/* * Frontend Status Monitor plugin for the Video Disk Recorder * * See the README file for copyright information and how to reach the author. * */ #include "femontools.h" #include "femonh264.h" const cFemonH264::t_DAR cFemonH264::s_DAR[] = { { VIDEO_ASPECT_RATIO_1_1, 100 }, { VIDEO_ASPECT_RATIO_4_3, 133 }, { VIDEO_ASPECT_RATIO_16_9, 177 }, { VIDEO_ASPECT_RATIO_2_21_1, 221 }, { VIDEO_ASPECT_RATIO_12_11, 109 }, { VIDEO_ASPECT_RATIO_10_11, 90 }, { VIDEO_ASPECT_RATIO_16_11, 145 }, { VIDEO_ASPECT_RATIO_40_33, 121 }, { VIDEO_ASPECT_RATIO_24_11, 218 }, { VIDEO_ASPECT_RATIO_20_11, 181 }, { VIDEO_ASPECT_RATIO_32_11, 290 }, { VIDEO_ASPECT_RATIO_80_33, 242 }, { VIDEO_ASPECT_RATIO_18_11, 163 }, { VIDEO_ASPECT_RATIO_15_11, 136 }, { VIDEO_ASPECT_RATIO_64_33, 193 }, { VIDEO_ASPECT_RATIO_160_99, 161 }, { VIDEO_ASPECT_RATIO_3_2, 150 }, { VIDEO_ASPECT_RATIO_2_1, 200 } }; const cFemonH264::t_SAR cFemonH264::s_SAR[] = { { 0, 0 }, // VIDEO_ASPECT_RATIO_INVALID { 1, 1 }, // VIDEO_ASPECT_RATIO_1_1 { 12, 11 }, // VIDEO_ASPECT_RATIO_12_11 { 10, 11 }, // VIDEO_ASPECT_RATIO_10_11 { 16, 11 }, // VIDEO_ASPECT_RATIO_16_11 { 40, 33 }, // VIDEO_ASPECT_RATIO_40_33 { 24, 11 }, // VIDEO_ASPECT_RATIO_24_11 { 20, 11 }, // VIDEO_ASPECT_RATIO_20_11 { 32, 11 }, // VIDEO_ASPECT_RATIO_32_11 { 80, 33 }, // VIDEO_ASPECT_RATIO_80_33 { 18, 11 }, // VIDEO_ASPECT_RATIO_18_11 { 15, 11 }, // VIDEO_ASPECT_RATIO_15_11 { 64, 33 }, // VIDEO_ASPECT_RATIO_64_33 { 160, 99 }, // VIDEO_ASPECT_RATIO_160_99 { 4, 3 }, // VIDEO_ASPECT_RATIO_4_3 { 3, 2 }, // VIDEO_ASPECT_RATIO_3_2 { 2, 1 } // VIDEO_ASPECT_RATIO_2_1 }; const eVideoFormat cFemonH264::s_VideoFormats[] = { VIDEO_FORMAT_COMPONENT, VIDEO_FORMAT_PAL, VIDEO_FORMAT_NTSC, VIDEO_FORMAT_SECAM, VIDEO_FORMAT_MAC, VIDEO_FORMAT_UNKNOWN, VIDEO_FORMAT_RESERVED }; const uint8_t cFemonH264::s_SeiNumClockTsTable[9] = { 1, 1, 1, 2, 2, 3, 3, 2, 3 }; cFemonH264::cFemonH264(cFemonVideoIf *videohandler) : m_VideoHandler(videohandler), m_Width(0), m_Height(0), m_AspectRatio(VIDEO_ASPECT_RATIO_INVALID), m_Format(VIDEO_FORMAT_INVALID), m_FrameRate(0), m_BitRate(0), m_Scan(VIDEO_SCAN_INVALID), m_CpbDpbDelaysPresentFlag(false), m_PicStructPresentFlag(false), m_FrameMbsOnlyFlag(false), m_MbAdaptiveFrameFieldFlag(false), m_TimeOffsetLength(0) { reset(); } cFemonH264::~cFemonH264() { } bool cFemonH264::processVideo(const uint8_t *buf, int len) { uint8_t nal_data[len]; bool aud_found = false, sps_found = false, sei_found = true; // SEI temporarily disabled! const uint8_t *start = buf; const uint8_t *end = start + len; if (!m_VideoHandler) return false; // skip PES header if (!PesLongEnough(len)) return false; buf += PesPayloadOffset(buf); start = buf; reset(); for (;;) { int consumed = 0; buf = nextStartCode(buf, end); if (buf >= end) break; switch (buf[3] & 0x1F) { case NAL_AUD: if (!aud_found) { switch (buf[4] >> 5) { case 0: case 3: case 5: // I_FRAME //Dprintf("H.264: Found NAL AUD at offset %d/%d\n", int(buf - start), len); aud_found = true; break; case 1: case 4: case 6: // P_FRAME; case 2: case 7: // B_FRAME; default: // NO_PICTURE; break; } } break; case NAL_SPS: if (!sps_found) { //Dprintf("H.264: Found NAL SPS at offset %d/%d\n", int(buf - start), len); int nal_len = nalUnescape(nal_data, buf + 4, int(end - buf - 4)); consumed = parseSPS(nal_data, nal_len); if (consumed > 0) sps_found = true; } break; case NAL_SEI: if (!sei_found) { //Dprintf("H.264: Found NAL SEI at offset %d/%d\n", iny(buf - start), len); int nal_len = nalUnescape(nal_data, buf + 4, int(end - buf - 4)); consumed = parseSEI(nal_data, nal_len); if (consumed > 0) sei_found = true; } break; default: break; } if (aud_found && sps_found && sei_found) break; buf += consumed + 4; } if (aud_found) { m_VideoHandler->SetVideoCodec(VIDEO_CODEC_H264); if (sps_found) { //Dprintf("H.264 SPS: size %dx%d, aspect %d format %d framerate %.2f bitrate %.0f\n", m_Width, m_Height, m_AspectRatio, m_Format, m_FrameRate, m_BitRate); m_VideoHandler->SetVideoFormat(m_Format); m_VideoHandler->SetVideoSize(m_Width, m_Height); m_VideoHandler->SetVideoAspectRatio(m_AspectRatio); m_VideoHandler->SetVideoFramerate(m_FrameRate); m_VideoHandler->SetVideoBitrate(m_BitRate); } if (sei_found) { //Dprintf("H.264 SEI: scan %d\n", m_Scan); m_VideoHandler->SetVideoScan(m_Scan); } } return aud_found; } void cFemonH264::reset() { m_CpbDpbDelaysPresentFlag = false; m_PicStructPresentFlag = false; m_FrameMbsOnlyFlag = false; m_MbAdaptiveFrameFieldFlag = false; m_TimeOffsetLength = 0; } const uint8_t *cFemonH264::nextStartCode(const uint8_t *start, const uint8_t *end) { for (end -= 3; start < end; ++start) { if ((start[0] == 0x00) && (start[1] == 0x00) && (start[2] == 0x01)) return start; } return (end + 3); } int cFemonH264::nalUnescape(uint8_t *dst, const uint8_t *src, int len) { int s = 0, d = 0; while (s < len) { if (!src[s] && !src[s + 1]) { // hit 00 00 xx dst[d] = dst[d + 1] = 0; s += 2; d += 2; if (src[s] == 3) { s++; // 00 00 03 xx --> 00 00 xx if (s >= len) return d; } } dst[d++] = src[s++]; } return d; } int cFemonH264::parseSPS(const uint8_t *buf, int len) { int profile_idc, level_idc, constraint_set3_flag, pic_order_cnt_type, i, j; cBitStream bs(buf, len); uint32_t width = m_Width; uint32_t height = m_Height; eVideoAspectRatio aspect_ratio = m_AspectRatio; eVideoFormat format = m_Format; double frame_rate = m_FrameRate; double bit_rate = m_BitRate; bool cpb_dpb_delays_present_flag = m_CpbDpbDelaysPresentFlag; bool pic_struct_present_flag = m_PicStructPresentFlag; bool frame_mbs_only_flag = m_FrameMbsOnlyFlag; bool mb_adaptive_frame_field_flag = m_MbAdaptiveFrameFieldFlag; uint32_t time_offset_length = m_TimeOffsetLength; profile_idc = bs.getU8(); // profile_idc bs.skipBit(); // constraint_set0_flag bs.skipBit(); // constraint_set1_flag bs.skipBit(); // constraint_set2_flag constraint_set3_flag = bs.getBit(); // constraint_set3_flag bs.skipBits(4); // reserved_zero_4bits level_idc = bs.getU8(); // level_idc bs.skipUeGolomb(); // seq_parameter_set_id //Dprintf("H.264 SPS: profile_idc %d level_idc %d\n", profile_idc, level_idc); switch (profile_idc) { case 66: // baseline profile case 77: // main profile case 88: // extended profile switch (level_idc) { case 10: // level 1.0 bit_rate = 64000; break; case 11: // level 1b / 1.1 bit_rate = constraint_set3_flag ? 128000 : 192000; break; case 12: // level 1.2 bit_rate = 384000; break; case 13: // level 1.3 bit_rate = 768000; break; case 20: // level 2.0 bit_rate = 2000000; break; case 21: // level 2.1 bit_rate = 4000000; break; case 22: // level 2.2 bit_rate = 4000000; break; case 30: // level 3.0 bit_rate = 10000000; break; case 31: // level 3.1 bit_rate = 14000000; break; case 32: // level 3.2 bit_rate = 20000000; break; case 40: // level 4.0 bit_rate = 20000000; break; case 41: // level 4.1 bit_rate = 50000000; break; case 42: // level 4.2 bit_rate = 50000000; break; case 50: // level 5.0 bit_rate = 135000000; break; case 51: // level 5.1 bit_rate = 240000000; break; default: break; } break; case 100: // high profile switch (level_idc) { case 10: // level 1.0 bit_rate = 80000; break; case 11: // level 1b / 1.1 bit_rate = constraint_set3_flag ? 160000 : 240000; break; case 12: // level 1.2 bit_rate = 480000; break; case 13: // level 1.3 bit_rate = 960000; break; case 20: // level 2.0 bit_rate = 2500000; break; case 21: // level 2.1 bit_rate = 5000000; break; case 22: // level 2.2 bit_rate = 5000000; break; case 30: // level 3.0 bit_rate = 12500000; break; case 31: // level 3.1 bit_rate = 17500000; break; case 32: // level 3.2 bit_rate = 25000000; break; case 40: // level 4.0 bit_rate = 25000000; break; case 41: // level 4.1 bit_rate = 62500000; break; case 42: // level 4.2 bit_rate = 62500000; break; case 50: // level 5.0 bit_rate = 168750000; break; case 51: // level 5.1 bit_rate = 300000000; break; default: break; } break; case 110: // high 10 profile switch (level_idc) { case 10: // level 1.0 bit_rate = 192000; break; case 11: // level 1b / 1.1 bit_rate = constraint_set3_flag ? 384000 : 576000; break; case 12: // level 1.2 bit_rate = 115200; break; case 13: // level 1.3 bit_rate = 2304000; break; case 20: // level 2.0 bit_rate = 6000000; break; case 21: // level 2.1 bit_rate = 12000000; break; case 22: // level 2.2 bit_rate = 12000000; break; case 30: // level 3.0 bit_rate = 30000000; break; case 31: // level 3.1 bit_rate = 42000000; break; case 32: // level 3.2 bit_rate = 60000000; break; case 40: // level 4.0 bit_rate = 60000000; break; case 41: // level 4.1 bit_rate = 150000000; break; case 42: // level 4.2 bit_rate = 150000000; break; case 50: // level 5.0 bit_rate = 405000000; break; case 51: // level 5.1 bit_rate = 720000000; break; default: break; } break; case 122: // high 4:2:2 profile case 144: // high 4:4:4 profile switch (level_idc) { case 10: // level 1.0 bit_rate = 256000; break; case 11: // level 1b / 1.1 bit_rate = constraint_set3_flag ? 512000 : 768000; break; case 12: // level 1.2 bit_rate = 1536000; break; case 13: // level 1.3 bit_rate = 3072000; break; case 20: // level 2.0 bit_rate = 8000000; break; case 21: // level 2.1 bit_rate = 16000000; break; case 22: // level 2.2 bit_rate = 16000000; break; case 30: // level 3.0 bit_rate = 40000000; break; case 31: // level 3.1 bit_rate = 56000000; break; case 32: // level 3.2 bit_rate = 80000000; break; case 40: // level 4.0 bit_rate = 80000000; break; case 41: // level 4.1 bit_rate = 200000000; break; case 42: // level 4.2 bit_rate = 200000000; break; case 50: // level 5.0 bit_rate = 540000000; break; case 51: // level 5.1 bit_rate = 960000000; break; default: break; } break; default: break; } if ((profile_idc == 100) || (profile_idc == 110) || (profile_idc == 122) || (profile_idc == 144)) { if (bs.getUeGolomb() == 3) // chroma_format_idc bs.skipBit(); // residual_colour_transform_flag bs.skipUeGolomb(); // bit_depth_luma_minus8 bs.skipUeGolomb(); // bit_depth_chroma_minus8 bs.skipBit(); // qpprime_y_zero_transform_bypass_flag if (bs.getBit()) { // seq_scaling_matrix_present_flag for (i = 0; i < 8; ++i) { if (bs.getBit()) { // seq_scaling_list_present_flag[i] int last = 8, next = 8, size = (i < 6) ? 16 : 64; for (j = 0; j < size; ++j) { if (next) next = (last + bs.getSeGolomb()) & 0xff; last = next ?: last; } } } } } bs.skipUeGolomb(); // log2_max_frame_num_minus4 pic_order_cnt_type = bs.getUeGolomb(); // pic_order_cnt_type if (pic_order_cnt_type == 0) bs.skipUeGolomb(); // log2_max_pic_order_cnt_lsb_minus4 else if (pic_order_cnt_type == 1) { bs.skipBit(); // delta_pic_order_always_zero bs.skipSeGolomb(); // offset_for_non_ref_pic bs.skipSeGolomb(); // offset_for_top_to_bottom_field j = bs.getUeGolomb(); // num_ref_frames_in_pic_order_cnt_cycle for (i = 0; i < j; ++i) bs.skipSeGolomb(); // offset_for_ref_frame[i] } bs.skipUeGolomb(); // num_ref_frames bs.skipBit(); // gaps_in_frame_num_value_allowed_flag width = bs.getUeGolomb() + 1; // pic_width_in_mbs_minus1 height = bs.getUeGolomb() + 1; // pic_height_in_mbs_minus1 frame_mbs_only_flag = bs.getBit(); // frame_mbs_only_flag //Dprintf("H.264 SPS: pic_width: %u mbs\n", width); //Dprintf("H.264 SPS: pic_height: %u mbs\n", height); //Dprintf("H.264 SPS: frame only flag: %d\n", frame_mbs_only_flag); width *= 16; height *= 16 * (frame_mbs_only_flag ? 1 : 2); if (!frame_mbs_only_flag) mb_adaptive_frame_field_flag = bs.getBit(); // mb_adaptive_frame_field_flag bs.skipBit(); // direct_8x8_inference_flag if (bs.getBit()) { // frame_cropping_flag uint32_t crop_left, crop_right, crop_top, crop_bottom; crop_left = bs.getUeGolomb(); // frame_crop_left_offset crop_right = bs.getUeGolomb(); // frame_crop_rigth_offset crop_top = bs.getUeGolomb(); // frame_crop_top_offset crop_bottom = bs.getUeGolomb(); // frame_crop_bottom_offset //Dprintf("H.264 SPS: cropping %d %d %d %d\n", crop_left, crop_top, crop_right, crop_bottom); width -= 2 * (crop_left + crop_right); if (frame_mbs_only_flag) height -= 2 * (crop_top + crop_bottom); else height -= 4 * (crop_top + crop_bottom); } // VUI parameters if (bs.getBit()) { // vui_parameters_present_flag if (bs.getBit()) { // aspect_ratio_info_present uint32_t aspect_ratio_idc, sar_width = 0, sar_height = 0; aspect_ratio_idc = bs.getU8(); // aspect_ratio_idc //Dprintf("H.264 SPS: aspect_ratio_idc %d\n", aspect_ratio_idc); if (aspect_ratio_idc == 255) { // extended sar sar_width = bs.getU16(); // sar_width sar_height = bs.getU16(); // sar_height } else if (aspect_ratio_idc < ELEMENTS(s_SAR)) { sar_width = s_SAR[aspect_ratio_idc].w; sar_height = s_SAR[aspect_ratio_idc].h; } if (sar_width && sar_height) { int index = -1, ratio = 100.0L * sar_width * width / sar_height / height; for (unsigned int i = 0; i < ELEMENTS(s_DAR); ++i) { if (s_DAR[i].ratio == ratio) { index = i; break; } } if (index < 0) { if (aspect_ratio_idc == 255) aspect_ratio = VIDEO_ASPECT_RATIO_EXTENDED; else aspect_ratio = VIDEO_ASPECT_RATIO_INVALID; } else aspect_ratio = s_DAR[index].dar; //Dprintf("H.264 SPS: DAR %dx%d (%d)\n", sar_width, sar_height, aspect_ratio); } } if (bs.getBit()) // overscan_info_present_flag bs.skipBit(); // overscan_approriate_flag if (bs.getBit()) { // video_signal_type_present_flag uint32_t video_format; video_format = bs.getBits(3); // video_format if (video_format < sizeof(s_VideoFormats) / sizeof(s_VideoFormats[0])) { format = s_VideoFormats[video_format]; //Dprintf("H.264 SPS: video format %d\n", format); } bs.skipBit(); // video_full_range_flag if (bs.getBit()) { // colour_description_present_flag bs.skipBits(8); // colour_primaries bs.skipBits(8); // transfer_characteristics bs.skipBits(8); // matrix_coefficients } } if (bs.getBit()) { // chroma_loc_info_present_flag bs.skipUeGolomb(); // chroma_sample_loc_type_top_field bs.skipUeGolomb(); // chroma_sample_loc_type_bottom_field } if (bs.getBit()) { // timing_info_present_flag uint32_t num_units_in_tick, time_scale; num_units_in_tick = bs.getU32(); // num_units_in_tick time_scale = bs.getU32(); // time_scale if (num_units_in_tick > 0) frame_rate = time_scale / num_units_in_tick; bs.skipBit(); // fixed_frame_rate_flag } int nal_hrd_parameters_present_flag = bs.getBit(); // nal_hrd_parameters_present_flag if (nal_hrd_parameters_present_flag) { int cpb_cnt_minus1; cpb_cnt_minus1 = bs.getUeGolomb(); // cpb_cnt_minus1 bs.skipBits(4); // bit_rate_scale bs.skipBits(4); // cpb_size_scale for (int i = 0; i < cpb_cnt_minus1; ++i) { bs.skipUeGolomb(); // bit_rate_value_minus1[i] bs.skipUeGolomb(); // cpb_size_value_minus1[i] bs.skipBit(); // cbr_flag[i] } bs.skipBits(5); // initial_cpb_removal_delay_length_minus1 bs.skipBits(5); // cpb_removal_delay_length_minus1 bs.skipBits(5); // dpb_output_delay_length_minus1 time_offset_length = bs.getBits(5); // time_offset_length } int vlc_hrd_parameters_present_flag = bs.getBit(); // vlc_hrd_parameters_present_flag if (vlc_hrd_parameters_present_flag) { int cpb_cnt_minus1; cpb_cnt_minus1 = bs.getUeGolomb(); // cpb_cnt_minus1 bs.skipBits(4); // bit_rate_scale bs.skipBits(4); // cpb_size_scale for (int i = 0; i < cpb_cnt_minus1; ++i) { bs.skipUeGolomb(); // bit_rate_value_minus1[i] bs.skipUeGolomb(); // cpb_size_value_minus1[i] bs.skipBit(); // cbr_flag[i] } bs.skipBits(5); // initial_cpb_removal_delay_length_minus1 bs.skipBits(5); // cpb_removal_delay_length_minus1 bs.skipBits(5); // dpb_output_delay_length_minus1 time_offset_length = bs.getBits(5);// time_offset_length } cpb_dpb_delays_present_flag = (nal_hrd_parameters_present_flag | vlc_hrd_parameters_present_flag); if (cpb_dpb_delays_present_flag) bs.skipBit(); // low_delay_hrd_flag pic_struct_present_flag = bs.getBit(); // pic_struct_present_flag if (bs.getBit()) { // bitstream_restriction_flag bs.skipBit(); // motion_vectors_over_pic_boundaries_flag bs.skipUeGolomb(); // max_bytes_per_pic_denom bs.skipUeGolomb(); // max_bits_per_mb_denom bs.skipUeGolomb(); // log2_max_mv_length_horizontal bs.skipUeGolomb(); // log2_max_mv_length_vertical bs.skipUeGolomb(); // num_reorder_frames bs.skipUeGolomb(); // max_dec_frame_buffering } } m_Width = width; m_Height = height; m_AspectRatio = aspect_ratio; m_Format = format; m_FrameRate = frame_rate; m_BitRate = bit_rate; m_CpbDpbDelaysPresentFlag = cpb_dpb_delays_present_flag; m_PicStructPresentFlag = pic_struct_present_flag; m_FrameMbsOnlyFlag = frame_mbs_only_flag; m_MbAdaptiveFrameFieldFlag = mb_adaptive_frame_field_flag; m_TimeOffsetLength = time_offset_length; return (bs.getIndex() / 8); } int cFemonH264::parseSEI(const uint8_t *buf, int len) { int num_referenced_subseqs, i; cBitStream bs(buf, len); eVideoScan scan = m_Scan; while ((bs.getIndex() * 8 + 16) < len) { // sei_message int lastByte, payloadSize = 0, payloadType = 0; do { lastByte = bs.getU8() & 0xFF; payloadType += lastByte; } while (lastByte == 0xFF); // last_payload_type_byte do { lastByte = bs.getU8() & 0xFF; payloadSize += lastByte; } while (lastByte == 0xFF); // last_payload_size_byte switch (payloadType) { // sei_payload case 1: // pic_timing if (m_CpbDpbDelaysPresentFlag) { // cpb_dpb_delays_present_flag bs.skipUeGolomb(); // cpb_removal_delay bs.skipUeGolomb(); // dpb_output_delay } if (m_PicStructPresentFlag) { // pic_struct_present_flag uint32_t pic_struct; pic_struct = bs.getBits(4); // pic_struct if (pic_struct >= (sizeof(s_SeiNumClockTsTable)) / sizeof(s_SeiNumClockTsTable[0])) return 0; if (m_FrameMbsOnlyFlag && !m_MbAdaptiveFrameFieldFlag) scan = VIDEO_SCAN_PROGRESSIVE; else { switch (pic_struct) { case 0: // frame case 7: // frame doubling case 8: // frame tripling scan = VIDEO_SCAN_PROGRESSIVE; break; case 1: // top case 2: // bottom case 3: // top bottom case 4: // bottom top case 5: // top bottom top case 6: // bottom top bottom scan = VIDEO_SCAN_INTERLACED; break; default: scan = VIDEO_SCAN_RESERVED; break; } } //Dprintf("H.264 SEI: pic struct %d scan type %d\n", pic_struct, scan); for (int i = 0; i < s_SeiNumClockTsTable[pic_struct]; ++i) { if (bs.getBit()) { // clock_timestamp_flag[i] int full_timestamp_flag; switch (bs.getBits(2)) { // ct_type case 0: scan = VIDEO_SCAN_PROGRESSIVE; break; case 1: scan = VIDEO_SCAN_INTERLACED; break; case 2: scan = VIDEO_SCAN_UNKNOWN; break; default: scan = VIDEO_SCAN_RESERVED; break; } //Dprintf("H.264 SEI: scan type %d\n", scan); bs.skipBit(); // nuit_field_based_flag bs.skipBits(5); // counting_type full_timestamp_flag = bs.getBit(); // full_timestamp_flag bs.skipBit(); // discontinuity_flag bs.skipBit(); // cnt_dropped_flag bs.skipBits(8); // n_frames if (full_timestamp_flag) { bs.skipBits(6); // seconds_value bs.skipBits(6); // minutes_value bs.skipBits(5); // hours_value } else { if (bs.getBit()) { // seconds_flag bs.skipBits(6); // seconds_value if (bs.getBit()) { // minutes_flag bs.skipBits(6); // minutes_value if (bs.getBit()) // hours_flag bs.skipBits(5); // hours_value } } } if (m_TimeOffsetLength > 0) bs.skipBits(m_TimeOffsetLength); // time_offset } } } break; case 12: // sub_seq_characteristics bs.skipUeGolomb(); // sub_seq_layer_num bs.skipUeGolomb(); // sub_seq_id if (bs.getBit()) // duration_flag bs.skipBits(32); // sub_seq_duration if (bs.getBit()) { // average_rate_flag bs.skipBit(); // accurate_statistics_flag bs.skipBits(16); // average_bit_rate (1000 bit/s) bs.skipBits(16); // average_frame_rate (frames per 256s) } num_referenced_subseqs = bs.getUeGolomb(); // num_referenced_subseqs for (i = 0; i < num_referenced_subseqs; ++i) { bs.skipUeGolomb(); // ref_sub_seq_layer_num bs.skipUeGolomb(); // ref_sub_seq_id bs.getBit(); // ref_sub_seq_direction } break; default: bs.skipBits(payloadSize * 8); break; } // force byte align bs.byteAlign(); } m_Scan = scan; return (bs.getIndex() / 8); }