/*! ************************************************************************ * \brief * Read the next NAL unit (with error handling) ************************************************************************ */ int read_next_nalu(VideoParameters *p_Vid, NALU_t *nalu) { InputParameters *p_Inp = p_Vid->p_Inp; int ret; switch( p_Inp->FileFormat ) { default: case PAR_OF_ANNEXB: ret = get_annex_b_NALU(p_Vid, nalu, p_Vid->annex_b); break; case PAR_OF_RTP: ret = GetRTPNALU(p_Vid, nalu, p_Vid->BitStreamFile); break; } if (ret < 0) { snprintf (errortext, ET_SIZE, "Error while getting the NALU in file format %s, exit\n", p_Inp->FileFormat==PAR_OF_ANNEXB?"Annex B":"RTP"); error (errortext, 601); } if (ret == 0) { //FreeNALU(nalu); return 0; } //In some cases, zero_byte shall be present. If current NALU is a VCL NALU, we can't tell //whether it is the first VCL NALU at this point, so only non-VCL NAL unit is checked here. CheckZeroByteNonVCL(p_Vid, nalu); ret = NALUtoRBSP(nalu); if (ret < 0) error ("Invalid startcode emulation prevention found.", 602); // Got a NALU if (nalu->forbidden_bit) { error ("Found NALU with forbidden_bit set, bit error?", 603); } return nalu->len; }
/*! ************************************************************************ * \brief * Reads new slice from bit_stream ************************************************************************ */ int read_new_slice() { NALU_t *nalu = AllocNALU(MAX_CODED_FRAME_SIZE); int current_header; int ret; int BitsUsedByHeader; Slice *currSlice = img->currentSlice; Bitstream *currStream; int newframe; int slice_id_a, slice_id_b, slice_id_c; int redundant_pic_cnt_a, redundant_pic_cnt_b, redundant_pic_cnt_c; long ftell_position, expected_slice_type; // int i; expected_slice_type = NALU_TYPE_DPA; while (1) { ftell_position = ftell(bits); if (input->FileFormat == PAR_OF_ANNEXB) ret=GetAnnexbNALU (nalu); else ret=GetRTPNALU (nalu); NALUtoRBSP(nalu); // printf ("nalu->len %d\n", nalu->len); if (ret < 0) printf ("Error while getting the NALU in file format %s, exit\n", input->FileFormat==PAR_OF_ANNEXB?"Annex B":"RTP"); if (ret == 0) { // printf ("read_new_slice: returning %s\n", "EOS"); if(expected_slice_type != NALU_TYPE_DPA) { /* oops... we found the next slice, go back! */ fseek(bits, ftell_position, SEEK_SET); FreeNALU(nalu); return current_header; } else return EOS; } // Got a NALU if (nalu->forbidden_bit) { printf ("Found NALU w/ forbidden_bit set, bit error? Let's try...\n"); } switch (nalu->nal_unit_type) { case NALU_TYPE_SLICE: case NALU_TYPE_IDR: img->idr_flag = (nalu->nal_unit_type == NALU_TYPE_IDR); img->nal_reference_idc = nalu->nal_reference_idc; img->disposable_flag = (nalu->nal_reference_idc == NALU_PRIORITY_DISPOSABLE); currSlice->dp_mode = PAR_DP_1; currSlice->max_part_nr = 1; currSlice->ei_flag = 0; currStream = currSlice->partArr[0].bitstream; currStream->ei_flag = 0; currStream->frame_bitoffset = currStream->read_len = 0; memcpy (currStream->streamBuffer, &nalu->buf[1], nalu->len-1); currStream->code_len = currStream->bitstream_length = RBSPtoSODB(currStream->streamBuffer, nalu->len-1); // Some syntax of the Slice Header depends on the parameter set, which depends on // the parameter set ID of the SLice header. Hence, read the pic_parameter_set_id // of the slice header first, then setup the active parameter sets, and then read // the rest of the slice header BitsUsedByHeader = FirstPartOfSliceHeader(); UseParameterSet (currSlice->pic_parameter_set_id); BitsUsedByHeader+= RestOfSliceHeader (); FmoInit (active_pps, active_sps); init_lists(img->type, img->currentSlice->structure); reorder_lists (img->type, img->currentSlice); /* if (img->frame_num==1) // write a reference list { count ++; if (count==1) for (i=0; i<listXsize[0]; i++) write_picture(listX[0][i], p_out2); } */ if (img->MbaffFrameFlag) { init_mbaff_lists(); } if (img->currentSlice->structure!=0) { img->height /=2 ; img->height_cr /=2; } // From here on, active_sps, active_pps and the slice header are valid img->current_mb_nr = currSlice->start_mb_nr; if (img->tr_old != img->ThisPOC) { newframe=1; img->tr_old = img->ThisPOC; } else newframe = 0; if (newframe) current_header = SOP; else current_header = SOS; if(img->structure != img->structure_old) newframe |= 1; img->structure_old = img->structure; //! new stuff StW if(newframe || g_new_frame) { current_header = SOP; g_new_frame=0; } else current_header = SOS; if (active_pps->entropy_coding_mode_flag) { int ByteStartPosition = currStream->frame_bitoffset/8; if (currStream->frame_bitoffset%8 != 0) { ByteStartPosition++; } arideco_start_decoding (&currSlice->partArr[0].de_cabac, currStream->streamBuffer, ByteStartPosition, &currStream->read_len, img->type); } // printf ("read_new_slice: returning %s\n", current_header == SOP?"SOP":"SOS"); FreeNALU(nalu); return current_header; break; case NALU_TYPE_DPA: //! The state machine here should follow the same ideas as the old readSliceRTP() //! basically: //! work on DPA (as above) //! read and process all following SEI/SPS/PPS/PD/Filler NALUs //! if next video NALU is dpB, //! then read and check whether it belongs to DPA, if yes, use it //! else //! ; // nothing //! read and process all following SEI/SPS/PPS/PD/Filler NALUs //! if next video NALU is dpC //! then read and check whether it belongs to DPA (and DPB, if present), if yes, use it, done //! else //! use the DPA (and the DPB if present) /* LC: inserting the code related to DP processing, mainly copying some of the parts related to NALU_TYPE_SLICE, NALU_TYPE_IDR. */ if(expected_slice_type != NALU_TYPE_DPA) { /* oops... we found the next slice, go back! */ fseek(bits, ftell_position, SEEK_SET); FreeNALU(nalu); return current_header; } img->idr_flag = (nalu->nal_unit_type == NALU_TYPE_IDR); img->nal_reference_idc = nalu->nal_reference_idc; img->disposable_flag = (nalu->nal_reference_idc == NALU_PRIORITY_DISPOSABLE); currSlice->dp_mode = PAR_DP_3; currSlice->max_part_nr = 3; currSlice->ei_flag = 0; currStream = currSlice->partArr[0].bitstream; currStream->ei_flag = 0; currStream->frame_bitoffset = currStream->read_len = 0; memcpy (currStream->streamBuffer, &nalu->buf[1], nalu->len-1); currStream->code_len = currStream->bitstream_length = RBSPtoSODB(currStream->streamBuffer, nalu->len-1); BitsUsedByHeader = FirstPartOfSliceHeader(); UseParameterSet (currSlice->pic_parameter_set_id); BitsUsedByHeader += RestOfSliceHeader (); FmoInit (active_pps, active_sps); init_lists(img->type, img->currentSlice->structure); reorder_lists (img->type, img->currentSlice); if (img->MbaffFrameFlag) { init_mbaff_lists(); } if (img->currentSlice->structure!=0) { img->height /=2 ; img->height_cr /=2; } // From here on, active_sps, active_pps and the slice header are valid img->current_mb_nr = currSlice->start_mb_nr; if (img->tr_old != img->ThisPOC) { newframe=1; img->tr_old = img->ThisPOC; } else newframe = 0; if (newframe) current_header = SOP; else current_header = SOS; if(img->structure != img->structure_old) newframe |= 1; img->structure_old = img->structure; //! new stuff StW if(newframe || g_new_frame) { current_header = SOP; g_new_frame=0; } else current_header = SOS; /* LC: Now I need to read the slice ID, which depends on the value of redundant_pic_cnt_present_flag (pag.49). */ slice_id_a = ue_v("NALU:SLICE_A slice_idr", currStream); if (active_pps->redundant_pic_cnt_present_flag) redundant_pic_cnt_a = ue_v("NALU:SLICE_A redudand_pic_cnt", currStream); else redundant_pic_cnt_a = 0; if (active_pps->entropy_coding_mode_flag) { int ByteStartPosition = currStream->frame_bitoffset/8; if (currStream->frame_bitoffset%8 != 0) { ByteStartPosition++; } arideco_start_decoding (&currSlice->partArr[0].de_cabac, currStream->streamBuffer, ByteStartPosition, &currStream->read_len, img->type); } // printf ("read_new_slice: returning %s\n", current_header == SOP?"SOP":"SOS"); break; case NALU_TYPE_DPB: /* LC: inserting the code related to DP processing */ currStream = currSlice->partArr[1].bitstream; currStream->ei_flag = 0; currStream->frame_bitoffset = currStream->read_len = 0; memcpy (currStream->streamBuffer, &nalu->buf[1], nalu->len-1); currStream->code_len = currStream->bitstream_length = RBSPtoSODB(currStream->streamBuffer, nalu->len-1); slice_id_b = ue_v("NALU:SLICE_B slice_idr", currStream); if (active_pps->redundant_pic_cnt_present_flag) redundant_pic_cnt_b = ue_v("NALU:SLICE_B redudand_pic_cnt", currStream); else redundant_pic_cnt_b = 0; /* LC: Initializing CABAC for the current data stream. */ if (active_pps->entropy_coding_mode_flag) { int ByteStartPosition = currStream->frame_bitoffset/8; if (currStream->frame_bitoffset % 8 != 0) ByteStartPosition++; arideco_start_decoding (&currSlice->partArr[1].de_cabac, currStream->streamBuffer, ByteStartPosition, &currStream->read_len, img->type); } /* LC: resilience code to be inserted */ /* FreeNALU(nalu); */ /* return current_header; */ break; case NALU_TYPE_DPC: /* LC: inserting the code related to DP processing */ currStream = currSlice->partArr[2].bitstream; currStream->ei_flag = 0; currStream->frame_bitoffset = currStream->read_len = 0; memcpy (currStream->streamBuffer, &nalu->buf[1], nalu->len-1); currStream->code_len = currStream->bitstream_length = RBSPtoSODB(currStream->streamBuffer, nalu->len-1); slice_id_c = ue_v("NALU:SLICE_C slice_idr", currStream); if (active_pps->redundant_pic_cnt_present_flag) redundant_pic_cnt_c = ue_v("NALU:SLICE_C redudand_pic_cnt", currStream); else redundant_pic_cnt_c = 0; /* LC: Initializing CABAC for the current data stream. */ if (active_pps->entropy_coding_mode_flag) { int ByteStartPosition = currStream->frame_bitoffset/8; if (currStream->frame_bitoffset % 8 != 0) ByteStartPosition++; arideco_start_decoding (&currSlice->partArr[2].de_cabac, currStream->streamBuffer, ByteStartPosition, &currStream->read_len, img->type); } /* LC: resilience code to be inserted */ FreeNALU(nalu); return current_header; break; case NALU_TYPE_SEI: printf ("read_new_slice: Found NALU_TYPE_SEI, len %d\n", nalu->len); InterpretSEIMessage(nalu->buf,nalu->len,img); break; case NALU_TYPE_PPS: ProcessPPS(nalu); break; case NALU_TYPE_SPS: ProcessSPS(nalu); break; case NALU_TYPE_PD: // printf ("read_new_slice: Found 'Access Unit Delimiter' NAL unit, len %d, ignored\n", nalu->len); break; case NALU_TYPE_EOSEQ: // printf ("read_new_slice: Found 'End of Sequence' NAL unit, len %d, ignored\n", nalu->len); break; case NALU_TYPE_EOSTREAM: // printf ("read_new_slice: Found 'End of Stream' NAL unit, len %d, ignored\n", nalu->len); break; case NALU_TYPE_FILL: printf ("read_new_slice: Found NALU_TYPE_FILL, len %d\n", nalu->len); printf ("Skipping these filling bits, proceeding w/ next NALU\n"); break; default: printf ("Found NALU type %d, len %d undefined, ignore NALU, moving on\n", nalu->nal_unit_type, nalu->len); } } FreeNALU(nalu); return current_header; }