Archipelago » qemu

/*

 * QEMU Mixing engine

 *

 * Copyright (c) 2004-2005 Vassili Karpov (malc)

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 */

/*

 * Tusen tack till Mike Nordell

 * dec++'ified by Dscho

 */

#ifndef SIGNED

#define HALF (IN_MAX >> 1)

#endif

#define ET glue (ENDIAN_CONVERSION, glue (_, IN_T))

#ifdef FLOAT_MIXENG

static mixeng_real inline glue (conv_, ET) (IN_T v)

{

    IN_T nv = ENDIAN_CONVERT (v);

#ifdef RECIPROCAL

#ifdef SIGNED

    return nv * (1.f / (mixeng_real) (IN_MAX - IN_MIN));

#else

    return (nv - HALF) * (1.f / (mixeng_real) IN_MAX);

#endif

#else  /* !RECIPROCAL */

#ifdef SIGNED

    return nv / (mixeng_real) ((mixeng_real) IN_MAX - IN_MIN);

#else

    return (nv - HALF) / (mixeng_real) IN_MAX;

#endif

#endif

}

static IN_T inline glue (clip_, ET) (mixeng_real v)

{

    if (v >= 0.5) {

        return IN_MAX;

    }

    else if (v < -0.5) {

        return IN_MIN;

    }

#ifdef SIGNED

    return ENDIAN_CONVERT ((IN_T) (v * ((mixeng_real) IN_MAX - IN_MIN)));

#else

    return ENDIAN_CONVERT ((IN_T) ((v * IN_MAX) + HALF));

#endif

}

#else  /* !FLOAT_MIXENG */

static inline int64_t glue (conv_, ET) (IN_T v)

{

    IN_T nv = ENDIAN_CONVERT (v);

#ifdef SIGNED

    return ((int64_t) nv) << (32 - SHIFT);

#else

    return ((int64_t) nv - HALF) << (32 - SHIFT);

#endif

}

static inline IN_T glue (clip_, ET) (int64_t v)

{

    if (v >= 0x7f000000) {

        return IN_MAX;

    }

    else if (v < -2147483648LL) {

        return IN_MIN;

    }

#ifdef SIGNED

    return ENDIAN_CONVERT ((IN_T) (v >> (32 - SHIFT)));

#else

    return ENDIAN_CONVERT ((IN_T) ((v >> (32 - SHIFT)) + HALF));

#endif

}

#endif

static void glue (glue (conv_, ET), _to_stereo)

    (struct st_sample *dst, const void *src, int samples)

{

    struct st_sample *out = dst;

    IN_T *in = (IN_T *) src;

    while (samples--) {

        out->l = glue (conv_, ET) (*in++);

        out->r = glue (conv_, ET) (*in++);

        out += 1;

    }

}

static void glue (glue (conv_, ET), _to_mono)

    (struct st_sample *dst, const void *src, int samples)

{

    struct st_sample *out = dst;

    IN_T *in = (IN_T *) src;

    while (samples--) {

        out->l = glue (conv_, ET) (in[0]);

        out->r = out->l;

        out += 1;

        in += 1;

    }

}

static void glue (glue (clip_, ET), _from_stereo)

    (void *dst, const struct st_sample *src, int samples)

{

    const struct st_sample *in = src;

    IN_T *out = (IN_T *) dst;

    while (samples--) {

        *out++ = glue (clip_, ET) (in->l);

        *out++ = glue (clip_, ET) (in->r);

        in += 1;

    }

}

static void glue (glue (clip_, ET), _from_mono)

    (void *dst, const struct st_sample *src, int samples)

{

    const struct st_sample *in = src;

    IN_T *out = (IN_T *) dst;

    while (samples--) {

        *out++ = glue (clip_, ET) (in->l + in->r);

        in += 1;

    }

}

#undef ET

#undef HALF