| /* |
| * ALSA input and output |
| * Copyright (c) 2007 Luca Abeni ( lucabe72 email it ) |
| * Copyright (c) 2007 Benoit Fouet ( benoit fouet free fr ) |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| /** |
| * @file libavdevice/alsa-audio.h |
| * ALSA input and output: definitions and structures |
| * @author Luca Abeni ( lucabe72 email it ) |
| * @author Benoit Fouet ( benoit fouet free fr ) |
| */ |
| |
| #ifndef AVDEVICE_ALSA_AUDIO_H |
| #define AVDEVICE_ALSA_AUDIO_H |
| |
| #include <alsa/asoundlib.h> |
| #include "config.h" |
| #include "libavformat/avformat.h" |
| |
| /* XXX: we make the assumption that the soundcard accepts this format */ |
| /* XXX: find better solution with "preinit" method, needed also in |
| other formats */ |
| #ifdef WORDS_BIGENDIAN |
| #define DEFAULT_CODEC_ID CODEC_ID_PCM_S16BE |
| #else |
| #define DEFAULT_CODEC_ID CODEC_ID_PCM_S16LE |
| #endif |
| |
| typedef struct { |
| snd_pcm_t *h; |
| int frame_size; ///< preferred size for reads and writes |
| int period_size; ///< bytes per sample * channels |
| } AlsaData; |
| |
| /** |
| * Opens an ALSA PCM. |
| * |
| * @param s media file handle |
| * @param mode either SND_PCM_STREAM_CAPTURE or SND_PCM_STREAM_PLAYBACK |
| * @param sample_rate in: requested sample rate; |
| * out: actually selected sample rate |
| * @param channels number of channels |
| * @param codec_id in: requested CodecID or CODEC_ID_NONE; |
| * out: actually selected CodecID, changed only if |
| * CODEC_ID_NONE was requested |
| * |
| * @return 0 if OK, AVERROR_xxx on error |
| */ |
| int ff_alsa_open(AVFormatContext *s, int mode, unsigned int *sample_rate, |
| int channels, int *codec_id); |
| |
| /** |
| * Closes the ALSA PCM. |
| * |
| * @param s1 media file handle |
| * |
| * @return 0 |
| */ |
| int ff_alsa_close(AVFormatContext *s1); |
| |
| /** |
| * Tries to recover from ALSA buffer underrun. |
| * |
| * @param s1 media file handle |
| * @param err error code reported by the previous ALSA call |
| * |
| * @return 0 if OK, AVERROR_xxx on error |
| */ |
| int ff_alsa_xrun_recover(AVFormatContext *s1, int err); |
| |
| #endif /* AVDEVICE_ALSA_AUDIO_H */ |