Imported Debian version 2.5.2~trusty
[deb_ffmpeg.git] / ffmpeg / libavdevice / oss_audio_dec.c
1 /*
2 * Linux audio play interface
3 * Copyright (c) 2000, 2001 Fabrice Bellard
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
9 * License 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 GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #include "config.h"
23
24 #include <stdint.h>
25
26 #if HAVE_SOUNDCARD_H
27 #include <soundcard.h>
28 #else
29 #include <sys/soundcard.h>
30 #endif
31
32 #if HAVE_UNISTD_H
33 #include <unistd.h>
34 #endif
35 #include <fcntl.h>
36 #include <sys/ioctl.h>
37
38 #include "libavutil/internal.h"
39 #include "libavutil/opt.h"
40 #include "libavutil/time.h"
41
42 #include "libavcodec/avcodec.h"
43
44 #include "avdevice.h"
45 #include "libavformat/internal.h"
46
47 #include "oss_audio.h"
48
49 static int audio_read_header(AVFormatContext *s1)
50 {
51 OSSAudioData *s = s1->priv_data;
52 AVStream *st;
53 int ret;
54
55 st = avformat_new_stream(s1, NULL);
56 if (!st) {
57 return AVERROR(ENOMEM);
58 }
59
60 ret = ff_oss_audio_open(s1, 0, s1->filename);
61 if (ret < 0) {
62 return AVERROR(EIO);
63 }
64
65 /* take real parameters */
66 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
67 st->codec->codec_id = s->codec_id;
68 st->codec->sample_rate = s->sample_rate;
69 st->codec->channels = s->channels;
70
71 avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
72 return 0;
73 }
74
75 static int audio_read_packet(AVFormatContext *s1, AVPacket *pkt)
76 {
77 OSSAudioData *s = s1->priv_data;
78 int ret, bdelay;
79 int64_t cur_time;
80 struct audio_buf_info abufi;
81
82 if ((ret=av_new_packet(pkt, s->frame_size)) < 0)
83 return ret;
84
85 ret = read(s->fd, pkt->data, pkt->size);
86 if (ret <= 0){
87 av_free_packet(pkt);
88 pkt->size = 0;
89 if (ret<0) return AVERROR(errno);
90 else return AVERROR_EOF;
91 }
92 pkt->size = ret;
93
94 /* compute pts of the start of the packet */
95 cur_time = av_gettime();
96 bdelay = ret;
97 if (ioctl(s->fd, SNDCTL_DSP_GETISPACE, &abufi) == 0) {
98 bdelay += abufi.bytes;
99 }
100 /* subtract time represented by the number of bytes in the audio fifo */
101 cur_time -= (bdelay * 1000000LL) / (s->sample_rate * s->channels);
102
103 /* convert to wanted units */
104 pkt->pts = cur_time;
105
106 if (s->flip_left && s->channels == 2) {
107 int i;
108 short *p = (short *) pkt->data;
109
110 for (i = 0; i < ret; i += 4) {
111 *p = ~*p;
112 p += 2;
113 }
114 }
115 return 0;
116 }
117
118 static int audio_read_close(AVFormatContext *s1)
119 {
120 OSSAudioData *s = s1->priv_data;
121
122 ff_oss_audio_close(s);
123 return 0;
124 }
125
126 static const AVOption options[] = {
127 { "sample_rate", "", offsetof(OSSAudioData, sample_rate), AV_OPT_TYPE_INT, {.i64 = 48000}, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
128 { "channels", "", offsetof(OSSAudioData, channels), AV_OPT_TYPE_INT, {.i64 = 2}, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
129 { NULL },
130 };
131
132 static const AVClass oss_demuxer_class = {
133 .class_name = "OSS demuxer",
134 .item_name = av_default_item_name,
135 .option = options,
136 .version = LIBAVUTIL_VERSION_INT,
137 .category = AV_CLASS_CATEGORY_DEVICE_AUDIO_INPUT,
138 };
139
140 AVInputFormat ff_oss_demuxer = {
141 .name = "oss",
142 .long_name = NULL_IF_CONFIG_SMALL("OSS (Open Sound System) capture"),
143 .priv_data_size = sizeof(OSSAudioData),
144 .read_header = audio_read_header,
145 .read_packet = audio_read_packet,
146 .read_close = audio_read_close,
147 .flags = AVFMT_NOFILE,
148 .priv_class = &oss_demuxer_class,
149 };