diff options
| author | Tim Redfern <tim@eclectronics.org> | 2013-09-05 17:57:22 +0100 |
|---|---|---|
| committer | Tim Redfern <tim@eclectronics.org> | 2013-09-05 17:57:22 +0100 |
| commit | 8992cb1d0d07edc33d274f6d7924ecdf6f83d994 (patch) | |
| tree | 3a2c86846b7eec8137c1507e623fc7018f13d453 /ffmpeg/libavcodec/h264_sei.c | |
| parent | 741fb4b9e135cfb161a749db88713229038577bb (diff) | |
making act segmenter
Diffstat (limited to 'ffmpeg/libavcodec/h264_sei.c')
| -rw-r--r-- | ffmpeg/libavcodec/h264_sei.c | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/ffmpeg/libavcodec/h264_sei.c b/ffmpeg/libavcodec/h264_sei.c new file mode 100644 index 0000000..be6cb58 --- /dev/null +++ b/ffmpeg/libavcodec/h264_sei.c @@ -0,0 +1,251 @@ +/* + * H.26L/H.264/AVC/JVT/14496-10/... sei decoding + * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at> + * + * This file is part of FFmpeg. + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/** + * @file + * H.264 / AVC / MPEG4 part10 sei decoding. + * @author Michael Niedermayer <michaelni@gmx.at> + */ + +#include "internal.h" +#include "avcodec.h" +#include "h264.h" +#include "golomb.h" + +//#undef NDEBUG +#include <assert.h> + +static const uint8_t sei_num_clock_ts_table[9]={ + 1, 1, 1, 2, 2, 3, 3, 2, 3 +}; + +void ff_h264_reset_sei(H264Context *h) { + h->sei_recovery_frame_cnt = -1; + h->sei_dpb_output_delay = 0; + h->sei_cpb_removal_delay = -1; + h->sei_buffering_period_present = 0; +} + +static int decode_picture_timing(H264Context *h){ + if(h->sps.nal_hrd_parameters_present_flag || h->sps.vcl_hrd_parameters_present_flag){ + h->sei_cpb_removal_delay = get_bits_long(&h->gb, h->sps.cpb_removal_delay_length); + h->sei_dpb_output_delay = get_bits_long(&h->gb, h->sps.dpb_output_delay_length); + } + if(h->sps.pic_struct_present_flag){ + unsigned int i, num_clock_ts; + h->sei_pic_struct = get_bits(&h->gb, 4); + h->sei_ct_type = 0; + + if (h->sei_pic_struct > SEI_PIC_STRUCT_FRAME_TRIPLING) + return -1; + + num_clock_ts = sei_num_clock_ts_table[h->sei_pic_struct]; + + for (i = 0 ; i < num_clock_ts ; i++){ + if(get_bits(&h->gb, 1)){ /* clock_timestamp_flag */ + unsigned int full_timestamp_flag; + h->sei_ct_type |= 1<<get_bits(&h->gb, 2); + skip_bits(&h->gb, 1); /* nuit_field_based_flag */ + skip_bits(&h->gb, 5); /* counting_type */ + full_timestamp_flag = get_bits(&h->gb, 1); + skip_bits(&h->gb, 1); /* discontinuity_flag */ + skip_bits(&h->gb, 1); /* cnt_dropped_flag */ + skip_bits(&h->gb, 8); /* n_frames */ + if(full_timestamp_flag){ + skip_bits(&h->gb, 6); /* seconds_value 0..59 */ + skip_bits(&h->gb, 6); /* minutes_value 0..59 */ + skip_bits(&h->gb, 5); /* hours_value 0..23 */ + }else{ + if(get_bits(&h->gb, 1)){ /* seconds_flag */ + skip_bits(&h->gb, 6); /* seconds_value range 0..59 */ + if(get_bits(&h->gb, 1)){ /* minutes_flag */ + skip_bits(&h->gb, 6); /* minutes_value 0..59 */ + if(get_bits(&h->gb, 1)) /* hours_flag */ + skip_bits(&h->gb, 5); /* hours_value 0..23 */ + } + } + } + if(h->sps.time_offset_length > 0) + skip_bits(&h->gb, h->sps.time_offset_length); /* time_offset */ + } + } + + if(h->avctx->debug & FF_DEBUG_PICT_INFO) + av_log(h->avctx, AV_LOG_DEBUG, "ct_type:%X pic_struct:%d\n", h->sei_ct_type, h->sei_pic_struct); + } + return 0; +} + +static int decode_user_data_itu_t_t35(H264Context *h, int size) { + uint32_t user_identifier; + int dtg_active_format; + + if (size < 7) + return -1; + size -= 7; + + skip_bits(&h->gb, 8); // country_code + skip_bits(&h->gb, 16); // provider_code + user_identifier = get_bits_long(&h->gb, 32); + + switch (user_identifier) { + case 0x44544731: // "DTG1" - AFD_data + if (size < 1) + return -1; + skip_bits(&h->gb, 1); + if (get_bits(&h->gb, 1)) { + skip_bits(&h->gb, 6); + if (size < 2) + return -1; + skip_bits(&h->gb, 4); + dtg_active_format = get_bits(&h->gb, 4); + h->avctx->dtg_active_format = dtg_active_format; + } else { + skip_bits(&h->gb, 6); + } + break; + default: + skip_bits(&h->gb, size * 8); + break; + } + + return 0; +} + +static int decode_unregistered_user_data(H264Context *h, int size){ + uint8_t user_data[16+256]; + int e, build, i; + + if(size<16) + return -1; + + for(i=0; i<sizeof(user_data)-1 && i<size; i++){ + user_data[i]= get_bits(&h->gb, 8); + } + + user_data[i]= 0; + e= sscanf(user_data+16, "x264 - core %d"/*%s - H.264/MPEG-4 AVC codec - Copyleft 2005 - http://www.videolan.org/x264.html*/, &build); + if(e==1 && build>0) + h->x264_build= build; + if(e==1 && build==1 && !strncmp(user_data+16, "x264 - core 0000", 16)) + h->x264_build = 67; + + if(h->avctx->debug & FF_DEBUG_BUGS) + av_log(h->avctx, AV_LOG_DEBUG, "user data:\"%s\"\n", user_data+16); + + for(; i<size; i++) + skip_bits(&h->gb, 8); + + return 0; +} + +static int decode_recovery_point(H264Context *h){ + h->sei_recovery_frame_cnt = get_ue_golomb(&h->gb); + skip_bits(&h->gb, 4); /* 1b exact_match_flag, 1b broken_link_flag, 2b changing_slice_group_idc */ + + if(h->avctx->debug & FF_DEBUG_PICT_INFO) + av_log(h->avctx, AV_LOG_DEBUG, "sei_recovery_frame_cnt: %d\n", h->sei_recovery_frame_cnt); + + return 0; +} + +static int decode_buffering_period(H264Context *h){ + unsigned int sps_id; + int sched_sel_idx; + SPS *sps; + + sps_id = get_ue_golomb_31(&h->gb); + if(sps_id > 31 || !h->sps_buffers[sps_id]) { + av_log(h->avctx, AV_LOG_ERROR, "non-existing SPS %d referenced in buffering period\n", sps_id); + return -1; + } + sps = h->sps_buffers[sps_id]; + + // NOTE: This is really so duplicated in the standard... See H.264, D.1.1 + if (sps->nal_hrd_parameters_present_flag) { + for (sched_sel_idx = 0; sched_sel_idx < sps->cpb_cnt; sched_sel_idx++) { + h->initial_cpb_removal_delay[sched_sel_idx] = get_bits_long(&h->gb, sps->initial_cpb_removal_delay_length); + skip_bits(&h->gb, sps->initial_cpb_removal_delay_length); // initial_cpb_removal_delay_offset + } + } + if (sps->vcl_hrd_parameters_present_flag) { + for (sched_sel_idx = 0; sched_sel_idx < sps->cpb_cnt; sched_sel_idx++) { + h->initial_cpb_removal_delay[sched_sel_idx] = get_bits_long(&h->gb, sps->initial_cpb_removal_delay_length); + skip_bits(&h->gb, sps->initial_cpb_removal_delay_length); // initial_cpb_removal_delay_offset + } + } + + h->sei_buffering_period_present = 1; + return 0; +} + +int ff_h264_decode_sei(H264Context *h){ + while (get_bits_left(&h->gb) > 16) { + int size, type; + + type=0; + do{ + if (get_bits_left(&h->gb) < 8) + return -1; + type+= show_bits(&h->gb, 8); + }while(get_bits(&h->gb, 8) == 255); + + size=0; + do{ + if (get_bits_left(&h->gb) < 8) + return -1; + size+= show_bits(&h->gb, 8); + }while(get_bits(&h->gb, 8) == 255); + + if(h->avctx->debug&FF_DEBUG_STARTCODE) + av_log(h->avctx, AV_LOG_DEBUG, "SEI %d len:%d\n", type, size); + + switch(type){ + case SEI_TYPE_PIC_TIMING: // Picture timing SEI + if(decode_picture_timing(h) < 0) + return -1; + break; + case SEI_TYPE_USER_DATA_ITU_T_T35: + if(decode_user_data_itu_t_t35(h, size) < 0) + return -1; + break; + case SEI_TYPE_USER_DATA_UNREGISTERED: + if(decode_unregistered_user_data(h, size) < 0) + return -1; + break; + case SEI_TYPE_RECOVERY_POINT: + if(decode_recovery_point(h) < 0) + return -1; + break; + case SEI_BUFFERING_PERIOD: + if(decode_buffering_period(h) < 0) + return -1; + break; + default: + skip_bits(&h->gb, 8*size); + } + + //FIXME check bits here + align_get_bits(&h->gb); + } + + return 0; +} |
