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FFmpeg/libavfilter/vf_vflip.c
Andreas Rheinhardt 8be701d9f7 avfilter/avfilter: Add numbers of (in|out)pads directly to AVFilter
Up until now, an AVFilter's lists of input and output AVFilterPads
were terminated by a sentinel and the only way to get the length
of these lists was by using avfilter_pad_count(). This has two
drawbacks: first, sizeof(AVFilterPad) is not negligible
(i.e. 64B on 64bit systems); second, getting the size involves
a function call instead of just reading the data.

This commit therefore changes this. The sentinels are removed and new
private fields nb_inputs and nb_outputs are added to AVFilter that
contain the number of elements of the respective AVFilterPad array.

Given that AVFilter.(in|out)puts are the only arrays of zero-terminated
AVFilterPads an API user has access to (AVFilterContext.(in|out)put_pads
are not zero-terminated and they already have a size field) the argument
to avfilter_pad_count() is always one of these lists, so it just has to
find the filter the list belongs to and read said number. This is slower
than before, but a replacement function that just reads the internal numbers
that users are expected to switch to will be added soon; and furthermore,
avfilter_pad_count() is probably never called in hot loops anyway.

This saves about 49KiB from the binary; notice that these sentinels are
not in .bss despite being zeroed: they are in .data.rel.ro due to the
non-sentinels.

Reviewed-by: Nicolas George <george@nsup.org>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2021-08-20 12:53:58 +02:00

154 lines
4.3 KiB
C

/*
* Copyright (c) 2007 Bobby Bingham
*
* 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
*/
/**
* @file
* video vertical flip filter
*/
#include "libavutil/internal.h"
#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"
#include "avfilter.h"
#include "internal.h"
#include "video.h"
typedef struct FlipContext {
const AVClass *class;
int vsub; ///< vertical chroma subsampling
int bayer;
} FlipContext;
static const AVOption vflip_options[] = {
{ NULL }
};
AVFILTER_DEFINE_CLASS(vflip);
static int config_input(AVFilterLink *link)
{
FlipContext *flip = link->dst->priv;
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);
flip->vsub = desc->log2_chroma_h;
flip->bayer = !!(desc->flags & AV_PIX_FMT_FLAG_BAYER);
return 0;
}
static AVFrame *get_video_buffer(AVFilterLink *link, int w, int h)
{
FlipContext *flip = link->dst->priv;
AVFrame *frame;
int i;
frame = ff_get_video_buffer(link->dst->outputs[0], w, h);
if (!frame)
return NULL;
for (i = 0; i < 4; i ++) {
int vsub = i == 1 || i == 2 ? flip->vsub : 0;
int height = AV_CEIL_RSHIFT(h, vsub);
if (frame->data[i]) {
frame->data[i] += (height - 1) * frame->linesize[i];
frame->linesize[i] = -frame->linesize[i];
}
}
return frame;
}
static int flip_bayer(AVFilterLink *link, AVFrame *in)
{
AVFilterContext *ctx = link->dst;
AVFilterLink *outlink = ctx->outputs[0];
AVFrame *out;
uint8_t *inrow = in->data[0], *outrow;
int i, width = outlink->w << (av_pix_fmt_desc_get(link->format)->comp[0].step > 1);
if (outlink->h & 1) {
av_log(ctx, AV_LOG_ERROR, "Bayer vertical flip needs even height\n");
return AVERROR_INVALIDDATA;
}
out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
if (!out) {
av_frame_free(&in);
return AVERROR(ENOMEM);
}
av_frame_copy_props(out, in);
outrow = out->data[0] + out->linesize[0] * (outlink->h - 2);
for (i = 0; i < outlink->h >> 1; i++) {
memcpy(outrow, inrow, width);
memcpy(outrow + out->linesize[0], inrow + in->linesize[0], width);
inrow += 2 * in->linesize[0];
outrow -= 2 * out->linesize[0];
}
av_frame_free(&in);
return ff_filter_frame(outlink, out);
}
static int filter_frame(AVFilterLink *link, AVFrame *frame)
{
FlipContext *flip = link->dst->priv;
int i;
if (flip->bayer)
return flip_bayer(link, frame);
for (i = 0; i < 4; i ++) {
int vsub = i == 1 || i == 2 ? flip->vsub : 0;
int height = AV_CEIL_RSHIFT(link->h, vsub);
if (frame->data[i]) {
frame->data[i] += (height - 1) * frame->linesize[i];
frame->linesize[i] = -frame->linesize[i];
}
}
return ff_filter_frame(link->dst->outputs[0], frame);
}
static const AVFilterPad avfilter_vf_vflip_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.get_buffer.video = get_video_buffer,
.filter_frame = filter_frame,
.config_props = config_input,
},
};
static const AVFilterPad avfilter_vf_vflip_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
},
};
const AVFilter ff_vf_vflip = {
.name = "vflip",
.description = NULL_IF_CONFIG_SMALL("Flip the input video vertically."),
.priv_size = sizeof(FlipContext),
.priv_class = &vflip_class,
FILTER_INPUTS(avfilter_vf_vflip_inputs),
FILTER_OUTPUTS(avfilter_vf_vflip_outputs),
.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
};