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FFmpeg/libavcodec/cbs_h2645.c
James Almer 3d51d3b42d avcodec/cbs_h265: add missing support for reserved_payload_extension_data SEI bits
Fixes ticket #8622

Reviewed-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Reviewed-by: Mark Thompson <sw@jkqxz.net>
Signed-off-by: James Almer <jamrial@gmail.com>
2020-05-03 19:53:01 -03:00

1624 lines
48 KiB
C

/*
* 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
*/
#include "libavutil/attributes.h"
#include "libavutil/avassert.h"
#include "bytestream.h"
#include "cbs.h"
#include "cbs_internal.h"
#include "cbs_h264.h"
#include "cbs_h265.h"
#include "h264.h"
#include "h264_sei.h"
#include "h2645_parse.h"
#include "hevc.h"
#include "hevc_sei.h"
static int cbs_read_ue_golomb(CodedBitstreamContext *ctx, GetBitContext *gbc,
const char *name, const int *subscripts,
uint32_t *write_to,
uint32_t range_min, uint32_t range_max)
{
uint32_t value;
int position, i, j;
unsigned int k;
char bits[65];
position = get_bits_count(gbc);
for (i = 0; i < 32; i++) {
if (get_bits_left(gbc) < i + 1) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid ue-golomb code at "
"%s: bitstream ended.\n", name);
return AVERROR_INVALIDDATA;
}
k = get_bits1(gbc);
bits[i] = k ? '1' : '0';
if (k)
break;
}
if (i >= 32) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid ue-golomb code at "
"%s: more than 31 zeroes.\n", name);
return AVERROR_INVALIDDATA;
}
value = 1;
for (j = 0; j < i; j++) {
k = get_bits1(gbc);
bits[i + j + 1] = k ? '1' : '0';
value = value << 1 | k;
}
bits[i + j + 1] = 0;
--value;
if (ctx->trace_enable)
ff_cbs_trace_syntax_element(ctx, position, name, subscripts,
bits, value);
if (value < range_min || value > range_max) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "%s out of range: "
"%"PRIu32", but must be in [%"PRIu32",%"PRIu32"].\n",
name, value, range_min, range_max);
return AVERROR_INVALIDDATA;
}
*write_to = value;
return 0;
}
static int cbs_read_se_golomb(CodedBitstreamContext *ctx, GetBitContext *gbc,
const char *name, const int *subscripts,
int32_t *write_to,
int32_t range_min, int32_t range_max)
{
int32_t value;
int position, i, j;
unsigned int k;
uint32_t v;
char bits[65];
position = get_bits_count(gbc);
for (i = 0; i < 32; i++) {
if (get_bits_left(gbc) < i + 1) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid se-golomb code at "
"%s: bitstream ended.\n", name);
return AVERROR_INVALIDDATA;
}
k = get_bits1(gbc);
bits[i] = k ? '1' : '0';
if (k)
break;
}
if (i >= 32) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid se-golomb code at "
"%s: more than 31 zeroes.\n", name);
return AVERROR_INVALIDDATA;
}
v = 1;
for (j = 0; j < i; j++) {
k = get_bits1(gbc);
bits[i + j + 1] = k ? '1' : '0';
v = v << 1 | k;
}
bits[i + j + 1] = 0;
if (v & 1)
value = -(int32_t)(v / 2);
else
value = v / 2;
if (ctx->trace_enable)
ff_cbs_trace_syntax_element(ctx, position, name, subscripts,
bits, value);
if (value < range_min || value > range_max) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "%s out of range: "
"%"PRId32", but must be in [%"PRId32",%"PRId32"].\n",
name, value, range_min, range_max);
return AVERROR_INVALIDDATA;
}
*write_to = value;
return 0;
}
static int cbs_write_ue_golomb(CodedBitstreamContext *ctx, PutBitContext *pbc,
const char *name, const int *subscripts,
uint32_t value,
uint32_t range_min, uint32_t range_max)
{
int len;
if (value < range_min || value > range_max) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "%s out of range: "
"%"PRIu32", but must be in [%"PRIu32",%"PRIu32"].\n",
name, value, range_min, range_max);
return AVERROR_INVALIDDATA;
}
av_assert0(value != UINT32_MAX);
len = av_log2(value + 1);
if (put_bits_left(pbc) < 2 * len + 1)
return AVERROR(ENOSPC);
if (ctx->trace_enable) {
char bits[65];
int i;
for (i = 0; i < len; i++)
bits[i] = '0';
bits[len] = '1';
for (i = 0; i < len; i++)
bits[len + i + 1] = (value + 1) >> (len - i - 1) & 1 ? '1' : '0';
bits[len + len + 1] = 0;
ff_cbs_trace_syntax_element(ctx, put_bits_count(pbc),
name, subscripts, bits, value);
}
put_bits(pbc, len, 0);
if (len + 1 < 32)
put_bits(pbc, len + 1, value + 1);
else
put_bits32(pbc, value + 1);
return 0;
}
static int cbs_write_se_golomb(CodedBitstreamContext *ctx, PutBitContext *pbc,
const char *name, const int *subscripts,
int32_t value,
int32_t range_min, int32_t range_max)
{
int len;
uint32_t uvalue;
if (value < range_min || value > range_max) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "%s out of range: "
"%"PRId32", but must be in [%"PRId32",%"PRId32"].\n",
name, value, range_min, range_max);
return AVERROR_INVALIDDATA;
}
av_assert0(value != INT32_MIN);
if (value == 0)
uvalue = 0;
else if (value > 0)
uvalue = 2 * (uint32_t)value - 1;
else
uvalue = 2 * (uint32_t)-value;
len = av_log2(uvalue + 1);
if (put_bits_left(pbc) < 2 * len + 1)
return AVERROR(ENOSPC);
if (ctx->trace_enable) {
char bits[65];
int i;
for (i = 0; i < len; i++)
bits[i] = '0';
bits[len] = '1';
for (i = 0; i < len; i++)
bits[len + i + 1] = (uvalue + 1) >> (len - i - 1) & 1 ? '1' : '0';
bits[len + len + 1] = 0;
ff_cbs_trace_syntax_element(ctx, put_bits_count(pbc),
name, subscripts, bits, value);
}
put_bits(pbc, len, 0);
if (len + 1 < 32)
put_bits(pbc, len + 1, uvalue + 1);
else
put_bits32(pbc, uvalue + 1);
return 0;
}
// payload_extension_present() - true if we are before the last 1-bit
// in the payload structure, which must be in the last byte.
static int cbs_h265_payload_extension_present(GetBitContext *gbc, uint32_t payload_size,
int cur_pos)
{
int bits_left = payload_size * 8 - cur_pos;
return (bits_left > 0 &&
(bits_left > 7 || show_bits(gbc, bits_left) & MAX_UINT_BITS(bits_left - 1)));
}
#define HEADER(name) do { \
ff_cbs_trace_header(ctx, name); \
} while (0)
#define CHECK(call) do { \
err = (call); \
if (err < 0) \
return err; \
} while (0)
#define FUNC_NAME(rw, codec, name) cbs_ ## codec ## _ ## rw ## _ ## name
#define FUNC_H264(rw, name) FUNC_NAME(rw, h264, name)
#define FUNC_H265(rw, name) FUNC_NAME(rw, h265, name)
#define SUBSCRIPTS(subs, ...) (subs > 0 ? ((int[subs + 1]){ subs, __VA_ARGS__ }) : NULL)
#define u(width, name, range_min, range_max) \
xu(width, name, current->name, range_min, range_max, 0, )
#define ub(width, name) \
xu(width, name, current->name, 0, MAX_UINT_BITS(width), 0, )
#define flag(name) ub(1, name)
#define ue(name, range_min, range_max) \
xue(name, current->name, range_min, range_max, 0, )
#define i(width, name, range_min, range_max) \
xi(width, name, current->name, range_min, range_max, 0, )
#define ib(width, name) \
xi(width, name, current->name, MIN_INT_BITS(width), MAX_INT_BITS(width), 0, )
#define se(name, range_min, range_max) \
xse(name, current->name, range_min, range_max, 0, )
#define us(width, name, range_min, range_max, subs, ...) \
xu(width, name, current->name, range_min, range_max, subs, __VA_ARGS__)
#define ubs(width, name, subs, ...) \
xu(width, name, current->name, 0, MAX_UINT_BITS(width), subs, __VA_ARGS__)
#define flags(name, subs, ...) \
xu(1, name, current->name, 0, 1, subs, __VA_ARGS__)
#define ues(name, range_min, range_max, subs, ...) \
xue(name, current->name, range_min, range_max, subs, __VA_ARGS__)
#define is(width, name, range_min, range_max, subs, ...) \
xi(width, name, current->name, range_min, range_max, subs, __VA_ARGS__)
#define ibs(width, name, subs, ...) \
xi(width, name, current->name, MIN_INT_BITS(width), MAX_INT_BITS(width), subs, __VA_ARGS__)
#define ses(name, range_min, range_max, subs, ...) \
xse(name, current->name, range_min, range_max, subs, __VA_ARGS__)
#define fixed(width, name, value) do { \
av_unused uint32_t fixed_value = value; \
xu(width, name, fixed_value, value, value, 0, ); \
} while (0)
#define READ
#define READWRITE read
#define RWContext GetBitContext
#define xu(width, name, var, range_min, range_max, subs, ...) do { \
uint32_t value; \
CHECK(ff_cbs_read_unsigned(ctx, rw, width, #name, \
SUBSCRIPTS(subs, __VA_ARGS__), \
&value, range_min, range_max)); \
var = value; \
} while (0)
#define xue(name, var, range_min, range_max, subs, ...) do { \
uint32_t value; \
CHECK(cbs_read_ue_golomb(ctx, rw, #name, \
SUBSCRIPTS(subs, __VA_ARGS__), \
&value, range_min, range_max)); \
var = value; \
} while (0)
#define xi(width, name, var, range_min, range_max, subs, ...) do { \
int32_t value; \
CHECK(ff_cbs_read_signed(ctx, rw, width, #name, \
SUBSCRIPTS(subs, __VA_ARGS__), \
&value, range_min, range_max)); \
var = value; \
} while (0)
#define xse(name, var, range_min, range_max, subs, ...) do { \
int32_t value; \
CHECK(cbs_read_se_golomb(ctx, rw, #name, \
SUBSCRIPTS(subs, __VA_ARGS__), \
&value, range_min, range_max)); \
var = value; \
} while (0)
#define infer(name, value) do { \
current->name = value; \
} while (0)
static int cbs_h2645_read_more_rbsp_data(GetBitContext *gbc)
{
int bits_left = get_bits_left(gbc);
if (bits_left > 8)
return 1;
if (bits_left == 0)
return 0;
if (show_bits(gbc, bits_left) & MAX_UINT_BITS(bits_left - 1))
return 1;
return 0;
}
#define more_rbsp_data(var) ((var) = cbs_h2645_read_more_rbsp_data(rw))
#define byte_alignment(rw) (get_bits_count(rw) % 8)
#define allocate(name, size) do { \
name ## _ref = av_buffer_allocz(size + \
AV_INPUT_BUFFER_PADDING_SIZE); \
if (!name ## _ref) \
return AVERROR(ENOMEM); \
name = name ## _ref->data; \
} while (0)
#define FUNC(name) FUNC_H264(READWRITE, name)
#include "cbs_h264_syntax_template.c"
#undef FUNC
#define FUNC(name) FUNC_H265(READWRITE, name)
#include "cbs_h265_syntax_template.c"
#undef FUNC
#undef READ
#undef READWRITE
#undef RWContext
#undef xu
#undef xi
#undef xue
#undef xse
#undef infer
#undef more_rbsp_data
#undef byte_alignment
#undef allocate
#define WRITE
#define READWRITE write
#define RWContext PutBitContext
#define xu(width, name, var, range_min, range_max, subs, ...) do { \
uint32_t value = var; \
CHECK(ff_cbs_write_unsigned(ctx, rw, width, #name, \
SUBSCRIPTS(subs, __VA_ARGS__), \
value, range_min, range_max)); \
} while (0)
#define xue(name, var, range_min, range_max, subs, ...) do { \
uint32_t value = var; \
CHECK(cbs_write_ue_golomb(ctx, rw, #name, \
SUBSCRIPTS(subs, __VA_ARGS__), \
value, range_min, range_max)); \
} while (0)
#define xi(width, name, var, range_min, range_max, subs, ...) do { \
int32_t value = var; \
CHECK(ff_cbs_write_signed(ctx, rw, width, #name, \
SUBSCRIPTS(subs, __VA_ARGS__), \
value, range_min, range_max)); \
} while (0)
#define xse(name, var, range_min, range_max, subs, ...) do { \
int32_t value = var; \
CHECK(cbs_write_se_golomb(ctx, rw, #name, \
SUBSCRIPTS(subs, __VA_ARGS__), \
value, range_min, range_max)); \
} while (0)
#define infer(name, value) do { \
if (current->name != (value)) { \
av_log(ctx->log_ctx, AV_LOG_WARNING, "Warning: " \
"%s does not match inferred value: " \
"%"PRId64", but should be %"PRId64".\n", \
#name, (int64_t)current->name, (int64_t)(value)); \
} \
} while (0)
#define more_rbsp_data(var) (var)
#define byte_alignment(rw) (put_bits_count(rw) % 8)
#define allocate(name, size) do { \
if (!name) { \
av_log(ctx->log_ctx, AV_LOG_ERROR, "%s must be set " \
"for writing.\n", #name); \
return AVERROR_INVALIDDATA; \
} \
} while (0)
#define FUNC(name) FUNC_H264(READWRITE, name)
#include "cbs_h264_syntax_template.c"
#undef FUNC
#define FUNC(name) FUNC_H265(READWRITE, name)
#include "cbs_h265_syntax_template.c"
#undef FUNC
#undef WRITE
#undef READWRITE
#undef RWContext
#undef xu
#undef xi
#undef xue
#undef xse
#undef u
#undef i
#undef flag
#undef ue
#undef se
#undef infer
#undef more_rbsp_data
#undef byte_alignment
#undef allocate
static void cbs_h264_free_pps(void *opaque, uint8_t *content)
{
H264RawPPS *pps = (H264RawPPS*)content;
av_buffer_unref(&pps->slice_group_id_ref);
av_freep(&content);
}
static void cbs_h264_free_sei_payload(H264RawSEIPayload *payload)
{
switch (payload->payload_type) {
case H264_SEI_TYPE_BUFFERING_PERIOD:
case H264_SEI_TYPE_PIC_TIMING:
case H264_SEI_TYPE_PAN_SCAN_RECT:
case H264_SEI_TYPE_RECOVERY_POINT:
case H264_SEI_TYPE_DISPLAY_ORIENTATION:
case H264_SEI_TYPE_MASTERING_DISPLAY_COLOUR_VOLUME:
case H264_SEI_TYPE_ALTERNATIVE_TRANSFER:
break;
case H264_SEI_TYPE_USER_DATA_REGISTERED:
av_buffer_unref(&payload->payload.user_data_registered.data_ref);
break;
case H264_SEI_TYPE_USER_DATA_UNREGISTERED:
av_buffer_unref(&payload->payload.user_data_unregistered.data_ref);
break;
default:
av_buffer_unref(&payload->payload.other.data_ref);
break;
}
}
static void cbs_h264_free_sei(void *opaque, uint8_t *content)
{
H264RawSEI *sei = (H264RawSEI*)content;
int i;
for (i = 0; i < sei->payload_count; i++)
cbs_h264_free_sei_payload(&sei->payload[i]);
av_freep(&content);
}
static void cbs_h264_free_slice(void *opaque, uint8_t *content)
{
H264RawSlice *slice = (H264RawSlice*)content;
av_buffer_unref(&slice->data_ref);
av_freep(&content);
}
static void cbs_h265_free_vps(void *opaque, uint8_t *content)
{
H265RawVPS *vps = (H265RawVPS*)content;
av_buffer_unref(&vps->extension_data.data_ref);
av_freep(&content);
}
static void cbs_h265_free_sps(void *opaque, uint8_t *content)
{
H265RawSPS *sps = (H265RawSPS*)content;
av_buffer_unref(&sps->extension_data.data_ref);
av_freep(&content);
}
static void cbs_h265_free_pps(void *opaque, uint8_t *content)
{
H265RawPPS *pps = (H265RawPPS*)content;
av_buffer_unref(&pps->extension_data.data_ref);
av_freep(&content);
}
static void cbs_h265_free_slice(void *opaque, uint8_t *content)
{
H265RawSlice *slice = (H265RawSlice*)content;
av_buffer_unref(&slice->data_ref);
av_freep(&content);
}
static void cbs_h265_free_sei_payload(H265RawSEIPayload *payload)
{
switch (payload->payload_type) {
case HEVC_SEI_TYPE_BUFFERING_PERIOD:
case HEVC_SEI_TYPE_PICTURE_TIMING:
case HEVC_SEI_TYPE_PAN_SCAN_RECT:
case HEVC_SEI_TYPE_RECOVERY_POINT:
case HEVC_SEI_TYPE_DISPLAY_ORIENTATION:
case HEVC_SEI_TYPE_ACTIVE_PARAMETER_SETS:
case HEVC_SEI_TYPE_DECODED_PICTURE_HASH:
case HEVC_SEI_TYPE_TIME_CODE:
case HEVC_SEI_TYPE_MASTERING_DISPLAY_INFO:
case HEVC_SEI_TYPE_CONTENT_LIGHT_LEVEL_INFO:
case HEVC_SEI_TYPE_ALTERNATIVE_TRANSFER_CHARACTERISTICS:
case HEVC_SEI_TYPE_ALPHA_CHANNEL_INFO:
break;
case HEVC_SEI_TYPE_USER_DATA_REGISTERED_ITU_T_T35:
av_buffer_unref(&payload->payload.user_data_registered.data_ref);
break;
case HEVC_SEI_TYPE_USER_DATA_UNREGISTERED:
av_buffer_unref(&payload->payload.user_data_unregistered.data_ref);
break;
default:
av_buffer_unref(&payload->payload.other.data_ref);
break;
}
av_buffer_unref(&payload->extension_data.data_ref);
}
static void cbs_h265_free_sei(void *opaque, uint8_t *content)
{
H265RawSEI *sei = (H265RawSEI*)content;
int i;
for (i = 0; i < sei->payload_count; i++)
cbs_h265_free_sei_payload(&sei->payload[i]);
av_freep(&content);
}
static int cbs_h2645_fragment_add_nals(CodedBitstreamContext *ctx,
CodedBitstreamFragment *frag,
const H2645Packet *packet)
{
int err, i;
for (i = 0; i < packet->nb_nals; i++) {
const H2645NAL *nal = &packet->nals[i];
AVBufferRef *ref;
size_t size = nal->size;
if (nal->nuh_layer_id > 0)
continue;
// Remove trailing zeroes.
while (size > 0 && nal->data[size - 1] == 0)
--size;
if (size == 0) {
av_log(ctx->log_ctx, AV_LOG_VERBOSE, "Discarding empty 0 NAL unit\n");
continue;
}
ref = (nal->data == nal->raw_data) ? frag->data_ref
: packet->rbsp.rbsp_buffer_ref;
err = ff_cbs_insert_unit_data(ctx, frag, -1, nal->type,
(uint8_t*)nal->data, size, ref);
if (err < 0)
return err;
}
return 0;
}
static int cbs_h2645_split_fragment(CodedBitstreamContext *ctx,
CodedBitstreamFragment *frag,
int header)
{
enum AVCodecID codec_id = ctx->codec->codec_id;
CodedBitstreamH2645Context *priv = ctx->priv_data;
GetByteContext gbc;
int err;
av_assert0(frag->data && frag->nb_units == 0);
if (frag->data_size == 0)
return 0;
if (header && frag->data[0] && codec_id == AV_CODEC_ID_H264) {
// AVCC header.
size_t size, start, end;
int i, count, version;
priv->mp4 = 1;
bytestream2_init(&gbc, frag->data, frag->data_size);
if (bytestream2_get_bytes_left(&gbc) < 6)
return AVERROR_INVALIDDATA;
version = bytestream2_get_byte(&gbc);
if (version != 1) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid AVCC header: "
"first byte %u.\n", version);
return AVERROR_INVALIDDATA;
}
bytestream2_skip(&gbc, 3);
priv->nal_length_size = (bytestream2_get_byte(&gbc) & 3) + 1;
// SPS array.
count = bytestream2_get_byte(&gbc) & 0x1f;
start = bytestream2_tell(&gbc);
for (i = 0; i < count; i++) {
if (bytestream2_get_bytes_left(&gbc) < 2 * (count - i))
return AVERROR_INVALIDDATA;
size = bytestream2_get_be16(&gbc);
if (bytestream2_get_bytes_left(&gbc) < size)
return AVERROR_INVALIDDATA;
bytestream2_skip(&gbc, size);
}
end = bytestream2_tell(&gbc);
err = ff_h2645_packet_split(&priv->read_packet,
frag->data + start, end - start,
ctx->log_ctx, 1, 2, AV_CODEC_ID_H264, 1, 1);
if (err < 0) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "Failed to split AVCC SPS array.\n");
return err;
}
err = cbs_h2645_fragment_add_nals(ctx, frag, &priv->read_packet);
if (err < 0)
return err;
// PPS array.
count = bytestream2_get_byte(&gbc);
start = bytestream2_tell(&gbc);
for (i = 0; i < count; i++) {
if (bytestream2_get_bytes_left(&gbc) < 2 * (count - i))
return AVERROR_INVALIDDATA;
size = bytestream2_get_be16(&gbc);
if (bytestream2_get_bytes_left(&gbc) < size)
return AVERROR_INVALIDDATA;
bytestream2_skip(&gbc, size);
}
end = bytestream2_tell(&gbc);
err = ff_h2645_packet_split(&priv->read_packet,
frag->data + start, end - start,
ctx->log_ctx, 1, 2, AV_CODEC_ID_H264, 1, 1);
if (err < 0) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "Failed to split AVCC PPS array.\n");
return err;
}
err = cbs_h2645_fragment_add_nals(ctx, frag, &priv->read_packet);
if (err < 0)
return err;
if (bytestream2_get_bytes_left(&gbc) > 0) {
av_log(ctx->log_ctx, AV_LOG_WARNING, "%u bytes left at end of AVCC "
"header.\n", bytestream2_get_bytes_left(&gbc));
}
} else if (header && frag->data[0] && codec_id == AV_CODEC_ID_HEVC) {
// HVCC header.
size_t size, start, end;
int i, j, nb_arrays, nal_unit_type, nb_nals, version;
priv->mp4 = 1;
bytestream2_init(&gbc, frag->data, frag->data_size);
if (bytestream2_get_bytes_left(&gbc) < 23)
return AVERROR_INVALIDDATA;
version = bytestream2_get_byte(&gbc);
if (version != 1) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid HVCC header: "
"first byte %u.\n", version);
return AVERROR_INVALIDDATA;
}
bytestream2_skip(&gbc, 20);
priv->nal_length_size = (bytestream2_get_byte(&gbc) & 3) + 1;
nb_arrays = bytestream2_get_byte(&gbc);
for (i = 0; i < nb_arrays; i++) {
nal_unit_type = bytestream2_get_byte(&gbc) & 0x3f;
nb_nals = bytestream2_get_be16(&gbc);
start = bytestream2_tell(&gbc);
for (j = 0; j < nb_nals; j++) {
if (bytestream2_get_bytes_left(&gbc) < 2)
return AVERROR_INVALIDDATA;
size = bytestream2_get_be16(&gbc);
if (bytestream2_get_bytes_left(&gbc) < size)
return AVERROR_INVALIDDATA;
bytestream2_skip(&gbc, size);
}
end = bytestream2_tell(&gbc);
err = ff_h2645_packet_split(&priv->read_packet,
frag->data + start, end - start,
ctx->log_ctx, 1, 2, AV_CODEC_ID_HEVC, 1, 1);
if (err < 0) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "Failed to split "
"HVCC array %d (%d NAL units of type %d).\n",
i, nb_nals, nal_unit_type);
return err;
}
err = cbs_h2645_fragment_add_nals(ctx, frag, &priv->read_packet);
if (err < 0)
return err;
}
} else {
// Annex B, or later MP4 with already-known parameters.
err = ff_h2645_packet_split(&priv->read_packet,
frag->data, frag->data_size,
ctx->log_ctx,
priv->mp4, priv->nal_length_size,
codec_id, 1, 1);
if (err < 0)
return err;
err = cbs_h2645_fragment_add_nals(ctx, frag, &priv->read_packet);
if (err < 0)
return err;
}
return 0;
}
#define cbs_h2645_replace_ps(h26n, ps_name, ps_var, id_element) \
static int cbs_h26 ## h26n ## _replace_ ## ps_var(CodedBitstreamContext *ctx, \
CodedBitstreamUnit *unit) \
{ \
CodedBitstreamH26 ## h26n ## Context *priv = ctx->priv_data; \
H26 ## h26n ## Raw ## ps_name *ps_var = unit->content; \
unsigned int id = ps_var->id_element; \
if (id >= FF_ARRAY_ELEMS(priv->ps_var)) { \
av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid " #ps_name \
" id : %d.\n", id); \
return AVERROR_INVALIDDATA; \
} \
if (priv->ps_var[id] == priv->active_ ## ps_var) \
priv->active_ ## ps_var = NULL ; \
av_buffer_unref(&priv->ps_var ## _ref[id]); \
if (unit->content_ref) \
priv->ps_var ## _ref[id] = av_buffer_ref(unit->content_ref); \
else \
priv->ps_var ## _ref[id] = av_buffer_alloc(sizeof(*ps_var)); \
if (!priv->ps_var ## _ref[id]) \
return AVERROR(ENOMEM); \
priv->ps_var[id] = (H26 ## h26n ## Raw ## ps_name *)priv->ps_var ## _ref[id]->data; \
if (!unit->content_ref) \
memcpy(priv->ps_var[id], ps_var, sizeof(*ps_var)); \
return 0; \
}
cbs_h2645_replace_ps(4, SPS, sps, seq_parameter_set_id)
cbs_h2645_replace_ps(4, PPS, pps, pic_parameter_set_id)
cbs_h2645_replace_ps(5, VPS, vps, vps_video_parameter_set_id)
cbs_h2645_replace_ps(5, SPS, sps, sps_seq_parameter_set_id)
cbs_h2645_replace_ps(5, PPS, pps, pps_pic_parameter_set_id)
static int cbs_h264_read_nal_unit(CodedBitstreamContext *ctx,
CodedBitstreamUnit *unit)
{
GetBitContext gbc;
int err;
err = init_get_bits(&gbc, unit->data, 8 * unit->data_size);
if (err < 0)
return err;
switch (unit->type) {
case H264_NAL_SPS:
{
H264RawSPS *sps;
err = ff_cbs_alloc_unit_content(ctx, unit, sizeof(*sps), NULL);
if (err < 0)
return err;
sps = unit->content;
err = cbs_h264_read_sps(ctx, &gbc, sps);
if (err < 0)
return err;
err = cbs_h264_replace_sps(ctx, unit);
if (err < 0)
return err;
}
break;
case H264_NAL_SPS_EXT:
{
err = ff_cbs_alloc_unit_content(ctx, unit,
sizeof(H264RawSPSExtension),
NULL);
if (err < 0)
return err;
err = cbs_h264_read_sps_extension(ctx, &gbc, unit->content);
if (err < 0)
return err;
}
break;
case H264_NAL_PPS:
{
H264RawPPS *pps;
err = ff_cbs_alloc_unit_content(ctx, unit, sizeof(*pps),
&cbs_h264_free_pps);
if (err < 0)
return err;
pps = unit->content;
err = cbs_h264_read_pps(ctx, &gbc, pps);
if (err < 0)
return err;
err = cbs_h264_replace_pps(ctx, unit);
if (err < 0)
return err;
}
break;
case H264_NAL_SLICE:
case H264_NAL_IDR_SLICE:
case H264_NAL_AUXILIARY_SLICE:
{
H264RawSlice *slice;
int pos, len;
err = ff_cbs_alloc_unit_content(ctx, unit, sizeof(*slice),
&cbs_h264_free_slice);
if (err < 0)
return err;
slice = unit->content;
err = cbs_h264_read_slice_header(ctx, &gbc, &slice->header);
if (err < 0)
return err;
if (!cbs_h2645_read_more_rbsp_data(&gbc))
return AVERROR_INVALIDDATA;
pos = get_bits_count(&gbc);
len = unit->data_size;
slice->data_size = len - pos / 8;
slice->data_ref = av_buffer_ref(unit->data_ref);
if (!slice->data_ref)
return AVERROR(ENOMEM);
slice->data = unit->data + pos / 8;
slice->data_bit_start = pos % 8;
}
break;
case H264_NAL_AUD:
{
err = ff_cbs_alloc_unit_content(ctx, unit,
sizeof(H264RawAUD), NULL);
if (err < 0)
return err;
err = cbs_h264_read_aud(ctx, &gbc, unit->content);
if (err < 0)
return err;
}
break;
case H264_NAL_SEI:
{
err = ff_cbs_alloc_unit_content(ctx, unit, sizeof(H264RawSEI),
&cbs_h264_free_sei);
if (err < 0)
return err;
err = cbs_h264_read_sei(ctx, &gbc, unit->content);
if (err < 0)
return err;
}
break;
case H264_NAL_FILLER_DATA:
{
err = ff_cbs_alloc_unit_content(ctx, unit,
sizeof(H264RawFiller), NULL);
if (err < 0)
return err;
err = cbs_h264_read_filler(ctx, &gbc, unit->content);
if (err < 0)
return err;
}
break;
case H264_NAL_END_SEQUENCE:
case H264_NAL_END_STREAM:
{
err = ff_cbs_alloc_unit_content(ctx, unit,
sizeof(H264RawNALUnitHeader),
NULL);
if (err < 0)
return err;
err = (unit->type == H264_NAL_END_SEQUENCE ?
cbs_h264_read_end_of_sequence :
cbs_h264_read_end_of_stream)(ctx, &gbc, unit->content);
if (err < 0)
return err;
}
break;
default:
return AVERROR(ENOSYS);
}
return 0;
}
static int cbs_h265_read_nal_unit(CodedBitstreamContext *ctx,
CodedBitstreamUnit *unit)
{
GetBitContext gbc;
int err;
err = init_get_bits(&gbc, unit->data, 8 * unit->data_size);
if (err < 0)
return err;
switch (unit->type) {
case HEVC_NAL_VPS:
{
H265RawVPS *vps;
err = ff_cbs_alloc_unit_content(ctx, unit, sizeof(*vps),
&cbs_h265_free_vps);
if (err < 0)
return err;
vps = unit->content;
err = cbs_h265_read_vps(ctx, &gbc, vps);
if (err < 0)
return err;
err = cbs_h265_replace_vps(ctx, unit);
if (err < 0)
return err;
}
break;
case HEVC_NAL_SPS:
{
H265RawSPS *sps;
err = ff_cbs_alloc_unit_content(ctx, unit, sizeof(*sps),
&cbs_h265_free_sps);
if (err < 0)
return err;
sps = unit->content;
err = cbs_h265_read_sps(ctx, &gbc, sps);
if (err < 0)
return err;
err = cbs_h265_replace_sps(ctx, unit);
if (err < 0)
return err;
}
break;
case HEVC_NAL_PPS:
{
H265RawPPS *pps;
err = ff_cbs_alloc_unit_content(ctx, unit, sizeof(*pps),
&cbs_h265_free_pps);
if (err < 0)
return err;
pps = unit->content;
err = cbs_h265_read_pps(ctx, &gbc, pps);
if (err < 0)
return err;
err = cbs_h265_replace_pps(ctx, unit);
if (err < 0)
return err;
}
break;
case HEVC_NAL_TRAIL_N:
case HEVC_NAL_TRAIL_R:
case HEVC_NAL_TSA_N:
case HEVC_NAL_TSA_R:
case HEVC_NAL_STSA_N:
case HEVC_NAL_STSA_R:
case HEVC_NAL_RADL_N:
case HEVC_NAL_RADL_R:
case HEVC_NAL_RASL_N:
case HEVC_NAL_RASL_R:
case HEVC_NAL_BLA_W_LP:
case HEVC_NAL_BLA_W_RADL:
case HEVC_NAL_BLA_N_LP:
case HEVC_NAL_IDR_W_RADL:
case HEVC_NAL_IDR_N_LP:
case HEVC_NAL_CRA_NUT:
{
H265RawSlice *slice;
int pos, len;
err = ff_cbs_alloc_unit_content(ctx, unit, sizeof(*slice),
&cbs_h265_free_slice);
if (err < 0)
return err;
slice = unit->content;
err = cbs_h265_read_slice_segment_header(ctx, &gbc, &slice->header);
if (err < 0)
return err;
if (!cbs_h2645_read_more_rbsp_data(&gbc))
return AVERROR_INVALIDDATA;
pos = get_bits_count(&gbc);
len = unit->data_size;
slice->data_size = len - pos / 8;
slice->data_ref = av_buffer_ref(unit->data_ref);
if (!slice->data_ref)
return AVERROR(ENOMEM);
slice->data = unit->data + pos / 8;
slice->data_bit_start = pos % 8;
}
break;
case HEVC_NAL_AUD:
{
err = ff_cbs_alloc_unit_content(ctx, unit,
sizeof(H265RawAUD), NULL);
if (err < 0)
return err;
err = cbs_h265_read_aud(ctx, &gbc, unit->content);
if (err < 0)
return err;
}
break;
case HEVC_NAL_SEI_PREFIX:
case HEVC_NAL_SEI_SUFFIX:
{
err = ff_cbs_alloc_unit_content(ctx, unit, sizeof(H265RawSEI),
&cbs_h265_free_sei);
if (err < 0)
return err;
err = cbs_h265_read_sei(ctx, &gbc, unit->content,
unit->type == HEVC_NAL_SEI_PREFIX);
if (err < 0)
return err;
}
break;
default:
return AVERROR(ENOSYS);
}
return 0;
}
static int cbs_h2645_write_slice_data(CodedBitstreamContext *ctx,
PutBitContext *pbc, const uint8_t *data,
size_t data_size, int data_bit_start)
{
size_t rest = data_size - (data_bit_start + 7) / 8;
const uint8_t *pos = data + data_bit_start / 8;
av_assert0(data_bit_start >= 0 &&
data_size > data_bit_start / 8);
if (data_size * 8 + 8 > put_bits_left(pbc))
return AVERROR(ENOSPC);
if (!rest)
goto rbsp_stop_one_bit;
// First copy the remaining bits of the first byte
// The above check ensures that we do not accidentally
// copy beyond the rbsp_stop_one_bit.
if (data_bit_start % 8)
put_bits(pbc, 8 - data_bit_start % 8,
*pos++ & MAX_UINT_BITS(8 - data_bit_start % 8));
if (put_bits_count(pbc) % 8 == 0) {
// If the writer is aligned at this point,
// memcpy can be used to improve performance.
// This happens normally for CABAC.
flush_put_bits(pbc);
memcpy(put_bits_ptr(pbc), pos, rest);
skip_put_bytes(pbc, rest);
} else {
// If not, we have to copy manually.
// rbsp_stop_one_bit forces us to special-case
// the last byte.
uint8_t temp;
int i;
for (; rest > 4; rest -= 4, pos += 4)
put_bits32(pbc, AV_RB32(pos));
for (; rest > 1; rest--, pos++)
put_bits(pbc, 8, *pos);
rbsp_stop_one_bit:
temp = rest ? *pos : *pos & MAX_UINT_BITS(8 - data_bit_start % 8);
av_assert0(temp);
i = ff_ctz(*pos);
temp = temp >> i;
i = rest ? (8 - i) : (8 - i - data_bit_start % 8);
put_bits(pbc, i, temp);
if (put_bits_count(pbc) % 8)
put_bits(pbc, 8 - put_bits_count(pbc) % 8, 0);
}
return 0;
}
static int cbs_h264_write_nal_unit(CodedBitstreamContext *ctx,
CodedBitstreamUnit *unit,
PutBitContext *pbc)
{
int err;
switch (unit->type) {
case H264_NAL_SPS:
{
H264RawSPS *sps = unit->content;
err = cbs_h264_write_sps(ctx, pbc, sps);
if (err < 0)
return err;
err = cbs_h264_replace_sps(ctx, unit);
if (err < 0)
return err;
}
break;
case H264_NAL_SPS_EXT:
{
H264RawSPSExtension *sps_ext = unit->content;
err = cbs_h264_write_sps_extension(ctx, pbc, sps_ext);
if (err < 0)
return err;
}
break;
case H264_NAL_PPS:
{
H264RawPPS *pps = unit->content;
err = cbs_h264_write_pps(ctx, pbc, pps);
if (err < 0)
return err;
err = cbs_h264_replace_pps(ctx, unit);
if (err < 0)
return err;
}
break;
case H264_NAL_SLICE:
case H264_NAL_IDR_SLICE:
case H264_NAL_AUXILIARY_SLICE:
{
H264RawSlice *slice = unit->content;
err = cbs_h264_write_slice_header(ctx, pbc, &slice->header);
if (err < 0)
return err;
if (slice->data) {
err = cbs_h2645_write_slice_data(ctx, pbc, slice->data,
slice->data_size,
slice->data_bit_start);
if (err < 0)
return err;
} else {
// No slice data - that was just the header.
// (Bitstream may be unaligned!)
}
}
break;
case H264_NAL_AUD:
{
err = cbs_h264_write_aud(ctx, pbc, unit->content);
if (err < 0)
return err;
}
break;
case H264_NAL_SEI:
{
err = cbs_h264_write_sei(ctx, pbc, unit->content);
if (err < 0)
return err;
}
break;
case H264_NAL_FILLER_DATA:
{
err = cbs_h264_write_filler(ctx, pbc, unit->content);
if (err < 0)
return err;
}
break;
case H264_NAL_END_SEQUENCE:
{
err = cbs_h264_write_end_of_sequence(ctx, pbc, unit->content);
if (err < 0)
return err;
}
break;
case H264_NAL_END_STREAM:
{
err = cbs_h264_write_end_of_stream(ctx, pbc, unit->content);
if (err < 0)
return err;
}
break;
default:
av_log(ctx->log_ctx, AV_LOG_ERROR, "Write unimplemented for "
"NAL unit type %"PRIu32".\n", unit->type);
return AVERROR_PATCHWELCOME;
}
return 0;
}
static int cbs_h265_write_nal_unit(CodedBitstreamContext *ctx,
CodedBitstreamUnit *unit,
PutBitContext *pbc)
{
int err;
switch (unit->type) {
case HEVC_NAL_VPS:
{
H265RawVPS *vps = unit->content;
err = cbs_h265_write_vps(ctx, pbc, vps);
if (err < 0)
return err;
err = cbs_h265_replace_vps(ctx, unit);
if (err < 0)
return err;
}
break;
case HEVC_NAL_SPS:
{
H265RawSPS *sps = unit->content;
err = cbs_h265_write_sps(ctx, pbc, sps);
if (err < 0)
return err;
err = cbs_h265_replace_sps(ctx, unit);
if (err < 0)
return err;
}
break;
case HEVC_NAL_PPS:
{
H265RawPPS *pps = unit->content;
err = cbs_h265_write_pps(ctx, pbc, pps);
if (err < 0)
return err;
err = cbs_h265_replace_pps(ctx, unit);
if (err < 0)
return err;
}
break;
case HEVC_NAL_TRAIL_N:
case HEVC_NAL_TRAIL_R:
case HEVC_NAL_TSA_N:
case HEVC_NAL_TSA_R:
case HEVC_NAL_STSA_N:
case HEVC_NAL_STSA_R:
case HEVC_NAL_RADL_N:
case HEVC_NAL_RADL_R:
case HEVC_NAL_RASL_N:
case HEVC_NAL_RASL_R:
case HEVC_NAL_BLA_W_LP:
case HEVC_NAL_BLA_W_RADL:
case HEVC_NAL_BLA_N_LP:
case HEVC_NAL_IDR_W_RADL:
case HEVC_NAL_IDR_N_LP:
case HEVC_NAL_CRA_NUT:
{
H265RawSlice *slice = unit->content;
err = cbs_h265_write_slice_segment_header(ctx, pbc, &slice->header);
if (err < 0)
return err;
if (slice->data) {
err = cbs_h2645_write_slice_data(ctx, pbc, slice->data,
slice->data_size,
slice->data_bit_start);
if (err < 0)
return err;
} else {
// No slice data - that was just the header.
}
}
break;
case HEVC_NAL_AUD:
{
err = cbs_h265_write_aud(ctx, pbc, unit->content);
if (err < 0)
return err;
}
break;
case HEVC_NAL_SEI_PREFIX:
case HEVC_NAL_SEI_SUFFIX:
{
err = cbs_h265_write_sei(ctx, pbc, unit->content,
unit->type == HEVC_NAL_SEI_PREFIX);
if (err < 0)
return err;
}
break;
default:
av_log(ctx->log_ctx, AV_LOG_ERROR, "Write unimplemented for "
"NAL unit type %"PRIu32".\n", unit->type);
return AVERROR_PATCHWELCOME;
}
return 0;
}
static int cbs_h2645_assemble_fragment(CodedBitstreamContext *ctx,
CodedBitstreamFragment *frag)
{
uint8_t *data;
size_t max_size, dp, sp;
int err, i, zero_run;
for (i = 0; i < frag->nb_units; i++) {
// Data should already all have been written when we get here.
av_assert0(frag->units[i].data);
}
max_size = 0;
for (i = 0; i < frag->nb_units; i++) {
// Start code + content with worst-case emulation prevention.
max_size += 4 + frag->units[i].data_size * 3 / 2;
}
data = av_realloc(NULL, max_size + AV_INPUT_BUFFER_PADDING_SIZE);
if (!data)
return AVERROR(ENOMEM);
dp = 0;
for (i = 0; i < frag->nb_units; i++) {
CodedBitstreamUnit *unit = &frag->units[i];
if (unit->data_bit_padding > 0) {
if (i < frag->nb_units - 1)
av_log(ctx->log_ctx, AV_LOG_WARNING, "Probably invalid "
"unaligned padding on non-final NAL unit.\n");
else
frag->data_bit_padding = unit->data_bit_padding;
}
if ((ctx->codec->codec_id == AV_CODEC_ID_H264 &&
(unit->type == H264_NAL_SPS ||
unit->type == H264_NAL_PPS)) ||
(ctx->codec->codec_id == AV_CODEC_ID_HEVC &&
(unit->type == HEVC_NAL_VPS ||
unit->type == HEVC_NAL_SPS ||
unit->type == HEVC_NAL_PPS)) ||
i == 0 /* (Assume this is the start of an access unit.) */) {
// zero_byte
data[dp++] = 0;
}
// start_code_prefix_one_3bytes
data[dp++] = 0;
data[dp++] = 0;
data[dp++] = 1;
zero_run = 0;
for (sp = 0; sp < unit->data_size; sp++) {
if (zero_run < 2) {
if (unit->data[sp] == 0)
++zero_run;
else
zero_run = 0;
} else {
if ((unit->data[sp] & ~3) == 0) {
// emulation_prevention_three_byte
data[dp++] = 3;
}
zero_run = unit->data[sp] == 0;
}
data[dp++] = unit->data[sp];
}
}
av_assert0(dp <= max_size);
err = av_reallocp(&data, dp + AV_INPUT_BUFFER_PADDING_SIZE);
if (err)
return err;
memset(data + dp, 0, AV_INPUT_BUFFER_PADDING_SIZE);
frag->data_ref = av_buffer_create(data, dp + AV_INPUT_BUFFER_PADDING_SIZE,
NULL, NULL, 0);
if (!frag->data_ref) {
av_freep(&data);
return AVERROR(ENOMEM);
}
frag->data = data;
frag->data_size = dp;
return 0;
}
static void cbs_h264_close(CodedBitstreamContext *ctx)
{
CodedBitstreamH264Context *h264 = ctx->priv_data;
int i;
ff_h2645_packet_uninit(&h264->common.read_packet);
for (i = 0; i < FF_ARRAY_ELEMS(h264->sps); i++)
av_buffer_unref(&h264->sps_ref[i]);
for (i = 0; i < FF_ARRAY_ELEMS(h264->pps); i++)
av_buffer_unref(&h264->pps_ref[i]);
}
static void cbs_h265_close(CodedBitstreamContext *ctx)
{
CodedBitstreamH265Context *h265 = ctx->priv_data;
int i;
ff_h2645_packet_uninit(&h265->common.read_packet);
for (i = 0; i < FF_ARRAY_ELEMS(h265->vps); i++)
av_buffer_unref(&h265->vps_ref[i]);
for (i = 0; i < FF_ARRAY_ELEMS(h265->sps); i++)
av_buffer_unref(&h265->sps_ref[i]);
for (i = 0; i < FF_ARRAY_ELEMS(h265->pps); i++)
av_buffer_unref(&h265->pps_ref[i]);
}
const CodedBitstreamType ff_cbs_type_h264 = {
.codec_id = AV_CODEC_ID_H264,
.priv_data_size = sizeof(CodedBitstreamH264Context),
.split_fragment = &cbs_h2645_split_fragment,
.read_unit = &cbs_h264_read_nal_unit,
.write_unit = &cbs_h264_write_nal_unit,
.assemble_fragment = &cbs_h2645_assemble_fragment,
.close = &cbs_h264_close,
};
const CodedBitstreamType ff_cbs_type_h265 = {
.codec_id = AV_CODEC_ID_HEVC,
.priv_data_size = sizeof(CodedBitstreamH265Context),
.split_fragment = &cbs_h2645_split_fragment,
.read_unit = &cbs_h265_read_nal_unit,
.write_unit = &cbs_h265_write_nal_unit,
.assemble_fragment = &cbs_h2645_assemble_fragment,
.close = &cbs_h265_close,
};
int ff_cbs_h264_add_sei_message(CodedBitstreamContext *ctx,
CodedBitstreamFragment *au,
H264RawSEIPayload *payload)
{
H264RawSEI *sei = NULL;
int err, i;
// Find an existing SEI NAL unit to add to.
for (i = 0; i < au->nb_units; i++) {
if (au->units[i].type == H264_NAL_SEI) {
sei = au->units[i].content;
if (sei->payload_count < H264_MAX_SEI_PAYLOADS)
break;
sei = NULL;
}
}
if (!sei) {
// Need to make a new SEI NAL unit. Insert it before the first
// slice data NAL unit; if no slice data, add at the end.
AVBufferRef *sei_ref;
sei = av_mallocz(sizeof(*sei));
if (!sei) {
err = AVERROR(ENOMEM);
goto fail;
}
sei->nal_unit_header.nal_unit_type = H264_NAL_SEI;
sei->nal_unit_header.nal_ref_idc = 0;
sei_ref = av_buffer_create((uint8_t*)sei, sizeof(*sei),
&cbs_h264_free_sei, NULL, 0);
if (!sei_ref) {
av_freep(&sei);
err = AVERROR(ENOMEM);
goto fail;
}
for (i = 0; i < au->nb_units; i++) {
if (au->units[i].type == H264_NAL_SLICE ||
au->units[i].type == H264_NAL_IDR_SLICE)
break;
}
err = ff_cbs_insert_unit_content(ctx, au, i, H264_NAL_SEI,
sei, sei_ref);
av_buffer_unref(&sei_ref);
if (err < 0)
goto fail;
}
memcpy(&sei->payload[sei->payload_count], payload, sizeof(*payload));
++sei->payload_count;
return 0;
fail:
cbs_h264_free_sei_payload(payload);
return err;
}
void ff_cbs_h264_delete_sei_message(CodedBitstreamContext *ctx,
CodedBitstreamFragment *au,
CodedBitstreamUnit *nal,
int position)
{
H264RawSEI *sei = nal->content;
av_assert0(nal->type == H264_NAL_SEI);
av_assert0(position >= 0 && position < sei->payload_count);
if (position == 0 && sei->payload_count == 1) {
// Deleting NAL unit entirely.
int i;
for (i = 0; i < au->nb_units; i++) {
if (&au->units[i] == nal)
break;
}
ff_cbs_delete_unit(ctx, au, i);
} else {
cbs_h264_free_sei_payload(&sei->payload[position]);
--sei->payload_count;
memmove(sei->payload + position,
sei->payload + position + 1,
(sei->payload_count - position) * sizeof(*sei->payload));
}
}