Korbs/poke
Korbs/poke
1
Fork 0
Code Activity

add alac source code - part one

Browse source
This commit is contained in:
Ashley 2023-02-12 09:12:54 +00:00
parent beeb2c2af0
commit 3ae7f9c5aa
4 changed files with 892 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

80
alac/codec/makefile Normal file
View file

@ -0,0 +1,80 @@
# libalac make
CFLAGS = -g -O3 -c
LFLAGS = -Wall
CC = g++
SRCDIR = .
OBJDIR = ./obj
INCLUDES = .
HEADERS = \
$(SRCDIR)/EndianPortable.h \
$(SRCDIR)/aglib.h \
$(SRCDIR)/ALACAudioTypes.h \
$(SRCDIR)/ALACBitUtilities.h\
$(SRCDIR)/ALACDecoder.h \
$(SRCDIR)/ALACEncoder.h \
$(SRCDIR)/dplib.h \
$(SRCDIR)/matrixlib.h
SOURCES = \
$(SRCDIR)/EndianPortable.c \
$(SRCDIR)/ALACBitUtilities.c \
$(SRCDIR)/ALACDecoder.cpp \
$(SRCDIR)/ALACEncoder.cpp \
$(SRCDIR)/ag_dec.c \
$(SRCDIR)/ag_enc.c \
$(SRCDIR)/dp_dec.c \
$(SRCDIR)/dp_enc.c \
$(SRCDIR)/matrix_dec.c \
$(SRCDIR)/matrix_enc.c
OBJS = \
EndianPortable.o \
ALACBitUtilities.o \
ALACDecoder.o \
ALACEncoder.o \
ag_dec.o \
ag_enc.o \
dp_dec.o \
dp_enc.o \
matrix_dec.o \
matrix_enc.o
libalac.a: $(OBJS)
ar rcs libalac.a $(OBJS)
EndianPortable.o : EndianPortable.c
$(CC) -I $(INCLUDES) $(CFLAGS) EndianPortable.c
ALACBitUtilities.o : ALACBitUtilities.c
$(CC) -I $(INCLUDES) $(CFLAGS) ALACBitUtilities.c
ALACDecoder.o : ALACDecoder.cpp
$(CC) -I $(INCLUDES) $(CFLAGS) ALACDecoder.cpp
ALACEncoder.o : ALACEncoder.cpp
$(CC) -I $(INCLUDES) $(CFLAGS) ALACEncoder.cpp
ag_dec.o : ag_dec.c
$(CC) -I $(INCLUDES) $(CFLAGS) ag_dec.c
ag_enc.o : ag_enc.c
$(CC) -I $(INCLUDES) $(CFLAGS) ag_enc.c
dp_dec.o : dp_dec.c
$(CC) -I $(INCLUDES) $(CFLAGS) dp_dec.c
dp_enc.o : dp_enc.c
$(CC) -I $(INCLUDES) $(CFLAGS) dp_enc.c
matrix_dec.o : matrix_dec.c
$(CC) -I $(INCLUDES) $(CFLAGS) matrix_dec.c
matrix_enc.o : matrix_enc.c
$(CC) -I $(INCLUDES) $(CFLAGS) matrix_enc.c
clean:
-rm $(OBJS) libalac.a

390
alac/codec/matrix_dec.c Normal file
View file

@ -0,0 +1,390 @@
/*
* Copyright (c) 2011 Apple Inc. All rights reserved.
*
* @APPLE_APACHE_LICENSE_HEADER_START@
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* @APPLE_APACHE_LICENSE_HEADER_END@
*/
/*
File: matrix_dec.c
Contains: ALAC mixing/matrixing decode routines.
Copyright: (c) 2004-2011 Apple, Inc.
*/
#include "matrixlib.h"
#include "ALACAudioTypes.h"
// up to 24-bit "offset" macros for the individual bytes of a 20/24-bit word
#if TARGET_RT_BIG_ENDIAN
#define LBYTE 2
#define MBYTE 1
#define HBYTE 0
#else
#define LBYTE 0
#define MBYTE 1
#define HBYTE 2
#endif
/*
There is no plain middle-side option; instead there are various mixing
modes including middle-side, each lossless, as embodied in the mix()
and unmix() functions. These functions exploit a generalized middle-side
transformation:
u := [(rL + (m-r)R)/m];
v := L - R;
where [ ] denotes integer floor. The (lossless) inverse is
L = u + v - [rV/m];
R = L - v;
*/
// 16-bit routines
void unmix16( int32_t * u, int32_t * v, int16_t * out, uint32_t stride, int32_t numSamples, int32_t mixbits, int32_t mixres )
{
int16_t * op = out;
int32_t j;
if ( mixres != 0 )
{
/* matrixed stereo */
for ( j = 0; j < numSamples; j++ )
{
int32_t l, r;
l = u[j] + v[j] - ((mixres * v[j]) >> mixbits);
r = l - v[j];
op[0] = (int16_t) l;
op[1] = (int16_t) r;
op += stride;
}
}
else
{
/* Conventional separated stereo. */
for ( j = 0; j < numSamples; j++ )
{
op[0] = (int16_t) u[j];
op[1] = (int16_t) v[j];
op += stride;
}
}
}
// 20-bit routines
// - the 20 bits of data are left-justified in 3 bytes of storage but right-aligned for input/output predictor buffers
void unmix20( int32_t * u, int32_t * v, uint8_t * out, uint32_t stride, int32_t numSamples, int32_t mixbits, int32_t mixres )
{
uint8_t * op = out;
int32_t j;
if ( mixres != 0 )
{
/* matrixed stereo */
for ( j = 0; j < numSamples; j++ )
{
int32_t l, r;
l = u[j] + v[j] - ((mixres * v[j]) >> mixbits);
r = l - v[j];
l <<= 4;
r <<= 4;
op[HBYTE] = (uint8_t)((l >> 16) & 0xffu);
op[MBYTE] = (uint8_t)((l >> 8) & 0xffu);
op[LBYTE] = (uint8_t)((l >> 0) & 0xffu);
op += 3;
op[HBYTE] = (uint8_t)((r >> 16) & 0xffu);
op[MBYTE] = (uint8_t)((r >> 8) & 0xffu);
op[LBYTE] = (uint8_t)((r >> 0) & 0xffu);
op += (stride - 1) * 3;
}
}
else
{
/* Conventional separated stereo. */
for ( j = 0; j < numSamples; j++ )
{
int32_t val;
val = u[j] << 4;
op[HBYTE] = (uint8_t)((val >> 16) & 0xffu);
op[MBYTE] = (uint8_t)((val >> 8) & 0xffu);
op[LBYTE] = (uint8_t)((val >> 0) & 0xffu);
op += 3;
val = v[j] << 4;
op[HBYTE] = (uint8_t)((val >> 16) & 0xffu);
op[MBYTE] = (uint8_t)((val >> 8) & 0xffu);
op[LBYTE] = (uint8_t)((val >> 0) & 0xffu);
op += (stride - 1) * 3;
}
}
}
// 24-bit routines
// - the 24 bits of data are right-justified in the input/output predictor buffers
void unmix24( int32_t * u, int32_t * v, uint8_t * out, uint32_t stride, int32_t numSamples,
int32_t mixbits, int32_t mixres, uint16_t * shiftUV, int32_t bytesShifted )
{
uint8_t * op = out;
int32_t shift = bytesShifted * 8;
int32_t l, r;
int32_t j, k;
if ( mixres != 0 )
{
/* matrixed stereo */
if ( bytesShifted != 0 )
{
for ( j = 0, k = 0; j < numSamples; j++, k += 2 )
{
l = u[j] + v[j] - ((mixres * v[j]) >> mixbits);
r = l - v[j];
l = (l << shift) | (uint32_t) shiftUV[k + 0];
r = (r << shift) | (uint32_t) shiftUV[k + 1];
op[HBYTE] = (uint8_t)((l >> 16) & 0xffu);
op[MBYTE] = (uint8_t)((l >> 8) & 0xffu);
op[LBYTE] = (uint8_t)((l >> 0) & 0xffu);
op += 3;
op[HBYTE] = (uint8_t)((r >> 16) & 0xffu);
op[MBYTE] = (uint8_t)((r >> 8) & 0xffu);
op[LBYTE] = (uint8_t)((r >> 0) & 0xffu);
op += (stride - 1) * 3;
}
}
else
{
for ( j = 0; j < numSamples; j++ )
{
l = u[j] + v[j] - ((mixres * v[j]) >> mixbits);
r = l - v[j];
op[HBYTE] = (uint8_t)((l >> 16) & 0xffu);
op[MBYTE] = (uint8_t)((l >> 8) & 0xffu);
op[LBYTE] = (uint8_t)((l >> 0) & 0xffu);
op += 3;
op[HBYTE] = (uint8_t)((r >> 16) & 0xffu);
op[MBYTE] = (uint8_t)((r >> 8) & 0xffu);
op[LBYTE] = (uint8_t)((r >> 0) & 0xffu);
op += (stride - 1) * 3;
}
}
}
else
{
/* Conventional separated stereo. */
if ( bytesShifted != 0 )
{
for ( j = 0, k = 0; j < numSamples; j++, k += 2 )
{
l = u[j];
r = v[j];
l = (l << shift) | (uint32_t) shiftUV[k + 0];
r = (r << shift) | (uint32_t) shiftUV[k + 1];
op[HBYTE] = (uint8_t)((l >> 16) & 0xffu);
op[MBYTE] = (uint8_t)((l >> 8) & 0xffu);
op[LBYTE] = (uint8_t)((l >> 0) & 0xffu);
op += 3;
op[HBYTE] = (uint8_t)((r >> 16) & 0xffu);
op[MBYTE] = (uint8_t)((r >> 8) & 0xffu);
op[LBYTE] = (uint8_t)((r >> 0) & 0xffu);
op += (stride - 1) * 3;
}
}
else
{
for ( j = 0; j < numSamples; j++ )
{
int32_t val;
val = u[j];
op[HBYTE] = (uint8_t)((val >> 16) & 0xffu);
op[MBYTE] = (uint8_t)((val >> 8) & 0xffu);
op[LBYTE] = (uint8_t)((val >> 0) & 0xffu);
op += 3;
val = v[j];
op[HBYTE] = (uint8_t)((val >> 16) & 0xffu);
op[MBYTE] = (uint8_t)((val >> 8) & 0xffu);
op[LBYTE] = (uint8_t)((val >> 0) & 0xffu);
op += (stride - 1) * 3;
}
}
}
}
// 32-bit routines
// - note that these really expect the internal data width to be < 32 but the arrays are 32-bit
// - otherwise, the calculations might overflow into the 33rd bit and be lost
// - therefore, these routines deal with the specified "unused lower" bytes in the "shift" buffers
void unmix32( int32_t * u, int32_t * v, int32_t * out, uint32_t stride, int32_t numSamples,
int32_t mixbits, int32_t mixres, uint16_t * shiftUV, int32_t bytesShifted )
{
int32_t * op = out;
int32_t shift = bytesShifted * 8;
int32_t l, r;
int32_t j, k;
if ( mixres != 0 )
{
//Assert( bytesShifted != 0 );
/* matrixed stereo with shift */
for ( j = 0, k = 0; j < numSamples; j++, k += 2 )
{
int32_t lt, rt;
lt = u[j];
rt = v[j];
l = lt + rt - ((mixres * rt) >> mixbits);
r = l - rt;
op[0] = (l << shift) | (uint32_t) shiftUV[k + 0];
op[1] = (r << shift) | (uint32_t) shiftUV[k + 1];
op += stride;
}
}
else
{
if ( bytesShifted == 0 )
{
/* interleaving w/o shift */
for ( j = 0; j < numSamples; j++ )
{
op[0] = u[j];
op[1] = v[j];
op += stride;
}
}
else
{
/* interleaving with shift */
for ( j = 0, k = 0; j < numSamples; j++, k += 2 )
{
op[0] = (u[j] << shift) | (uint32_t) shiftUV[k + 0];
op[1] = (v[j] << shift) | (uint32_t) shiftUV[k + 1];
op += stride;
}
}
}
}
// 20/24-bit <-> 32-bit helper routines (not really matrixing but convenient to put here)
void copyPredictorTo24( int32_t * in, uint8_t * out, uint32_t stride, int32_t numSamples )
{
uint8_t * op = out;
int32_t j;
for ( j = 0; j < numSamples; j++ )
{
int32_t val = in[j];
op[HBYTE] = (uint8_t)((val >> 16) & 0xffu);
op[MBYTE] = (uint8_t)((val >> 8) & 0xffu);
op[LBYTE] = (uint8_t)((val >> 0) & 0xffu);
op += (stride * 3);
}
}
void copyPredictorTo24Shift( int32_t * in, uint16_t * shift, uint8_t * out, uint32_t stride, int32_t numSamples, int32_t bytesShifted )
{
uint8_t * op = out;
int32_t shiftVal = bytesShifted * 8;
int32_t j;
//Assert( bytesShifted != 0 );
for ( j = 0; j < numSamples; j++ )
{
int32_t val = in[j];
val = (val << shiftVal) | (uint32_t) shift[j];
op[HBYTE] = (uint8_t)((val >> 16) & 0xffu);
op[MBYTE] = (uint8_t)((val >> 8) & 0xffu);
op[LBYTE] = (uint8_t)((val >> 0) & 0xffu);
op += (stride * 3);
}
}
void copyPredictorTo20( int32_t * in, uint8_t * out, uint32_t stride, int32_t numSamples )
{
uint8_t * op = out;
int32_t j;
// 32-bit predictor values are right-aligned but 20-bit output values should be left-aligned
// in the 24-bit output buffer
for ( j = 0; j < numSamples; j++ )
{
int32_t val = in[j];
op[HBYTE] = (uint8_t)((val >> 12) & 0xffu);
op[MBYTE] = (uint8_t)((val >> 4) & 0xffu);
op[LBYTE] = (uint8_t)((val << 4) & 0xffu);
op += (stride * 3);
}
}
void copyPredictorTo32( int32_t * in, int32_t * out, uint32_t stride, int32_t numSamples )
{
int32_t i, j;
// this is only a subroutine to abstract the "iPod can only output 16-bit data" problem
for ( i = 0, j = 0; i < numSamples; i++, j += stride )
out[j] = in[i];
}
void copyPredictorTo32Shift( int32_t * in, uint16_t * shift, int32_t * out, uint32_t stride, int32_t numSamples, int32_t bytesShifted )
{
int32_t * op = out;
uint32_t shiftVal = bytesShifted * 8;
int32_t j;
//Assert( bytesShifted != 0 );
// this is only a subroutine to abstract the "iPod can only output 16-bit data" problem
for ( j = 0; j < numSamples; j++ )
{
op[0] = (in[j] << shiftVal) | (uint32_t) shift[j];
op += stride;
}
}

342
alac/codec/matrix_enc.c Normal file
View file

@ -0,0 +1,342 @@
/*
* Copyright (c) 2011 Apple Inc. All rights reserved.
*
* @APPLE_APACHE_LICENSE_HEADER_START@
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* @APPLE_APACHE_LICENSE_HEADER_END@
*/
/*
File: matrix_enc.c
Contains: ALAC mixing/matrixing encode routines.
Copyright: (c) 2004-2011 Apple, Inc.
*/
#include "matrixlib.h"
#include "ALACAudioTypes.h"
// up to 24-bit "offset" macros for the individual bytes of a 20/24-bit word
#if TARGET_RT_BIG_ENDIAN
#define LBYTE 2
#define MBYTE 1
#define HBYTE 0
#else
#define LBYTE 0
#define MBYTE 1
#define HBYTE 2
#endif
/*
There is no plain middle-side option; instead there are various mixing
modes including middle-side, each lossless, as embodied in the mix()
and unmix() functions. These functions exploit a generalized middle-side
transformation:
u := [(rL + (m-r)R)/m];
v := L - R;
where [ ] denotes integer floor. The (lossless) inverse is
L = u + v - [rV/m];
R = L - v;
*/
// 16-bit routines
void mix16( int16_t * in, uint32_t stride, int32_t * u, int32_t * v, int32_t numSamples, int32_t mixbits, int32_t mixres )
{
int16_t * ip = in;
int32_t j;
if ( mixres != 0 )
{
int32_t mod = 1 << mixbits;
int32_t m2;
/* matrixed stereo */
m2 = mod - mixres;
for ( j = 0; j < numSamples; j++ )
{
int32_t l, r;
l = (int32_t) ip[0];
r = (int32_t) ip[1];
ip += stride;
u[j] = (mixres * l + m2 * r) >> mixbits;
v[j] = l - r;
}
}
else
{
/* Conventional separated stereo. */
for ( j = 0; j < numSamples; j++ )
{
u[j] = (int32_t) ip[0];
v[j] = (int32_t) ip[1];
ip += stride;
}
}
}
// 20-bit routines
// - the 20 bits of data are left-justified in 3 bytes of storage but right-aligned for input/output predictor buffers
void mix20( uint8_t * in, uint32_t stride, int32_t * u, int32_t * v, int32_t numSamples, int32_t mixbits, int32_t mixres )
{
int32_t l, r;
uint8_t * ip = in;
int32_t j;
if ( mixres != 0 )
{
/* matrixed stereo */
int32_t mod = 1 << mixbits;
int32_t m2 = mod - mixres;
for ( j = 0; j < numSamples; j++ )
{
l = (int32_t)( ((uint32_t)ip[HBYTE] << 16) | ((uint32_t)ip[MBYTE] << 8) | (uint32_t)ip[LBYTE] );
l = (l << 8) >> 12;
ip += 3;
r = (int32_t)( ((uint32_t)ip[HBYTE] << 16) | ((uint32_t)ip[MBYTE] << 8) | (uint32_t)ip[LBYTE] );
r = (r << 8) >> 12;
ip += (stride - 1) * 3;
u[j] = (mixres * l + m2 * r) >> mixbits;
v[j] = l - r;
}
}
else
{
/* Conventional separated stereo. */
for ( j = 0; j < numSamples; j++ )
{
l = (int32_t)( ((uint32_t)ip[HBYTE] << 16) | ((uint32_t)ip[MBYTE] << 8) | (uint32_t)ip[LBYTE] );
u[j] = (l << 8) >> 12;
ip += 3;
r = (int32_t)( ((uint32_t)ip[HBYTE] << 16) | ((uint32_t)ip[MBYTE] << 8) | (uint32_t)ip[LBYTE] );
v[j] = (r << 8) >> 12;
ip += (stride - 1) * 3;
}
}
}
// 24-bit routines
// - the 24 bits of data are right-justified in the input/output predictor buffers
void mix24( uint8_t * in, uint32_t stride, int32_t * u, int32_t * v, int32_t numSamples,
int32_t mixbits, int32_t mixres, uint16_t * shiftUV, int32_t bytesShifted )
{
int32_t l, r;
uint8_t * ip = in;
int32_t shift = bytesShifted * 8;
uint32_t mask = (1ul << shift) - 1;
int32_t j, k;
if ( mixres != 0 )
{
/* matrixed stereo */
int32_t mod = 1 << mixbits;
int32_t m2 = mod - mixres;
if ( bytesShifted != 0 )
{
for ( j = 0, k = 0; j < numSamples; j++, k += 2 )
{
l = (int32_t)( ((uint32_t)ip[HBYTE] << 16) | ((uint32_t)ip[MBYTE] << 8) | (uint32_t)ip[LBYTE] );
l = (l << 8) >> 8;
ip += 3;
r = (int32_t)( ((uint32_t)ip[HBYTE] << 16) | ((uint32_t)ip[MBYTE] << 8) | (uint32_t)ip[LBYTE] );
r = (r << 8) >> 8;
ip += (stride - 1) * 3;
shiftUV[k + 0] = (uint16_t)(l & mask);
shiftUV[k + 1] = (uint16_t)(r & mask);
l >>= shift;
r >>= shift;
u[j] = (mixres * l + m2 * r) >> mixbits;
v[j] = l - r;
}
}
else
{
for ( j = 0; j < numSamples; j++ )
{
l = (int32_t)( ((uint32_t)ip[HBYTE] << 16) | ((uint32_t)ip[MBYTE] << 8) | (uint32_t)ip[LBYTE] );
l = (l << 8) >> 8;
ip += 3;
r = (int32_t)( ((uint32_t)ip[HBYTE] << 16) | ((uint32_t)ip[MBYTE] << 8) | (uint32_t)ip[LBYTE] );
r = (r << 8) >> 8;
ip += (stride - 1) * 3;
u[j] = (mixres * l + m2 * r) >> mixbits;
v[j] = l - r;
}
}
}
else
{
/* Conventional separated stereo. */
if ( bytesShifted != 0 )
{
for ( j = 0, k = 0; j < numSamples; j++, k += 2 )
{
l = (int32_t)( ((uint32_t)ip[HBYTE] << 16) | ((uint32_t)ip[MBYTE] << 8) | (uint32_t)ip[LBYTE] );
l = (l << 8) >> 8;
ip += 3;
r = (int32_t)( ((uint32_t)ip[HBYTE] << 16) | ((uint32_t)ip[MBYTE] << 8) | (uint32_t)ip[LBYTE] );
r = (r << 8) >> 8;
ip += (stride - 1) * 3;
shiftUV[k + 0] = (uint16_t)(l & mask);
shiftUV[k + 1] = (uint16_t)(r & mask);
l >>= shift;
r >>= shift;
u[j] = l;
v[j] = r;
}
}
else
{
for ( j = 0; j < numSamples; j++ )
{
l = (int32_t)( ((uint32_t)ip[HBYTE] << 16) | ((uint32_t)ip[MBYTE] << 8) | (uint32_t)ip[LBYTE] );
u[j] = (l << 8) >> 8;
ip += 3;
r = (int32_t)( ((uint32_t)ip[HBYTE] << 16) | ((uint32_t)ip[MBYTE] << 8) | (uint32_t)ip[LBYTE] );
v[j] = (r << 8) >> 8;
ip += (stride - 1) * 3;
}
}
}
}
// 32-bit routines
// - note that these really expect the internal data width to be < 32 but the arrays are 32-bit
// - otherwise, the calculations might overflow into the 33rd bit and be lost
// - therefore, these routines deal with the specified "unused lower" bytes in the "shift" buffers
void mix32( int32_t * in, uint32_t stride, int32_t * u, int32_t * v, int32_t numSamples,
int32_t mixbits, int32_t mixres, uint16_t * shiftUV, int32_t bytesShifted )
{
int32_t * ip = in;
int32_t shift = bytesShifted * 8;
uint32_t mask = (1ul << shift) - 1;
int32_t l, r;
int32_t j, k;
if ( mixres != 0 )
{
int32_t mod = 1 << mixbits;
int32_t m2;
//Assert( bytesShifted != 0 );
/* matrixed stereo with shift */
m2 = mod - mixres;
for ( j = 0, k = 0; j < numSamples; j++, k += 2 )
{
l = ip[0];
r = ip[1];
ip += stride;
shiftUV[k + 0] = (uint16_t)(l & mask);
shiftUV[k + 1] = (uint16_t)(r & mask);
l >>= shift;
r >>= shift;
u[j] = (mixres * l + m2 * r) >> mixbits;
v[j] = l - r;
}
}
else
{
if ( bytesShifted == 0 )
{
/* de-interleaving w/o shift */
for ( j = 0; j < numSamples; j++ )
{
u[j] = ip[0];
v[j] = ip[1];
ip += stride;
}
}
else
{
/* de-interleaving with shift */
for ( j = 0, k = 0; j < numSamples; j++, k += 2 )
{
l = ip[0];
r = ip[1];
ip += stride;
shiftUV[k + 0] = (uint16_t)(l & mask);
shiftUV[k + 1] = (uint16_t)(r & mask);
l >>= shift;
r >>= shift;
u[j] = l;
v[j] = r;
}
}
}
}
// 20/24-bit <-> 32-bit helper routines (not really matrixing but convenient to put here)
void copy20ToPredictor( uint8_t * in, uint32_t stride, int32_t * out, int32_t numSamples )
{
uint8_t * ip = in;
int32_t j;
for ( j = 0; j < numSamples; j++ )
{
int32_t val;
// 20-bit values are left-aligned in the 24-bit input buffer but right-aligned in the 32-bit output buffer
val = (int32_t)( ((uint32_t)ip[HBYTE] << 16) | ((uint32_t)ip[MBYTE] << 8) | (uint32_t)ip[LBYTE] );
out[j] = (val << 8) >> 12;
ip += stride * 3;
}
}
void copy24ToPredictor( uint8_t * in, uint32_t stride, int32_t * out, int32_t numSamples )
{
uint8_t * ip = in;
int32_t j;
for ( j = 0; j < numSamples; j++ )
{
int32_t val;
val = (int32_t)( ((uint32_t)ip[HBYTE] << 16) | ((uint32_t)ip[MBYTE] << 8) | (uint32_t)ip[LBYTE] );
out[j] = (val << 8) >> 8;
ip += stride * 3;
}
}

80
alac/codec/matrixlib.h Normal file
View file

@ -0,0 +1,80 @@
/*
* Copyright (c) 2011 Apple Inc. All rights reserved.
*
* @APPLE_APACHE_LICENSE_HEADER_START@
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* @APPLE_APACHE_LICENSE_HEADER_END@
*/
/*
File: matrixlib.h
Contains: ALAC mixing/matrixing routines to/from 32-bit predictor buffers.
Copyright: Copyright (C) 2004 to 2011 Apple, Inc.
*/
#ifndef __MATRIXLIB_H
#define __MATRIXLIB_H
#pragma once
#include <stdint.h>
#ifdef __cplusplus
extern "C" {
#endif
// 16-bit routines
void mix16( int16_t * in, uint32_t stride, int32_t * u, int32_t * v, int32_t numSamples, int32_t mixbits, int32_t mixres );
void unmix16( int32_t * u, int32_t * v, int16_t * out, uint32_t stride, int32_t numSamples, int32_t mixbits, int32_t mixres );
// 20-bit routines
void mix20( uint8_t * in, uint32_t stride, int32_t * u, int32_t * v, int32_t numSamples, int32_t mixbits, int32_t mixres );
void unmix20( int32_t * u, int32_t * v, uint8_t * out, uint32_t stride, int32_t numSamples, int32_t mixbits, int32_t mixres );
// 24-bit routines
// - 24-bit data sometimes compresses better by shifting off the bottom byte so these routines deal with
// the specified "unused lower bytes" in the combined "shift" buffer
void mix24( uint8_t * in, uint32_t stride, int32_t * u, int32_t * v, int32_t numSamples,
int32_t mixbits, int32_t mixres, uint16_t * shiftUV, int32_t bytesShifted );
void unmix24( int32_t * u, int32_t * v, uint8_t * out, uint32_t stride, int32_t numSamples,
int32_t mixbits, int32_t mixres, uint16_t * shiftUV, int32_t bytesShifted );
// 32-bit routines
// - note that these really expect the internal data width to be < 32-bit but the arrays are 32-bit
// - otherwise, the calculations might overflow into the 33rd bit and be lost
// - therefore, these routines deal with the specified "unused lower" bytes in the combined "shift" buffer
void mix32( int32_t * in, uint32_t stride, int32_t * u, int32_t * v, int32_t numSamples,
int32_t mixbits, int32_t mixres, uint16_t * shiftUV, int32_t bytesShifted );
void unmix32( int32_t * u, int32_t * v, int32_t * out, uint32_t stride, int32_t numSamples,
int32_t mixbits, int32_t mixres, uint16_t * shiftUV, int32_t bytesShifted );
// 20/24/32-bit <-> 32-bit helper routines (not really matrixing but convenient to put here)
void copy20ToPredictor( uint8_t * in, uint32_t stride, int32_t * out, int32_t numSamples );
void copy24ToPredictor( uint8_t * in, uint32_t stride, int32_t * out, int32_t numSamples );
void copyPredictorTo24( int32_t * in, uint8_t * out, uint32_t stride, int32_t numSamples );
void copyPredictorTo24Shift( int32_t * in, uint16_t * shift, uint8_t * out, uint32_t stride, int32_t numSamples, int32_t bytesShifted );
void copyPredictorTo20( int32_t * in, uint8_t * out, uint32_t stride, int32_t numSamples );
void copyPredictorTo32( int32_t * in, int32_t * out, uint32_t stride, int32_t numSamples );
void copyPredictorTo32Shift( int32_t * in, uint16_t * shift, int32_t * out, uint32_t stride, int32_t numSamples, int32_t bytesShifted );
#ifdef __cplusplus
}
#endif
#endif /* __MATRIXLIB_H */