[FFmpeg-devel] [PATCH] extractplanes filter
Paul B Mahol
onemda at gmail.com
Wed May 1 20:39:11 CEST 2013
On 5/1/13, Nicolas George <nicolas.george at normalesup.org> wrote:
> Le primidi 11 floreal, an CCXXI, Paul B Mahol a ecrit :
>> Signed-off-by: Paul B Mahol <onemda at gmail.com>
>> ---
>> libavfilter/Makefile | 1 +
>> libavfilter/allfilters.c | 1 +
>> libavfilter/vf_extractplanes.c | 179
>> +++++++++++++++++++++++++++++++++++++++++
>> 3 files changed, 181 insertions(+)
>> create mode 100644 libavfilter/vf_extractplanes.c
>
> Missing documentation.
Will be added.
>
>>
>> diff --git a/libavfilter/Makefile b/libavfilter/Makefile
>> index d4ecf95..3e8e5c5 100644
>> --- a/libavfilter/Makefile
>> +++ b/libavfilter/Makefile
>> @@ -120,6 +120,7 @@ OBJS-$(CONFIG_DESHAKE_FILTER) +=
>> vf_deshake.o
>> OBJS-$(CONFIG_DRAWBOX_FILTER) += vf_drawbox.o
>> OBJS-$(CONFIG_DRAWTEXT_FILTER) += vf_drawtext.o
>> OBJS-$(CONFIG_EDGEDETECT_FILTER) += vf_edgedetect.o
>> +OBJS-$(CONFIG_EXTRACTPLANES_FILTER) += vf_extractplanes.o
>> OBJS-$(CONFIG_FADE_FILTER) += vf_fade.o
>> OBJS-$(CONFIG_FIELD_FILTER) += vf_field.o
>> OBJS-$(CONFIG_FIELDMATCH_FILTER) += vf_fieldmatch.o
>> diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
>> index 97e558b..a193d4c 100644
>> --- a/libavfilter/allfilters.c
>> +++ b/libavfilter/allfilters.c
>> @@ -118,6 +118,7 @@ void avfilter_register_all(void)
>> REGISTER_FILTER(DRAWBOX, drawbox, vf);
>> REGISTER_FILTER(DRAWTEXT, drawtext, vf);
>> REGISTER_FILTER(EDGEDETECT, edgedetect, vf);
>> + REGISTER_FILTER(EXTRACTPLANES, extractplanes, vf);
>> REGISTER_FILTER(FADE, fade, vf);
>> REGISTER_FILTER(FIELD, field, vf);
>> REGISTER_FILTER(FIELDMATCH, fieldmatch, vf);
>> diff --git a/libavfilter/vf_extractplanes.c
>> b/libavfilter/vf_extractplanes.c
>> new file mode 100644
>> index 0000000..79363d8
>> --- /dev/null
>> +++ b/libavfilter/vf_extractplanes.c
>> @@ -0,0 +1,179 @@
>> +/*
>> + * Copyright (c) 2013 Paul B Mahol
>> + *
>> + * 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/opt.h"
>> +#include "libavutil/imgutils.h"
>> +#include "libavutil/pixdesc.h"
>> +#include "avfilter.h"
>> +#include "internal.h"
>> +
>> +typedef struct {
>> + const AVClass *class;
>> + int flags;
>> + int map[4];
>> +} ExtractPlanesContext;
>> +
>> +#define OFFSET(x) offsetof(ExtractPlanesContext, x)
>> +#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
>> +static const AVOption extractplanes_options[] = {
>> + { "planes", "set planes", OFFSET(flags), AV_OPT_TYPE_FLAGS,
>> {.i64=1}, 1, (1<<4)-1, FLAGS, "flags"},
>> + { "y", "set luma", 0, AV_OPT_TYPE_CONST, {.i64=1<<0}, 0, 0,
>> FLAGS, "flags"},
>> + { "u", "set u", 0, AV_OPT_TYPE_CONST, {.i64=1<<1}, 0, 0,
>> FLAGS, "flags"},
>> + { "v", "set v", 0, AV_OPT_TYPE_CONST, {.i64=1<<2}, 0, 0,
>> FLAGS, "flags"},
>> + { "g", "set green", 0, AV_OPT_TYPE_CONST, {.i64=1<<0}, 0, 0,
>> FLAGS, "flags"},
>> + { "b", "set blue", 0, AV_OPT_TYPE_CONST, {.i64=1<<1}, 0, 0,
>> FLAGS, "flags"},
>> + { "r", "set red", 0, AV_OPT_TYPE_CONST, {.i64=1<<2}, 0, 0,
>> FLAGS, "flags"},
>> + { "a", "set alpha", 0, AV_OPT_TYPE_CONST, {.i64=1<<3}, 0, 0,
>> FLAGS, "flags"},
>
> Maybe "set x" -> "x plane" would be more correct, I am not sure.
Yes, changed.
>
>> + { NULL }
>> +};
>> +
>> +AVFILTER_DEFINE_CLASS(extractplanes);
>> +
>> +static int query_formats(AVFilterContext *ctx)
>> +{
>> + static const enum AVPixelFormat in_pixfmts[] = {
>> + AV_PIX_FMT_YUV410P,
>> + AV_PIX_FMT_YUV411P,
>> + AV_PIX_FMT_YUV440P,
>> + AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUVA420P,
>> + AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUVA422P,
>> + AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P,
>> + AV_PIX_FMT_YUVJ440P, AV_PIX_FMT_YUVJ444P,
>> + AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUVA444P,
>> + AV_PIX_FMT_GRAY8A,
>> + AV_PIX_FMT_GBRP,
>> + AV_PIX_FMT_NONE,
>> + };
>> + static const enum AVPixelFormat out_pixfmts[] = {
>> + AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE,
>> + };
>> + int i;
>> +
>> + ff_formats_ref(ff_make_format_list(in_pixfmts),
>> &ctx->inputs[0]->out_formats);
>> + for (i = 0; i < ctx->nb_outputs; i++)
>> + ff_formats_ref(ff_make_format_list(out_pixfmts),
>> &ctx->outputs[i]->in_formats);
>> + return 0;
>> +}
>> +
>> +static int config_output(AVFilterLink *outlink)
>> +{
>> + AVFilterContext *ctx = outlink->src;
>> + AVFilterLink *inlink = ctx->inputs[0];
>> + ExtractPlanesContext *e = ctx->priv;
>> + const AVPixFmtDescriptor *desc =
>> av_pix_fmt_desc_get(inlink->format);
>> + int output;
>> +
>> + sscanf(outlink->srcpad->name, "out%d", &output);
>> +
>> + if (e->map[output] == 1 || e->map[output] == 2) {
>> + outlink->h = inlink->h >> desc->log2_chroma_h;
>> + outlink->w = inlink->w >> desc->log2_chroma_w;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static int init(AVFilterContext *ctx)
>
> Nit: init() before query_formats().
Moved.
>
>> +{
>> + ExtractPlanesContext *e = ctx->priv;
>> + int i;
>> +
>> + for (i = 0; i < 4; i++) {
>> + char name[32];
>> + AVFilterPad pad = { 0 };
>> +
>> + if (!(e->flags & (1 << i)))
>> + continue;
>> +
>> + e->map[ctx->nb_outputs] = i;
>
>> + snprintf(name, sizeof(name), "out%d", ctx->nb_outputs);
>> + pad.name = av_strdup(name);
>
> av_asprintf()
Changed.
>
>> + if (!pad.name)
>> + return AVERROR(ENOMEM);
>> + pad.type = AVMEDIA_TYPE_VIDEO;
>> + pad.config_props = config_output;
>> +
>> + ff_insert_outpad(ctx, ctx->nb_outputs, &pad);
>> + }
>
> There is no check that the planes specified exist. For example, the user
> could write "planes=r" and get the y plane instead if the input is yuv. But
> I do not consider it blocking.
Yes, I'm aware of that, either I could query for different formats if r/g/b are
set, or leave it to user by renaming r/g/b/y/u/v to c0/c1.., or just
return nothing
if input does not have r/g/b.
I think I will pick first one.
>
>> +
>> + return 0;
>> +}
>> +
>> +static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
>> +{
>> + AVFilterContext *ctx = inlink->dst;
>> + ExtractPlanesContext *e = ctx->priv;
>> + int i, ret = AVERROR_EOF;
>> +
>> + for (i = 0; i < ctx->nb_outputs; i++) {
>> + const int idx = e->map[i];
>> + AVFilterLink *outlink = ctx->outputs[i];
>> + AVFrame *out;
>> +
>> + if (outlink->closed || !frame->data[idx])
>> + continue;
>> +
>> + out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
>> + if (!out) {
>> + ret = AVERROR(ENOMEM);
>> + break;
>> + }
>> + av_frame_copy_props(out, frame);
>> +
>> + av_image_copy_plane(out->data[0], out->linesize[0],
>> + frame->data[idx], frame->linesize[idx],
>> + outlink->w, outlink->h);
>
>> + ret = ff_filter_frame(outlink, out);
>> + if (ret < 0)
>> + break;
>
> AVERROR_EOF needs to be handled separately, otherwise, the first closed
> output will cause the whole filter to shut down.
So return AVERROR_EOF only if EOF happend for all outputs and
otherwise just return 0?
>
>> + }
>> + av_frame_free(&frame);
>> + return ret;
>> +}
>> +
>> +static void uninit(AVFilterContext *ctx)
>> +{
>> + int i;
>> +
>> + for (i = 0; i < ctx->nb_outputs; i++)
>> + av_freep(&ctx->output_pads[i].name);
>> +}
>
> Unrelated, but I believe this should be done automatically.
greping shows its required.
>
>> +
>> +static const AVFilterPad extractplanes_inputs[] = {
>> + {
>> + .name = "default",
>> + .type = AVMEDIA_TYPE_VIDEO,
>> + .filter_frame = filter_frame,
>> + },
>> + { NULL }
>> +};
>> +
>> +AVFilter avfilter_vf_extractplanes = {
>> + .name = "extractplanes",
>> + .description = NULL_IF_CONFIG_SMALL("Extract planes as grayscale
>> frames."),
>> + .priv_size = sizeof(ExtractPlanesContext),
>> + .priv_class = &extractplanes_class,
>> + .init = init,
>> + .uninit = uninit,
>> + .query_formats = query_formats,
>> + .inputs = extractplanes_inputs,
>> + .outputs = NULL,
>> + .flags = AVFILTER_FLAG_DYNAMIC_OUTPUTS,
>> +};
>
> Good idea and good work, thanks.
>
> Regards,
>
> --
> Nicolas George
>
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