120 lines
3.6 KiB
C
120 lines
3.6 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
|
|
* FIFO buffering video filter
|
|
*/
|
|
|
|
#include "avfilter.h"
|
|
|
|
typedef struct BufPic {
|
|
AVFilterBufferRef *picref;
|
|
struct BufPic *next;
|
|
} BufPic;
|
|
|
|
typedef struct {
|
|
BufPic root;
|
|
BufPic *last; ///< last buffered picture
|
|
} FifoContext;
|
|
|
|
static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
|
|
{
|
|
FifoContext *fifo = ctx->priv;
|
|
fifo->last = &fifo->root;
|
|
|
|
av_log(ctx, AV_LOG_INFO, "\n");
|
|
return 0;
|
|
}
|
|
|
|
static av_cold void uninit(AVFilterContext *ctx)
|
|
{
|
|
FifoContext *fifo = ctx->priv;
|
|
BufPic *pic, *tmp;
|
|
|
|
for (pic = fifo->root.next; pic; pic = tmp) {
|
|
tmp = pic->next;
|
|
avfilter_unref_buffer(pic->picref);
|
|
av_free(pic);
|
|
}
|
|
}
|
|
|
|
static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)
|
|
{
|
|
FifoContext *fifo = inlink->dst->priv;
|
|
|
|
fifo->last->next = av_mallocz(sizeof(BufPic));
|
|
fifo->last = fifo->last->next;
|
|
fifo->last->picref = picref;
|
|
}
|
|
|
|
static void end_frame(AVFilterLink *inlink) { }
|
|
|
|
static void draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir) { }
|
|
|
|
static int request_frame(AVFilterLink *outlink)
|
|
{
|
|
FifoContext *fifo = outlink->src->priv;
|
|
BufPic *tmp;
|
|
int ret;
|
|
|
|
if (!fifo->root.next) {
|
|
if ((ret = avfilter_request_frame(outlink->src->inputs[0])) < 0)
|
|
return ret;
|
|
}
|
|
|
|
/* by doing this, we give ownership of the reference to the next filter,
|
|
* so we don't have to worry about dereferencing it ourselves. */
|
|
avfilter_start_frame(outlink, fifo->root.next->picref);
|
|
avfilter_draw_slice (outlink, 0, outlink->h, 1);
|
|
avfilter_end_frame (outlink);
|
|
|
|
if (fifo->last == fifo->root.next)
|
|
fifo->last = &fifo->root;
|
|
tmp = fifo->root.next->next;
|
|
av_free(fifo->root.next);
|
|
fifo->root.next = tmp;
|
|
|
|
return 0;
|
|
}
|
|
|
|
AVFilter avfilter_vf_fifo = {
|
|
.name = "fifo",
|
|
.description = NULL_IF_CONFIG_SMALL("Buffer input images and send them when they are requested."),
|
|
|
|
.init = init,
|
|
.uninit = uninit,
|
|
|
|
.priv_size = sizeof(FifoContext),
|
|
|
|
.inputs = (const AVFilterPad[]) {{ .name = "default",
|
|
.type = AVMEDIA_TYPE_VIDEO,
|
|
.get_video_buffer= avfilter_null_get_video_buffer,
|
|
.start_frame = start_frame,
|
|
.draw_slice = draw_slice,
|
|
.end_frame = end_frame,
|
|
.rej_perms = AV_PERM_REUSE2, },
|
|
{ .name = NULL}},
|
|
.outputs = (const AVFilterPad[]) {{ .name = "default",
|
|
.type = AVMEDIA_TYPE_VIDEO,
|
|
.request_frame = request_frame, },
|
|
{ .name = NULL}},
|
|
};
|