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// HACK: Instead of using the full st_i.h (and then st.h and stconfig.h etc.)
// from SoX, we use this minimal variant which is just sufficient to make
// resample.c and rate.c compile.
#ifndef RATE_H
#define RATE_H
#include <stdio.h>
#include <assert.h>
#include "scummsys.h"
#include "common/engine.h"
#include "common/util.h"
#include "audiostream.h"
typedef int16 st_sample_t;
typedef uint16 st_volume_t;
typedef uint32 st_size_t;
typedef uint32 st_rate_t;
typedef struct {
byte priv[1024];
} eff_struct;
typedef eff_struct *eff_t;
/* Minimum and maximum values a sample can hold. */
#define ST_SAMPLE_MAX 0x7fffL
#define ST_SAMPLE_MIN (-ST_SAMPLE_MAX - 1L)
#define ST_EOF (-1)
#define ST_SUCCESS (0)
static inline void clampedAdd(int16& a, int b) {
int val = a + b;
if (val > ST_SAMPLE_MAX)
a = ST_SAMPLE_MAX;
else if (val < ST_SAMPLE_MIN)
a = ST_SAMPLE_MIN;
else
a = val;
}
// Q&D hack to get this SOX stuff to work
#define st_report warning
#define st_warn warning
#define st_fail error
class RateConverter {
protected:
eff_struct effp;
public:
RateConverter() {}
virtual ~RateConverter() {}
virtual int flow(AudioInputStream &input, st_sample_t *obuf, st_size_t *osamp, st_volume_t vol) = 0;
virtual int drain(st_sample_t *obuf, st_size_t *osamp, st_volume_t vol) = 0;
};
class LinearRateConverter : public RateConverter {
public:
LinearRateConverter(st_rate_t inrate, st_rate_t outrate);
virtual int flow(AudioInputStream &input, st_sample_t *obuf, st_size_t *osamp, st_volume_t vol);
virtual int drain(st_sample_t *obuf, st_size_t *osamp, st_volume_t vol);
};
class ResampleRateConverter : public RateConverter {
public:
ResampleRateConverter(st_rate_t inrate, st_rate_t outrate, int quality);
~ResampleRateConverter();
virtual int flow(AudioInputStream &input, st_sample_t *obuf, st_size_t *osamp, st_volume_t vol);
virtual int drain(st_sample_t *obuf, st_size_t *osamp, st_volume_t vol);
};
template<bool stereo>
class CopyRateConverter : public RateConverter {
public:
virtual int flow(AudioInputStream &input, st_sample_t *obuf, st_size_t *osamp, st_volume_t vol) {
int16 tmp;
st_size_t len = *osamp;
assert(input.isStereo() == stereo);
while (!input.eof() && len--) {
tmp = input.read() * vol / 256;
clampedAdd(*obuf++, tmp);
if (stereo)
tmp = input.read() * vol / 256;
clampedAdd(*obuf++, tmp);
}
return (ST_SUCCESS);
}
virtual int drain(st_sample_t *obuf, st_size_t *osamp, st_volume_t vol) {
return (ST_SUCCESS);
}
};
static inline RateConverter *makeRateConverter(st_rate_t inrate, st_rate_t outrate, bool stereo) {
// printf("makeRateConverter: inrate %d, outrate %d\n", inrate, outrate);
if (inrate != outrate) {
return new LinearRateConverter(inrate, outrate);
//return new ResampleRateConverter(inrate, outrate, 1);
} else {
if (stereo)
return new CopyRateConverter<true>();
else
return new CopyRateConverter<false>();
}
}
#endif
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