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FFmpeg/libavcodec/h264_sei.c
Andreas Rheinhardt 787351a68e avcodec/h264_ps: Use RefStruct API for SPS/PPS
Avoids allocations and error checks for these allocations;
e.g. syncing buffers across threads can't fail any more
and needn't be checked. It also avoids having to keep
H264ParamSets.pps and H264ParamSets.pps_ref and PPS.sps
and PPS.sps_ref in sync and gets rid of casts and indirections.

(The removal of these checks and the syncing code even more
than offset the additional code for RefStruct.)

Reviewed-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2023-10-07 22:34:20 +02:00

350 lines
12 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 <limits.h>
#include <stdio.h>
#include <string.h>
#include "libavutil/error.h"
#include "libavutil/log.h"
#include "libavutil/macros.h"
#include "libavutil/mem.h"
#include "bytestream.h"
#include "get_bits.h"
#include "golomb.h"
#include "h264_ps.h"
#include "h264_sei.h"
#include "sei.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->common.frame_packing.present = 0;
h->common.film_grain_characteristics.present = 0;
h->common.display_orientation.present = 0;
h->common.afd.present = 0;
ff_h2645_sei_reset(&h->common);
}
int ff_h264_sei_process_picture_timing(H264SEIPictureTiming *h, const SPS *sps,
void *logctx)
{
GetBitContext gb;
av_unused int ret;
ret = init_get_bits8(&gb, h->payload, h->payload_size_bytes);
av_assert1(ret >= 0);
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, GetByteContext *gb,
void *logctx)
{
int size = bytestream2_get_bytes_left(gb);
if (size > sizeof(h->payload)) {
av_log(logctx, AV_LOG_ERROR, "Picture timing SEI payload too large\n");
return AVERROR_INVALIDDATA;
}
bytestream2_get_bufferu(gb, h->payload, size);
h->payload_size_bytes = size;
h->present = 1;
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 = ps->sps_list[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(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_green_metadata(H264SEIGreenMetaData *h, GetByteContext *gb)
{
h->green_metadata_type = bytestream2_get_byte(gb);
if (h->green_metadata_type == 0) {
h->period_type = bytestream2_get_byte(gb);
if (h->period_type == 2)
h->num_seconds = bytestream2_get_be16(gb);
else if (h->period_type == 3)
h->num_pictures = bytestream2_get_be16(gb);
h->percent_non_zero_macroblocks = bytestream2_get_byte(gb);
h->percent_intra_coded_macroblocks = bytestream2_get_byte(gb);
h->percent_six_tap_filtering = bytestream2_get_byte(gb);
h->percent_alpha_point_deblocking_instance = bytestream2_get_byte(gb);
} else if (h->green_metadata_type == 1) {
h->xsd_metric_type = bytestream2_get_byte(gb);
h->xsd_metric_value = bytestream2_get_be16(gb);
}
return 0;
}
int ff_h264_sei_decode(H264SEIContext *h, GetBitContext *gb,
const H264ParamSets *ps, void *logctx)
{
GetByteContext gbyte;
int master_ret = 0;
av_assert1((get_bits_count(gb) % 8) == 0);
bytestream2_init(&gbyte, gb->buffer + get_bits_count(gb) / 8,
get_bits_left(gb) / 8);
while (bytestream2_get_bytes_left(&gbyte) > 2 && bytestream2_peek_ne16(&gbyte)) {
GetByteContext gbyte_payload;
GetBitContext gb_payload;
int type = 0;
unsigned size = 0;
int ret = 0;
do {
if (bytestream2_get_bytes_left(&gbyte) <= 0)
return AVERROR_INVALIDDATA;
type += bytestream2_peek_byteu(&gbyte);
} while (bytestream2_get_byteu(&gbyte) == 255);
do {
if (bytestream2_get_bytes_left(&gbyte) <= 0)
return AVERROR_INVALIDDATA;
size += bytestream2_peek_byteu(&gbyte);
} while (bytestream2_get_byteu(&gbyte) == 255);
if (size > bytestream2_get_bytes_left(&gbyte)) {
av_log(logctx, AV_LOG_ERROR, "SEI type %d size %d truncated at %d\n",
type, size, bytestream2_get_bytes_left(&gbyte));
return AVERROR_INVALIDDATA;
}
bytestream2_init (&gbyte_payload, gbyte.buffer, size);
ret = init_get_bits8(&gb_payload, gbyte.buffer, size);
if (ret < 0)
return ret;
switch (type) {
case SEI_TYPE_PIC_TIMING: // Picture timing SEI
ret = decode_picture_timing(&h->picture_timing, &gbyte_payload, logctx);
break;
case SEI_TYPE_RECOVERY_POINT:
ret = decode_recovery_point(&h->recovery_point, &gb_payload, logctx);
break;
case SEI_TYPE_BUFFERING_PERIOD:
ret = decode_buffering_period(&h->buffering_period, &gb_payload, ps, logctx);
break;
case SEI_TYPE_GREEN_METADATA:
ret = decode_green_metadata(&h->green_metadata, &gbyte_payload);
break;
default:
ret = ff_h2645_sei_message_decode(&h->common, type, AV_CODEC_ID_H264,
&gb_payload, &gbyte_payload, logctx);
if (ret == FF_H2645_SEI_MESSAGE_UNHANDLED)
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));
}
bytestream2_skipu(&gbyte, size);
}
return master_ret;
}
const char *ff_h264_sei_stereo_mode(const H2645SEIFramePacking *h)
{
if (h->arrangement_cancel_flag == 0) {
switch (h->arrangement_type) {
case SEI_FPA_H264_TYPE_CHECKERBOARD:
if (h->content_interpretation_type == 2)
return "checkerboard_rl";
else
return "checkerboard_lr";
case SEI_FPA_H264_TYPE_INTERLEAVE_COLUMN:
if (h->content_interpretation_type == 2)
return "col_interleaved_rl";
else
return "col_interleaved_lr";
case SEI_FPA_H264_TYPE_INTERLEAVE_ROW:
if (h->content_interpretation_type == 2)
return "row_interleaved_rl";
else
return "row_interleaved_lr";
case SEI_FPA_TYPE_SIDE_BY_SIDE:
if (h->content_interpretation_type == 2)
return "right_left";
else
return "left_right";
case SEI_FPA_TYPE_TOP_BOTTOM:
if (h->content_interpretation_type == 2)
return "bottom_top";
else
return "top_bottom";
case SEI_FPA_TYPE_INTERLEAVE_TEMPORAL:
if (h->content_interpretation_type == 2)
return "block_rl";
else
return "block_lr";
case SEI_FPA_H264_TYPE_2D:
default:
return "mono";
}
} else if (h->arrangement_cancel_flag == 1) {
return "mono";
} else {
return NULL;
}
}