[FFmpeg-devel] [PATCH 11/20] lavc: Add mpeg2_metadata bitstream filter
Mark Thompson
sw at jkqxz.net
Wed Sep 13 02:44:01 EEST 2017
(cherry picked from commit b78c30d7ec26af67c00ce2002709a189f6a87a7e)
---
configure | 1 +
doc/bitstream_filters.texi | 36 ++++
libavcodec/Makefile | 1 +
libavcodec/bitstream_filters.c | 1 +
libavcodec/mpeg2_metadata_bsf.c | 360 ++++++++++++++++++++++++++++++++++++++++
5 files changed, 399 insertions(+)
create mode 100644 libavcodec/mpeg2_metadata_bsf.c
diff --git a/configure b/configure
index 96d6274d8a..da72148279 100755
--- a/configure
+++ b/configure
@@ -2855,6 +2855,7 @@ 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
diff --git a/doc/bitstream_filters.texi b/doc/bitstream_filters.texi
index 71c307f2e2..8a8756bdcc 100644
--- a/doc/bitstream_filters.texi
+++ b/doc/bitstream_filters.texi
@@ -324,6 +324,42 @@ See also the @ref{text2movsub} filter.
Decompress non-standard compressed MP3 audio headers.
+ at section mpeg2_metadata
+
+Modify metadata embedded in an MPEG-2 stream.
+
+ at table @option
+ at item display_aspect_ratio
+Set the display aspect ratio in the stream.
+
+The following fixed values are supported:
+ at table @option
+ at item 4/3
+ at item 16/9
+ at item 221/100
+ at end table
+Any other value will result in square pixels being signalled instead
+(see H.262 section 6.3.3 and table 6-3).
+
+ at 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).
+
+ at item video_format
+Set the video format in the stream (see H.262 section 6.3.6 and
+table 6-6).
+
+ at item colour_primaries
+ at item transfer_characteristics
+ at 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).
+
+ at end table
+
@section mpeg4_unpack_bframes
Unpack DivX-style packed B-frames.
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 76ba2acafb..948c7ec21f 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -1006,6 +1006,7 @@ OBJS-$(CONFIG_MPEG4_UNPACK_BFRAMES_BSF) += mpeg4_unpack_bframes_bsf.o
OBJS-$(CONFIG_MOV2TEXTSUB_BSF) += movsub_bsf.o
OBJS-$(CONFIG_MP3_HEADER_DECOMPRESS_BSF) += mp3_header_decompress_bsf.o \
mpegaudiodata.o
+OBJS-$(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
diff --git a/libavcodec/bitstream_filters.c b/libavcodec/bitstream_filters.c
index 6e6b894e7f..7b0cb5032a 100644
--- a/libavcodec/bitstream_filters.c
+++ b/libavcodec/bitstream_filters.c
@@ -38,6 +38,7 @@ 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_mp3_header_decompress_bsf;
+extern const AVBitStreamFilter ff_mpeg2_metadata_bsf;
extern const AVBitStreamFilter ff_mpeg4_unpack_bframes_bsf;
extern const AVBitStreamFilter ff_mov2textsub_bsf;
extern const AVBitStreamFilter ff_noise_bsf;
diff --git a/libavcodec/mpeg2_metadata_bsf.c b/libavcodec/mpeg2_metadata_bsf.c
new file mode 100644
index 0000000000..9da8fd128d
--- /dev/null
+++ b/libavcodec/mpeg2_metadata_bsf.c
@@ -0,0 +1,360 @@
+/*
+ * 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/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,
+ { .dbl = 0.0 }, 0, 65535 },
+
+ { "frame_rate", "Set frame rate",
+ OFFSET(frame_rate), AV_OPT_TYPE_RATIONAL,
+ { .dbl = 0.0 }, 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,
+};
--
2.11.0
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