private void ReduceBitsPerSample24Ns2(ConvertParams args, DataSubChunk toDsc)
{
var ns = new NoiseShaper2[mFsc.numChannels];
for (int ch = 0; ch < mFsc.numChannels; ++ch)
{
ns[ch] = new NoiseShaper2(args.order, args.filter, args.newQuantizationBitrate);
}
int bytesPerFrame = mFsc.numChannels * mFsc.bitsPerSample / 8;
int numFrames = toDsc.data.Length / bytesPerFrame;
int readPos = 0;
int writePos = 0;
for (int i = 0; i < numFrames; ++i)
{
for (int ch = 0; ch < mFsc.numChannels; ++ch)
{
int sample = 0;
sample = ns[ch].Filter24(ReadSampleValue24(toDsc, readPos));
readPos += mFsc.bitsPerSample / 8;
WriteSampleValue24(toDsc, writePos, sample);
writePos += mFsc.bitsPerSample / 8;
}
}
}
public void Convert(ConvertParams args, BinaryWriter bw)
{
var toDsc = new DataSubChunk();
toDsc.Setup(mDsc.subChunk2Size, mDsc.data);
switch (args.ditherType) {
case ConvertParams.DitherType.NoiseShaping:
args.order = 1;
args.filter = new double[] {1, -1};
ReduceBitsPerSample24Ns2(args, toDsc);
break;
case ConvertParams.DitherType.NoiseShaping2:
args.order = 2;
args.filter = new double[] {1, -2, 1};
ReduceBitsPerSample24Ns2(args, toDsc);
break;
case ConvertParams.DitherType.NoiseShapingMash2:
ReduceBitsPerSample24Mash2(args, toDsc);
break;
default:
ReduceBitsPerSample24Other(args, toDsc);
break;
}
mRcd.Write(bw);
mFsc.Write(bw);
toDsc.Write(bw);
}
public void Convert(ConvertParams args, BinaryWriter bw)
{
var toDsc = new DataSubChunk();
toDsc.Setup(mDsc.subChunk2Size, mDsc.data);
switch (args.ditherType)
{
case ConvertParams.DitherType.NoiseShaping:
args.order = 1;
args.filter = new double[] { 1, -1 };
ReduceBitsPerSample24Ns2(args, toDsc);
break;
case ConvertParams.DitherType.NoiseShaping2:
args.order = 2;
args.filter = new double[] { 1, -2, 1 };
ReduceBitsPerSample24Ns2(args, toDsc);
break;
case ConvertParams.DitherType.NoiseShapingMash2:
ReduceBitsPerSample24Mash2(args, toDsc);
break;
default:
ReduceBitsPerSample24Other(args, toDsc);
break;
}
mRcd.Write(bw);
mFsc.Write(bw);
toDsc.Write(bw);
}
private int ReadSampleValue24(DataSubChunk fromDsc, int pos)
{
switch (mFsc.bitsPerSample)
{
case 16:
return(256 * fromDsc.GetSampleValue16(pos));
case 24:
return(fromDsc.GetSampleValue24(pos));
default:
throw new NotImplementedException();
}
}
private void WriteSampleValue24(DataSubChunk toDsc, int pos, int value24)
{
switch (mFsc.bitsPerSample)
{
case 16:
toDsc.SetSampleValue16(pos, (short)(value24 / 256));
break;
case 24:
toDsc.SetSampleValue24(pos, value24);
break;
default:
throw new NotImplementedException();
}
}
public bool ReadFromFile(BinaryReader br)
{
mRcd = null;
mFsc = null;
mDsc = null;
try {
while (true)
{
var subChunk1Id = br.ReadInt32();
switch (subChunk1Id)
{
case ((int)('R')) + (((int)('I')) << 8) + (((int)('F')) << 16) + (((int)('F')) << 24):
mRcd = new RiffChunkDescriptor();
if (!mRcd.Read(br))
{
return(false);
}
break;
case ((int)('f')) + (((int)('m')) << 8) + (((int)('t')) << 16) + (((int)(' ')) << 24):
mFsc = new FmtSubChunk();
if (!mFsc.Read(br))
{
return(false);
}
break;
case ((int)('d')) + (((int)('a')) << 8) + (((int)('t')) << 16) + (((int)('a')) << 24):
mDsc = new DataSubChunk();
if (!mDsc.Read(br))
{
return(false);
}
break;
default:
SkipUnknownChunk(br);
break;
}
}
} catch (EndOfStreamException ex) {
// 正常終了ｗｗｗｗ
}
return(mRcd != null && mFsc != null && mDsc != null);
}
private void ReduceBitsPerSample24Mash2(ConvertParams args, DataSubChunk toDsc)
{
var mash = new NoiseShaperMash[mFsc.numChannels];
for (int ch = 0; ch < mFsc.numChannels; ++ch)
{
mash[ch] = new NoiseShaperMash(args.newQuantizationBitrate);
}
int bytesPerFrame = mFsc.numChannels * mFsc.bitsPerSample / 8;
int numFrames = toDsc.data.Length / bytesPerFrame;
int readPos = 0;
int writePos = 0;
// 1サンプル遅延するので…。
for (int i = 0; i < numFrames + 1; ++i)
{
for (int ch = 0; ch < mFsc.numChannels; ++ch)
{
int sample = 0;
if (i < numFrames)
{
sample = mash[ch].Filter24(ReadSampleValue24(toDsc, readPos));
readPos += mFsc.bitsPerSample / 8;
}
else
{
sample = mash[ch].Filter24(0);
}
if (1 <= i)
{
WriteSampleValue24(toDsc, writePos, sample);
writePos += mFsc.bitsPerSample / 8;
}
}
}
}
public bool ReadFromFile(BinaryReader br)
{
mRcd = null;
mFsc = null;
mDsc = null;
try {
while (true) {
var subChunk1Id = br.ReadInt32();
switch (subChunk1Id) {
case ((int)('R')) + (((int)('I')) << 8) + (((int)('F')) << 16) + (((int)('F')) << 24):
mRcd = new RiffChunkDescriptor();
if (!mRcd.Read(br)) {
return false;
}
break;
case ((int)('f')) + (((int)('m')) << 8) + (((int)('t')) << 16) + (((int)(' ')) << 24):
mFsc = new FmtSubChunk();
if (!mFsc.Read(br)) {
return false;
}
break;
case ((int)('d')) + (((int)('a')) << 8) + (((int)('t')) << 16) + (((int)('a')) << 24):
mDsc = new DataSubChunk();
if (!mDsc.Read(br)) {
return false;
}
break;
default:
SkipUnknownChunk(br);
break;
}
}
} catch (EndOfStreamException ex) {
// 正常終了ｗｗｗｗ
}
return mRcd != null && mFsc != null && mDsc != null;
}
private void ReduceBitsPerSample24Other(ConvertParams args, DataSubChunk toDsc)
{
uint mask = 0xffffffff << (24 - args.newQuantizationBitrate);
uint maskError = ~mask;
var gen = new RNGCryptoServiceProvider();
var gng = new GaussianNoiseGenerator();
var randomNumber = new byte[3];
int noiseMagnitude = (int)Math.Pow(2, (24 - args.newQuantizationBitrate)) / 2;
Console.WriteLine("D: maskErr={0:X}", maskError);
int bytesPerFrame = mFsc.numChannels * mFsc.bitsPerSample / 8;
int numFrames = toDsc.data.Length / bytesPerFrame;
int pos = 0;
for (int i = 0; i < numFrames; ++i)
{
for (int ch = 0; ch < mFsc.numChannels; ++ch)
{
double sample = ReadSampleValue24(toDsc, pos);
uint error = (uint)sample & maskError;
sample -= error;
switch (args.ditherType)
{
case ConvertParams.DitherType.Truncate:
break;
case ConvertParams.DitherType.RpdfDither:
gen.GetBytes(randomNumber);
int randDither = (int)((randomNumber[0]) + (randomNumber[1] << 8) + (randomNumber[2] << 16) & ~mask);
sample += randDither;
break;
case ConvertParams.DitherType.GaussianDither:
float noise = gng.NextFloat();
noise *= noiseMagnitude;
sample += (int)noise;
break;
default:
System.Diagnostics.Debug.Assert(false);
break;
}
if (0x7fffff < sample)
{
sample = 0x7fffff;
}
if (sample < -0x800000)
{
sample = -0x800000;
}
WriteSampleValue24(toDsc, pos, (int)sample);
pos += mFsc.bitsPerSample / 8;
}
}
}
private int ReadSampleValue24(DataSubChunk fromDsc, int pos)
{
switch (mFsc.bitsPerSample) {
case 16:
return 256 * fromDsc.GetSampleValue16(pos);
case 24:
return fromDsc.GetSampleValue24(pos);
default:
throw new NotImplementedException();
}
}
private void WriteSampleValue24(DataSubChunk toDsc, int pos, int value24)
{
switch (mFsc.bitsPerSample) {
case 16:
toDsc.SetSampleValue16(pos, (short)(value24 / 256));
break;
case 24:
toDsc.SetSampleValue24(pos, value24);
break;
default:
throw new NotImplementedException();
}
}
private void ReduceBitsPerSample24Other(ConvertParams args, DataSubChunk toDsc)
{
uint mask = 0xffffffff << (24 - args.newQuantizationBitrate);
uint maskError = ~mask;
var gen = new RNGCryptoServiceProvider();
var gng = new GaussianNoiseGenerator();
var randomNumber = new byte[3];
int noiseMagnitude = (int)Math.Pow(2, (24 - args.newQuantizationBitrate))/2;
Console.WriteLine("D: maskErr={0:X}", maskError);
int bytesPerFrame = mFsc.numChannels * mFsc.bitsPerSample / 8;
int numFrames = toDsc.data.Length / bytesPerFrame;
int pos = 0;
for (int i=0; i < numFrames; ++i) {
for (int ch=0; ch < mFsc.numChannels; ++ch) {
double sample = ReadSampleValue24(toDsc, pos);
uint error = (uint)sample & maskError;
sample -= error;
switch (args.ditherType) {
case ConvertParams.DitherType.Truncate:
break;
case ConvertParams.DitherType.RpdfDither:
gen.GetBytes(randomNumber);
int randDither = (int)((randomNumber[0]) + (randomNumber[1] << 8) + (randomNumber[2]<<16) & ~mask);
sample += randDither;
break;
case ConvertParams.DitherType.GaussianDither:
float noise = gng.NextFloat();
noise *= noiseMagnitude;
sample += (int)noise;
break;
default:
System.Diagnostics.Debug.Assert(false);
break;
}
if (0x7fffff < sample) {
sample = 0x7fffff;
}
if (sample < -0x800000) {
sample = -0x800000;
}
WriteSampleValue24(toDsc, pos, (int)sample);
pos += mFsc.bitsPerSample / 8;
}
}
}
private void ReduceBitsPerSample24Ns2(ConvertParams args, DataSubChunk toDsc)
{
var ns = new NoiseShaper2[mFsc.numChannels];
for (int ch=0; ch < mFsc.numChannels; ++ch) {
ns[ch] = new NoiseShaper2(args.order, args.filter, args.newQuantizationBitrate);
}
int bytesPerFrame = mFsc.numChannels * mFsc.bitsPerSample / 8;
int numFrames = toDsc.data.Length / bytesPerFrame;
int readPos = 0;
int writePos = 0;
for (int i=0; i < numFrames; ++i) {
for (int ch=0; ch < mFsc.numChannels; ++ch) {
int sample = 0;
sample = ns[ch].Filter24(ReadSampleValue24(toDsc, readPos));
readPos += mFsc.bitsPerSample / 8;
WriteSampleValue24(toDsc, writePos, sample);
writePos += mFsc.bitsPerSample / 8;
}
}
}
private void ReduceBitsPerSample24Mash2(ConvertParams args, DataSubChunk toDsc)
{
var mash = new NoiseShaperMash[mFsc.numChannels];
for (int ch=0; ch < mFsc.numChannels; ++ch) {
mash[ch] = new NoiseShaperMash(args.newQuantizationBitrate);
}
int bytesPerFrame = mFsc.numChannels * mFsc.bitsPerSample / 8;
int numFrames = toDsc.data.Length / bytesPerFrame;
int readPos = 0;
int writePos = 0;
// 1サンプル遅延するので…。
for (int i=0; i < numFrames + 1; ++i) {
for (int ch=0; ch < mFsc.numChannels; ++ch) {
int sample = 0;
if (i < numFrames) {
sample = mash[ch].Filter24(ReadSampleValue24(toDsc, readPos));
readPos += mFsc.bitsPerSample / 8;
} else {
sample = mash[ch].Filter24(0);
}
if (1 <= i) {
WriteSampleValue24(toDsc, writePos, sample);
writePos += mFsc.bitsPerSample / 8;
}
}
}
}
