private double EndiannessHeuristicValue(UShortAccess data, uint dataSize, ref uint maxSamples)
{
if (data == null)
{
return(50000); // the heuristic value for the wrong endianess is about 21000 (1/3rd of the 16 bits range)
}
double diff_sum = 0;
uint cpt = 0;
short prev_value = (short)data[0];
for (int i = 1; i < dataSize && cpt < maxSamples; ++i)
{
short value = (short)data[i];
if (value != prev_value)
{
diff_sum += Math.Abs((double)(value - prev_value));
++cpt;
prev_value = value;
}
}
if (cpt == 0)
{
return(50000);
}
maxSamples = cpt;
return(diff_sum / cpt);
}
public void LoadLiveList(UShortAccess src)
{
for (var cnt = 0; cnt < TOTAL_SECTIONS; cnt++)
{
if (_liveList[cnt] != 0)
{
_resMan.ResClose(_objectList[cnt]);
_cptData[cnt] = null;
}
_liveList[cnt] = src[cnt];
if (_liveList[cnt] != 0)
{
_cptData[cnt] = new ByteAccess(_resMan.CptResOpen(_objectList[cnt]), Header.Size);
}
}
}
private void CalcWaveVolume(UShortAccess data, int length)
{
var blkPos = new UShortAccess(data.Data, data.Offset + 918 * 2);
uint cnt;
for (cnt = 0; cnt < WAVE_VOL_TAB_LENGTH; cnt++)
{
_waveVolume[cnt] = false;
}
_waveVolPos = 0;
for (uint blkCnt = 1; blkCnt < length / 918; blkCnt++)
{
if (blkCnt >= WAVE_VOL_TAB_LENGTH)
{
// TODO: warning("Wave vol tab too small");
return;
}
int average = 0;
for (cnt = 0; cnt < 918; cnt++)
{
average += blkPos[(int)cnt];
}
average /= 918;
uint diff = 0;
for (cnt = 0; cnt < 918; cnt++)
{
short smpDiff = (short)(blkPos[0] - average);
diff += (uint)Math.Abs(smpDiff);
blkPos.Offset += 2;
}
if (diff > WAVE_VOL_THRESHOLD)
{
_waveVolume[blkCnt - 1] = true;
}
}
}
private UShortAccess UncompressSpeech(uint index, uint cSize, out uint size)
{
_cowFile.BaseStream.Seek(index, SeekOrigin.Begin);
var fBuf = _cowFile.ReadBytes((int)cSize);
uint headerPos = 0;
while ((fBuf.ToUInt32BigEndian((int)headerPos) != ScummHelper.MakeTag('d', 'a', 't', 'a')) && (headerPos < 100))
{
headerPos++;
}
UShortAccess srcData;
if (headerPos < 100)
{
int resSize;
uint srcPos;
short length;
cSize /= 2;
headerPos += 4; // skip 'data' tag
if (_cowMode != CowMode.CowDemo)
{
resSize = (int)(fBuf.ToUInt32((int)headerPos) >> 1);
headerPos += 4;
}
else
{
// the demo speech files have the uncompressed size
// embedded in the compressed stream *sigh*
//
// But not always, apparently. See bug #2182450. Is
// there any way to figure out the size other than
// decoding the sound in that case?
if (fBuf[headerPos + 1] == 0)
{
if (fBuf.ToInt16((int)headerPos) == 1)
{
resSize = fBuf.ToInt16((int)(headerPos + 2));
resSize |= fBuf.ToInt16((int)(headerPos + 6)) << 16;
}
else
{
resSize = fBuf.ToInt32((int)(headerPos + 2));
}
resSize >>= 1;
}
else
{
resSize = 0;
srcData = new UShortAccess(fBuf);
srcPos = headerPos >> 1;
while (srcPos < cSize)
{
length = (short)srcData[(int)srcPos];
srcPos++;
if (length < 0)
{
resSize -= length;
srcPos++;
}
else
{
resSize += length;
srcPos = (uint)(srcPos + length);
}
}
}
}
Debug.Assert((headerPos & 1) == 0);
srcData = new UShortAccess(fBuf);
srcPos = headerPos >> 1;
uint dstPos = 0;
var dstData = new UShortAccess(new byte[resSize * 2]);
int samplesLeft = resSize;
while (srcPos < cSize && samplesLeft > 0)
{
length = (short)(_bigEndianSpeech ? ScummHelper.SwapBytes(srcData[(int)srcPos]) : srcData[(int)srcPos]);
srcPos++;
if (length < 0)
{
length = (short)-length;
if (length > samplesLeft)
{
length = (short)samplesLeft;
}
short value;
if (_bigEndianSpeech)
{
value = (short)ScummHelper.SwapBytes(srcData[(int)srcPos]);
}
else
{
value = (short)srcData[(int)srcPos];
}
for (ushort cnt = 0; cnt < (ushort)length; cnt++)
{
dstData[(int)dstPos++] = (ushort)value;
}
srcPos++;
}
else
{
if (length > samplesLeft)
{
length = (short)samplesLeft;
}
if (_bigEndianSpeech)
{
for (ushort cnt = 0; cnt < length; cnt++)
{
dstData[(int)dstPos++] = ScummHelper.SwapBytes(srcData[(int)srcPos++]);
}
}
else
{
Array.Copy(srcData.Data, (int)(srcData.Offset + srcPos * 2), dstData.Data, (int)(dstData.Offset + dstPos * 2), length * 2);
dstPos = (uint)(dstPos + length);
srcPos = (uint)(srcPos + length);
}
}
samplesLeft -= length;
}
if (samplesLeft > 0)
{
dstData.Data.Set((int)(dstData.Offset + dstPos), 0, samplesLeft * 2);
}
if (_cowMode == CowMode.CowDemo) // demo has wave output size embedded in the compressed data
{
dstData.Data.WriteUInt32(dstData.Offset, 0);
}
size = (uint)(resSize * 2);
CalcWaveVolume(dstData, resSize);
return(dstData);
}
else
{
// TODO: warning("Sound::uncompressSpeech(): DATA tag not found in wave header");
size = 0;
return(null);
}
}