ffmpeg/fftools/sync_queue.h

119 lines
3.8 KiB
C

/*
* 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
*/
#ifndef FFTOOLS_SYNC_QUEUE_H
#define FFTOOLS_SYNC_QUEUE_H
#include <stdint.h>
#include "libavcodec/packet.h"
#include "libavutil/frame.h"
enum SyncQueueType {
SYNC_QUEUE_PACKETS,
SYNC_QUEUE_FRAMES,
};
typedef union SyncQueueFrame {
AVFrame *f;
AVPacket *p;
} SyncQueueFrame;
#define SQFRAME(frame) ((SyncQueueFrame){ .f = (frame) })
#define SQPKT(pkt) ((SyncQueueFrame){ .p = (pkt) })
/**
* A sync queue provides timestamp synchronization between multiple streams.
* Some of these streams are marked as "limiting", then the queue ensures no
* stream gets ahead of any of the limiting streams.
*/
typedef struct SyncQueue SyncQueue;
/**
* Allocate a sync queue of the given type.
*
* @param buf_size_us maximum duration that will be buffered in microseconds
*/
SyncQueue *sq_alloc(enum SyncQueueType type, int64_t buf_size_us);
void sq_free(SyncQueue **sq);
/**
* Add a new stream to the sync queue.
*
* @param limiting whether the stream is limiting, i.e. no other stream can be
* longer than this one
* @return
* - a non-negative stream index on success
* - a negative error code on error
*/
int sq_add_stream(SyncQueue *sq, int limiting);
/**
* Limit the number of output frames for stream with index stream_idx
* to max_frames.
*/
void sq_limit_frames(SyncQueue *sq, unsigned int stream_idx,
uint64_t max_frames);
/**
* Set a constant output audio frame size, in samples. Can only be used with
* SYNC_QUEUE_FRAMES queues and audio streams.
*
* All output frames will have exactly frame_samples audio samples, except
* possibly for the last one, which may have fewer.
*/
void sq_frame_samples(SyncQueue *sq, unsigned int stream_idx,
int frame_samples);
/**
* Submit a frame for the stream with index stream_idx.
*
* On success, the sync queue takes ownership of the frame and will reset the
* contents of the supplied frame. On failure, the frame remains owned by the
* caller.
*
* Sending a frame with NULL contents marks the stream as finished.
*
* @return
* - 0 on success
* - AVERROR_EOF when no more frames should be submitted for this stream
* - another a negative error code on failure
*/
int sq_send(SyncQueue *sq, unsigned int stream_idx, SyncQueueFrame frame);
/**
* Read a frame from the queue.
*
* @param stream_idx index of the stream to read a frame for. May be -1, then
* try to read a frame from any stream that is ready for
* output.
* @param frame output frame will be written here on success. The frame is owned
* by the caller.
*
* @return
* - a non-negative index of the stream to which the returned frame belongs
* - AVERROR(EAGAIN) when more frames need to be submitted to the queue
* - AVERROR_EOF when no more frames will be available for this stream (for any
* stream if stream_idx is -1)
* - another negative error code on failure
*/
int sq_receive(SyncQueue *sq, int stream_idx, SyncQueueFrame frame);
#endif // FFTOOLS_SYNC_QUEUE_H