/* * Audio FIFO * Copyright (c) 2012 Justin Ruggles <justin.ruggles@gmail.com> * * This file is part of Libav. * * Libav 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. * * Libav 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 Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * Audio FIFO Buffer */ #ifndef AVUTIL_AUDIO_FIFO_H #define AVUTIL_AUDIO_FIFO_H #include "avutil.h" #include "fifo.h" #include "samplefmt.h" /** * @addtogroup lavu_audio * @{ */ /** * Context for an Audio FIFO Buffer. * * - Operates at the sample level rather than the byte level. * - Supports multiple channels with either planar or packed sample format. * - Automatic reallocation when writing to a full buffer. */ typedef struct AVAudioFifo AVAudioFifo; /** * Free an AVAudioFifo. * * @param af AVAudioFifo to free */ void av_audio_fifo_free(AVAudioFifo *af); /** * Allocate an AVAudioFifo. * * @param sample_fmt sample format * @param channels number of channels * @param nb_samples initial allocation size, in samples * @return newly allocated AVAudioFifo, or NULL on error */ AVAudioFifo *av_audio_fifo_alloc(enum AVSampleFormat sample_fmt, int channels, int nb_samples); /** * Reallocate an AVAudioFifo. * * @param af AVAudioFifo to reallocate * @param nb_samples new allocation size, in samples * @return 0 if OK, or negative AVERROR code on failure */ int av_audio_fifo_realloc(AVAudioFifo *af, int nb_samples); /** * Write data to an AVAudioFifo. * * The AVAudioFifo will be reallocated automatically if the available space * is less than nb_samples. * * @see enum AVSampleFormat * The documentation for AVSampleFormat describes the data layout. * * @param af AVAudioFifo to write to * @param data audio data plane pointers * @param nb_samples number of samples to write * @return number of samples actually written, or negative AVERROR * code on failure. */ int av_audio_fifo_write(AVAudioFifo *af, void **data, int nb_samples); /** * Read data from an AVAudioFifo. * * @see enum AVSampleFormat * The documentation for AVSampleFormat describes the data layout. * * @param af AVAudioFifo to read from * @param data audio data plane pointers * @param nb_samples number of samples to read * @return number of samples actually read, or negative AVERROR code * on failure. */ int av_audio_fifo_read(AVAudioFifo *af, void **data, int nb_samples); /** * Drain data from an AVAudioFifo. * * Removes the data without reading it. * * @param af AVAudioFifo to drain * @param nb_samples number of samples to drain * @return 0 if OK, or negative AVERROR code on failure */ int av_audio_fifo_drain(AVAudioFifo *af, int nb_samples); /** * Reset the AVAudioFifo buffer. * * This empties all data in the buffer. * * @param af AVAudioFifo to reset */ void av_audio_fifo_reset(AVAudioFifo *af); /** * Get the current number of samples in the AVAudioFifo available for reading. * * @param af the AVAudioFifo to query * @return number of samples available for reading */ int av_audio_fifo_size(AVAudioFifo *af); /** * Get the current number of samples in the AVAudioFifo available for writing. * * @param af the AVAudioFifo to query * @return number of samples available for writing */ int av_audio_fifo_space(AVAudioFifo *af); /** * @} */ #endif /* AVUTIL_AUDIO_FIFO_H */