3 * Copyright (c) 2016 Nicolas George
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public License
9 * as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public License
18 * along with FFmpeg; if not, write to the Free Software Foundation, Inc.,
19 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 #ifndef AVFILTER_FRAMEQUEUE_H
23 #define AVFILTER_FRAMEQUEUE_H
26 * FFFrameQueue: simple AVFrame queue API
28 * Note: this API is not thread-safe. Concurrent access to the same queue
29 * must be protected by a mutex or any synchronization mechanism.
32 #include "libavutil/frame.h"
34 typedef struct FFFrameBucket {
39 * Structure to hold global options and statistics for frame queues.
41 * This structure is intended to allow implementing global control of the
42 * frame queues, including memory consumption caps.
44 * It is currently empty.
46 typedef struct FFFrameQueueGlobal {
47 char dummy; /* C does not allow empty structs */
51 * Queue of AVFrame pointers.
53 typedef struct FFFrameQueue {
56 * Array of allocated buckets, used as a circular buffer.
61 * Size of the array of buckets.
67 * It is the index in the array of the next frame to take.
72 * Number of currently queued frames.
77 * Pre-allocated bucket for queues of size 1.
79 FFFrameBucket first_bucket;
82 * Total number of frames entered in the queue.
84 uint64_t total_frames_head;
87 * Total number of frames dequeued from the queue.
88 * queued = total_frames_head - total_frames_tail
90 uint64_t total_frames_tail;
93 * Total number of samples entered in the queue.
95 uint64_t total_samples_head;
98 * Total number of samples dequeued from the queue.
99 * queued_samples = total_samples_head - total_samples_tail
101 uint64_t total_samples_tail;
104 * Indicate that samples are skipped
111 * Init a global structure.
113 void ff_framequeue_global_init(FFFrameQueueGlobal *fqg);
116 * Init a frame queue and attach it to a global structure.
118 void ff_framequeue_init(FFFrameQueue *fq, FFFrameQueueGlobal *fqg);
121 * Free the queue and all queued frames.
123 void ff_framequeue_free(FFFrameQueue *fq);
127 * @return >=0 or an AVERROR code.
129 int ff_framequeue_add(FFFrameQueue *fq, AVFrame *frame);
132 * Take the first frame in the queue.
133 * Must not be used with empty queues.
135 AVFrame *ff_framequeue_take(FFFrameQueue *fq);
138 * Access a frame in the queue, without removing it.
139 * The first frame is numbered 0; the designated frame must exist.
141 AVFrame *ff_framequeue_peek(FFFrameQueue *fq, size_t idx);
144 * Get the number of queued frames.
146 static inline size_t ff_framequeue_queued_frames(const FFFrameQueue *fq)
152 * Get the number of queued samples.
154 static inline uint64_t ff_framequeue_queued_samples(const FFFrameQueue *fq)
156 return fq->total_samples_head - fq->total_samples_tail;
160 * Update the statistics after a frame accessed using ff_framequeue_peek()
162 * Currently used only as a marker.
164 static inline void ff_framequeue_update_peeked(FFFrameQueue *fq, size_t idx)
169 * Skip samples from the first frame in the queue.
171 * This function must be used when the first frame was accessed using
172 * ff_framequeue_peek() and samples were consumed from it.
173 * It adapts the data pointers and timestamps of the head frame to account
174 * for the skipped samples.
176 void ff_framequeue_skip_samples(FFFrameQueue *fq, size_t samples, AVRational time_base);
178 #endif /* AVFILTER_FRAMEQUEUE_H */