mpv/player/lavfi.c

820 lines
25 KiB
C

/*
* This file is part of mpv.
*
* mpv 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.
*
* mpv 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 mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <inttypes.h>
#include <stdarg.h>
#include <assert.h>
#include <libavutil/avstring.h>
#include <libavutil/mem.h>
#include <libavutil/mathematics.h>
#include <libavutil/rational.h>
#include <libavutil/error.h>
#include <libavutil/opt.h>
#include <libavfilter/avfilter.h>
#include <libavfilter/buffersink.h>
#include <libavfilter/buffersrc.h>
#include "common/common.h"
#include "common/av_common.h"
#include "common/msg.h"
#include "audio/format.h"
#include "audio/aframe.h"
#include "video/mp_image.h"
#include "audio/fmt-conversion.h"
#include "video/fmt-conversion.h"
#include "video/hwdec.h"
#include "lavfi.h"
#if LIBAVFILTER_VERSION_MICRO < 100
#define av_buffersink_get_frame_flags(a, b, c) av_buffersink_get_frame(a, b)
#define AV_BUFFERSINK_FLAG_NO_REQUEST 0
#endif
struct lavfi {
struct mp_log *log;
char *graph_string;
struct mp_hwdec_devices *hwdec_devs;
AVFilterGraph *graph;
// Set to true once all inputs have been initialized, and the graph is
// linked.
bool initialized;
// Set if all inputs have been marked as LAVFI_WAIT (except LAVFI_EOF pads).
bool all_waiting;
// Graph is draining to undo previously sent EOF. (If a stream leaves EOF
// state, the graph needs to be recreated to "unstuck" it.)
bool draining_recover_eof;
// Graph is draining for format changes.
bool draining_new_format;
// Filter can't be put into a working state.
bool failed;
struct lavfi_pad **pads;
int num_pads;
AVFrame *tmp_frame;
};
struct lavfi_pad {
struct lavfi *main;
enum stream_type type;
enum lavfi_direction dir;
char *name; // user-given pad name
bool connected; // if false, inputs/otuputs are considered always EOF
AVFilterContext *filter;
int filter_pad;
// buffersrc or buffersink connected to filter/filter_pad
AVFilterContext *buffer;
AVRational timebase;
bool buffer_is_eof; // received/sent EOF to the buffer
// 1-frame queue (used for both input and output)
struct mp_image *pending_v;
struct mp_aframe *pending_a;
// -- dir==LAVFI_IN
bool input_needed; // filter has signaled it needs new input
bool input_waiting; // caller notified us that it will feed after a wakeup
bool input_again; // caller wants us to feed data in the next iteration
bool input_eof; // caller notified us that no input will come anymore
// used to check for format changes manually
struct mp_image *in_fmt_v;
struct mp_aframe *in_fmt_a;
// -- dir==LAVFI_OUT
bool output_needed; // caller has signaled it needs new output
bool output_eof; // last filter output was EOF
};
static void add_pad(struct lavfi *c, enum lavfi_direction dir, AVFilterInOut *item)
{
int type = -1;
enum AVMediaType avmt;
if (dir == LAVFI_IN) {
avmt = avfilter_pad_get_type(item->filter_ctx->input_pads, item->pad_idx);
} else {
avmt = avfilter_pad_get_type(item->filter_ctx->output_pads, item->pad_idx);
}
switch (avmt) {
case AVMEDIA_TYPE_VIDEO: type = STREAM_VIDEO; break;
case AVMEDIA_TYPE_AUDIO: type = STREAM_AUDIO; break;
default: abort();
}
if (!item->name) {
MP_FATAL(c, "filter pad without name label\n");
c->failed = true;
return;
}
struct lavfi_pad *p = lavfi_find_pad(c, item->name);
if (p) {
// Graph recreation case: reassociate an existing pad.
if (p->dir != dir || p->type != type) {
MP_FATAL(c, "pad '%s' changed type or direction\n", item->name);
c->failed = true;
return;
}
} else {
p = talloc_zero(c, struct lavfi_pad);
p->main = c;
p->dir = dir;
p->name = talloc_strdup(p, item->name);
p->type = type;
MP_TARRAY_APPEND(c, c->pads, c->num_pads, p);
}
p->filter = item->filter_ctx;
p->filter_pad = item->pad_idx;
}
static void add_pads(struct lavfi *c, enum lavfi_direction dir, AVFilterInOut *list)
{
for (; list; list = list->next)
add_pad(c, dir, list);
}
// Parse the user-provided filter graph, and populate the unlinked filter pads.
static void precreate_graph(struct lavfi *c)
{
assert(!c->graph);
c->graph = avfilter_graph_alloc();
if (!c->graph)
abort();
AVFilterInOut *in = NULL, *out = NULL;
if (avfilter_graph_parse2(c->graph, c->graph_string, &in, &out) < 0) {
c->graph = NULL;
MP_FATAL(c, "parsing the filter graph failed\n");
c->failed = true;
return;
}
add_pads(c, LAVFI_IN, in);
add_pads(c, LAVFI_OUT, out);
avfilter_inout_free(&in);
avfilter_inout_free(&out);
// Now check for pads which could not be reassociated.
for (int n = 0; n < c->num_pads; n++) {
struct lavfi_pad *pad = c->pads[n];
// ok, not much we can do
if (!pad->filter)
MP_FATAL(c, "filter pad '%s' can not be reconnected\n", pad->name);
}
}
static void free_graph(struct lavfi *c)
{
avfilter_graph_free(&c->graph);
for (int n = 0; n < c->num_pads; n++) {
struct lavfi_pad *pad = c->pads[n];
pad->filter = NULL;
pad->filter_pad = -1;
pad->buffer = NULL;
TA_FREEP(&pad->in_fmt_v);
TA_FREEP(&pad->in_fmt_a);
pad->buffer_is_eof = false;
pad->input_needed = false;
pad->input_waiting = false;
pad->input_again = false;
pad->input_eof = false;
pad->output_needed = false;
pad->output_eof = false;
}
c->initialized = false;
c->all_waiting = false;
c->draining_recover_eof = false;
c->draining_new_format = false;
}
static void drop_pad_data(struct lavfi_pad *pad)
{
talloc_free(pad->pending_a);
pad->pending_a = NULL;
talloc_free(pad->pending_v);
pad->pending_v = NULL;
}
static void clear_data(struct lavfi *c)
{
for (int n = 0; n < c->num_pads; n++)
drop_pad_data(c->pads[n]);
}
void lavfi_seek_reset(struct lavfi *c)
{
free_graph(c);
clear_data(c);
precreate_graph(c);
}
struct lavfi *lavfi_create(struct mp_log *log, char *graph_string)
{
struct lavfi *c = talloc_zero(NULL, struct lavfi);
c->log = log;
c->graph_string = graph_string;
c->tmp_frame = av_frame_alloc();
if (!c->tmp_frame)
abort();
precreate_graph(c);
return c;
}
void lavfi_destroy(struct lavfi *c)
{
if (!c)
return;
free_graph(c);
clear_data(c);
av_frame_free(&c->tmp_frame);
talloc_free(c);
}
const char *lavfi_get_graph(struct lavfi *c)
{
return c->graph_string;
}
struct lavfi_pad *lavfi_find_pad(struct lavfi *c, char *name)
{
for (int n = 0; n < c->num_pads; n++) {
if (strcmp(c->pads[n]->name, name) == 0)
return c->pads[n];
}
return NULL;
}
enum lavfi_direction lavfi_pad_direction(struct lavfi_pad *pad)
{
return pad->dir;
}
enum stream_type lavfi_pad_type(struct lavfi_pad *pad)
{
return pad->type;
}
void lavfi_set_connected(struct lavfi_pad *pad, bool connected)
{
pad->connected = connected;
if (!pad->connected) {
pad->output_needed = false;
drop_pad_data(pad);
}
}
bool lavfi_get_connected(struct lavfi_pad *pad)
{
return pad->connected;
}
// Ensure to send EOF to each input pad, so the graph can be drained properly.
static void send_global_eof(struct lavfi *c)
{
for (int n = 0; n < c->num_pads; n++) {
struct lavfi_pad *pad = c->pads[n];
if (!pad->buffer || pad->dir != LAVFI_IN || pad->buffer_is_eof)
continue;
if (av_buffersrc_add_frame(pad->buffer, NULL) < 0)
MP_FATAL(c, "could not send EOF to filter\n");
pad->buffer_is_eof = true;
}
}
// libavfilter allows changing some parameters on the fly, but not
// others.
static bool is_aformat_ok(struct mp_aframe *a, struct mp_aframe *b)
{
struct mp_chmap ca = {0}, cb = {0};
mp_aframe_get_chmap(a, &ca);
mp_aframe_get_chmap(b, &cb);
return mp_chmap_equals(&ca, &cb) &&
mp_aframe_get_rate(a) == mp_aframe_get_rate(b) &&
mp_aframe_get_format(a) == mp_aframe_get_format(b);
}
static bool is_vformat_ok(struct mp_image *a, struct mp_image *b)
{
return a->imgfmt == b->imgfmt &&
a->w == b->w && a->h && b->h &&
a->params.p_w == b->params.p_w && a->params.p_h == b->params.p_h;
}
static void check_format_changes(struct lavfi *c)
{
// check each pad for new input format
for (int n = 0; n < c->num_pads; n++) {
struct lavfi_pad *pad = c->pads[n];
if (!pad->buffer || pad->dir != LAVFI_IN)
continue;
if (pad->type == STREAM_AUDIO && pad->pending_a && pad->in_fmt_a) {
c->draining_new_format |= !is_aformat_ok(pad->pending_a,
pad->in_fmt_a);
}
if (pad->type == STREAM_VIDEO && pad->pending_v && pad->in_fmt_v) {
c->draining_new_format |= !is_vformat_ok(pad->pending_v,
pad->in_fmt_v);
}
}
if (c->initialized && c->draining_new_format)
send_global_eof(c);
}
// Attempt to initialize all pads. Return true if all are initialized, or
// false if more data is needed (or on error).
static bool init_pads(struct lavfi *c)
{
if (!c->graph)
goto error;
for (int n = 0; n < c->num_pads; n++) {
struct lavfi_pad *pad = c->pads[n];
if (pad->buffer)
continue;
if (!pad->filter)
goto error; // can happen if pad reassociation fails
if (pad->dir == LAVFI_OUT) {
const AVFilter *dst_filter = NULL;
if (pad->type == STREAM_AUDIO) {
dst_filter = avfilter_get_by_name("abuffersink");
} else if (pad->type == STREAM_VIDEO) {
dst_filter = avfilter_get_by_name("buffersink");
} else {
assert(0);
}
if (!dst_filter)
goto error;
char name[256];
snprintf(name, sizeof(name), "mpv_sink_%s", pad->name);
if (avfilter_graph_create_filter(&pad->buffer, dst_filter,
name, NULL, NULL, c->graph) < 0)
goto error;
if (avfilter_link(pad->filter, pad->filter_pad, pad->buffer, 0) < 0)
goto error;
} else {
TA_FREEP(&pad->in_fmt_v); // potentially cleanup previous error state
pad->input_eof |= !pad->connected;
if (pad->pending_a) {
assert(pad->type == STREAM_AUDIO);
pad->in_fmt_a = mp_aframe_new_ref(pad->pending_a);
if (!pad->in_fmt_a)
goto error;
mp_aframe_unref_data(pad->in_fmt_a);
} else if (pad->pending_v) {
assert(pad->type == STREAM_VIDEO);
pad->in_fmt_v = mp_image_new_ref(pad->pending_v);
if (!pad->in_fmt_v)
goto error;
mp_image_unref_data(pad->in_fmt_v);
} else if (pad->input_eof) {
// libavfilter makes this painful. Init it with a dummy config,
// just so we can tell it the stream is EOF.
if (pad->type == STREAM_AUDIO) {
pad->in_fmt_a = mp_aframe_create();
mp_aframe_set_format(pad->in_fmt_a, AF_FORMAT_FLOAT);
mp_aframe_set_chmap(pad->in_fmt_a,
&(struct mp_chmap)MP_CHMAP_INIT_STEREO);
mp_aframe_set_rate(pad->in_fmt_a, 48000);
} else if (pad->type == STREAM_VIDEO) {
pad->in_fmt_v = talloc_zero(NULL, struct mp_image);
mp_image_setfmt(pad->in_fmt_v, IMGFMT_420P);
mp_image_set_size(pad->in_fmt_v, 64, 64);
}
} else {
// no input data, format unknown, can't init, wait longer.
pad->input_needed = true;
return false;
}
AVBufferSrcParameters *params = av_buffersrc_parameters_alloc();
if (!params)
goto error;
char *filter_name = NULL;
if (pad->type == STREAM_AUDIO) {
params->time_base = pad->timebase =
(AVRational){1, mp_aframe_get_rate(pad->in_fmt_a)};
params->format =
af_to_avformat(mp_aframe_get_format(pad->in_fmt_a));
params->sample_rate = mp_aframe_get_rate(pad->in_fmt_a);
struct mp_chmap chmap = {0};
mp_aframe_get_chmap(pad->in_fmt_a, &chmap);
params->channel_layout = mp_chmap_to_lavc(&chmap);
filter_name = "abuffer";
} else if (pad->type == STREAM_VIDEO) {
params->time_base = pad->timebase = AV_TIME_BASE_Q;
params->format = imgfmt2pixfmt(pad->in_fmt_v->imgfmt);
params->width = pad->in_fmt_v->w;
params->height = pad->in_fmt_v->h;
params->sample_aspect_ratio.num = pad->in_fmt_v->params.p_w;
params->sample_aspect_ratio.den = pad->in_fmt_v->params.p_h;
params->hw_frames_ctx = pad->in_fmt_v->hwctx;
filter_name = "buffer";
} else {
assert(0);
}
const AVFilter *filter = avfilter_get_by_name(filter_name);
if (filter) {
char name[256];
snprintf(name, sizeof(name), "mpv_src_%s", pad->name);
pad->buffer = avfilter_graph_alloc_filter(c->graph, filter, name);
}
if (!pad->buffer) {
av_free(params);
goto error;
}
if (pad->type == STREAM_AUDIO) {
char layout[80];
snprintf(layout, sizeof(layout), "%lld",
(long long)params->channel_layout);
av_opt_set(pad->buffer, "channel_layout", layout,
AV_OPT_SEARCH_CHILDREN);
}
int ret = av_buffersrc_parameters_set(pad->buffer, params);
av_free(params);
if (ret < 0)
goto error;
if (avfilter_init_str(pad->buffer, NULL) < 0)
goto error;
if (avfilter_link(pad->buffer, 0, pad->filter, pad->filter_pad) < 0)
goto error;
}
}
return true;
error:
MP_FATAL(c, "could not initialize filter pads\n");
c->failed = true;
return false;
}
static void dump_graph(struct lavfi *c)
{
#if LIBAVFILTER_VERSION_MICRO >= 100
MP_VERBOSE(c, "Filter graph:\n");
char *s = avfilter_graph_dump(c->graph, NULL);
if (s)
MP_VERBOSE(c, "%s\n", s);
av_free(s);
#endif
}
void lavfi_pad_set_hwdec_devs(struct lavfi_pad *pad,
struct mp_hwdec_devices *hwdevs)
{
// We don't actually treat this per-pad.
pad->main->hwdec_devs = hwdevs;
}
// Initialize the graph if all inputs have formats set. If it's already
// initialized, or can't be initialized yet, do nothing.
static void init_graph(struct lavfi *c)
{
assert(!c->initialized);
if (init_pads(c)) {
if (c->hwdec_devs) {
struct mp_hwdec_ctx *hwdec = hwdec_devices_get_first(c->hwdec_devs);
for (int n = 0; n < c->graph->nb_filters; n++) {
AVFilterContext *filter = c->graph->filters[n];
if (hwdec && hwdec->av_device_ref)
filter->hw_device_ctx = av_buffer_ref(hwdec->av_device_ref);
}
}
// And here the actual libavfilter initialization happens.
if (avfilter_graph_config(c->graph, NULL) < 0) {
MP_FATAL(c, "failed to configure the filter graph\n");
free_graph(c);
c->failed = true;
return;
}
for (int n = 0; n < c->num_pads; n++) {
struct lavfi_pad *pad = c->pads[n];
if (pad->dir == LAVFI_OUT)
pad->timebase = pad->buffer->inputs[0]->time_base;
}
c->initialized = true;
dump_graph(c);
}
}
static void feed_input_pads(struct lavfi *c)
{
assert(c->initialized);
for (int n = 0; n < c->num_pads; n++) {
struct lavfi_pad *pad = c->pads[n];
if (pad->dir != LAVFI_IN)
continue;
pad->input_needed = false;
pad->input_eof |= !pad->connected;
#if LIBAVFILTER_VERSION_MICRO >= 100
if (!av_buffersrc_get_nb_failed_requests(pad->buffer))
continue;
#endif
if (c->draining_recover_eof || c->draining_new_format)
continue;
if (pad->buffer_is_eof)
continue;
AVFrame *frame = NULL;
double pts = 0;
bool eof = false;
if (pad->pending_v) {
pts = pad->pending_v->pts;
frame = mp_image_to_av_frame_and_unref(pad->pending_v);
pad->pending_v = NULL;
} else if (pad->pending_a) {
pts = mp_aframe_get_pts(pad->pending_a);
frame = mp_aframe_to_avframe_and_unref(pad->pending_a);
pad->pending_a = NULL;
} else {
if (!pad->input_eof) {
pad->input_needed = true;
continue;
}
eof = true;
}
if (!frame && !eof) {
MP_FATAL(c, "out of memory or unsupported format\n");
continue;
}
if (frame)
frame->pts = mp_pts_to_av(pts, &pad->timebase);
pad->buffer_is_eof = !frame;
if (av_buffersrc_add_frame(pad->buffer, frame) < 0)
MP_FATAL(c, "could not pass frame to filter\n");
av_frame_free(&frame);
pad->input_again = false;
pad->input_eof = eof;
pad->input_waiting = eof; // input _might_ come again in the future
}
}
static void read_output_pads(struct lavfi *c)
{
assert(c->initialized);
for (int n = 0; n < c->num_pads; n++) {
struct lavfi_pad *pad = c->pads[n];
if (pad->dir != LAVFI_OUT)
continue;
// If disconnected, read and discard everything (passively).
if (pad->connected && !pad->output_needed)
continue;
assert(pad->buffer);
assert(!pad->pending_v && !pad->pending_a);
int flags = pad->output_needed ? 0 : AV_BUFFERSINK_FLAG_NO_REQUEST;
int r = AVERROR_EOF;
if (!pad->buffer_is_eof)
r = av_buffersink_get_frame_flags(pad->buffer, c->tmp_frame, flags);
if (r >= 0) {
pad->output_needed = false;
double pts = mp_pts_from_av(c->tmp_frame->pts, &pad->timebase);
if (pad->type == STREAM_AUDIO) {
pad->pending_a = mp_aframe_from_avframe(c->tmp_frame);
if (pad->pending_a)
mp_aframe_set_pts(pad->pending_a, pts);
} else if (pad->type == STREAM_VIDEO) {
pad->pending_v = mp_image_from_av_frame(c->tmp_frame);
if (pad->pending_v)
pad->pending_v->pts = pts;
} else {
assert(0);
}
av_frame_unref(c->tmp_frame);
if (!pad->pending_v && !pad->pending_a)
MP_ERR(c, "could not use filter output\n");
pad->output_eof = false;
if (!pad->connected)
drop_pad_data(pad);
} else if (r == AVERROR(EAGAIN)) {
// We expect that libavfilter will request input on one of the
// input pads (via av_buffersrc_get_nb_failed_requests()).
pad->output_eof = false;
} else if (r == AVERROR_EOF) {
pad->output_needed = false;
pad->buffer_is_eof = true;
if (!c->draining_recover_eof && !c->draining_new_format)
pad->output_eof = true;
} else {
// Real error - ignore it.
MP_ERR(c, "error on filtering (%d)\n", r);
}
}
}
// Process filter input and outputs. Return if progress was made (then the
// caller should repeat). If it returns false, the caller should go to sleep
// (as all inputs are asleep as well and no further output can be produced).
bool lavfi_process(struct lavfi *c)
{
check_format_changes(c);
if (!c->initialized)
init_graph(c);
if (c->initialized) {
read_output_pads(c);
feed_input_pads(c);
}
bool all_waiting = true;
bool any_needs_input = false;
bool any_needs_output = false;
bool all_output_eof = true;
bool all_input_eof = true;
// Determine the graph state
for (int n = 0; n < c->num_pads; n++) {
struct lavfi_pad *pad = c->pads[n];
if (pad->dir == LAVFI_IN) {
all_waiting &= pad->input_waiting;
any_needs_input |= pad->input_needed;
all_input_eof &= pad->input_eof;
} else if (pad->dir == LAVFI_OUT) {
all_output_eof &= pad->buffer_is_eof;
any_needs_output |= pad->output_needed;
}
}
if (all_output_eof && !all_input_eof) {
free_graph(c);
precreate_graph(c);
all_waiting = false;
any_needs_input = true;
}
c->all_waiting = all_waiting;
return (any_needs_input || any_needs_output) && !all_waiting;
}
bool lavfi_has_failed(struct lavfi *c)
{
return c->failed;
}
// Request an output frame on this output pad.
// Returns req_status
static int lavfi_request_frame(struct lavfi_pad *pad)
{
assert(pad->dir == LAVFI_OUT);
if (pad->main->failed)
return DATA_EOF;
if (!(pad->pending_a || pad->pending_v)) {
pad->output_needed = true;
lavfi_process(pad->main);
}
if (pad->pending_a || pad->pending_v) {
return DATA_OK;
} else if (pad->output_eof) {
return DATA_EOF;
} else if (pad->main->all_waiting) {
return DATA_WAIT;
}
return DATA_STARVE;
}
// Try to read a new frame from an output pad. Returns one of the following:
// DATA_OK: a frame is returned
// DATA_STARVE: needs more input data
// DATA_WAIT: needs more input data, and all inputs in LAVFI_WAIT state
// DATA_EOF: no more data
int lavfi_request_frame_a(struct lavfi_pad *pad, struct mp_aframe **out_aframe)
{
int r = lavfi_request_frame(pad);
*out_aframe = pad->pending_a;
pad->pending_a = NULL;
return r;
}
// See lavfi_request_frame_a() for remarks.
int lavfi_request_frame_v(struct lavfi_pad *pad, struct mp_image **out_vframe)
{
int r = lavfi_request_frame(pad);
*out_vframe = pad->pending_v;
pad->pending_v = NULL;
return r;
}
bool lavfi_needs_input(struct lavfi_pad *pad)
{
assert(pad->dir == LAVFI_IN);
lavfi_process(pad->main);
return pad->input_needed;
}
// A filter user is supposed to call lavfi_needs_input(), and if that returns
// true, send either a new status or a frame. A status can be one of:
// DATA_STARVE: a new frame/status will come, caller will retry
// DATA_WAIT: a new frame/status will come, but caller goes to sleep
// DATA_EOF: no more input possible (in near time)
// If you have a new frame, use lavfi_send_frame_ instead.
// Calling this without lavfi_needs_input() returning true before is not
// allowed.
void lavfi_send_status(struct lavfi_pad *pad, int status)
{
assert(pad->dir == LAVFI_IN);
assert(pad->input_needed);
assert(status != DATA_OK);
assert(!pad->pending_v && !pad->pending_a);
pad->input_waiting = status == DATA_WAIT || status == DATA_EOF;
pad->input_again = status == DATA_STARVE;
pad->input_eof = status == DATA_EOF;
}
static void lavfi_sent_frame(struct lavfi_pad *pad)
{
assert(pad->dir == LAVFI_IN);
assert(pad->input_needed);
assert(pad->pending_a || pad->pending_v);
pad->input_waiting = pad->input_again = pad->input_eof = false;
pad->input_needed = false;
}
// See lavfi_send_status() for remarks.
void lavfi_send_frame_a(struct lavfi_pad *pad, struct mp_aframe *aframe)
{
assert(pad->type == STREAM_AUDIO);
assert(!pad->pending_a);
pad->pending_a = aframe;
lavfi_sent_frame(pad);
}
// See lavfi_send_status() for remarks.
void lavfi_send_frame_v(struct lavfi_pad *pad, struct mp_image *vframe)
{
assert(pad->type == STREAM_VIDEO);
assert(!pad->pending_v);
pad->pending_v = vframe;
lavfi_sent_frame(pad);
}