[FFmpeg-devel,2/2] lavc: Add VP9 metadata bitstream filter

Can adjust the colour information.
---
And nothing else, so meh.  Still, offers a clean filter for testing VP9 CBS.

I think it should have some FATE tests along the same lines as H.26[45] and MPEG-2, running across a set of streams and making sure it reads and writes them back correctly.  Not clear what set of streams to use, though - should I just pick a random set of the conformance test vectors which look sensible, or is there some more obvious subset?


 configure                      |   1 +
 libavcodec/Makefile            |   1 +
 libavcodec/bitstream_filters.c |   1 +
 libavcodec/vp9_metadata_bsf.c  | 143 +++++++++++++++++++++++++++++++++++++++++
 4 files changed, 146 insertions(+)
 create mode 100644 libavcodec/vp9_metadata_bsf.c

On 4/2/2018 7:47 PM, Mark Thompson wrote:
> Can adjust the colour information.
> ---
> And nothing else, so meh.  Still, offers a clean filter for testing VP9 CBS.
> 
> I think it should have some FATE tests along the same lines as H.26[45] and MPEG-2, running across a set of streams and making sure it reads and writes them back correctly.  Not clear what set of streams to use, though - should I just pick a random set of the conformance test vectors which look sensible, or is there some more obvious subset?

Use the existing conformance test samples, especially for profiles 1 to
3 since there's one for each pixel format and bit depth.

> 
> 
>  configure                      |   1 +
>  libavcodec/Makefile            |   1 +
>  libavcodec/bitstream_filters.c |   1 +
>  libavcodec/vp9_metadata_bsf.c  | 143 +++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 146 insertions(+)
>  create mode 100644 libavcodec/vp9_metadata_bsf.c
> 
> diff --git a/configure b/configure
> index 890de64ab4..28970cbdf8 100755
> --- a/configure
> +++ b/configure
> @@ -2986,6 +2986,7 @@ hevc_metadata_bsf_select="cbs_h265"
>  mjpeg2jpeg_bsf_select="jpegtables"
>  mpeg2_metadata_bsf_select="cbs_mpeg2"
>  trace_headers_bsf_select="cbs"
> +vp9_metadata_bsf_select="cbs_vp9"
>  
>  # external libraries
>  aac_at_decoder_deps="audiotoolbox"
> diff --git a/libavcodec/Makefile b/libavcodec/Makefile
> index 6ee16d855b..1a172f5597 100644
> --- a/libavcodec/Makefile
> +++ b/libavcodec/Makefile
> @@ -1067,6 +1067,7 @@ OBJS-$(CONFIG_NULL_BSF)                   += null_bsf.o
>  OBJS-$(CONFIG_REMOVE_EXTRADATA_BSF)       += remove_extradata_bsf.o
>  OBJS-$(CONFIG_TEXT2MOVSUB_BSF)            += movsub_bsf.o
>  OBJS-$(CONFIG_TRACE_HEADERS_BSF)          += trace_headers_bsf.o
> +OBJS-$(CONFIG_VP9_METADATA_BSF)           += vp9_metadata_bsf.o
>  OBJS-$(CONFIG_VP9_RAW_REORDER_BSF)        += vp9_raw_reorder_bsf.o
>  OBJS-$(CONFIG_VP9_SUPERFRAME_BSF)         += vp9_superframe_bsf.o
>  OBJS-$(CONFIG_VP9_SUPERFRAME_SPLIT_BSF)   += vp9_superframe_split_bsf.o
> diff --git a/libavcodec/bitstream_filters.c b/libavcodec/bitstream_filters.c
> index 18b698a85f..c21373621c 100644
> --- a/libavcodec/bitstream_filters.c
> +++ b/libavcodec/bitstream_filters.c
> @@ -49,6 +49,7 @@ extern const AVBitStreamFilter ff_null_bsf;
>  extern const AVBitStreamFilter ff_remove_extradata_bsf;
>  extern const AVBitStreamFilter ff_text2movsub_bsf;
>  extern const AVBitStreamFilter ff_trace_headers_bsf;
> +extern const AVBitStreamFilter ff_vp9_metadata_bsf;
>  extern const AVBitStreamFilter ff_vp9_raw_reorder_bsf;
>  extern const AVBitStreamFilter ff_vp9_superframe_bsf;
>  extern const AVBitStreamFilter ff_vp9_superframe_split_bsf;
> diff --git a/libavcodec/vp9_metadata_bsf.c b/libavcodec/vp9_metadata_bsf.c
> new file mode 100644
> index 0000000000..39994611a0
> --- /dev/null
> +++ b/libavcodec/vp9_metadata_bsf.c
> @@ -0,0 +1,143 @@
> +/*
> + * 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_vp9.h"
> +
> +typedef struct VP9MetadataContext {
> +    const AVClass *class;
> +
> +    CodedBitstreamContext *cbc;
> +    CodedBitstreamFragment fragment;
> +
> +    int color_space;
> +    int color_range;
> +
> +    int color_range_rgb_warned;
> +} VP9MetadataContext;
> +
> +
> +static int vp9_metadata_filter(AVBSFContext *bsf, AVPacket *out)
> +{
> +    VP9MetadataContext *ctx = bsf->priv_data;
> +    AVPacket *in = NULL;
> +    CodedBitstreamFragment *frag = &ctx->fragment;
> +    int err, i;
> +
> +    err = ff_bsf_get_packet(bsf, &in);
> +    if (err < 0)
> +        return err;
> +
> +    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;
> +    }
> +
> +    for (i = 0; i < frag->nb_units; i++) {
> +        VP9RawFrame *frame = frag->units[i].content;
> +        VP9RawFrameHeader *header = &frame->header;
> +
> +        if (ctx->color_space >= 0) {
> +            header->color_space = ctx->color_space;
> +        }
> +        if (ctx->color_range >= 0) {
> +            if (ctx->color_range == 0 &&
> +                header->color_space == VP9_CS_RGB &&
> +                !ctx->color_range_rgb_warned) {
> +                av_log(bsf, AV_LOG_WARNING, "Warning: color_range cannot "
> +                       "be set to limited in RGB streams.\n");
> +                ctx->color_range_rgb_warned = 1;
> +            } else {
> +                header->color_range = ctx->color_range;
> +            }
> +        }
> +    }
> +
> +    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)
> +        goto fail;
> +
> +    err = 0;
> +fail:
> +    ff_cbs_fragment_uninit(ctx->cbc, frag);
> +
> +    if (err < 0)
> +        av_packet_unref(out);
> +    av_packet_free(&in);
> +
> +    return err;
> +}
> +
> +static int vp9_metadata_init(AVBSFContext *bsf)
> +{
> +    VP9MetadataContext *ctx = bsf->priv_data;
> +
> +    return ff_cbs_init(&ctx->cbc, AV_CODEC_ID_VP9, bsf);
> +}
> +
> +static void vp9_metadata_close(AVBSFContext *bsf)
> +{
> +    VP9MetadataContext *ctx = bsf->priv_data;
> +    ff_cbs_close(&ctx->cbc);
> +}
> +
> +#define OFFSET(x) offsetof(VP9MetadataContext, x)
> +#define FLAGS (AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_BSF_PARAM)
> +static const AVOption vp9_metadata_options[] = {
> +    { "color_space", "Set colour space (see section 7.2.2)",
> +        OFFSET(color_space), AV_OPT_TYPE_INT,
> +        { .i64 = -1 }, -1, 7, FLAGS },

From -1 to VP9_CS_RGB maybe? And instead of saying to look at the spec
you could add named constants, so a simple ffmpeg -h bsf=vp9_metadata
will be enough.

> +    { "color_range", "Set colour range (see section 7.2.2)",
> +        OFFSET(color_range), AV_OPT_TYPE_INT,
> +        { .i64 = -1 }, -1, 1, FLAGS },

Same. Use the usual names tv/pc as in other parts of the code.

> +
> +    { NULL }
> +};
> +
> +static const AVClass vp9_metadata_class = {
> +    .class_name = "vp9_metadata_bsf",
> +    .item_name  = av_default_item_name,
> +    .option     = vp9_metadata_options,
> +    .version    = LIBAVUTIL_VERSION_INT,
> +};
> +
> +static const enum AVCodecID vp9_metadata_codec_ids[] = {
> +    AV_CODEC_ID_VP9, AV_CODEC_ID_NONE,
> +};
> +
> +const AVBitStreamFilter ff_vp9_metadata_bsf = {
> +    .name           = "vp9_metadata",
> +    .priv_data_size = sizeof(VP9MetadataContext),
> +    .priv_class     = &vp9_metadata_class,
> +    .init           = &vp9_metadata_init,
> +    .close          = &vp9_metadata_close,
> +    .filter         = &vp9_metadata_filter,
> +    .codec_ids      = vp9_metadata_codec_ids,
> +};
>