/* MPGLIB replacement using mpega.library (AmigaOS)

 * Written by Thomas Wenzel and Sigbjrn (CISC) Skj�et.

 *

 * Big thanks to St�hane Tavernard for mpega.library.

 *

 */

/* $Id: amiga_mpega.c,v 1.3 2005/11/01 13:01:56 robert Exp $ */

#ifdef HAVE_CONFIG_H

#include <config.h>

#endif

#ifdef AMIGA_MPEGA

#define __USE_SYSBASE

#include "lame.h"

#include <stdio.h>

#include <stdlib.h>

/* We need a small workaround here so GCC doesn't fail upon redefinition. :P */

#define FLOAT _FLOAT

#include <proto/exec.h>

#include <proto/mpega.h>

#undef _FLOAT

#ifndef __GNUC__

#include <dos.h>

#endif

struct Library *MPEGABase = NULL;

MPEGA_STREAM *mstream = NULL;

MPEGA_CTRL mctrl;

static const int smpls[2][4] = {

/* Layer x  I   II   III */

    {0, 384, 1152, 1152}, /* MPEG-1     */

    {0, 384, 1152, 576} /* MPEG-2(.5) */

};

#ifndef __GNUC__

static int

break_cleanup(void)

{

    /* Dummy break function to make atexit() work. :P */

    return 1;

}

#endif

static void

exit_cleanup(void)

{

    if (mstream) {

        MPEGA_close(mstream);

        mstream = NULL;

    }

    if (MPEGABase) {

        CloseLibrary(MPEGABase);

        MPEGABase = NULL;

    }

}

int

lame_decode_initfile(const char *fullname, mp3data_struct * mp3data)

{

    mctrl.bs_access = NULL;

    mctrl.layer_1_2.mono.quality = 2;

    mctrl.layer_1_2.stereo.quality = 2;

    mctrl.layer_1_2.mono.freq_div = 1;

    mctrl.layer_1_2.stereo.freq_div = 1;

    mctrl.layer_1_2.mono.freq_max = 48000;

    mctrl.layer_1_2.stereo.freq_max = 48000;

    mctrl.layer_3.mono.quality = 2;

    mctrl.layer_3.stereo.quality = 2;

    mctrl.layer_3.mono.freq_div = 1;

    mctrl.layer_3.stereo.freq_div = 1;

    mctrl.layer_3.mono.freq_max = 48000;

    mctrl.layer_3.stereo.freq_max = 48000;

    mctrl.layer_1_2.force_mono = 0;

    mctrl.layer_3.force_mono = 0;

    MPEGABase = OpenLibrary("mpega.library", 2);

    if (!MPEGABase) {

        error_printf("Unable to open mpega.library v2\n");

        exit(1);

    }

#ifndef __GNUC__

    onbreak(break_cleanup);

#endif

    atexit(exit_cleanup);

    mp3data->header_parsed = 0;

    mstream = MPEGA_open((char *) fullname, &mctrl);

    if (!mstream)

        return (-1);

    mp3data->header_parsed = 1;

    mp3data->stereo = mstream->dec_channels;

    mp3data->samplerate = mstream->dec_frequency;

    mp3data->bitrate = mstream->bitrate;

    mp3data->nsamp = (float) mstream->ms_duration / 1000 * mstream->dec_frequency;

    mp3data->mode = mstream->mode;

    mp3data->mode_ext = 0; /* mpega.library doesn't supply this info! :( */

    mp3data->framesize = smpls[mstream->norm - 1][mstream->layer];

    return 0;

}

int

lame_decode_fromfile(FILE * fd, short pcm_l[], short pcm_r[], mp3data_struct * mp3data)

{

    int     outsize = 0;

    WORD   *b[MPEGA_MAX_CHANNELS];

    b[0] = pcm_l;

    b[1] = pcm_r;

    mp3data->header_parsed = 0;

    while ((outsize == 0) || (outsize == MPEGA_ERR_BADFRAME)) /* Skip bad frames */

        outsize = MPEGA_decode_frame(mstream, b);

    if (outsize < 0)

        return (-1);

    mp3data->header_parsed = 1;

    mp3data->stereo = mstream->dec_channels;

    mp3data->samplerate = mstream->dec_frequency;

    mp3data->bitrate = mstream->bitrate;

    mp3data->mode = mstream->mode;

    mp3data->mode_ext = 0; /* mpega.library doesn't supply this info! :( */

    mp3data->framesize = smpls[mstream->norm - 1][mstream->layer];

    return outsize;

}

#endif /* AMIGA_MPEGA */