh_entropy_probs = 0;
1147 #endif
1148   if (pc->refresh_entropy_probs == 0) {
1149     memcpy(&pc->lfc, &pc->fc, sizeof(pc->fc));
1150   }
1151 
1152   pc->refresh_last_frame = pc->frame_type == KEY_FRAME || vp8_read_bit(bc);
1153 
1154 #if CONFIG_ERROR_CONCEALMENT
1155   /* Assume we should refresh the last frame if the bit is missing */
1156   xd->corrupted |= vp8dx_bool_error(bc);
1157   if (pbi->ec_active && xd->corrupted) pc->refresh_last_frame = 1;
1158 #endif
1159 
1160   if (0) {
1161     FILE *z = fopen("decodestats.stt", "a");
1162     fprintf(z, "%6d F:%d,G:%d,A:%d,L:%d,Q:%d\n", pc->current_video_frame,
1163             pc->frame_type, pc->refresh_golden_frame, pc->refresh_alt_ref_frame,
1164             pc->refresh_last_frame, pc->base_qindex);
1165     fclose(z);
1166   }
1167 
1168   {
1169     pbi->independent_partitions = 1;
1170 
1171     /* read coef probability tree */
1172     for (i = 0; i < BLOCK_TYPES; ++i) {
1173       for (j = 0; j < COEF_BANDS; ++j) {
1174         for (k = 0; k < PREV_COEF_CONTEXTS; ++k) {
1175           for (l = 0; l < ENTROPY_NODES; ++l) {
1176             vp8_prob *const p = pc->fc.coef_probs[i][j][k] + l;
1177 
1178             if (vp8_read(bc, vp8_coef_update_probs[i][j][k][l])) {
1179               *p = (vp8_prob)vp8_read_literal(bc, 8);
1180             }
1181             if (k > 0 && *p != pc->fc.coef_probs[i][j][k - 1][l]) {
1182               pbi->independent_partitions = 0;
1183             }
1184           }
1185         }
1186       }
1187     }
1188   }
1189 
1190   /* clear out the coeff buffer */
1191   memset(xd->qcoeff, 0, sizeof(xd->qcoeff));
1192 
1193   vp8_decode_mode_mvs(pbi);
1194 
1195 #if CONFIG_ERROR_CONCEALMENT
1196   if (pbi->ec_active &&
1197       pbi->mvs_corrupt_from_mb < (unsigned int)pc->mb_cols * pc->mb_rows) {
1198     /* Motion vectors are missing in this frame. We will try to estimate
1199      * them and then continue decoding the frame as usual */
1200     vp8_estimate_missing_mvs(pbi);
1201   }
1202 #endif
1203 
1204   memset(pc->above_context, 0, sizeof(ENTROPY_CONTEXT_PLANES) * pc->mb_cols);
1205   pbi->frame_corrupt_residual = 0;
1206 
1207 #if CONFIG_MULTITHREAD
1208   if (pbi->b_multithreaded_rd && pc->multi_token_partition != ONE_PARTITION) {
1209     unsigned int thread;
1210     vp8mt_decode_mb_rows(pbi, xd);
1211     vp8_yv12_extend_frame_borders(yv12_fb_new);
1212     for (thread = 0; thread < pbi->decoding_thread_count; ++thread) {
1213       corrupt_tokens |= pbi->mb_row_di[thread].mbd.corrupted;
1214     }
1215   } else
1216 #endif
1217   {
1218     decode_mb_rows(pbi);
1219     corrupt_tokens |= xd->corrupted;
1220   }
1221 
1222   /* Collect information about decoder corruption. */
1223   /* 1. Check first boolean decoder for errors. */
1224   yv12_fb_new->corrupted = vp8dx_bool_error(bc);
1225   /* 2. Check the macroblock information */
1226   yv12_fb_new->corrupted |= corrupt_tokens;
1227 
1228   if (!pbi->decoded_key_frame) {
1229     if (pc->frame_type == KEY_FRAME && !yv12_fb_new->corrupted) {
1230       pbi->decoded_key_frame = 1;
1231     } else {
1232       vpx_internal_error(&pbi->common.error, VPX_CODEC_CORRUPT_FRAME,
1233                          "A stream must start with a complete key frame");
1234     }
1235   }
1236 
1237   /* vpx_log("Decoder: Frame Decoded, Size Roughly:%d bytes
1238    * \n",bc->pos+pbi->bc2.pos); */
1239 
1240   if (pc->refresh_entropy_probs == 0) {
1241     memcpy(&pc->fc, &pc->lfc, sizeof(pc->fc));
1242     pbi->independent_partitions = prev_independent_partitions;
1243   }
1244 
1245 #ifdef PACKET_TESTING
1246   {
1247     FILE *f = fopen("decompressor.VP8", "ab");
1248     unsigned int size = pbi->bc2.pos + pbi->bc.pos + 8;
1249     fwrite((void *)&size, 4, 1, f);
1250     fwrite((void *)pbi->Source, size, 1, f);
1251     fclose(f);
1252   }
1253 #endif
1254 
1255   return 0;
1256 }
1257