FFmpeg/libavcodec/h264_sei.c
Anton Khirnov ec7f33a38e h264_sei: parse the picture timing SEIs correctly
Those SEIs refer to the currently active SPS. However, since the SEI
NALUs precede the coded picture data in the bitstream, the active SPS is
in general not known when we are decoding the SEI.

Therefore, store the content of the picture timing SEIs and actually
parse it when the active SPS is known.
2020-04-10 15:52:22 +02:00

542 lines
18 KiB
C

/*
* 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 / MPEG-4 part10 SEI decoding.
* @author Michael Niedermayer <michaelni@gmx.at>
*/
#include "avcodec.h"
#include "get_bits.h"
#include "golomb.h"
#include "h264_ps.h"
#include "h264_sei.h"
#include "internal.h"
#define AVERROR_PS_NOT_FOUND FFERRTAG(0xF8,'?','P','S')
static const uint8_t sei_num_clock_ts_table[9] = {
1, 1, 1, 2, 2, 3, 3, 2, 3
};
void ff_h264_sei_uninit(H264SEIContext *h)
{
h->recovery_point.recovery_frame_cnt = -1;
h->picture_timing.dpb_output_delay = 0;
h->picture_timing.cpb_removal_delay = -1;
h->picture_timing.present = 0;
h->buffering_period.present = 0;
h->frame_packing.present = 0;
h->display_orientation.present = 0;
h->afd.present = 0;
av_buffer_unref(&h->a53_caption.buf_ref);
}
int ff_h264_sei_process_picture_timing(H264SEIPictureTiming *h, const SPS *sps,
void *logctx)
{
GetBitContext gb;
init_get_bits(&gb, h->payload, h->payload_size_bits);
if (sps->nal_hrd_parameters_present_flag ||
sps->vcl_hrd_parameters_present_flag) {
h->cpb_removal_delay = get_bits_long(&gb, sps->cpb_removal_delay_length);
h->dpb_output_delay = get_bits_long(&gb, sps->dpb_output_delay_length);
}
if (sps->pic_struct_present_flag) {
unsigned int i, num_clock_ts;
h->pic_struct = get_bits(&gb, 4);
h->ct_type = 0;
if (h->pic_struct > H264_SEI_PIC_STRUCT_FRAME_TRIPLING)
return AVERROR_INVALIDDATA;
num_clock_ts = sei_num_clock_ts_table[h->pic_struct];
h->timecode_cnt = 0;
for (i = 0; i < num_clock_ts; i++) {
if (get_bits(&gb, 1)) { /* clock_timestamp_flag */
H264SEITimeCode *tc = &h->timecode[h->timecode_cnt++];
unsigned int full_timestamp_flag;
unsigned int counting_type, cnt_dropped_flag;
h->ct_type |= 1 << get_bits(&gb, 2);
skip_bits(&gb, 1); /* nuit_field_based_flag */
counting_type = get_bits(&gb, 5); /* counting_type */
full_timestamp_flag = get_bits(&gb, 1);
skip_bits(&gb, 1); /* discontinuity_flag */
cnt_dropped_flag = get_bits(&gb, 1); /* cnt_dropped_flag */
if (cnt_dropped_flag && counting_type > 1 && counting_type < 7)
tc->dropframe = 1;
tc->frame = get_bits(&gb, 8); /* n_frames */
if (full_timestamp_flag) {
tc->full = 1;
tc->seconds = get_bits(&gb, 6); /* seconds_value 0..59 */
tc->minutes = get_bits(&gb, 6); /* minutes_value 0..59 */
tc->hours = get_bits(&gb, 5); /* hours_value 0..23 */
} else {
tc->seconds = tc->minutes = tc->hours = tc->full = 0;
if (get_bits(&gb, 1)) { /* seconds_flag */
tc->seconds = get_bits(&gb, 6);
if (get_bits(&gb, 1)) { /* minutes_flag */
tc->minutes = get_bits(&gb, 6);
if (get_bits(&gb, 1)) /* hours_flag */
tc->hours = get_bits(&gb, 5);
}
}
}
if (sps->time_offset_length > 0)
skip_bits(&gb,
sps->time_offset_length); /* time_offset */
}
}
av_log(logctx, AV_LOG_DEBUG, "ct_type:%X pic_struct:%d\n",
h->ct_type, h->pic_struct);
}
return 0;
}
static int decode_picture_timing(H264SEIPictureTiming *h, GetBitContext *gb,
void *logctx)
{
int index = get_bits_count(gb);
int size_bits = get_bits_left(gb);
int size = (size_bits + 7) / 8;
if (index & 7) {
av_log(logctx, AV_LOG_ERROR, "Unaligned SEI payload\n");
return AVERROR_INVALIDDATA;
}
if (size > sizeof(h->payload)) {
av_log(logctx, AV_LOG_ERROR, "Picture timing SEI payload too large\n");
return AVERROR_INVALIDDATA;
}
memcpy(h->payload, gb->buffer + index / 8, size);
h->payload_size_bits = size_bits;
h->present = 1;
return 0;
}
static int decode_registered_user_data_afd(H264SEIAFD *h, GetBitContext *gb, int size)
{
int flag;
if (size-- < 1)
return AVERROR_INVALIDDATA;
skip_bits(gb, 1); // 0
flag = get_bits(gb, 1); // active_format_flag
skip_bits(gb, 6); // reserved
if (flag) {
if (size-- < 1)
return AVERROR_INVALIDDATA;
skip_bits(gb, 4); // reserved
h->active_format_description = get_bits(gb, 4);
h->present = 1;
}
return 0;
}
static int decode_registered_user_data_closed_caption(H264SEIA53Caption *h,
GetBitContext *gb, void *logctx,
int size)
{
int flag;
int user_data_type_code;
int cc_count;
if (size < 3)
return AVERROR(EINVAL);
user_data_type_code = get_bits(gb, 8);
if (user_data_type_code == 0x3) {
skip_bits(gb, 1); // reserved
flag = get_bits(gb, 1); // process_cc_data_flag
if (flag) {
skip_bits(gb, 1); // zero bit
cc_count = get_bits(gb, 5);
skip_bits(gb, 8); // reserved
size -= 2;
if (cc_count && size >= cc_count * 3) {
int old_size = h->buf_ref ? h->buf_ref->size : 0;
const uint64_t new_size = (old_size + cc_count
* UINT64_C(3));
int i, ret;
if (new_size > INT_MAX)
return AVERROR(EINVAL);
/* Allow merging of the cc data from two fields. */
ret = av_buffer_realloc(&h->buf_ref, new_size);
if (ret < 0)
return ret;
/* Use of av_buffer_realloc assumes buffer is writeable */
for (i = 0; i < cc_count; i++) {
h->buf_ref->data[old_size++] = get_bits(gb, 8);
h->buf_ref->data[old_size++] = get_bits(gb, 8);
h->buf_ref->data[old_size++] = get_bits(gb, 8);
}
skip_bits(gb, 8); // marker_bits
}
}
} else {
int i;
for (i = 0; i < size - 1; i++)
skip_bits(gb, 8);
}
return 0;
}
static int decode_registered_user_data(H264SEIContext *h, GetBitContext *gb,
void *logctx, int size)
{
uint32_t country_code;
uint32_t user_identifier;
if (size < 7)
return AVERROR_INVALIDDATA;
size -= 7;
country_code = get_bits(gb, 8); // itu_t_t35_country_code
if (country_code == 0xFF) {
skip_bits(gb, 8); // itu_t_t35_country_code_extension_byte
size--;
}
/* itu_t_t35_payload_byte follows */
skip_bits(gb, 8); // terminal provider code
skip_bits(gb, 8); // terminal provider oriented code
user_identifier = get_bits_long(gb, 32);
switch (user_identifier) {
case MKBETAG('D', 'T', 'G', '1'): // afd_data
return decode_registered_user_data_afd(&h->afd, gb, size);
case MKBETAG('G', 'A', '9', '4'): // closed captions
return decode_registered_user_data_closed_caption(&h->a53_caption, gb,
logctx, size);
default:
skip_bits(gb, size * 8);
break;
}
return 0;
}
static int decode_unregistered_user_data(H264SEIUnregistered *h, GetBitContext *gb,
void *logctx, int size)
{
uint8_t *user_data;
int e, build, i;
if (size < 16 || size >= INT_MAX - 1)
return AVERROR_INVALIDDATA;
user_data = av_malloc(size + 1);
if (!user_data)
return AVERROR(ENOMEM);
for (i = 0; i < size; i++)
user_data[i] = get_bits(gb, 8);
user_data[i] = 0;
e = sscanf(user_data + 16, "x264 - core %d", &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;
av_free(user_data);
return 0;
}
static int decode_recovery_point(H264SEIRecoveryPoint *h, GetBitContext *gb, void *logctx)
{
unsigned recovery_frame_cnt = get_ue_golomb_long(gb);
if (recovery_frame_cnt >= (1<<MAX_LOG2_MAX_FRAME_NUM)) {
av_log(logctx, AV_LOG_ERROR, "recovery_frame_cnt %u is out of range\n", recovery_frame_cnt);
return AVERROR_INVALIDDATA;
}
h->recovery_frame_cnt = recovery_frame_cnt;
/* 1b exact_match_flag,
* 1b broken_link_flag,
* 2b changing_slice_group_idc */
skip_bits(gb, 4);
return 0;
}
static int decode_buffering_period(H264SEIBufferingPeriod *h, GetBitContext *gb,
const H264ParamSets *ps, void *logctx)
{
unsigned int sps_id;
int sched_sel_idx;
const SPS *sps;
sps_id = get_ue_golomb_31(gb);
if (sps_id > 31 || !ps->sps_list[sps_id]) {
av_log(logctx, AV_LOG_ERROR,
"non-existing SPS %d referenced in buffering period\n", sps_id);
return sps_id > 31 ? AVERROR_INVALIDDATA : AVERROR_PS_NOT_FOUND;
}
sps = (const SPS*)ps->sps_list[sps_id]->data;
// 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(gb, sps->initial_cpb_removal_delay_length);
// initial_cpb_removal_delay_offset
skip_bits(gb, sps->initial_cpb_removal_delay_length);
}
}
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(gb, sps->initial_cpb_removal_delay_length);
// initial_cpb_removal_delay_offset
skip_bits(gb, sps->initial_cpb_removal_delay_length);
}
}
h->present = 1;
return 0;
}
static int decode_frame_packing_arrangement(H264SEIFramePacking *h,
GetBitContext *gb)
{
h->arrangement_id = get_ue_golomb_long(gb);
h->arrangement_cancel_flag = get_bits1(gb);
h->present = !h->arrangement_cancel_flag;
if (h->present) {
h->arrangement_type = get_bits(gb, 7);
h->quincunx_sampling_flag = get_bits1(gb);
h->content_interpretation_type = get_bits(gb, 6);
// spatial_flipping_flag, frame0_flipped_flag, field_views_flag
skip_bits(gb, 3);
h->current_frame_is_frame0_flag = get_bits1(gb);
// frame0_self_contained_flag, frame1_self_contained_flag
skip_bits(gb, 2);
if (!h->quincunx_sampling_flag && h->arrangement_type != 5)
skip_bits(gb, 16); // frame[01]_grid_position_[xy]
skip_bits(gb, 8); // frame_packing_arrangement_reserved_byte
h->arrangement_repetition_period = get_ue_golomb_long(gb);
}
skip_bits1(gb); // frame_packing_arrangement_extension_flag
return 0;
}
static int decode_display_orientation(H264SEIDisplayOrientation *h,
GetBitContext *gb)
{
h->present = !get_bits1(gb);
if (h->present) {
h->hflip = get_bits1(gb); // hor_flip
h->vflip = get_bits1(gb); // ver_flip
h->anticlockwise_rotation = get_bits(gb, 16);
get_ue_golomb_long(gb); // display_orientation_repetition_period
skip_bits1(gb); // display_orientation_extension_flag
}
return 0;
}
static int decode_green_metadata(H264SEIGreenMetaData *h, GetBitContext *gb)
{
h->green_metadata_type = get_bits(gb, 8);
if (h->green_metadata_type == 0) {
h->period_type = get_bits(gb, 8);
if (h->period_type == 2)
h->num_seconds = get_bits(gb, 16);
else if (h->period_type == 3)
h->num_pictures = get_bits(gb, 16);
h->percent_non_zero_macroblocks = get_bits(gb, 8);
h->percent_intra_coded_macroblocks = get_bits(gb, 8);
h->percent_six_tap_filtering = get_bits(gb, 8);
h->percent_alpha_point_deblocking_instance = get_bits(gb, 8);
} else if (h->green_metadata_type == 1) {
h->xsd_metric_type = get_bits(gb, 8);
h->xsd_metric_value = get_bits(gb, 16);
}
return 0;
}
static int decode_alternative_transfer(H264SEIAlternativeTransfer *h,
GetBitContext *gb)
{
h->present = 1;
h->preferred_transfer_characteristics = get_bits(gb, 8);
return 0;
}
int ff_h264_sei_decode(H264SEIContext *h, GetBitContext *gb,
const H264ParamSets *ps, void *logctx)
{
int master_ret = 0;
while (get_bits_left(gb) > 16 && show_bits(gb, 16)) {
GetBitContext gb_payload;
int type = 0;
unsigned size = 0;
int ret = 0;
do {
if (get_bits_left(gb) < 8)
return AVERROR_INVALIDDATA;
type += show_bits(gb, 8);
} while (get_bits(gb, 8) == 255);
do {
if (get_bits_left(gb) < 8)
return AVERROR_INVALIDDATA;
size += show_bits(gb, 8);
} while (get_bits(gb, 8) == 255);
if (size > get_bits_left(gb) / 8) {
av_log(logctx, AV_LOG_ERROR, "SEI type %d size %d truncated at %d\n",
type, 8*size, get_bits_left(gb));
return AVERROR_INVALIDDATA;
}
ret = init_get_bits8(&gb_payload, gb->buffer + get_bits_count(gb) / 8, size);
if (ret < 0)
return ret;
switch (type) {
case H264_SEI_TYPE_PIC_TIMING: // Picture timing SEI
ret = decode_picture_timing(&h->picture_timing, &gb_payload, logctx);
break;
case H264_SEI_TYPE_USER_DATA_REGISTERED:
ret = decode_registered_user_data(h, &gb_payload, logctx, size);
break;
case H264_SEI_TYPE_USER_DATA_UNREGISTERED:
ret = decode_unregistered_user_data(&h->unregistered, &gb_payload, logctx, size);
break;
case H264_SEI_TYPE_RECOVERY_POINT:
ret = decode_recovery_point(&h->recovery_point, &gb_payload, logctx);
break;
case H264_SEI_TYPE_BUFFERING_PERIOD:
ret = decode_buffering_period(&h->buffering_period, &gb_payload, ps, logctx);
break;
case H264_SEI_TYPE_FRAME_PACKING:
ret = decode_frame_packing_arrangement(&h->frame_packing, &gb_payload);
break;
case H264_SEI_TYPE_DISPLAY_ORIENTATION:
ret = decode_display_orientation(&h->display_orientation, &gb_payload);
break;
case H264_SEI_TYPE_GREEN_METADATA:
ret = decode_green_metadata(&h->green_metadata, &gb_payload);
break;
case H264_SEI_TYPE_ALTERNATIVE_TRANSFER:
ret = decode_alternative_transfer(&h->alternative_transfer, &gb_payload);
break;
default:
av_log(logctx, AV_LOG_DEBUG, "unknown SEI type %d\n", type);
}
if (ret < 0 && ret != AVERROR_PS_NOT_FOUND)
return ret;
if (ret < 0)
master_ret = ret;
if (get_bits_left(&gb_payload) < 0) {
av_log(logctx, AV_LOG_WARNING, "SEI type %d overread by %d bits\n",
type, -get_bits_left(&gb_payload));
}
skip_bits_long(gb, 8 * size);
}
return master_ret;
}
const char *ff_h264_sei_stereo_mode(const H264SEIFramePacking *h)
{
if (h->arrangement_cancel_flag == 0) {
switch (h->arrangement_type) {
case H264_SEI_FPA_TYPE_CHECKERBOARD:
if (h->content_interpretation_type == 2)
return "checkerboard_rl";
else
return "checkerboard_lr";
case H264_SEI_FPA_TYPE_INTERLEAVE_COLUMN:
if (h->content_interpretation_type == 2)
return "col_interleaved_rl";
else
return "col_interleaved_lr";
case H264_SEI_FPA_TYPE_INTERLEAVE_ROW:
if (h->content_interpretation_type == 2)
return "row_interleaved_rl";
else
return "row_interleaved_lr";
case H264_SEI_FPA_TYPE_SIDE_BY_SIDE:
if (h->content_interpretation_type == 2)
return "right_left";
else
return "left_right";
case H264_SEI_FPA_TYPE_TOP_BOTTOM:
if (h->content_interpretation_type == 2)
return "bottom_top";
else
return "top_bottom";
case H264_SEI_FPA_TYPE_INTERLEAVE_TEMPORAL:
if (h->content_interpretation_type == 2)
return "block_rl";
else
return "block_lr";
case H264_SEI_FPA_TYPE_2D:
default:
return "mono";
}
} else if (h->arrangement_cancel_flag == 1) {
return "mono";
} else {
return NULL;
}
}