path: root/libavfilter/framequeue.c (plain)
blob: 26bfa499675cb006fb20c1974f57db18865ffff4

1	/*
2	* Generic frame queue
3	* Copyright (c) 2016 Nicolas George
4	*
5	* This file is part of FFmpeg.
6	*
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.
11	*
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.
16	*
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
20	*/
21
22	#include "libavutil/avassert.h"
23	#include "framequeue.h"
24
25	static inline FFFrameBucket *bucket(FFFrameQueue *fq, size_t idx)
26	{
27	return &fq->queue[(fq->tail + idx) & (fq->allocated - 1)];
28	}
29
30	void ff_framequeue_global_init(FFFrameQueueGlobal *fqg)
31	{
32	}
33
34	static void check_consistency(FFFrameQueue *fq)
35	{
36	#if defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
37	uint64_t nb_samples = 0;
38	size_t i;
39
40	av_assert0(fq->queued == fq->total_frames_head - fq->total_frames_tail);
41	for (i = 0; i < fq->queued; i++)
42	nb_samples += bucket(fq, i)->frame->nb_samples;
43	av_assert0(nb_samples == fq->total_samples_head - fq->total_samples_tail);
44	#endif
45	}
46
47	void ff_framequeue_init(FFFrameQueue *fq, FFFrameQueueGlobal *fqg)
48	{
49	fq->queue = &fq->first_bucket;
50	fq->allocated = 1;
51	}
52
53	void ff_framequeue_free(FFFrameQueue *fq)
54	{
55	while (fq->queued) {
56	AVFrame *frame = ff_framequeue_take(fq);
57	av_frame_free(&frame);
58	}
59	if (fq->queue != &fq->first_bucket)
60	av_freep(&fq->queue);
61	}
62
63	int ff_framequeue_add(FFFrameQueue *fq, AVFrame *frame)
64	{
65	FFFrameBucket *b;
66
67	check_consistency(fq);
68	if (fq->queued == fq->allocated) {
69	if (fq->allocated == 1) {
70	size_t na = 8;
71	FFFrameBucket *nq = av_realloc_array(NULL, na, sizeof(*nq));
72	if (!nq)
73	return AVERROR(ENOMEM);
74	nq[0] = fq->queue[0];
75	fq->queue = nq;
76	fq->allocated = na;
77	} else {
78	size_t na = fq->allocated << 1;
79	FFFrameBucket *nq = av_realloc_array(fq->queue, na, sizeof(*nq));
80	if (!nq)
81	return AVERROR(ENOMEM);
82	if (fq->tail + fq->queued > fq->allocated)
83	memmove(nq + fq->allocated, nq,
84	(fq->tail + fq->queued - fq->allocated) * sizeof(*nq));
85	fq->queue = nq;
86	fq->allocated = na;
87	}
88	}
89	b = bucket(fq, fq->queued);
90	b->frame = frame;
91	fq->queued++;
92	fq->total_frames_head++;
93	fq->total_samples_head += frame->nb_samples;
94	check_consistency(fq);
95	return 0;
96	}
97
98	AVFrame *ff_framequeue_take(FFFrameQueue *fq)
99	{
100	FFFrameBucket *b;
101
102	check_consistency(fq);
103	av_assert1(fq->queued);
104	b = bucket(fq, 0);
105	fq->queued--;
106	fq->tail++;
107	fq->tail &= fq->allocated - 1;
108	fq->total_frames_tail++;
109	fq->total_samples_tail += b->frame->nb_samples;
110	check_consistency(fq);
111	return b->frame;
112	}
113
114	AVFrame *ff_framequeue_peek(FFFrameQueue *fq, size_t idx)
115	{
116	FFFrameBucket *b;
117
118	check_consistency(fq);
119	av_assert1(idx < fq->queued);
120	b = bucket(fq, idx);
121	check_consistency(fq);
122	return b->frame;
123	}
124
125	void ff_framequeue_skip_samples(FFFrameQueue *fq, size_t samples, AVRational time_base)
126	{
127	FFFrameBucket *b;
128	size_t bytes;
129	int planar, planes, i;
130
131	check_consistency(fq);
132	av_assert1(fq->queued);
133	b = bucket(fq, 0);
134	av_assert1(samples < b->frame->nb_samples);
135	planar = av_sample_fmt_is_planar(b->frame->format);
136	planes = planar ? b->frame->channels : 1;
137	bytes = samples * av_get_bytes_per_sample(b->frame->format);
138	if (!planar)
139	bytes *= b->frame->channels;
140	if (b->frame->pts != AV_NOPTS_VALUE)
141	b->frame->pts += av_rescale_q(samples, av_make_q(1, b->frame->sample_rate), time_base);
142	b->frame->nb_samples -= samples;
143	b->frame->linesize[0] -= bytes;
144	for (i = 0; i < planes; i++)
145	b->frame->extended_data[i] += bytes;
146	for (i = 0; i < planes && i < AV_NUM_DATA_POINTERS; i++)
147	b->frame->data[i] = b->frame->extended_data[i];
148	fq->total_samples_tail += samples;
149	ff_framequeue_update_peeked(fq, 0);
150	}
151