private void PrepareFixedSubframe(int order, int subframeBitsPerSample)
{
int[] warmupSamples = new int[order];
for (int i = 0; i < order; i++)
{
warmupSamples[i] = bitReader.ReadSignedBits(subframeBitsPerSample - this.wastedBitsPerSample);
}
IEnumerator <int> residual = ReadResidualData(bitReader, BlockSize, order);
IPredictor predictor = PredictorFactory.CreateFixedPredictor(order, RemoveLastItem(warmupSamples));
dataSource = GetPredictorSamples(BlockSize, warmupSamples, predictor, residual);
}
private FlacMethod FindBestFixedMethod(int[] channelSamples, int bitsPerSample, FlacEncodingPolicy policy)
{
if (!policy.FixedOrder.HasValue)
{
return(null);
}
int minFixedOrder = policy.FixedOrder.Value.MinValue;
int maxFixedOrder = Math.Min(channelSamples.Length - 1,
policy.FixedOrder.Value.MaxValue);
FlacMethod[] methods = new FlacMethod[maxFixedOrder + 1];
parallel.For(minFixedOrder, maxFixedOrder + 1, order =>
{
IPredictor predictor = PredictorFactory.CreateFixedPredictor(order, ArrayUtils.CutArray(channelSamples, 0, order - 1));
FlacResidualCoefficeints residual = FindBestResidual(channelSamples, order, predictor, policy);
FlacMethod method = new FlacFixedMethod(bitsPerSample, order, residual);
methods[order] = method;
});
return(FindBestMethod(methods));
}
internal override IPredictor CreatePredictor(int[] samples)
{
return(PredictorFactory.CreateFixedPredictor(Order, samples));
}