lavc: Add mpeg2_metadata bitstream filter

This commit is contained in:
Mark Thompson 2017-08-01 15:35:14 +01:00
parent 2bc9ba8d3c
commit b78c30d7ec
5 changed files with 399 additions and 0 deletions

1
configure vendored
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@ -2329,6 +2329,7 @@ h264_metadata_bsf_select="cbs_h264"
h264_redundant_pps_bsf_select="cbs_h264"
hevc_metadata_bsf_select="cbs_h265"
mjpeg2jpeg_bsf_select="jpegtables"
mpeg2_metadata_bsf_select="cbs_mpeg2"
trace_headers_bsf_select="cbs_h264 cbs_h265 cbs_mpeg2"
# external libraries

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@ -210,6 +210,42 @@ avconv -i frame_%d.jpg -c:v copy rotated.avi
@section movsub
@section mpeg2_metadata
Modify metadata embedded in an MPEG-2 stream.
@table @option
@item display_aspect_ratio
Set the display aspect ratio in the stream.
The following fixed values are supported:
@table @option
@item 4/3
@item 16/9
@item 221/100
@end table
Any other value will result in square pixels being signalled instead
(see H.262 section 6.3.3 and table 6-3).
@item frame_rate
Set the frame rate in the stream. This is constructed from a table
of known values combined with a small multiplier and divisor - if
the supplied value is not exactly representable, the nearest
representable value will be used instead (see H.262 section 6.3.3
and table 6-4).
@item video_format
Set the video format in the stream (see H.262 section 6.3.6 and
table 6-6).
@item colour_primaries
@item transfer_characteristics
@item matrix_coefficients
Set the colour description in the stream (see H.262 section 6.3.6
and tables 6-7, 6-8 and 6-9).
@end table
@section mp3_header_compress
@section mp3_header_decompress

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@ -786,6 +786,7 @@ OBJS-$(CONFIG_IMX_DUMP_HEADER_BSF) += imx_dump_header_bsf.o
OBJS-$(CONFIG_MJPEG2JPEG_BSF) += mjpeg2jpeg_bsf.o
OBJS-$(CONFIG_MJPEGA_DUMP_HEADER_BSF) += mjpega_dump_header_bsf.o
OBJS-$(CONFIG_MOV2TEXTSUB_BSF) += movsub_bsf.o
OBJS-$(CONFIG_MPEG2_METADATA_BSF) += mpeg2_metadata_bsf.o
OBJS-$(CONFIG_NOISE_BSF) += noise_bsf.o
OBJS-$(CONFIG_NULL_BSF) += null_bsf.o
OBJS-$(CONFIG_REMOVE_EXTRADATA_BSF) += remove_extradata_bsf.o

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@ -37,6 +37,7 @@ extern const AVBitStreamFilter ff_imx_dump_header_bsf;
extern const AVBitStreamFilter ff_mjpeg2jpeg_bsf;
extern const AVBitStreamFilter ff_mjpega_dump_header_bsf;
extern const AVBitStreamFilter ff_mov2textsub_bsf;
extern const AVBitStreamFilter ff_mpeg2_metadata_bsf;
extern const AVBitStreamFilter ff_null_bsf;
extern const AVBitStreamFilter ff_text2movsub_bsf;
extern const AVBitStreamFilter ff_noise_bsf;

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@ -0,0 +1,360 @@
/*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/avstring.h"
#include "libavutil/common.h"
#include "libavutil/opt.h"
#include "bsf.h"
#include "cbs.h"
#include "cbs_mpeg2.h"
typedef struct MPEG2MetadataContext {
const AVClass *class;
CodedBitstreamContext cbc;
CodedBitstreamFragment fragment;
MPEG2RawExtensionData sequence_display_extension;
AVRational display_aspect_ratio;
AVRational frame_rate;
int video_format;
int colour_primaries;
int transfer_characteristics;
int matrix_coefficients;
int mpeg1_warned;
} MPEG2MetadataContext;
static int mpeg2_metadata_update_fragment(AVBSFContext *bsf,
CodedBitstreamFragment *frag)
{
MPEG2MetadataContext *ctx = bsf->priv_data;
MPEG2RawSequenceHeader *sh = NULL;
MPEG2RawSequenceExtension *se = NULL;
MPEG2RawSequenceDisplayExtension *sde = NULL;
int i, se_pos, add_sde = 0;
for (i = 0; i < frag->nb_units; i++) {
if (frag->units[i].type == MPEG2_START_SEQUENCE_HEADER) {
sh = frag->units[i].content;
} else if (frag->units[i].type == MPEG2_START_EXTENSION) {
MPEG2RawExtensionData *ext = frag->units[i].content;
if (ext->extension_start_code_identifier ==
MPEG2_EXTENSION_SEQUENCE) {
se = &ext->data.sequence;
se_pos = i;
} else if (ext->extension_start_code_identifier ==
MPEG2_EXTENSION_SEQUENCE_DISPLAY) {
sde = &ext->data.sequence_display;
}
}
}
if (!sh || !se) {
// No sequence header and sequence extension: not an MPEG-2 video
// sequence.
if (sh && !ctx->mpeg1_warned) {
av_log(bsf, AV_LOG_WARNING, "Stream contains a sequence "
"header but not a sequence extension: maybe it's "
"actually MPEG-1?\n");
ctx->mpeg1_warned = 1;
}
return 0;
}
if (ctx->display_aspect_ratio.num && ctx->display_aspect_ratio.den) {
int num, den;
av_reduce(&num, &den, ctx->display_aspect_ratio.num,
ctx->display_aspect_ratio.den, 65535);
if (num == 4 && den == 3)
sh->aspect_ratio_information = 2;
else if (num == 16 && den == 9)
sh->aspect_ratio_information = 3;
else if (num == 221 && den == 100)
sh->aspect_ratio_information = 4;
else
sh->aspect_ratio_information = 1;
}
if (ctx->frame_rate.num && ctx->frame_rate.den) {
// Table 6-4.
static AVRational frame_rate_table[] = {
{ 0, 0 },
{ 24000, 1001 },
{ 24, 1 },
{ 25, 1 },
{ 30000, 1001 },
{ 30, 1 },
{ 50, 1 },
{ 60000, 1001 },
{ 60, 1 },
};
int code, ext_n, ext_d;
AVRational best_error = { INT_MAX, 1 };
for (i = 1; i < FF_ARRAY_ELEMS(frame_rate_table); i++) {
if (av_cmp_q(ctx->frame_rate, frame_rate_table[i]) == 0) {
code = i;
ext_n = 1;
ext_d = 1;
goto found_frame_rate;
}
}
for (i = 1; i < FF_ARRAY_ELEMS(frame_rate_table); i++) {
AVRational fr, error;
int n, d, cmp;
for (n = 1; n <= 4; n++) {
for (d = 1; d <= 32; d++) {
fr = av_mul_q(frame_rate_table[i],
(AVRational) { n, d });
cmp = av_cmp_q(fr, ctx->frame_rate);
if (cmp == 0) {
code = i;
ext_n = n;
ext_d = d;
goto found_frame_rate;
}
if (cmp < 0)
error = av_div_q(ctx->frame_rate, fr);
else
error = av_div_q(fr, ctx->frame_rate);
cmp = av_cmp_q(error, best_error);
if (cmp < 0 || (cmp == 0 && n == 1 && d == 1)) {
code = i;
ext_n = n;
ext_d = d;
best_error = error;
}
}
}
}
found_frame_rate:
sh->frame_rate_code = code;
se->frame_rate_extension_n = ext_n - 1;
se->frame_rate_extension_d = ext_d - 1;
}
if (ctx->video_format >= 0 ||
ctx->colour_primaries >= 0 ||
ctx->transfer_characteristics >= 0 ||
ctx->matrix_coefficients >= 0) {
if (!sde) {
add_sde = 1;
ctx->sequence_display_extension.extension_start_code =
MPEG2_START_EXTENSION;
ctx->sequence_display_extension.extension_start_code_identifier =
MPEG2_EXTENSION_SEQUENCE_DISPLAY;
sde = &ctx->sequence_display_extension.data.sequence_display;
*sde = (MPEG2RawSequenceDisplayExtension) {
.video_format = 5,
.colour_description = 0,
.colour_primaries = 2,
.transfer_characteristics = 2,
.matrix_coefficients = 2,
.display_horizontal_size =
se->horizontal_size_extension << 12 | sh->horizontal_size_value,
.display_vertical_size =
se->vertical_size_extension << 12 | sh->vertical_size_value,
};
}
if (ctx->video_format >= 0)
sde->video_format = ctx->video_format;
if (ctx->colour_primaries >= 0 ||
ctx->transfer_characteristics >= 0 ||
ctx->matrix_coefficients >= 0) {
sde->colour_description = 1;
if (ctx->colour_primaries >= 0)
sde->colour_primaries = ctx->colour_primaries;
else if (add_sde)
sde->colour_primaries = 2;
if (ctx->transfer_characteristics >= 0)
sde->transfer_characteristics = ctx->transfer_characteristics;
else if (add_sde)
sde->transfer_characteristics = 2;
if (ctx->matrix_coefficients >= 0)
sde->matrix_coefficients = ctx->matrix_coefficients;
else if (add_sde)
sde->matrix_coefficients = 2;
}
}
if (add_sde) {
int err;
err = ff_cbs_insert_unit_content(&ctx->cbc, frag, se_pos + 1,
MPEG2_START_EXTENSION,
&ctx->sequence_display_extension);
if (err < 0) {
av_log(bsf, AV_LOG_ERROR, "Failed to insert new sequence "
"display extension.\n");
return err;
}
}
return 0;
}
static int mpeg2_metadata_filter(AVBSFContext *bsf, AVPacket *out)
{
MPEG2MetadataContext *ctx = bsf->priv_data;
AVPacket *in = NULL;
CodedBitstreamFragment *frag = &ctx->fragment;
int err;
err = ff_bsf_get_packet(bsf, &in);
if (err < 0)
goto fail;
err = ff_cbs_read_packet(&ctx->cbc, frag, in);
if (err < 0) {
av_log(bsf, AV_LOG_ERROR, "Failed to read packet.\n");
goto fail;
}
err = mpeg2_metadata_update_fragment(bsf, frag);
if (err < 0) {
av_log(bsf, AV_LOG_ERROR, "Failed to update frame fragment.\n");
goto fail;
}
err = ff_cbs_write_packet(&ctx->cbc, out, frag);
if (err < 0) {
av_log(bsf, AV_LOG_ERROR, "Failed to write packet.\n");
goto fail;
}
err = av_packet_copy_props(out, in);
if (err < 0) {
av_packet_unref(out);
goto fail;
}
err = 0;
fail:
ff_cbs_fragment_uninit(&ctx->cbc, frag);
av_packet_free(&in);
return err;
}
static int mpeg2_metadata_init(AVBSFContext *bsf)
{
MPEG2MetadataContext *ctx = bsf->priv_data;
CodedBitstreamFragment *frag = &ctx->fragment;
int err;
err = ff_cbs_init(&ctx->cbc, AV_CODEC_ID_MPEG2VIDEO, bsf);
if (err < 0)
return err;
if (bsf->par_in->extradata) {
err = ff_cbs_read_extradata(&ctx->cbc, frag, bsf->par_in);
if (err < 0) {
av_log(bsf, AV_LOG_ERROR, "Failed to read extradata.\n");
goto fail;
}
err = mpeg2_metadata_update_fragment(bsf, frag);
if (err < 0) {
av_log(bsf, AV_LOG_ERROR, "Failed to update metadata fragment.\n");
goto fail;
}
err = ff_cbs_write_extradata(&ctx->cbc, bsf->par_out, frag);
if (err < 0) {
av_log(bsf, AV_LOG_ERROR, "Failed to write extradata.\n");
goto fail;
}
}
err = 0;
fail:
ff_cbs_fragment_uninit(&ctx->cbc, frag);
return err;
}
static void mpeg2_metadata_close(AVBSFContext *bsf)
{
MPEG2MetadataContext *ctx = bsf->priv_data;
ff_cbs_close(&ctx->cbc);
}
#define OFFSET(x) offsetof(MPEG2MetadataContext, x)
static const AVOption mpeg2_metadata_options[] = {
{ "display_aspect_ratio", "Set display aspect ratio (table 6-3)",
OFFSET(display_aspect_ratio), AV_OPT_TYPE_RATIONAL,
{ .i64 = 0 }, 0, 65535 },
{ "frame_rate", "Set frame rate",
OFFSET(frame_rate), AV_OPT_TYPE_RATIONAL,
{ .i64 = 0 }, 0, UINT_MAX },
{ "video_format", "Set video format (table 6-6)",
OFFSET(video_format), AV_OPT_TYPE_INT,
{ .i64 = -1 }, -1, 7 },
{ "colour_primaries", "Set colour primaries (table 6-7)",
OFFSET(colour_primaries), AV_OPT_TYPE_INT,
{ .i64 = -1 }, -1, 255 },
{ "transfer_characteristics", "Set transfer characteristics (table 6-8)",
OFFSET(transfer_characteristics), AV_OPT_TYPE_INT,
{ .i64 = -1 }, -1, 255 },
{ "matrix_coefficients", "Set matrix coefficients (table 6-9)",
OFFSET(matrix_coefficients), AV_OPT_TYPE_INT,
{ .i64 = -1 }, -1, 255 },
{ NULL }
};
static const AVClass mpeg2_metadata_class = {
.class_name = "mpeg2_metadata_bsf",
.item_name = av_default_item_name,
.option = mpeg2_metadata_options,
.version = LIBAVCODEC_VERSION_MAJOR,
};
static const enum AVCodecID mpeg2_metadata_codec_ids[] = {
AV_CODEC_ID_MPEG2VIDEO, AV_CODEC_ID_NONE,
};
const AVBitStreamFilter ff_mpeg2_metadata_bsf = {
.name = "mpeg2_metadata",
.priv_data_size = sizeof(MPEG2MetadataContext),
.priv_class = &mpeg2_metadata_class,
.init = &mpeg2_metadata_init,
.close = &mpeg2_metadata_close,
.filter = &mpeg2_metadata_filter,
.codec_ids = mpeg2_metadata_codec_ids,
};