static int request_frame(AVFilterLink *outlink)
{
FifoContext *fifo = outlink->src->priv;
BufPic *tmp;
int ret;
if (!fifo->root.next) {
if ((ret = ff_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. */
ff_start_frame(outlink, fifo->root.next->picref);
ff_draw_slice (outlink, 0, outlink->h, 1);
ff_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;
}
static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref)
{
SetPTSContext *setpts = inlink->dst->priv;
double d;
AVFilterBufferRef *outpicref = avfilter_ref_buffer(inpicref, ~0);
if (isnan(setpts->var_values[VAR_STARTPTS]))
setpts->var_values[VAR_STARTPTS] = TS2D(inpicref->pts);
setpts->var_values[VAR_INTERLACED] = inpicref->video->interlaced;
setpts->var_values[VAR_PTS ] = TS2D(inpicref->pts);
setpts->var_values[VAR_POS ] = inpicref->pos == -1 ? NAN : inpicref->pos;
d = av_expr_eval(setpts->expr, setpts->var_values, NULL);
outpicref->pts = D2TS(d);
#ifdef DEBUG
av_log(inlink->dst, AV_LOG_DEBUG,
"n:%"PRId64" interlaced:%d pos:%"PRId64" pts:%"PRId64" t:%f -> pts:%"PRId64" t:%f\n",
(int64_t)setpts->var_values[VAR_N],
(int)setpts->var_values[VAR_INTERLACED],
inpicref ->pos,
inpicref ->pts, inpicref ->pts * av_q2d(inlink->time_base),
outpicref->pts, outpicref->pts * av_q2d(inlink->time_base));
#endif
setpts->var_values[VAR_N] += 1.0;
setpts->var_values[VAR_PREV_INPTS ] = TS2D(inpicref ->pts);
setpts->var_values[VAR_PREV_OUTPTS] = TS2D(outpicref->pts);
ff_start_frame(inlink->dst->outputs[0], outpicref);
}
static int start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)
{
TransContext *trans = inlink->dst->priv;
AVFilterLink *outlink = inlink->dst->outputs[0];
AVFilterBufferRef *buf_out;
if (trans->passthrough)
return ff_null_start_frame(inlink, picref);
outlink->out_buf = ff_get_video_buffer(outlink, AV_PERM_WRITE,
outlink->w, outlink->h);
if (!outlink->out_buf)
return AVERROR(ENOMEM);
outlink->out_buf->pts = picref->pts;
if (picref->video->sample_aspect_ratio.num == 0) {
outlink->out_buf->video->sample_aspect_ratio = picref->video->sample_aspect_ratio;
} else {
outlink->out_buf->video->sample_aspect_ratio.num = picref->video->sample_aspect_ratio.den;
outlink->out_buf->video->sample_aspect_ratio.den = picref->video->sample_aspect_ratio.num;
}
buf_out = avfilter_ref_buffer(outlink->out_buf, ~0);
if (!buf_out)
return AVERROR(ENOMEM);
return ff_start_frame(outlink, buf_out);
}
static int start_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref)
{
AVFilterBufferRef *outpicref = avfilter_ref_buffer(inpicref, ~0);
AVFilterContext *ctx = inlink->dst;
OverlayContext *over = ctx->priv;
if (!outpicref)
return AVERROR(ENOMEM);
outpicref->pts = av_rescale_q(outpicref->pts, ctx->inputs[MAIN]->time_base,
ctx->outputs[0]->time_base);
if (!over->overpicref || over->overpicref->pts < outpicref->pts) {
AVFilterBufferRef *old = over->overpicref;
over->overpicref = NULL;
ff_request_frame(ctx->inputs[OVERLAY]);
if (over->overpicref) {
if (old)
avfilter_unref_buffer(old);
} else
over->overpicref = old;
}
return ff_start_frame(inlink->dst->outputs[0], outpicref);
}
static int start_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref)
{
AVFilterContext *ctx = inlink->dst;
AVFilterLink *outlink = ctx->outputs[0];
AVFilterBufferRef *outpicref, *for_next_filter;
int ret = 0;
outpicref = avfilter_ref_buffer(inpicref, ~0);
if (!outpicref)
return AVERROR(ENOMEM);
for_next_filter = avfilter_ref_buffer(outpicref, ~0);
if (!for_next_filter) {
avfilter_unref_bufferp(&outpicref);
return AVERROR(ENOMEM);
}
ret = ff_start_frame(outlink, for_next_filter);
if (ret < 0) {
avfilter_unref_bufferp(&outpicref);
return ret;
}
outlink->out_buf = outpicref;
return 0;
}
static int end_frame(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
AlphaMergeContext *merge = ctx->priv;
int is_alpha = (inlink == ctx->inputs[1]);
struct FFBufQueue *queue =
(is_alpha ? &merge->queue_alpha : &merge->queue_main);
ff_bufqueue_add(ctx, queue, inlink->cur_buf);
inlink->cur_buf = NULL;
while (1) {
AVFilterBufferRef *main_buf, *alpha_buf;
if (!ff_bufqueue_peek(&merge->queue_main, 0) ||
!ff_bufqueue_peek(&merge->queue_alpha, 0)) break;
main_buf = ff_bufqueue_get(&merge->queue_main);
alpha_buf = ff_bufqueue_get(&merge->queue_alpha);
ctx->outputs[0]->out_buf = main_buf;
ff_start_frame(ctx->outputs[0], avfilter_ref_buffer(main_buf, ~0));
merge->frame_requested = 0;
draw_frame(ctx, main_buf, alpha_buf);
ff_end_frame(ctx->outputs[0]);
avfilter_unref_buffer(alpha_buf);
}
return 0;
}
static void start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
{
AspectContext *aspect = link->dst->priv;
picref->video->pixel_aspect = aspect->aspect;
ff_start_frame(link->dst->outputs[0], picref);
}
static int request_frame(AVFilterLink *outlink)
{
AVFilterContext *ctx = outlink->src;
SelectContext *select = ctx->priv;
AVFilterLink *inlink = outlink->src->inputs[0];
select->select = 0;
if (av_fifo_size(select->pending_frames)) {
AVFilterBufferRef *picref;
av_fifo_generic_read(select->pending_frames, &picref, sizeof(picref), NULL);
ff_start_frame(outlink, avfilter_ref_buffer(picref, ~0));
ff_draw_slice(outlink, 0, outlink->h, 1);
ff_end_frame(outlink);
avfilter_unref_buffer(picref);
return 0;
}
while (!select->select) {
int ret = ff_request_frame(inlink);
if (ret < 0)
return ret;
}
return 0;
}
static int start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
{
AspectContext *aspect = link->dst->priv;
picref->video->pixel_aspect = aspect->aspect;
link->cur_buf = NULL;
return ff_start_frame(link->dst->outputs[0], picref);
}
static void start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
{
AVFilterBufferRef *outpicref = avfilter_ref_buffer(picref, ~0);
link->dst->outputs[0]->out_buf = outpicref;
ff_start_frame(link->dst->outputs[0], outpicref);
}
static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)
{
AVFilterContext *ctx = inlink->dst;
int i;
for (i = 0; i < ctx->nb_outputs; i++)
ff_start_frame(ctx->outputs[i],
avfilter_ref_buffer(picref, ~AV_PERM_WRITE));
}
static int start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
{
AVFilterContext *ctx = link->dst;
ColorMatrixContext *color = ctx->priv;
AVFilterBufferRef *outpicref = avfilter_ref_buffer(picref, ~0);
color->outpicref = outpicref;
return ff_start_frame(link->dst->outputs[0], outpicref);
}
static int filter_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref)
{
SetPTSContext *setpts = inlink->dst->priv;
double d;
AVFilterBufferRef *outpicref = avfilter_ref_buffer(inpicref, ~0);
if (!outpicref)
return AVERROR(ENOMEM);
if (isnan(setpts->var_values[VAR_STARTPTS])) {
setpts->var_values[VAR_STARTPTS] = TS2D(inpicref->pts);
setpts->var_values[VAR_STARTT ] = TS2T(inpicref->pts, inlink->time_base);
}
setpts->var_values[VAR_PTS ] = TS2D(inpicref->pts);
setpts->var_values[VAR_T ] = TS2T(inpicref->pts, inlink->time_base);
setpts->var_values[VAR_POS ] = inpicref->pos == -1 ? NAN : inpicref->pos;
switch (inlink->type) {
case AVMEDIA_TYPE_VIDEO:
setpts->var_values[VAR_INTERLACED] = inpicref->video->interlaced;
break;
case AVMEDIA_TYPE_AUDIO:
setpts->var_values[VAR_NB_SAMPLES] = inpicref->audio->nb_samples;
break;
}
d = av_expr_eval(setpts->expr, setpts->var_values, NULL);
outpicref->pts = D2TS(d);
setpts->var_values[VAR_PREV_INPTS ] = TS2D(inpicref ->pts);
setpts->var_values[VAR_PREV_INT ] = TS2T(inpicref ->pts, inlink->time_base);
setpts->var_values[VAR_PREV_OUTPTS] = TS2D(outpicref->pts);
setpts->var_values[VAR_PREV_OUTT] = TS2T(outpicref->pts, inlink->time_base);
av_dlog(inlink->dst,
"n:%"PRId64" interlaced:%d nb_samples:%d nb_consumed_samples:%d "
"pos:%"PRId64" pts:%"PRId64" t:%f -> pts:%"PRId64" t:%f\n",
(int64_t)setpts->var_values[VAR_N],
(int)setpts->var_values[VAR_INTERLACED],
(int)setpts->var_values[VAR_NB_SAMPLES],
(int)setpts->var_values[VAR_NB_CONSUMED_SAMPLES],
(int64_t)setpts->var_values[VAR_POS],
(int64_t)setpts->var_values[VAR_PREV_INPTS],
setpts->var_values[VAR_PREV_INT],
(int64_t)setpts->var_values[VAR_PREV_OUTPTS],
setpts->var_values[VAR_PREV_OUTT]);
setpts->var_values[VAR_N] += 1.0;
if (setpts->type == AVMEDIA_TYPE_AUDIO) {
setpts->var_values[VAR_NB_CONSUMED_SAMPLES] += inpicref->audio->nb_samples;
return ff_filter_samples(inlink->dst->outputs[0], outpicref);
} else
return ff_start_frame (inlink->dst->outputs[0], outpicref);
}
static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref)
{
AVFilterContext *ctx = inlink->dst;
AVFilterLink *outlink = ctx->outputs[0];
AVFilterBufferRef *outpicref;
outpicref = avfilter_ref_buffer(inpicref, ~0);
outlink->out_buf = outpicref;
ff_start_frame(outlink, outpicref);
}
static int end_frame(AVFilterLink *inlink)
{
int i, j, best_frame_idx = 0;
double avg_hist[HIST_SIZE] = {0}, sq_err, min_sq_err = -1;
AVFilterLink *outlink = inlink->dst->outputs[0];
ThumbContext *thumb = inlink->dst->priv;
AVFilterContext *ctx = inlink->dst;
AVFilterBufferRef *picref;
// keep a reference of each frame
thumb->frames[thumb->n].buf = inlink->cur_buf;
inlink->cur_buf = NULL;
// no selection until the buffer of N frames is filled up
if (thumb->n < thumb->n_frames - 1) {
thumb->n++;
return 0;
}
// average histogram of the N frames
for (j = 0; j < FF_ARRAY_ELEMS(avg_hist); j++) {
for (i = 0; i < thumb->n_frames; i++)
avg_hist[j] += (double)thumb->frames[i].histogram[j];
avg_hist[j] /= thumb->n_frames;
}
// find the frame closer to the average using the sum of squared errors
for (i = 0; i < thumb->n_frames; i++) {
sq_err = frame_sum_square_err(thumb->frames[i].histogram, avg_hist);
if (i == 0 || sq_err < min_sq_err)
best_frame_idx = i, min_sq_err = sq_err;
}
// free and reset everything (except the best frame buffer)
for (i = 0; i < thumb->n_frames; i++) {
memset(thumb->frames[i].histogram, 0, sizeof(thumb->frames[i].histogram));
if (i == best_frame_idx)
continue;
avfilter_unref_buffer(thumb->frames[i].buf);
thumb->frames[i].buf = NULL;
}
thumb->n = 0;
// raise the chosen one
picref = thumb->frames[best_frame_idx].buf;
av_log(ctx, AV_LOG_INFO, "frame id #%d (pts_time=%f) selected\n",
best_frame_idx, picref->pts * av_q2d(inlink->time_base));
ff_start_frame(outlink, picref);
thumb->frames[best_frame_idx].buf = NULL;
ff_draw_slice(outlink, 0, inlink->h, 1);
return ff_end_frame(outlink);
}
static int start_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref)
{
SetFieldContext *setfield = inlink->dst->priv;
AVFilterBufferRef *outpicref = avfilter_ref_buffer(inpicref, ~0);
if (setfield->mode == MODE_PROG) {
outpicref->video->interlaced = 0;
} else if (setfield->mode != MODE_AUTO) {
outpicref->video->interlaced = 1;
outpicref->video->top_field_first = setfield->mode;
}
return ff_start_frame(inlink->dst->outputs[0], outpicref);
}
static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)
{
AVFilterContext *ctx = inlink->dst;
TileContext *tile = ctx->priv;
AVFilterLink *outlink = ctx->outputs[0];
if (tile->current)
return;
outlink->out_buf = ff_get_video_buffer(outlink, AV_PERM_WRITE,
outlink->w, outlink->h);
avfilter_copy_buffer_ref_props(outlink->out_buf, picref);
outlink->out_buf->video->w = outlink->w;
outlink->out_buf->video->h = outlink->h;
ff_start_frame(outlink, outlink->out_buf);
}
static int start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)
{
AVFilterContext *ctx = inlink->dst;
int i, ret = 0;
for (i = 0; i < ctx->nb_outputs; i++) {
AVFilterBufferRef *buf_out = avfilter_ref_buffer(picref, ~AV_PERM_WRITE);
if (!buf_out)
return AVERROR(ENOMEM);
ret = ff_start_frame(ctx->outputs[i], buf_out);
if (ret < 0)
break;
}
return ret;
}
static int start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)
{
AVFilterContext *ctx = inlink->dst;
AVFilterLink *outlink = ctx->outputs[0];
if (av_cmp_q(inlink->time_base, outlink->time_base)) {
int64_t orig_pts = picref->pts;
picref->pts = av_rescale_q(picref->pts, inlink->time_base, outlink->time_base);
av_log(ctx, AV_LOG_DEBUG, "tb:%d/%d pts:%"PRId64" -> tb:%d/%d pts:%"PRId64"\n",
inlink ->time_base.num, inlink ->time_base.den, orig_pts,
outlink->time_base.num, outlink->time_base.den, picref->pts);
}
inlink->cur_buf = NULL;
return ff_start_frame(outlink, picref);
}
static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)
{
AVFilterContext *ctx = inlink->dst;
AVFilterLink *outlink = ctx->outputs[0];
AVFilterBufferRef *picref2 = picref;
if (av_cmp_q(inlink->time_base, outlink->time_base)) {
picref2 = avfilter_ref_buffer(picref, ~0);
picref2->pts = av_rescale_q(picref->pts, inlink->time_base, outlink->time_base);
av_log(ctx, AV_LOG_DEBUG, "tb:%d/%d pts:%"PRId64" -> tb:%d/%d pts:%"PRId64"\n",
inlink ->time_base.num, inlink ->time_base.den, picref ->pts,
outlink->time_base.num, outlink->time_base.den, picref2->pts);
avfilter_unref_buffer(picref);
}
ff_start_frame(outlink, picref2);
}
static int color_request_frame(AVFilterLink *link)
{
ColorContext *color = link->src->priv;
AVFilterBufferRef *picref = avfilter_get_video_buffer(link, AV_PERM_WRITE, color->w, color->h);
picref->video->sample_aspect_ratio = (AVRational) {1, 1};
picref->pts = color->pts++;
picref->pos = -1;
ff_start_frame(link, avfilter_ref_buffer(picref, ~0));
ff_fill_rectangle(&color->draw, &color->color, picref->data, picref->linesize,
0, 0, color->w, color->h);
ff_draw_slice(link, 0, color->h, 1);
ff_end_frame(link);
avfilter_unref_buffer(picref);
return 0;
}
static void start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
{
SliceContext *slice = link->dst->priv;
if (slice->use_random_h) {
slice->lcg_state = slice->lcg_state * 1664525 + 1013904223;
slice->h = 8 + (uint64_t)slice->lcg_state * 25 / UINT32_MAX;
}
/* ensure that slices play nice with chroma subsampling, and enforce
* a reasonable minimum size for the slices */
slice->h = FFMAX(8, slice->h & (-1 << slice->vshift));
av_log(link->dst, AV_LOG_DEBUG, "h:%d\n", slice->h);
ff_start_frame(link->dst->outputs[0], picref);
}
static int source_request_frame(AVFilterLink *outlink)
{
Frei0rContext *frei0r = outlink->src->priv;
AVFilterBufferRef *picref = ff_get_video_buffer(outlink, AV_PERM_WRITE, outlink->w, outlink->h);
picref->video->pixel_aspect = (AVRational) {1, 1};
picref->pts = frei0r->pts++;
picref->pos = -1;
ff_start_frame(outlink, avfilter_ref_buffer(picref, ~0));
frei0r->update(frei0r->instance, av_rescale_q(picref->pts, frei0r->time_base, (AVRational){1,1000}),
NULL, (uint32_t *)picref->data[0]);
ff_draw_slice(outlink, 0, outlink->h, 1);
ff_end_frame(outlink);
avfilter_unref_buffer(picref);
return 0;
}
static int start_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref)
{
AVFilterLink *outlink = inlink->dst->outputs[0];
AVFilterBufferRef *outpicref;
if (inpicref->perms & AV_PERM_PRESERVE) {
outpicref = ff_get_video_buffer(outlink, AV_PERM_WRITE,
outlink->w, outlink->h);
avfilter_copy_buffer_ref_props(outpicref, inpicref);
outpicref->video->w = outlink->w;
outpicref->video->h = outlink->h;
} else
outpicref = inpicref;
outlink->out_buf = outpicref;
return ff_start_frame(outlink, avfilter_ref_buffer(outpicref, ~0));
}
int ff_filter_frame(AVFilterLink *link, AVFilterBufferRef *frame)
{
int ret;
FF_TPRINTF_START(NULL, filter_frame); ff_tlog_link(NULL, link, 1); ff_tlog(NULL, " "); ff_tlog_ref(NULL, frame, 1);
switch (link->type) {
case AVMEDIA_TYPE_VIDEO:
if((ret = ff_start_frame(link, frame)) < 0)
return ret;
if((ret = ff_draw_slice(link, 0, frame->video->h, 1)) < 0)
return ret;
if((ret = ff_end_frame(link)) < 0)
return ret;
return ret;
case AVMEDIA_TYPE_AUDIO:
return ff_filter_samples(link, frame);
default: return AVERROR(EINVAL);
}
}
static int start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)
{
PixdescTestContext *priv = inlink->dst->priv;
AVFilterLink *outlink = inlink->dst->outputs[0];
AVFilterBufferRef *outpicref, *for_next_filter;
int i, ret = 0;
outpicref = ff_get_video_buffer(outlink, AV_PERM_WRITE,
outlink->w, outlink->h);
if (!outpicref)
return AVERROR(ENOMEM);
avfilter_copy_buffer_ref_props(outpicref, picref);
for (i = 0; i < 4; i++) {
int h = outlink->h;
h = i == 1 || i == 2 ? h>>priv->pix_desc->log2_chroma_h : h;
if (outpicref->data[i]) {
uint8_t *data = outpicref->data[i] +
(outpicref->linesize[i] > 0 ? 0 : outpicref->linesize[i] * (h-1));
memset(data, 0, FFABS(outpicref->linesize[i]) * h);
}
}
/* copy palette */
if (priv->pix_desc->flags & PIX_FMT_PAL ||
priv->pix_desc->flags & PIX_FMT_PSEUDOPAL)
memcpy(outpicref->data[1], outpicref->data[1], 256*4);
for_next_filter = avfilter_ref_buffer(outpicref, ~0);
if (for_next_filter)
ret = ff_start_frame(outlink, for_next_filter);
else
ret = AVERROR(ENOMEM);
if (ret < 0) {
avfilter_unref_bufferp(&outpicref);
return ret;
}
outlink->out_buf = outpicref;
return 0;
}
static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)
{
SelectContext *select = inlink->dst->priv;
select->select = select_frame(inlink->dst, picref);
if (select->select) {
/* frame was requested through poll_frame */
if (select->cache_frames) {
if (!av_fifo_space(select->pending_frames))
av_log(inlink->dst, AV_LOG_ERROR,
"Buffering limit reached, cannot cache more frames\n");
else
av_fifo_generic_write(select->pending_frames, &picref,
sizeof(picref), NULL);
return;
}
ff_start_frame(inlink->dst->outputs[0], avfilter_ref_buffer(picref, ~0));
}
}
static int color_request_frame(AVFilterLink *link)
{
ColorContext *color = link->src->priv;
AVFilterBufferRef *picref = ff_get_video_buffer(link, AV_PERM_WRITE, color->w, color->h);
AVFilterBufferRef *buf_out;
int ret;
if (!picref)
return AVERROR(ENOMEM);
picref->video->pixel_aspect = (AVRational) {1, 1};
picref->pts = color->pts++;
picref->pos = -1;
buf_out = avfilter_ref_buffer(picref, ~0);
if (!buf_out) {
ret = AVERROR(ENOMEM);
goto fail;
}
ret = ff_start_frame(link, buf_out);
if (ret < 0)
goto fail;
ff_draw_rectangle(picref->data, picref->linesize,
color->line, color->line_step, color->hsub, color->vsub,
0, 0, color->w, color->h);
ret = ff_draw_slice(link, 0, color->h, 1);
if (ret < 0)
goto fail;
ret = ff_end_frame(link);
fail:
avfilter_unref_buffer(picref);
return ret;
}
static int source_request_frame(AVFilterLink *outlink)
{
Frei0rContext *frei0r = outlink->src->priv;
AVFilterBufferRef *picref = ff_get_video_buffer(outlink, AV_PERM_WRITE, outlink->w, outlink->h);
AVFilterBufferRef *buf_out;
int ret;
if (!picref)
return AVERROR(ENOMEM);
picref->video->pixel_aspect = (AVRational) {1, 1};
picref->pts = frei0r->pts++;
picref->pos = -1;
buf_out = avfilter_ref_buffer(picref, ~0);
if (!buf_out) {
ret = AVERROR(ENOMEM);
goto fail;
}
ret = ff_start_frame(outlink, buf_out);
if (ret < 0)
goto fail;
frei0r->update(frei0r->instance, av_rescale_q(picref->pts, frei0r->time_base, (AVRational){1,1000}),
NULL, (uint32_t *)picref->data[0]);
ret = ff_draw_slice(outlink, 0, outlink->h, 1);
if (ret < 0)
goto fail;
ret = ff_end_frame(outlink);
fail:
avfilter_unref_buffer(picref);
return ret;
}
static int request_frame(AVFilterLink *outlink)
{
FifoContext *fifo = outlink->src->priv;
int ret = 0;
if (!fifo->root.next) {
if ((ret = ff_request_frame(outlink->src->inputs[0])) < 0)
return ret;
av_assert0(fifo->root.next);
}
/* by doing this, we give ownership of the reference to the next filter,
* so we don't have to worry about dereferencing it ourselves. */
switch (outlink->type) {
case AVMEDIA_TYPE_VIDEO:
if ((ret = ff_start_frame(outlink, fifo->root.next->buf)) < 0 ||
(ret = ff_draw_slice(outlink, 0, outlink->h, 1)) < 0 ||
(ret = ff_end_frame(outlink)) < 0)
return ret;
queue_pop(fifo);
break;
case AVMEDIA_TYPE_AUDIO:
if (outlink->request_samples) {
return return_audio_frame(outlink->src);
} else {
ret = ff_filter_samples(outlink, fifo->root.next->buf);
queue_pop(fifo);
}
break;
default:
return AVERROR(EINVAL);
}
return ret;
}