Libav
audio.c
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1 /*
2  * This file is part of Libav.
3  *
4  * Libav is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * Libav is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with Libav; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
20 #include "libavutil/common.h"
21 
22 #include "audio.h"
23 #include "avfilter.h"
24 #include "internal.h"
25 
27 {
28  return ff_get_audio_buffer(link->dst->outputs[0], nb_samples);
29 }
30 
32 {
33  AVFrame *frame = av_frame_alloc();
35  int ret;
36 
37  if (!frame)
38  return NULL;
39 
40  frame->nb_samples = nb_samples;
41  frame->format = link->format;
42  frame->channel_layout = link->channel_layout;
43  frame->sample_rate = link->sample_rate;
44  ret = av_frame_get_buffer(frame, 0);
45  if (ret < 0) {
46  av_frame_free(&frame);
47  return NULL;
48  }
49 
50  av_samples_set_silence(frame->extended_data, 0, nb_samples, channels,
51  link->format);
52 
53 
54  return frame;
55 }
56 
57 AVFrame *ff_get_audio_buffer(AVFilterLink *link, int nb_samples)
58 {
59  AVFrame *ret = NULL;
60 
61  if (link->dstpad->get_audio_buffer)
62  ret = link->dstpad->get_audio_buffer(link, nb_samples);
63 
64  if (!ret)
65  ret = ff_default_get_audio_buffer(link, nb_samples);
66 
67  return ret;
68 }
69 
70 #if FF_API_AVFILTERBUFFER
71 AVFilterBufferRef* avfilter_get_audio_buffer_ref_from_arrays(uint8_t **data,
72  int linesize,int perms,
73  int nb_samples,
75  uint64_t channel_layout)
76 {
77  int planes;
78  AVFilterBuffer *samples = av_mallocz(sizeof(*samples));
79  AVFilterBufferRef *samplesref = av_mallocz(sizeof(*samplesref));
80 
81  if (!samples || !samplesref)
82  goto fail;
83 
84  samplesref->buf = samples;
85  samplesref->buf->free = ff_avfilter_default_free_buffer;
86  if (!(samplesref->audio = av_mallocz(sizeof(*samplesref->audio))))
87  goto fail;
88 
89  samplesref->audio->nb_samples = nb_samples;
90  samplesref->audio->channel_layout = channel_layout;
91  samplesref->audio->planar = av_sample_fmt_is_planar(sample_fmt);
92 
93  planes = samplesref->audio->planar ? av_get_channel_layout_nb_channels(channel_layout) : 1;
94 
95  /* make sure the buffer gets read permission or it's useless for output */
96  samplesref->perms = perms | AV_PERM_READ;
97 
98  samples->refcount = 1;
99  samplesref->type = AVMEDIA_TYPE_AUDIO;
100  samplesref->format = sample_fmt;
101 
102  memcpy(samples->data, data,
103  FFMIN(FF_ARRAY_ELEMS(samples->data), planes)*sizeof(samples->data[0]));
104  memcpy(samplesref->data, samples->data, sizeof(samples->data));
105 
106  samples->linesize[0] = samplesref->linesize[0] = linesize;
107 
108  if (planes > FF_ARRAY_ELEMS(samples->data)) {
109  samples-> extended_data = av_mallocz(sizeof(*samples->extended_data) *
110  planes);
111  samplesref->extended_data = av_mallocz(sizeof(*samplesref->extended_data) *
112  planes);
113 
114  if (!samples->extended_data || !samplesref->extended_data)
115  goto fail;
116 
117  memcpy(samples-> extended_data, data, sizeof(*data)*planes);
118  memcpy(samplesref->extended_data, data, sizeof(*data)*planes);
119  } else {
120  samples->extended_data = samples->data;
121  samplesref->extended_data = samplesref->data;
122  }
123 
124  samplesref->pts = AV_NOPTS_VALUE;
125 
126  return samplesref;
127 
128 fail:
129  if (samples && samples->extended_data != samples->data)
130  av_freep(&samples->extended_data);
131  if (samplesref) {
132  av_freep(&samplesref->audio);
133  if (samplesref->extended_data != samplesref->data)
134  av_freep(&samplesref->extended_data);
135  }
136  av_freep(&samplesref);
137  av_freep(&samples);
138  return NULL;
139 }
140 #endif