static const uint8_t *decode_nal(H264Context *h, const uint8_t *src, int *dst_length, int *consumed, int length){ int i, si, di; uint8_t *dst; int bufidx; // src[0]&0x80; //forbidden bit h->nal_ref_idc= src[0]>>5; h->nal_unit_type= src[0]&0x1F; src++; length--; #if 0 for(i=0; i<length; i++) printf("%2X ", src[i]); #endif for(i=0; i+1<length; i+=2){ if(src[i]) continue; if(i>0 && src[i-1]==0) i--; if(i+2<length && src[i+1]==0 && src[i+2]<=3){ if(src[i+2]!=3){ /* startcode, so we must be past the end */ length=i; } break; } } if(i>=length-1){ //no escaped 0 *dst_length= length; *consumed= length+1; //+1 for the header return src; } bufidx = h->nal_unit_type == NAL_DPC ? 1 : 0; // use second escape buffer for inter data h->rbsp_buffer[bufidx]= av_fast_realloc(h->rbsp_buffer[bufidx], &h->rbsp_buffer_size[bufidx], length); dst= h->rbsp_buffer[bufidx]; if (dst == NULL){ return NULL; } //printf("decoding esc\n"); si=di=0; while(si<length){ //remove escapes (very rare 1:2^22) if(si+2<length && src[si]==0 && src[si+1]==0 && src[si+2]<=3){ if(src[si+2]==3){ //escape dst[di++]= 0; dst[di++]= 0; si+=3; continue; }else //next start code break; } dst[di++]= src[si++]; } *dst_length= di; *consumed= si + 1;//+1 for the header //FIXME store exact number of bits in the getbitcontext (it is needed for decoding) return dst; }