void H264VideoStreamParser::analyze_hrd_parameters(BitVector& bv) { DEBUG_STR("BEGIN hrd_parameters"); unsigned cpb_cnt_minus1 = bv.get_expGolomb(); DEBUG_PRINT(cpb_cnt_minus1); unsigned bit_rate_scale = bv.getBits(4); DEBUG_PRINT(bit_rate_scale); unsigned cpb_size_scale = bv.getBits(4); DEBUG_PRINT(cpb_size_scale); for (unsigned SchedSelIdx = 0; SchedSelIdx <= cpb_cnt_minus1; ++SchedSelIdx) { DEBUG_TAB; unsigned bit_rate_value_minus1 = bv.get_expGolomb(); DEBUG_PRINT(bit_rate_value_minus1); unsigned cpb_size_value_minus1 = bv.get_expGolomb(); DEBUG_PRINT(cpb_size_value_minus1); unsigned cbr_flag = bv.get1Bit(); DEBUG_PRINT(cbr_flag); } unsigned initial_cpb_removal_delay_length_minus1 = bv.getBits(5); DEBUG_PRINT(initial_cpb_removal_delay_length_minus1); unsigned cpb_removal_delay_length_minus1 = bv.getBits(5); DEBUG_PRINT(cpb_removal_delay_length_minus1); unsigned dpb_output_delay_length_minus1 = bv.getBits(5); DEBUG_PRINT(dpb_output_delay_length_minus1); unsigned time_offset_length = bv.getBits(5); DEBUG_PRINT(time_offset_length); DEBUG_STR("END hrd_parameters"); }
/* do the huffman-decoding */ static int rsf_huffman_decoder(BitVector& bv, struct huffcodetab const* h, // ptr to huffman code record /* unsigned */ int *x, // returns decoded x value /* unsigned */ int *y, // returns decoded y value int* v, int* w) { HUFFBITS level; unsigned point = 0; int error = 1; level = dmask; *x = *y = *v = *w = 0; if (h->val == NULL) return 2; /* table 0 needs no bits */ if (h->treelen == 0) return 0; /* Lookup in Huffman table. */ do { if (h->val[point][0]==0) { /*end of tree*/ *x = h->val[point][1] >> 4; *y = h->val[point][1] & 0xf; error = 0; break; } if (bv.get1Bit()) { while (h->val[point][1] >= MXOFF) point += h->val[point][1]; point += h->val[point][1]; } else { while (h->val[point][0] >= MXOFF) point += h->val[point][0]; point += h->val[point][0]; } level >>= 1; } while (level || (point < h->treelen) );
void H264VideoStreamParser ::analyze_vui_parameters(BitVector& bv, unsigned& num_units_in_tick, unsigned& time_scale, unsigned& fixed_frame_rate_flag) { DEBUG_STR("BEGIN vui_parameters"); unsigned aspect_ratio_info_present_flag = bv.get1Bit(); DEBUG_PRINT(aspect_ratio_info_present_flag); if (aspect_ratio_info_present_flag) { DEBUG_TAB; unsigned aspect_ratio_idc = bv.getBits(8); DEBUG_PRINT(aspect_ratio_idc); if (aspect_ratio_idc == 255/*Extended_SAR*/) { bv.skipBits(32); // sar_width; sar_height } } unsigned overscan_info_present_flag = bv.get1Bit(); DEBUG_PRINT(overscan_info_present_flag); if (overscan_info_present_flag) { bv.skipBits(1); // overscan_appropriate_flag } unsigned video_signal_type_present_flag = bv.get1Bit(); DEBUG_PRINT(video_signal_type_present_flag); if (video_signal_type_present_flag) { DEBUG_TAB; bv.skipBits(4); // video_format; video_full_range_flag unsigned colour_description_present_flag = bv.get1Bit(); DEBUG_PRINT(colour_description_present_flag); if (colour_description_present_flag) { bv.skipBits(24); // colour_primaries; transfer_characteristics; matrix_coefficients } } unsigned chroma_loc_info_present_flag = bv.get1Bit(); DEBUG_PRINT(chroma_loc_info_present_flag); if (chroma_loc_info_present_flag) { (void)bv.get_expGolomb(); // chroma_sample_loc_type_top_field (void)bv.get_expGolomb(); // chroma_sample_loc_type_bottom_field } unsigned timing_info_present_flag = bv.get1Bit(); DEBUG_PRINT(timing_info_present_flag); if (timing_info_present_flag) { DEBUG_TAB; num_units_in_tick = bv.getBits(32); DEBUG_PRINT(num_units_in_tick); time_scale = bv.getBits(32); DEBUG_PRINT(time_scale); fixed_frame_rate_flag = bv.get1Bit(); DEBUG_PRINT(fixed_frame_rate_flag); } #ifdef DO_FULL_SPS_PARSING unsigned nal_hrd_parameters_present_flag = bv.get1Bit(); DEBUG_PRINT(nal_hrd_parameters_present_flag); if (nal_hrd_parameters_present_flag) { DEBUG_TAB; analyze_hrd_parameters(bv); } unsigned vcl_hrd_parameters_present_flag = bv.get1Bit(); DEBUG_PRINT(vcl_hrd_parameters_present_flag); if (vcl_hrd_parameters_present_flag) { DEBUG_TAB; analyze_hrd_parameters(bv); } if (nal_hrd_parameters_present_flag || vcl_hrd_parameters_present_flag) { bv.skipBits(1); // low_delay_hrd_flag } bv.skipBits(1); // pic_struct_present_flag unsigned bitstream_restriction_flag = bv.get1Bit(); DEBUG_PRINT(bitstream_restriction_flag); if (bitstream_restriction_flag) { bv.skipBits(1); // motion_vectors_over_pic_boundaries_flag (void)bv.get_expGolomb(); // max_bytes_per_pic_denom (void)bv.get_expGolomb(); // max_bits_per_mb_denom (void)bv.get_expGolomb(); // log2_max_mv_length_horizontal (void)bv.get_expGolomb(); // log2_max_mv_length_vertical (void)bv.get_expGolomb(); // num_reorder_frames (void)bv.get_expGolomb(); // max_dec_frame_buffering } DEBUG_STR("END vui_parameters"); #endif }