float.c

VLC Player Source Code

    return 0;
}

static void Do_FL32ToU8( aout_instance_t * p_aout, aout_filter_t * p_filter,
                         aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
{
    VLC_UNUSED(p_aout);
    int i;
    float * p_in = (float *)p_in_buf->p_buffer;
    uint8_t * p_out = (uint8_t *)p_out_buf->p_buffer;

    for ( i = p_in_buf->i_nb_samples
               * aout_FormatNbChannels( &p_filter->input ); i-- ; )
    {
        if ( *p_in >= 1.0 ) *p_out = 255;
        else if ( *p_in < -1.0 ) *p_out = 0;
        else *p_out = (uint8_t)(128 + *p_in * 128);
        p_in++; p_out++;
    }

    p_out_buf->i_nb_samples = p_in_buf->i_nb_samples;
    p_out_buf->i_nb_bytes = p_in_buf->i_nb_bytes / 4;
}

/*****************************************************************************
 * S16 To Float32
 *****************************************************************************/
static int Create_S16ToFL32( vlc_object_t *p_this )
{
    aout_filter_t * p_filter = (aout_filter_t *)p_this;

    if ( ( p_filter->input.i_format != AOUT_FMT_S16_NE &&
           p_filter->input.i_format != AOUT_FMT_S24_NE &&
           p_filter->input.i_format != AOUT_FMT_S32_NE )
          || p_filter->output.i_format != VLC_FOURCC('f','l','3','2') )
    {
        return -1;
    }

    if ( !AOUT_FMTS_SIMILAR( &p_filter->input, &p_filter->output ) )
    {
        return -1;
    }

    if( p_filter->input.i_format == AOUT_FMT_S32_NE )
        p_filter->pf_do_work = Do_S32ToFL32;
    else if( p_filter->input.i_format == AOUT_FMT_S24_NE )
        p_filter->pf_do_work = Do_S24ToFL32;
    else
        p_filter->pf_do_work = Do_S16ToFL32;

    p_filter->b_in_place = true;

    return 0;
}

static void Do_S16ToFL32( aout_instance_t * p_aout, aout_filter_t * p_filter,
                          aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
{
    VLC_UNUSED(p_aout);
    int i = p_in_buf->i_nb_samples * aout_FormatNbChannels( &p_filter->input );

    /* We start from the end because b_in_place is true */
    int16_t * p_in = (int16_t *)p_in_buf->p_buffer + i - 1;
    float * p_out = (float *)p_out_buf->p_buffer + i - 1;

    while( i-- )
    {
#if 0
        /* Slow version */
        *p_out = (float)*p_in / 32768.0;
#else
        /* This is walken's trick based on IEEE float format. On my PIII
         * this takes 16 seconds to perform one billion conversions, instead
         * of 19 seconds for the above division. */
        union { float f; int32_t i; } u;
        u.i = *p_in + 0x43c00000;
        *p_out = u.f - 384.0;
#endif

        p_in--; p_out--;
    }

    p_out_buf->i_nb_samples = p_in_buf->i_nb_samples;
    p_out_buf->i_nb_bytes = p_in_buf->i_nb_bytes * 4 / 2;
}

static void Do_S24ToFL32( aout_instance_t * p_aout, aout_filter_t * p_filter,
                          aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
{
    VLC_UNUSED(p_aout);
    int i = p_in_buf->i_nb_samples * aout_FormatNbChannels( &p_filter->input );

    /* We start from the end because b_in_place is true */
    uint8_t * p_in = (uint8_t *)p_in_buf->p_buffer + (i - 1) * 3;
    float * p_out = (float *)p_out_buf->p_buffer + i - 1;

    while( i-- )
    {
#ifdef WORDS_BIGENDIAN
        *p_out = ((float)( (((int32_t)*(int16_t *)(p_in)) << 8) + p_in[2]))
#else
        *p_out = ((float)( (((int32_t)*(int16_t *)(p_in+1)) << 8) + p_in[0]))
#endif
            / 8388608.0;

        p_in -= 3; p_out--;
    }

    p_out_buf->i_nb_samples = p_in_buf->i_nb_samples;
    p_out_buf->i_nb_bytes = p_in_buf->i_nb_bytes * 4 / 3;
}

static void Do_S32ToFL32( aout_instance_t * p_aout, aout_filter_t * p_filter,
                          aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
{
    VLC_UNUSED(p_aout);
    int i = p_in_buf->i_nb_samples * aout_FormatNbChannels( &p_filter->input );

    /* We start from the end because b_in_place is true */
    int32_t * p_in = (int32_t *)p_in_buf->p_buffer + i - 1;
    float * p_out = (float *)p_out_buf->p_buffer + i - 1;

    while( i-- )
    {
        *p_out-- = (float)*p_in-- / 2147483648.0;
    }

    p_out_buf->i_nb_samples = p_in_buf->i_nb_samples;
    p_out_buf->i_nb_bytes = p_in_buf->i_nb_bytes * 4 / 4;
}

/*****************************************************************************
 * S16 To Float32 with endianness conversion
 *****************************************************************************/
static int Create_S16ToFL32_SW( vlc_object_t *p_this )
{
    aout_filter_t * p_filter = (aout_filter_t *)p_this;

    if ( !AOUT_FMTS_SIMILAR( &p_filter->input, &p_filter->output ) )
    {
        return -1;
    }

    if ( (p_filter->input.i_format == VLC_FOURCC('s','1','6','l') ||
         p_filter->input.i_format == VLC_FOURCC('s','1','6','b'))
         && p_filter->output.i_format == VLC_FOURCC('f','l','3','2')
         && p_filter->input.i_format != AOUT_FMT_S16_NE )
    {
        p_filter->pf_do_work = Do_S16ToFL32_SW;
        p_filter->b_in_place = true;

        return 0;
    }

    if ( (p_filter->input.i_format == VLC_FOURCC('s','2','4','l') ||
         p_filter->input.i_format == VLC_FOURCC('s','2','4','b'))
         && p_filter->output.i_format == VLC_FOURCC('f','l','3','2')
         && p_filter->input.i_format != AOUT_FMT_S24_NE )
    {
        p_filter->pf_do_work = Do_S24ToFL32_SW;
        p_filter->b_in_place = true;

        return 0;
    }

    if ( (p_filter->input.i_format == VLC_FOURCC('s','3','2','l') ||
         p_filter->input.i_format == VLC_FOURCC('s','3','2','b'))
         && p_filter->output.i_format == VLC_FOURCC('f','l','3','2')
         && p_filter->input.i_format != AOUT_FMT_S32_NE )
    {
        p_filter->pf_do_work = Do_S32ToFL32_SW;
        p_filter->b_in_place = true;

        return 0;
    }

    return -1;
}

static void Do_S16ToFL32_SW( aout_instance_t * p_aout, aout_filter_t * p_filter,
                             aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
{
    VLC_UNUSED(p_aout);
    int i = p_in_buf->i_nb_samples * aout_FormatNbChannels( &p_filter->input );

    /* We start from the end because b_in_place is true */
    int16_t * p_in;
    float * p_out = (float *)p_out_buf->p_buffer + i - 1;

#ifdef HAVE_SWAB
#   ifdef HAVE_ALLOCA
    int16_t * p_swabbed = alloca( i * sizeof(int16_t) );
#   else
    int16_t * p_swabbed = malloc( i * sizeof(int16_t) );
#   endif

    swab( p_in_buf->p_buffer, (void *)p_swabbed, i * sizeof(int16_t) );
    p_in = p_swabbed + i - 1;

#else
    uint8_t p_tmp[2];
    p_in = (int16_t *)p_in_buf->p_buffer + i - 1;
#endif

    while( i-- )
    {
#ifndef HAVE_SWAB
        p_tmp[0] = ((uint8_t *)p_in)[1];
        p_tmp[1] = ((uint8_t *)p_in)[0];
        *p_out = (float)( *(int16_t *)p_tmp ) / 32768.0;
#else
        *p_out = (float)*p_in / 32768.0;
#endif
        p_in--; p_out--;
    }

#ifdef HAVE_SWAB
#   ifndef HAVE_ALLOCA
    free( p_swabbed );
#   endif
#endif

    p_out_buf->i_nb_samples = p_in_buf->i_nb_samples;
    p_out_buf->i_nb_bytes = p_in_buf->i_nb_bytes * 4 / 2;
}

static void Do_S24ToFL32_SW( aout_instance_t * p_aout, aout_filter_t * p_filter,
                             aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
{
    VLC_UNUSED(p_aout);
    int i = p_in_buf->i_nb_samples * aout_FormatNbChannels( &p_filter->input );

    /* We start from the end because b_in_place is true */
    uint8_t * p_in = (uint8_t *)p_in_buf->p_buffer + (i - 1) * 3;
    float * p_out = (float *)p_out_buf->p_buffer + i - 1;

    uint8_t p_tmp[3];

    while( i-- )
    {
        p_tmp[0] = p_in[2];
        p_tmp[1] = p_in[1];
        p_tmp[2] = p_in[0];

#ifdef WORDS_BIGENDIAN
        *p_out = ((float)( (((int32_t)*(int16_t *)(p_tmp)) << 8) + p_tmp[2]))
#else
        *p_out = ((float)( (((int32_t)*(int16_t *)(p_tmp+1)) << 8) + p_tmp[0]))
#endif
            / 8388608.0;

        p_in -= 3; p_out--;
    }

    p_out_buf->i_nb_samples = p_in_buf->i_nb_samples;
    p_out_buf->i_nb_bytes = p_in_buf->i_nb_bytes * 4 / 3;
}

static void Do_S32ToFL32_SW( aout_instance_t * p_aout, aout_filter_t * p_filter,
                             aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
{
    VLC_UNUSED(p_aout);
    int i = p_in_buf->i_nb_samples * aout_FormatNbChannels( &p_filter->input );

    /* We start from the end because b_in_place is true */
    int32_t * p_in = (int32_t *)p_in_buf->p_buffer + i - 1;
    float * p_out = (float *)p_out_buf->p_buffer + i - 1;

    while( i-- )
    {
        *p_out-- = (float)*p_in-- / 2147483648.0;
    }

    p_out_buf->i_nb_samples = p_in_buf->i_nb_samples;
    p_out_buf->i_nb_bytes = p_in_buf->i_nb_bytes * 4 / 4;
}


/*****************************************************************************
 * S8 To FL32
 *****************************************************************************/
static int Create_S8ToFL32( vlc_object_t *p_this )
{
    aout_filter_t * p_filter = (aout_filter_t *)p_this;

    if ( p_filter->input.i_format != VLC_FOURCC('s','8',' ',' ')
          || p_filter->output.i_format != VLC_FOURCC('f','l','3','2') )
    {
        return -1;
    }

    if ( !AOUT_FMTS_SIMILAR( &p_filter->input, &p_filter->output ) )
    {
        return -1;
    }

    p_filter->pf_do_work = Do_S8ToFL32;
    p_filter->b_in_place = true;

    return 0;
}

static void Do_S8ToFL32( aout_instance_t * p_aout, aout_filter_t * p_filter,
                         aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
{
    VLC_UNUSED(p_aout);
    int i = p_in_buf->i_nb_samples * aout_FormatNbChannels( &p_filter->input );

    /* We start from the end because b_in_place is true */
    int8_t * p_in = (int8_t *)p_in_buf->p_buffer + i - 1;
    float * p_out = (float *)p_out_buf->p_buffer + i - 1;

    while( i-- )
    {
        *p_out = (float)(*p_in) / 128.0;
        p_in--; p_out--;
    }

    p_out_buf->i_nb_samples = p_in_buf->i_nb_samples;
    p_out_buf->i_nb_bytes = p_in_buf->i_nb_bytes * sizeof(float);
}

/*****************************************************************************
 * U8 To FL32
 *****************************************************************************/
static int Create_U8ToFL32( vlc_object_t *p_this )
{
    aout_filter_t * p_filter = (aout_filter_t *)p_this;

    if ( p_filter->input.i_format != VLC_FOURCC('u','8',' ',' ')
          || p_filter->output.i_format != VLC_FOURCC('f','l','3','2') )
    {
        return -1;
    }

    if ( !AOUT_FMTS_SIMILAR( &p_filter->input, &p_filter->output ) )
    {
        return -1;
    }

    p_filter->pf_do_work = Do_U8ToFL32;
    p_filter->b_in_place = true;

    return 0;
}

static void Do_U8ToFL32( aout_instance_t * p_aout, aout_filter_t * p_filter,
                         aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
{
    VLC_UNUSED(p_aout);
    int i = p_in_buf->i_nb_samples * aout_FormatNbChannels( &p_filter->input );

    /* We start from the end because b_in_place is true */
    uint8_t * p_in = (uint8_t *)p_in_buf->p_buffer + i - 1;
    float * p_out = (float *)p_out_buf->p_buffer + i - 1;

    while( i-- )
    {
        *p_out = ((float)*p_in -128) / 128.0;
        p_in--; p_out--;
    }

    p_out_buf->i_nb_samples = p_in_buf->i_nb_samples;
    p_out_buf->i_nb_bytes = p_in_buf->i_nb_bytes * sizeof(float);
}