3 * Copyright (c) 2012 Justin Ruggles
5 * This file is part of Libav.
7 * Libav is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * Libav 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 GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 #include "libavutil/common.h"
23 #include "libavutil/mathematics.h"
25 #include "audio_frame_queue.h"
27 void ff_af_queue_init(AVCodecContext *avctx, AudioFrameQueue *afq)
30 afq->next_pts = AV_NOPTS_VALUE;
31 afq->remaining_delay = avctx->delay;
32 afq->remaining_samples = avctx->delay;
33 afq->frame_queue = NULL;
36 static void delete_next_frame(AudioFrameQueue *afq)
38 AudioFrame *f = afq->frame_queue;
40 afq->frame_queue = f->next;
46 void ff_af_queue_close(AudioFrameQueue *afq)
48 /* remove/free any remaining frames */
49 while (afq->frame_queue)
50 delete_next_frame(afq);
51 memset(afq, 0, sizeof(*afq));
54 int ff_af_queue_add(AudioFrameQueue *afq, const AVFrame *f)
56 AudioFrame *new_frame;
57 AudioFrame *queue_end = afq->frame_queue;
59 /* find the end of the queue */
60 while (queue_end && queue_end->next)
61 queue_end = queue_end->next;
63 /* allocate new frame queue entry */
64 if (!(new_frame = av_malloc(sizeof(*new_frame))))
65 return AVERROR(ENOMEM);
67 /* get frame parameters */
68 new_frame->next = NULL;
69 new_frame->duration = f->nb_samples;
70 if (f->pts != AV_NOPTS_VALUE) {
71 new_frame->pts = av_rescale_q(f->pts,
72 afq->avctx->time_base,
73 (AVRational){ 1, afq->avctx->sample_rate });
74 afq->next_pts = new_frame->pts + new_frame->duration;
76 new_frame->pts = AV_NOPTS_VALUE;
77 afq->next_pts = AV_NOPTS_VALUE;
80 /* add new frame to the end of the queue */
82 afq->frame_queue = new_frame;
84 queue_end->next = new_frame;
86 /* add frame sample count */
87 afq->remaining_samples += f->nb_samples;
90 ff_af_queue_log_state(afq);
96 void ff_af_queue_remove(AudioFrameQueue *afq, int nb_samples, int64_t *pts,
99 int64_t out_pts = AV_NOPTS_VALUE;
100 int removed_samples = 0;
103 ff_af_queue_log_state(afq);
106 /* get output pts from the next frame or generated pts */
107 if (afq->frame_queue) {
108 if (afq->frame_queue->pts != AV_NOPTS_VALUE)
109 out_pts = afq->frame_queue->pts - afq->remaining_delay;
111 if (afq->next_pts != AV_NOPTS_VALUE)
112 out_pts = afq->next_pts - afq->remaining_delay;
115 if (out_pts != AV_NOPTS_VALUE)
116 *pts = ff_samples_to_time_base(afq->avctx, out_pts);
118 *pts = AV_NOPTS_VALUE;
121 /* if the delay is larger than the packet duration, we use up delay samples
122 for the output packet and leave all frames in the queue */
123 if (afq->remaining_delay >= nb_samples) {
124 removed_samples += nb_samples;
125 afq->remaining_delay -= nb_samples;
127 /* remove frames from the queue until we have enough to cover the
128 requested number of samples or until the queue is empty */
129 while (removed_samples < nb_samples && afq->frame_queue) {
130 removed_samples += afq->frame_queue->duration;
131 delete_next_frame(afq);
133 afq->remaining_samples -= removed_samples;
135 /* if there are no frames left and we have room for more samples, use
136 any remaining delay samples */
137 if (removed_samples < nb_samples && afq->remaining_samples > 0) {
138 int add_samples = FFMIN(afq->remaining_samples,
139 nb_samples - removed_samples);
140 removed_samples += add_samples;
141 afq->remaining_samples -= add_samples;
143 if (removed_samples > nb_samples)
144 av_log(afq->avctx, AV_LOG_WARNING, "frame_size is too large\n");
146 *duration = ff_samples_to_time_base(afq->avctx, removed_samples);
149 void ff_af_queue_log_state(AudioFrameQueue *afq)
152 av_log(afq->avctx, AV_LOG_DEBUG, "remaining delay = %d\n",
153 afq->remaining_delay);
154 av_log(afq->avctx, AV_LOG_DEBUG, "remaining samples = %d\n",
155 afq->remaining_samples);
156 av_log(afq->avctx, AV_LOG_DEBUG, "frames:\n");
157 f = afq->frame_queue;
159 av_log(afq->avctx, AV_LOG_DEBUG, " [ pts=%9"PRId64" duration=%d ]\n",
160 f->pts, f->duration);