ffmpeg/libavcodec/remove_extradata_bsf.c

254 lines
7.2 KiB
C

/*
* copyright (c) 2006 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
*/
#include "libavutil/log.h"
#include "libavutil/opt.h"
#include "av1_parse.h"
#include "bsf.h"
#include "bsf_internal.h"
#include "h264.h"
#include "hevc.h"
#include "startcode.h"
#include "vc1_common.h"
enum RemoveFreq {
REMOVE_FREQ_KEYFRAME,
REMOVE_FREQ_ALL,
REMOVE_FREQ_NONKEYFRAME,
};
#define START_CODE 0x000001
typedef struct RemoveExtradataContext {
const AVClass *class;
int freq;
} RemoveExtradataContext;
static int av1_split(const uint8_t *buf, int buf_size, void *logctx)
{
AV1OBU obu;
const uint8_t *ptr = buf, *end = buf + buf_size;
while (ptr < end) {
int len = ff_av1_extract_obu(&obu, ptr, buf_size, logctx);
if (len < 0)
break;
if (obu.type == AV1_OBU_FRAME_HEADER ||
obu.type == AV1_OBU_FRAME) {
return ptr - buf;
}
ptr += len;
buf_size -= len;
}
return 0;
}
static int h264_split(const uint8_t *buf, int buf_size)
{
const uint8_t *ptr = buf, *end = buf + buf_size;
uint32_t state = -1;
int has_sps = 0;
int has_pps = 0;
int nalu_type;
while (ptr < end) {
ptr = avpriv_find_start_code(ptr, end, &state);
if ((state & 0xFFFFFF00) != 0x100)
break;
nalu_type = state & 0x1F;
if (nalu_type == H264_NAL_SPS) {
has_sps = 1;
} else if (nalu_type == H264_NAL_PPS)
has_pps = 1;
/* else if (nalu_type == 0x01 ||
* nalu_type == 0x02 ||
* nalu_type == 0x05) {
* }
*/
else if ((nalu_type != H264_NAL_SEI || has_pps) &&
nalu_type != H264_NAL_AUD && nalu_type != H264_NAL_SPS_EXT &&
nalu_type != 0x0f) {
if (has_sps) {
while (ptr - 4 > buf && ptr[-5] == 0)
ptr--;
return ptr - 4 - buf;
}
}
}
return 0;
}
// Split after the parameter sets at the beginning of the stream if they exist.
static int hevc_split(const uint8_t *buf, int buf_size)
{
const uint8_t *ptr = buf, *end = buf + buf_size;
uint32_t state = -1;
int has_vps = 0;
int has_sps = 0;
int has_pps = 0;
int nut;
while (ptr < end) {
ptr = avpriv_find_start_code(ptr, end, &state);
if ((state >> 8) != START_CODE)
break;
nut = (state >> 1) & 0x3F;
if (nut == HEVC_NAL_VPS)
has_vps = 1;
else if (nut == HEVC_NAL_SPS)
has_sps = 1;
else if (nut == HEVC_NAL_PPS)
has_pps = 1;
else if ((nut != HEVC_NAL_SEI_PREFIX || has_pps) &&
nut != HEVC_NAL_AUD) {
if (has_vps && has_sps) {
while (ptr - 4 > buf && ptr[-5] == 0)
ptr--;
return ptr - 4 - buf;
}
}
}
return 0;
}
static int mpegvideo_split(const uint8_t *buf, int buf_size)
{
uint32_t state = -1;
int found = 0;
for (int i = 0; i < buf_size; i++) {
state = (state << 8) | buf[i];
if (state == 0x1B3) {
found = 1;
} else if (found && state != 0x1B5 && state < 0x200 && state >= 0x100)
return i - 3;
}
return 0;
}
static int mpeg4video_split(const uint8_t *buf, int buf_size)
{
const uint8_t *ptr = buf, *end = buf + buf_size;
uint32_t state = -1;
while (ptr < end) {
ptr = avpriv_find_start_code(ptr, end, &state);
if (state == 0x1B3 || state == 0x1B6)
return ptr - 4 - buf;
}
return 0;
}
static int vc1_split(const uint8_t *buf, int buf_size)
{
const uint8_t *ptr = buf, *end = buf + buf_size;
uint32_t state = -1;
int charged = 0;
while (ptr < end) {
ptr = avpriv_find_start_code(ptr, end, &state);
if (state == VC1_CODE_SEQHDR || state == VC1_CODE_ENTRYPOINT) {
charged = 1;
} else if (charged && IS_MARKER(state))
return ptr - 4 - buf;
}
return 0;
}
static int remove_extradata(AVBSFContext *ctx, AVPacket *pkt)
{
RemoveExtradataContext *s = ctx->priv_data;
int ret;
ret = ff_bsf_get_packet_ref(ctx, pkt);
if (ret < 0)
return ret;
if (s->freq == REMOVE_FREQ_ALL ||
(s->freq == REMOVE_FREQ_NONKEYFRAME && !(pkt->flags & AV_PKT_FLAG_KEY)) ||
(s->freq == REMOVE_FREQ_KEYFRAME && pkt->flags & AV_PKT_FLAG_KEY)) {
int i;
switch (ctx->par_in->codec_id) {
case AV_CODEC_ID_AV1:
i = av1_split(pkt->data, pkt->size, ctx);
break;
case AV_CODEC_ID_AVS2:
case AV_CODEC_ID_AVS3:
case AV_CODEC_ID_CAVS:
case AV_CODEC_ID_MPEG4:
i = mpeg4video_split(pkt->data, pkt->size);
break;
case AV_CODEC_ID_H264:
i = h264_split(pkt->data, pkt->size);
break;
case AV_CODEC_ID_HEVC:
i = hevc_split(pkt->data, pkt->size);
break;
case AV_CODEC_ID_MPEG1VIDEO:
case AV_CODEC_ID_MPEG2VIDEO:
i = mpegvideo_split(pkt->data, pkt->size);
break;
case AV_CODEC_ID_VC1:
i = vc1_split(pkt->data, pkt->size);
break;
default:
i = 0;
}
pkt->data += i;
pkt->size -= i;
}
return 0;
}
#define OFFSET(x) offsetof(RemoveExtradataContext, x)
#define FLAGS (AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_BSF_PARAM)
static const AVOption options[] = {
{ "freq", NULL, OFFSET(freq), AV_OPT_TYPE_INT, { .i64 = REMOVE_FREQ_KEYFRAME }, REMOVE_FREQ_KEYFRAME, REMOVE_FREQ_NONKEYFRAME, FLAGS, "freq" },
{ "k", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = REMOVE_FREQ_NONKEYFRAME }, .flags = FLAGS, .unit = "freq" },
{ "keyframe", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = REMOVE_FREQ_KEYFRAME }, .flags = FLAGS, .unit = "freq" },
{ "e", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = REMOVE_FREQ_ALL }, .flags = FLAGS, .unit = "freq" },
{ "all", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = REMOVE_FREQ_ALL }, .flags = FLAGS, .unit = "freq" },
{ NULL },
};
static const AVClass remove_extradata_class = {
.class_name = "remove_extradata",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
const FFBitStreamFilter ff_remove_extradata_bsf = {
.p.name = "remove_extra",
.p.priv_class = &remove_extradata_class,
.priv_data_size = sizeof(RemoveExtradataContext),
.filter = remove_extradata,
};