Subversion Repositories Kolibri OS

Rev

Go to most recent revision | Blame | Last modification | View Log | RSS feed

  1. /*
  2.  * ALSA input and output
  3.  * Copyright (c) 2007 Luca Abeni ( lucabe72 email it )
  4.  * Copyright (c) 2007 Benoit Fouet ( benoit fouet free fr )
  5.  *
  6.  * This file is part of FFmpeg.
  7.  *
  8.  * FFmpeg is free software; you can redistribute it and/or
  9.  * modify it under the terms of the GNU Lesser General Public
  10.  * License as published by the Free Software Foundation; either
  11.  * version 2.1 of the License, or (at your option) any later version.
  12.  *
  13.  * FFmpeg is distributed in the hope that it will be useful,
  14.  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16.  * Lesser General Public License for more details.
  17.  *
  18.  * You should have received a copy of the GNU Lesser General Public
  19.  * License along with FFmpeg; if not, write to the Free Software
  20.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21.  */
  22.  
  23. /**
  24.  * @file
  25.  * ALSA input and output: definitions and structures
  26.  * @author Luca Abeni ( lucabe72 email it )
  27.  * @author Benoit Fouet ( benoit fouet free fr )
  28.  */
  29.  
  30. #ifndef AVDEVICE_ALSA_AUDIO_H
  31. #define AVDEVICE_ALSA_AUDIO_H
  32.  
  33. #include <alsa/asoundlib.h>
  34. #include "config.h"
  35. #include "libavutil/log.h"
  36. #include "timefilter.h"
  37. #include "avdevice.h"
  38.  
  39. /* XXX: we make the assumption that the soundcard accepts this format */
  40. /* XXX: find better solution with "preinit" method, needed also in
  41.         other formats */
  42. #define DEFAULT_CODEC_ID AV_NE(AV_CODEC_ID_PCM_S16BE, AV_CODEC_ID_PCM_S16LE)
  43.  
  44. typedef void (*ff_reorder_func)(const void *, void *, int);
  45.  
  46. #define ALSA_BUFFER_SIZE_MAX 65536
  47.  
  48. typedef struct AlsaData {
  49.     AVClass *class;
  50.     snd_pcm_t *h;
  51.     int frame_size;  ///< bytes per sample * channels
  52.     int period_size; ///< preferred size for reads and writes, in frames
  53.     int sample_rate; ///< sample rate set by user
  54.     int channels;    ///< number of channels set by user
  55.     int last_period;
  56.     TimeFilter *timefilter;
  57.     void (*reorder_func)(const void *, void *, int);
  58.     void *reorder_buf;
  59.     int reorder_buf_size; ///< in frames
  60. } AlsaData;
  61.  
  62. /**
  63.  * Open an ALSA PCM.
  64.  *
  65.  * @param s media file handle
  66.  * @param mode either SND_PCM_STREAM_CAPTURE or SND_PCM_STREAM_PLAYBACK
  67.  * @param sample_rate in: requested sample rate;
  68.  *                    out: actually selected sample rate
  69.  * @param channels number of channels
  70.  * @param codec_id in: requested AVCodecID or AV_CODEC_ID_NONE;
  71.  *                 out: actually selected AVCodecID, changed only if
  72.  *                 AV_CODEC_ID_NONE was requested
  73.  *
  74.  * @return 0 if OK, AVERROR_xxx on error
  75.  */
  76. int ff_alsa_open(AVFormatContext *s, snd_pcm_stream_t mode,
  77.                  unsigned int *sample_rate,
  78.                  int channels, enum AVCodecID *codec_id);
  79.  
  80. /**
  81.  * Close the ALSA PCM.
  82.  *
  83.  * @param s1 media file handle
  84.  *
  85.  * @return 0
  86.  */
  87. int ff_alsa_close(AVFormatContext *s1);
  88.  
  89. /**
  90.  * Try to recover from ALSA buffer underrun.
  91.  *
  92.  * @param s1 media file handle
  93.  * @param err error code reported by the previous ALSA call
  94.  *
  95.  * @return 0 if OK, AVERROR_xxx on error
  96.  */
  97. int ff_alsa_xrun_recover(AVFormatContext *s1, int err);
  98.  
  99. int ff_alsa_extend_reorder_buf(AlsaData *s, int size);
  100.  
  101. #endif /* AVDEVICE_ALSA_AUDIO_H */
  102.