public unsafe void writeints(int len, int pos, byte *buf)
{
int old_pos = BitLength;
int start = old_pos / 8;
int start1 = pos / 8;
int end = (old_pos + len) / 8;
int end1 = (pos + len) / 8;
flush();
byte start_val = old_pos % 8 != 0 ? buffer[start] : (byte)0;
fixed(byte *buf1 = &buffer[0])
{
if (old_pos % 8 != 0)
{
crc16_m = Crc16.Substract(crc16_m, 0, 1);
}
crc16_m = Crc16.ComputeChecksum(crc16_m, buf + start1, end - start);
AudioSamples.MemCpy(buf1 + start, buf + start1, end - start);
buf1[start] |= start_val;
}
buf_ptr_m = end;
if ((old_pos + len) % 8 != 0)
{
writebits((old_pos + len) % 8, buf[end1] >> (8 - ((old_pos + len) % 8)));
}
}
unsafe void fill_frames_buffer()
{
if (_framesBufferLength == 0)
{
_framesBufferOffset = 0;
}
else if (_framesBufferLength < _framesBuffer.Length / 2 && _framesBufferOffset >= _framesBuffer.Length / 2)
{
fixed(byte *buff = _framesBuffer)
AudioSamples.MemCpy(buff, buff + _framesBufferOffset, _framesBufferLength);
_framesBufferOffset = 0;
}
long readCount = 0;
while (_framesBufferLength < _framesBuffer.Length / 2)
{
readCount++;
int read = _IO.Read(_framesBuffer, _framesBufferOffset + _framesBufferLength, _framesBuffer.Length - _framesBufferOffset - _framesBufferLength);
_framesBufferLength += read;
if (read == 0)
{
break;
}
}
}
unsafe void Restore_samples_fixed(FlacFrame frame, int ch)
{
FlacSubframeInfo sub = frame.subframes[ch];
AudioSamples.MemCpy(sub.samples, sub.best.residual, sub.best.order);
int *data = sub.samples + sub.best.order;
int *residual = sub.best.residual + sub.best.order;
int data_len = frame.blocksize - sub.best.order;
int s0, s1, s2;
switch (sub.best.order)
{
case 0:
AudioSamples.MemCpy(data, residual, data_len);
break;
case 1:
s1 = data[-1];
for (int i = data_len; i > 0; i--)
{
s1 += *(residual++);
*(data++) = s1;
}
//data[i] = residual[i] + data[i - 1];
break;
case 2:
s2 = data[-2];
s1 = data[-1];
for (int i = data_len; i > 0; i--)
{
s0 = *(residual++) + (s1 << 1) - s2;
*(data++) = s0;
s2 = s1;
s1 = s0;
}
//data[i] = residual[i] + data[i - 1] * 2 - data[i - 2];
break;
case 3:
for (int i = 0; i < data_len; i++)
{
data[i] = residual[i] + (((data[i - 1] - data[i - 2]) << 1) + (data[i - 1] - data[i - 2])) + data[i - 3];
}
break;
case 4:
for (int i = 0; i < data_len; i++)
{
data[i] = residual[i] + ((data[i - 1] + data[i - 3]) << 2) - ((data[i - 2] << 2) + (data[i - 2] << 1)) - data[i - 4];
}
break;
}
}
unsafe void Restore_samples(FlacFrame frame)
{
for (int ch = 0; ch < PCM.ChannelCount; ch++)
{
switch (frame.subframes[ch].best.type)
{
case SubframeType.Constant:
AudioSamples.MemSet(frame.subframes[ch].samples, frame.subframes[ch].best.residual[0], frame.blocksize);
break;
case SubframeType.Verbatim:
AudioSamples.MemCpy(frame.subframes[ch].samples, frame.subframes[ch].best.residual, frame.blocksize);
break;
case SubframeType.Fixed:
Restore_samples_fixed(frame, ch);
break;
case SubframeType.LPC:
Restore_samples_lpc(frame, ch);
break;
}
if (frame.subframes[ch].wbits != 0)
{
int *s = frame.subframes[ch].samples;
int x = (int)frame.subframes[ch].wbits;
for (int i = frame.blocksize; i > 0; i--)
{
*(s++) <<= x;
}
}
}
if (frame.ch_mode != ChannelMode.NotStereo)
{
int *l = frame.subframes[0].samples;
int *r = frame.subframes[1].samples;
switch (frame.ch_mode)
{
case ChannelMode.LeftRight:
break;
case ChannelMode.MidSide:
for (int i = frame.blocksize; i > 0; i--)
{
int mid = *l;
int side = *r;
mid <<= 1;
mid |= (side & 1); /* i.e. if 'side' is odd... */
*(l++) = (mid + side) >> 1;
*(r++) = (mid - side) >> 1;
}
break;
case ChannelMode.LeftSide:
for (int i = frame.blocksize; i > 0; i--)
{
int _l = *(l++), _r = *r;
*(r++) = _l - _r;
}
break;
case ChannelMode.RightSide:
for (int i = frame.blocksize; i > 0; i--)
{
*(l++) += *(r++);
}
break;
}
}
}