audio_math Namespace Reference

Functions
void SHARED_EXPORT	add_offset (audio_sample *p_buffer, audio_sample p_delta, t_size p_count)
audio_sample SHARED_EXPORT	calculate_peak (const audio_sample *p_source, t_size p_count)
void SHARED_EXPORT	convert_from_int16 (const t_int16 *p_source, t_size p_count, audio_sample *p_output, audio_sample p_scale)
void SHARED_EXPORT	convert_from_int32 (const t_int32 *p_source, t_size p_count, audio_sample *p_output, audio_sample p_scale)
void SHARED_EXPORT	convert_to_int16 (const audio_sample *p_source, t_size p_count, t_int16 *p_output, audio_sample p_scale)
audio_sample SHARED_EXPORT	convert_to_int16_calculate_peak (const audio_sample *p_source, t_size p_count, t_int16 *p_output, audio_sample p_scale)
void SHARED_EXPORT	convert_to_int32 (const audio_sample *p_source, t_size p_count, t_int32 *p_output, audio_sample p_scale)
audio_sample SHARED_EXPORT	convert_to_int32_calculate_peak (const audio_sample *p_source, t_size p_count, t_int32 *p_output, audio_sample p_scale)
audio_sample	decodeFloat16 (uint16_t source)
audio_sample	decodeFloat24ptr (const void *sourcePtr)
audio_sample	decodeFloat24ptrbs (const void *sourcePtr)
audio_sample	gain_to_scale (double p_gain)
void	kill_denormal (audio_sample *p_buffer, t_size p_count)
void SHARED_EXPORT	remove_denormals (audio_sample *p_buffer, t_size p_count)
static t_int32	rint32 (audio_sample val)
static t_int64	rint64 (audio_sample val)
double	samples_to_time (t_uint64 p_samples, t_uint32 p_sample_rate)
void SHARED_EXPORT	scale (const audio_sample *p_source, t_size p_count, audio_sample *p_output, audio_sample p_scale)
double	scale_to_gain (double scale)
t_uint64	time_to_samples (double p_time, t_uint32 p_sample_rate)

Variables
static const audio_sample	float16scale = 65536.f

Function Documentation

void audio_math::add_offset	(	audio_sample *	p_buffer,
		audio_sample	p_delta,
		t_size	p_count
	)

Definition at line 135 of file audio_math.cpp.

                                                                                 {
        for(t_size n=0;n<p_count;n++) {
            p_buffer[n] += p_delta;
        }
    }

audio_sample audio_math::calculate_peak	(	const audio_sample *	p_source,
		t_size	p_count
	)

Definition at line 108 of file audio_math.cpp.

    {
        return noopt_calculate_peak(p_source,p_count);
    }

void audio_math::convert_from_int16	(	const t_int16 *	p_source,
		t_size	p_count,
		audio_sample *	p_output,
		audio_sample	p_scale
	)

Definition at line 81 of file audio_math.cpp.

    {
        audio_sample scale = (audio_sample) ( p_scale / (double) 0x8000 );
        noopt_convert_from_int16(p_source,p_count,p_output,scale);
    }

void audio_math::convert_from_int32	(	const t_int32 *	p_source,
		t_size	p_count,
		audio_sample *	p_output,
		audio_sample	p_scale
	)

Definition at line 101 of file audio_math.cpp.

    {
        audio_sample scale = (audio_sample) ( p_scale / (double) 0x80000000 );
        noopt_convert_from_int32(p_source,p_count,p_output,scale);
    }

void audio_math::convert_to_int16	(	const audio_sample *	p_source,
		t_size	p_count,
		t_int16 *	p_output,
		audio_sample	p_scale
	)

Definition at line 68 of file audio_math.cpp.

    {
        audio_sample scale = (audio_sample)(p_scale * 0x8000);
        noopt_convert_to_16bit(p_source,p_count,p_output,scale);
    }

audio_sample audio_math::convert_to_int16_calculate_peak	(	const audio_sample *	p_source,
		t_size	p_count,
		t_int16 *	p_output,
		audio_sample	p_scale
	)

Definition at line 74 of file audio_math.cpp.

    {
        //todo?
        convert_to_int16(p_source,p_count,p_output,p_scale);
        return p_scale * calculate_peak(p_source,p_count);
    }

void audio_math::convert_to_int32	(	const audio_sample *	p_source,
		t_size	p_count,
		t_int32 *	p_output,
		audio_sample	p_scale
	)

Definition at line 87 of file audio_math.cpp.

    {
        audio_sample scale = (audio_sample)(p_scale * 0x80000000);
        {
            noopt_convert_to_32bit(p_source,p_count,p_output,scale);
        }
    }

audio_sample audio_math::convert_to_int32_calculate_peak	(	const audio_sample *	p_source,
		t_size	p_count,
		t_int32 *	p_output,
		audio_sample	p_scale
	)

Definition at line 95 of file audio_math.cpp.

    {
        convert_to_int32(p_source,p_count,p_output,p_scale);
        return p_scale * calculate_peak(p_source,p_count);
    }

audio_sample audio_math::decodeFloat16

(

uint16_t

source

)

Definition at line 31 of file audio_sample.cpp.

                                                {
        const unsigned fractionBits = 10;
        const unsigned widthBits = 16;
        typedef uint16_t source_t;

    /*  typedef uint64_t out_t; typedef double retval_t;
        enum { 
            outExponent = 11, 
            outFraction = 52, 
            outExponentShift = (1 << (outExponent-1))-1 
        };*/

        typedef uint32_t out_t; typedef float retval_t;
        enum { 
            outExponent = 8, 
            outFraction = 23, 
            outExponentShift = (1 << (outExponent-1))-1 
        };

        const unsigned exponentBits = widthBits - fractionBits - 1;
        // 1 bit sign | exponent | fraction
        source_t fraction = source & (((source_t)1 << fractionBits)-1);
        source >>= fractionBits;
        int exponent = (int)( source & (((source_t)1 << exponentBits)-1) ) - (int)((1 << (exponentBits-1))-1);
        source >>= exponentBits;

        if (outExponent + outExponentShift <= 0) return 0;

        out_t output = (out_t)( source&1 );
        output <<= outExponent;
        output |= (unsigned) (exponent + outExponentShift) & ( (1<<outExponent) - 1 );
        output <<= outFraction;
        int shift = (int) outFraction - (int) fractionBits;
        if (shift < 0) output |= (out_t) (fraction >> -shift);
        else output |= (out_t) (fraction << shift);
        return *(retval_t*)&output / float16scale;
    }

audio_sample audio_math::decodeFloat24ptr

(

const void *

sourcePtr

)

Definition at line 4 of file audio_sample.cpp.

                                                          {
        PFC_STATIC_ASSERT(pfc::byte_order_is_little_endian);
        union {
            uint8_t bytes[4];
            float v;
        } u;
        const uint8_t * s = reinterpret_cast<const uint8_t*>(sourcePtr);
        u.bytes[0] = 0;
        u.bytes[1] = s[0];
        u.bytes[2] = s[1];
        u.bytes[3] = s[2];
        return u.v;
    }

audio_sample audio_math::decodeFloat24ptrbs

(

const void *

sourcePtr

)

Definition at line 17 of file audio_sample.cpp.

                                                            {
        PFC_STATIC_ASSERT(pfc::byte_order_is_little_endian);
        union {
            uint8_t bytes[4];
            float v;
        } u;
        const uint8_t * s = reinterpret_cast<const uint8_t*>(sourcePtr);
        u.bytes[0] = 0;
        u.bytes[1] = s[2];
        u.bytes[2] = s[1];
        u.bytes[3] = s[0];
        return u.v;
    }

audio_sample audio_math::gain_to_scale ( double  p_gain )

inline

Definition at line 71 of file audio_sample.h.

{return (audio_sample) pow(10.0,p_gain / 20.0);}

void audio_math::kill_denormal	(	audio_sample *	p_buffer,
		t_size	p_count
	)

Definition at line 113 of file audio_math.cpp.

                                                               {
#if audio_sample_size == 32
        t_uint32 * ptr = reinterpret_cast<t_uint32*>(p_buffer);
        for(;p_count;p_count--)
        {
            t_uint32 t = *ptr;
            if ((t & 0x007FFFFF) && !(t & 0x7F800000)) *ptr=0;
            ptr++;
        }
#elif audio_sample_size == 64
        t_uint64 * ptr = reinterpret_cast<t_uint64*>(p_buffer);
        for(;p_count;p_count--)
        {
            t_uint64 t = *ptr;
            if ((t & 0x000FFFFFFFFFFFFF) && !(t & 0x7FF0000000000000)) *ptr=0;
            ptr++;
        }
#else
#error unsupported
#endif
    }

void audio_math::remove_denormals	(	audio_sample *	p_buffer,
		t_size	p_count
	)

static t_int32 audio_math::rint32 ( audio_sample  val )

inlinestatic

Definition at line 52 of file audio_sample.h.

                                                   {
        t_int32 rv; 
        _asm {
            fld val;
            fistp rv;
        }
        return rv;
    }

static t_int64 audio_math::rint64 ( audio_sample  val )

inlinestatic

Definition at line 44 of file audio_sample.h.

                                                   {
        t_int64 rv;
        _asm {
            fld val;
            fistp rv;
        }
        return rv;
    }

double audio_math::samples_to_time ( t_uint64  p_samples, t_uint32  p_sample_rate  )

inline

Definition at line 37 of file audio_sample.h.

                                                                             {
        PFC_ASSERT(p_sample_rate > 0);
        return (double) p_samples / (double) p_sample_rate;
    }

void audio_math::scale	(	const audio_sample *	p_source,
		t_size	p_count,
		audio_sample *	p_output,
		audio_sample	p_scale
	)

p_source/p_output can point to same buffer

Definition at line 63 of file audio_math.cpp.

    {
        noopt_scale(p_source,p_count,p_output,p_scale);
    }

double audio_math::scale_to_gain ( double  scale )

inline

Definition at line 72 of file audio_sample.h.

{return 20.0*log10(scale);}

t_uint64 audio_math::time_to_samples ( double  p_time, t_uint32  p_sample_rate  )

inline

Definition at line 33 of file audio_sample.h.

                                                                          {
        return (t_uint64)floor((double)p_sample_rate * p_time + 0.5);
    }

Variable Documentation

const audio_sample audio_math::float16scale = 65536.f

static

Definition at line 75 of file audio_sample.h.