int[] ProcessVerbatimSubframe( FlacBitReader bitReader, int bitsPerSample, int blockSize )
{
int[] data = new int[blockSize];
for( int i = 0; i < data.Length; i++ ) {
data[i] = bitReader.ReadSignedBits( bitsPerSample );
}
return data;
}
int[] ProcessFixedSubframe( FlacBitReader bitReader, int bitsPerSample, int predictorOrder, int blockSize )
{
int[] warmUpSamples = new int[predictorOrder];
for( int i = 0; i < predictorOrder; i++ ) {
warmUpSamples[i] = bitReader.ReadSignedBits( bitsPerSample );
}
int[] residual = ReadResidual( bitReader, predictorOrder, blockSize );
int[] data = new int[blockSize];
Buffer.BlockCopy( warmUpSamples, 0, data, 0, predictorOrder * sizeof( int ) );
FixedSignalRestore( residual, blockSize - predictorOrder, predictorOrder, data );
return data;
}
int[] ProcessLpcSubframe( FlacBitReader bitReader, int bitsPerSample, int lpcOrder, int blockSize )
{
int[] warmUpSamples = new int[lpcOrder];
for( int i = 0; i < warmUpSamples.Length; i++ ) {
warmUpSamples[i] = bitReader.ReadSignedBits( bitsPerSample );
}
int lpcPrecision = bitReader.ReadBits( 4 ) + 1;
if( lpcPrecision == 16 ) {// 1111 + 1
throw new InvalidDataException( "Invalid lpc precision." );
}
int lpcShift = bitReader.ReadSignedBits( 5 );
int[] coefficients = new int[lpcOrder];
for( int i = 0; i < coefficients.Length; i++ ) {
coefficients[i] = bitReader.ReadSignedBits( lpcPrecision );
}
int[] residual = ReadResidual( bitReader, lpcOrder, blockSize );
int[] data = new int[lpcOrder + blockSize];
Buffer.BlockCopy( warmUpSamples, 0, data, 0, lpcOrder * sizeof( int ) );
if( bitsPerSample + lpcPrecision + ilog2( lpcOrder ) <= 32 ) {
LpcRestoreSignal( residual, blockSize - lpcOrder, coefficients, lpcOrder, lpcShift, data );
} else {
LpcRestoreSignal64( residual, blockSize - lpcOrder, coefficients, lpcOrder, lpcShift, data );
}
return data;
}
int[] ProcessConstantSubframe( FlacBitReader bitReader, int bitsPerSample, int blockSize )
{
int constantValue = bitReader.ReadSignedBits( bitsPerSample );
int[] data = new int[blockSize];
for( int i = 0; i < data.Length; i++ ) {
data[i] = constantValue;
}
return data;
}