[FFmpeg-devel] [PATCH v4 5/6] vf_ccrepack: Add new filter to repack CEA-708 side data
Devin Heitmueller
devin.heitmueller at ltnglobal.com
Tue May 2 17:17:22 EEST 2023
Hi Lance,
On Sun, Apr 30, 2023 at 6:42 PM Lance Wang <lance.lmwang at gmail.com> wrote:
>
> On Fri, Apr 28, 2023 at 11:43 PM Devin Heitmueller <
> devin.heitmueller at ltnglobal.com> wrote:
>
> > THis filter can correct certain issues seen from upstream sources
> > where the cc_count is not properly set or the CEA-608 tuples are
> > not at the start of the payload as expected.
> >
> > Make use of the ccfifo to extract and immediately repack the CEA-708
> > side data, thereby removing any extra padding and ensuring the 608
> > tuples are at the front of the payload.
> >
> > Signed-off-by: Devin Heitmueller <dheitmueller at ltnglobal.com>
> > ---
> > doc/filters.texi | 10 +++++
> > libavfilter/Makefile | 1 +
> > libavfilter/allfilters.c | 1 +
> > libavfilter/vf_ccrepack.c | 100
> > ++++++++++++++++++++++++++++++++++++++++++++++
> > 4 files changed, 112 insertions(+)
> > create mode 100644 libavfilter/vf_ccrepack.c
> >
> > diff --git a/doc/filters.texi b/doc/filters.texi
> > index 5dde799..9f67a00 100644
> > --- a/doc/filters.texi
> > +++ b/doc/filters.texi
> > @@ -8936,6 +8936,16 @@ Only deinterlace frames marked as interlaced.
> > The default value is @code{all}.
> > @end table
> >
> > + at section ccrepack
> > +
> > +Repack CEA-708 closed captioning side data
> > +
> > +This filter fixes various issues seen with commerical encoders
> > +related to upstream malformed CEA-708 payloads, specifically
> > +incorrect number of tuples (wrong cc_count for the target FPS),
> > +and incorrect ordering of tuples (i.e. the CEA-608 tuples are not at
> > +the first entries in the payload).
> > +
> > @section cas
> >
> > Apply Contrast Adaptive Sharpen filter to video stream.
> > diff --git a/libavfilter/Makefile b/libavfilter/Makefile
> > index 628ade8..3d0b3ad 100644
> > --- a/libavfilter/Makefile
> > +++ b/libavfilter/Makefile
> > @@ -212,6 +212,7 @@ OBJS-$(CONFIG_BOXBLUR_OPENCL_FILTER) +=
> > vf_avgblur_opencl.o opencl.o \
> > opencl/avgblur.o boxblur.o
> > OBJS-$(CONFIG_BWDIF_FILTER) += vf_bwdif.o yadif_common.o
> > OBJS-$(CONFIG_CAS_FILTER) += vf_cas.o
> > +OBJS-$(CONFIG_CCREPACK_FILTER) += vf_ccrepack.o
> > OBJS-$(CONFIG_CHROMABER_VULKAN_FILTER) += vf_chromaber_vulkan.o
> > vulkan.o vulkan_filter.o
> > OBJS-$(CONFIG_CHROMAHOLD_FILTER) += vf_chromakey.o
> > OBJS-$(CONFIG_CHROMAKEY_FILTER) += vf_chromakey.o
> > diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
> > index d7db46c..b38550b 100644
> > --- a/libavfilter/allfilters.c
> > +++ b/libavfilter/allfilters.c
> > @@ -196,6 +196,7 @@ extern const AVFilter ff_vf_boxblur;
> > extern const AVFilter ff_vf_boxblur_opencl;
> > extern const AVFilter ff_vf_bwdif;
> > extern const AVFilter ff_vf_cas;
> > +extern const AVFilter ff_vf_ccrepack;
> > extern const AVFilter ff_vf_chromaber_vulkan;
> > extern const AVFilter ff_vf_chromahold;
> > extern const AVFilter ff_vf_chromakey;
> > diff --git a/libavfilter/vf_ccrepack.c b/libavfilter/vf_ccrepack.c
> > new file mode 100644
> > index 0000000..fb9120c
> > --- /dev/null
> > +++ b/libavfilter/vf_ccrepack.c
> > @@ -0,0 +1,100 @@
> > +/*
> > + * CEA-708 Closed Caption Repacker
> > + * Copyright (c) 2023 LTN Global Communications
> > + *
> > + * Author: Devin Heitmueller <dheitmueller at ltnglobal.com>
> > + *
> > + * 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
> > + */
> > +
> > +/*
> > + * Repackage CEA-708 arrays, which deals with incorrect cc_count for a
> > given
> > + * output framerate, and incorrect 708 padding.
> > + *
> > + * See CEA CEA-10-A "EIA-708-B Implementation Guidance", Section 26.5
> > + * "Grouping DTVCC Data Within user_data() Structure"
> > + */
> > +
> > +#include "avfilter.h"
> > +#include "internal.h"
> > +#include "ccfifo.h"
> > +#include "libavutil/opt.h"
> > +
> > +typedef struct CCRepackContext
> > +{
> > + const AVClass *class;
> > + AVCCFifo *cc_fifo;
> > +} CCRepackContext;
> > +
> > +static const AVOption ccrepack_options[] = {
> > + { NULL }
> > +};
> > +
> >
> unused code as no option
>
>
> > +AVFILTER_DEFINE_CLASS(ccrepack);
> > +
> > +static int config_input(AVFilterLink *link)
> > +{
> > + CCRepackContext *ctx = link->dst->priv;
> > +
> > + if (!(ctx->cc_fifo = ff_ccfifo_alloc(&link->frame_rate, ctx)))
> > + av_log(ctx, AV_LOG_VERBOSE, "Failure to setup CC FIFO queue\n");
> > +
> >
>
> it's better to return error and print error log here.
>
>
> > + return 0;
> > +}
> > +
> > +static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
> > +{
> > + CCRepackContext *ctx = inlink->dst->priv;
> > + AVFilterLink *outlink = inlink->dst->outputs[0];
> > +
> > + ff_ccfifo_extract(ctx->cc_fifo, frame);
> > + ff_ccfifo_inject(ctx->cc_fifo, frame);
> > +
> >
> It's better to check return of function here.
>
>
> > + return ff_filter_frame(outlink, frame);
> > +}
> > +
> > +static av_cold void uninit(AVFilterContext *ctx)
> > +{
> > + CCRepackContext *s = ctx->priv;
> > + ff_ccfifo_freep(&s->cc_fifo);
> > +}
> > +
> > +static const AVFilterPad avfilter_vf_ccrepack_inputs[] = {
> > + {
> > + .name = "default",
> > + .type = AVMEDIA_TYPE_VIDEO,
> > + .filter_frame = filter_frame,
> > + .config_props = config_input,
> > + },
> > +};
> > +
> > +static const AVFilterPad avfilter_vf_ccrepack_outputs[] = {
> > + {
> > + .name = "default",
> > + .type = AVMEDIA_TYPE_VIDEO,
> > + },
> > +};
> > +
> > +AVFilter ff_vf_ccrepack = {
> > + .name = "ccrepack",
> > + .description = NULL_IF_CONFIG_SMALL("Repack CEA-708 closed caption
> > metadata"),
> > + .uninit = uninit,
> > + .priv_size = sizeof(CCRepackContext),
> > + .priv_class = &ccrepack_class,
> > + FILTER_INPUTS(avfilter_vf_ccrepack_inputs),
> > + FILTER_OUTPUTS(avfilter_vf_ccrepack_outputs),
> > +};
> > --
> > 1.8.3.1
> >
> > _______________________________________________
> > ffmpeg-devel mailing list
> > ffmpeg-devel at ffmpeg.org
> > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
> >
> > To unsubscribe, visit link above, or email
> > ffmpeg-devel-request at ffmpeg.org with subject "unsubscribe".
> >
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>
> To unsubscribe, visit link above, or email
> ffmpeg-devel-request at ffmpeg.org with subject "unsubscribe".
These are all reasonable comments, and in fact largely the result of
my not reflecting changes I made to the API in the last round, where
we now have the ff_ccfifo_alloc() call succeed even if the output
framerate is not supported.
I'll roll these fixes into the next series.
Devin
--
Devin Heitmueller, Senior Software Engineer
LTN Global Communications
o: +1 (301) 363-1001
w: https://ltnglobal.com e: devin.heitmueller at ltnglobal.com
More information about the ffmpeg-devel
mailing list