vlc_aout.h

mips版本的VLC视频服务器

/*****************************************************************************
 * audio_output.h : audio output interface
 *****************************************************************************
 * Copyright (C) 2002-2005 the VideoLAN team
 * $Id: 98a2a584749596f7c9cc444909fbac4167a1a479 $
 *
 * Authors: Christophe Massiot <[e-mail]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
 *****************************************************************************/

#ifndef VLC_AOUT_H
#define VLC_AOUT_H 1

/**
 * \file
 * This file defines functions, structures and macros for audio output object
 */

# ifdef __cplusplus
extern "C" {
# endif

#include "vlc_es.h"

#define AOUT_FMTS_IDENTICAL( p_first, p_second ) (                          \
    ((p_first)->i_format == (p_second)->i_format)                           \
      && ((p_first)->i_rate == (p_second)->i_rate)                          \
      && ((p_first)->i_physical_channels == (p_second)->i_physical_channels)\
      && ((p_first)->i_original_channels == (p_second)->i_original_channels) )

/* Check if i_rate == i_rate and i_channels == i_channels */
#define AOUT_FMTS_SIMILAR( p_first, p_second ) (                            \
    ((p_first)->i_rate == (p_second)->i_rate)                               \
      && ((p_first)->i_physical_channels == (p_second)->i_physical_channels)\
      && ((p_first)->i_original_channels == (p_second)->i_original_channels) )

#ifdef WORDS_BIGENDIAN
#   define AOUT_FMT_S16_NE VLC_FOURCC('s','1','6','b')
#   define AOUT_FMT_U16_NE VLC_FOURCC('u','1','6','b')
#   define AOUT_FMT_S24_NE VLC_FOURCC('s','2','4','b')
#   define AOUT_FMT_S32_NE VLC_FOURCC('s','3','2','b')
#   define AOUT_FMT_SPDIF_NE VLC_FOURCC('s','p','d','b')
#else
#   define AOUT_FMT_S16_NE VLC_FOURCC('s','1','6','l')
#   define AOUT_FMT_U16_NE VLC_FOURCC('u','1','6','l')
#   define AOUT_FMT_S24_NE VLC_FOURCC('s','2','4','l')
#   define AOUT_FMT_S32_NE VLC_FOURCC('s','3','2','l')
#   define AOUT_FMT_SPDIF_NE VLC_FOURCC('s','p','d','i')
#endif

#define AOUT_FMT_NON_LINEAR( p_format )                                    \
    ( ((p_format)->i_format == VLC_FOURCC('s','p','d','i'))                \
       || ((p_format)->i_format == VLC_FOURCC('s','p','d','b'))            \
       || ((p_format)->i_format == VLC_FOURCC('a','5','2',' '))            \
       || ((p_format)->i_format == VLC_FOURCC('d','t','s',' ')) )

/* This is heavily borrowed from libmad, by Robert Leslie <[e-mail]> */
/*
 * Fixed-point format: 0xABBBBBBB
 * A == whole part      (sign + 3 bits)
 * B == fractional part (28 bits)
 *
 * Values are signed two's complement, so the effective range is:
 * 0x80000000 to 0x7fffffff
 *       -8.0 to +7.9999999962747097015380859375
 *
 * The smallest representable value is:
 * 0x00000001 == 0.0000000037252902984619140625 (i.e. about 3.725e-9)
 *
 * 28 bits of fractional accuracy represent about
 * 8.6 digits of decimal accuracy.
 *
 * Fixed-point numbers can be added or subtracted as normal
 * integers, but multiplication requires shifting the 64-bit result
 * from 56 fractional bits back to 28 (and rounding.)
 */
typedef int32_t vlc_fixed_t;
#define FIXED32_FRACBITS 28
#define FIXED32_MIN ((vlc_fixed_t) -0x80000000L)
#define FIXED32_MAX ((vlc_fixed_t) +0x7fffffffL)
#define FIXED32_ONE ((vlc_fixed_t) 0x10000000)

/*
 * Channels descriptions
 */

/* Values available for physical and original channels */
#define AOUT_CHAN_CENTER            0x1
#define AOUT_CHAN_LEFT              0x2
#define AOUT_CHAN_RIGHT             0x4
#define AOUT_CHAN_REARCENTER        0x10
#define AOUT_CHAN_REARLEFT          0x20
#define AOUT_CHAN_REARRIGHT         0x40
#define AOUT_CHAN_MIDDLELEFT        0x100
#define AOUT_CHAN_MIDDLERIGHT       0x200
#define AOUT_CHAN_LFE               0x1000

/* Values available for original channels only */
#define AOUT_CHAN_DOLBYSTEREO       0x10000
#define AOUT_CHAN_DUALMONO          0x20000
#define AOUT_CHAN_REVERSESTEREO     0x40000

#define AOUT_CHAN_PHYSMASK          0xFFFF
#define AOUT_CHAN_MAX               9

/* Values used for the audio-device and audio-channels object variables */
#define AOUT_VAR_MONO               1
#define AOUT_VAR_STEREO             2
#define AOUT_VAR_2F2R               4
#define AOUT_VAR_3F2R               5
#define AOUT_VAR_5_1                6
#define AOUT_VAR_6_1                7
#define AOUT_VAR_7_1                8
#define AOUT_VAR_SPDIF              10

#define AOUT_VAR_CHAN_STEREO        1
#define AOUT_VAR_CHAN_RSTEREO       2
#define AOUT_VAR_CHAN_LEFT          3
#define AOUT_VAR_CHAN_RIGHT         4
#define AOUT_VAR_CHAN_DOLBYS        5

/*****************************************************************************
 * Main audio output structures
 *****************************************************************************/

/** audio output buffer */
struct aout_buffer_t
{
    uint8_t *               p_buffer;
    int                     i_alloc_type;
    /* i_size is the real size of the buffer (used for debug ONLY), i_nb_bytes
     * is the number of significative bytes in it. */
    size_t                  i_size, i_nb_bytes;
    unsigned int            i_nb_samples;
    mtime_t                 start_date, end_date;
    bool                    b_discontinuity; /* Set on discontinuity (for non pcm stream) */

    struct aout_buffer_t *  p_next;

    /** Private data (aout_buffer_t will disappear soon so no need for an
     * aout_buffer_sys_t type) */
    void * p_sys;

    /** This way the release can be overloaded */
    void (*pf_release)( aout_buffer_t * );
};

#define aout_BufferFree( p_buffer ) do {                                    \
    if( p_buffer != NULL && (p_buffer)->i_alloc_type == AOUT_ALLOC_HEAP )   \
    {                                                                       \
        free( p_buffer );                                                   \
    }                                                                       \
    p_buffer = NULL; } while(0)

/* Size of a frame for S/PDIF output. */
#define AOUT_SPDIF_SIZE 6144

/* Number of samples in an A/52 frame. */
#define A52_FRAME_NB 1536

/* Max input rate factor (1/4 -> 4) */
#define AOUT_MAX_INPUT_RATE (4)

/** date incrementation helper structure without long-term
 * rounding errors
 */
struct audio_date_t
{
    mtime_t  date;
    uint32_t i_divider;
    uint32_t i_remainder;
};

/** allocation of memory in the audio output */
typedef struct aout_alloc_t
{
    int                     i_alloc_type;
    int                     i_bytes_per_sec;
} aout_alloc_t;

#define AOUT_ALLOC_NONE     0
#define AOUT_ALLOC_STACK    1
#define AOUT_ALLOC_HEAP     2

/** audio output mixer */
typedef struct aout_mixer_t
{
    audio_sample_format_t   mixer;
    aout_alloc_t            output_alloc;

    module_t *              p_module;
    struct aout_mixer_sys_t * p_sys;
    void                 (* pf_do_work)( struct aout_instance_t *,
                                         struct aout_buffer_t * );

    /** If b_error == 1, there is no mixer. */
    bool              b_error;
    /** Multiplier used to raise or lower the volume of the sound in
     * software. Beware, this creates sound distortion and should be avoided
     * as much as possible. This isn't available for non-float32 mixer. */
    float                   f_multiplier;
} aout_mixer_t;

/** audio output buffer FIFO */
struct aout_fifo_t
{
    aout_buffer_t *         p_first;
    aout_buffer_t **        pp_last;
    audio_date_t            end_date;
};

/* */
typedef struct
{
    vout_thread_t  *(*pf_request_vout)( void *,