/*

 * 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 */