int[] ReadResidual( FlacBitReader bitReader, int predictorOrder, int blockSize )
{
int encodingMethod = bitReader.ReadBits( 2 );
if( !( encodingMethod == 0 || encodingMethod == 1 ) ) {
throw new InvalidDataException( "Invalid rice encoding method." );
}
bool extended = encodingMethod == 1;
int partitionOrder = bitReader.ReadBits( 4 );
int partitionsCount = 1 << partitionOrder; // 2^x.
int partitionSamples = partitionOrder > 0 ? blockSize >> partitionOrder : blockSize - predictorOrder;
int paramLength = extended ? rice2ParamLength : riceParamLength;
int escapeParam = extended ? rice2EscapeParam : riceEscapeParam;
int sample = 0;
int[] residual = new int[blockSize - predictorOrder];
for( int partition = 0; partition < partitionsCount; partition++ ) {
int riceParam = bitReader.ReadBits( paramLength );
if( riceParam < escapeParam ) {
int n = ( partitionOrder == 0 || partition > 0 ) ? partitionSamples : partitionSamples - predictorOrder;
for( int i = 0; i < n; i++ ) {
residual[sample + i] = bitReader.ReadRice( riceParam );
}
sample += n;
} else {
int rawParamLength = bitReader.ReadBits( riceEscapeParamLength );
int n = ( partitionOrder == 0 || partition > 0 ) ? partitionSamples : partitionSamples - predictorOrder;
for( int i = 0; i < n; i++ ) {
residual[sample + i] = bitReader.ReadBits( rawParamLength );
}
sample += n;
}
}
return residual;
}
