ffmpeg/libavfilter/vf_bbox.c
Stefano Sabatini 6b55aab01a lavfi: create buffer reference in filters which need to access the ref later
Also add internal function ff_null_start_frame_keep_ref().

Fix crash when a following filter (e.g. settb) will unref the reference
passed by start_frame(), and then the reference is accessed in
end_frame() through inlink->cur_buf.
2012-04-27 21:38:13 +02:00

116 lines
3.4 KiB
C

/*
* Copyright (c) 2012 Stefano Sabatini
*
* 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
* bounding box detection filter
*/
#include "libavutil/pixdesc.h"
#include "libavutil/timestamp.h"
#include "avfilter.h"
#include "bbox.h"
#include "internal.h"
typedef struct {
unsigned int frame;
int vsub, hsub;
} BBoxContext;
static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
{
BBoxContext *bbox = ctx->priv;
bbox->frame = 0;
return 0;
}
static int query_formats(AVFilterContext *ctx)
{
static const enum PixelFormat pix_fmts[] = {
PIX_FMT_YUV420P,
PIX_FMT_YUV444P,
PIX_FMT_YUV440P,
PIX_FMT_YUV422P,
PIX_FMT_YUV411P,
PIX_FMT_NONE,
};
avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
return 0;
}
static void end_frame(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
BBoxContext *bbox = ctx->priv;
AVFilterBufferRef *picref = inlink->cur_buf;
FFBoundingBox box;
int has_bbox, w, h;
has_bbox =
ff_calculate_bounding_box(&box,
picref->data[0], picref->linesize[0],
inlink->w, inlink->h, 16);
w = box.x2 - box.x1 + 1;
h = box.y2 - box.y1 + 1;
av_log(ctx, AV_LOG_INFO,
"n:%d pts:%s pts_time:%s", bbox->frame,
av_ts2str(picref->pts), av_ts2timestr(picref->pts, &inlink->time_base));
if (has_bbox) {
av_log(ctx, AV_LOG_INFO,
" x1:%d x2:%d y1:%d y2:%d w:%d h:%d"
" crop=%d:%d:%d:%d drawbox=%d:%d:%d:%d",
box.x1, box.x2, box.y1, box.y2, w, h,
w, h, box.x1, box.y1, /* crop params */
box.x1, box.y1, w, h); /* drawbox params */
}
av_log(ctx, AV_LOG_INFO, "\n");
bbox->frame++;
avfilter_unref_buffer(picref);
avfilter_end_frame(inlink->dst->outputs[0]);
}
AVFilter avfilter_vf_bbox = {
.name = "bbox",
.description = NULL_IF_CONFIG_SMALL("Compute bounding box for each frame."),
.priv_size = sizeof(BBoxContext),
.query_formats = query_formats,
.init = init,
.inputs = (const AVFilterPad[]) {
{ .name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.get_video_buffer = avfilter_null_get_video_buffer,
.start_frame = ff_null_start_frame_keep_ref,
.end_frame = end_frame,
.min_perms = AV_PERM_READ, },
{ .name = NULL }
},
.outputs = (const AVFilterPad[]) {
{ .name = "default",
.type = AVMEDIA_TYPE_VIDEO },
{ .name = NULL }
},
};