// ------------------------------------------------------
// helper function - sort list - FIXME: ugly, expensive: do something better
static void sort(ref List <int> l)
{
int [] tmp = new int[l.Count];
for (int i = 0; i < l.Count; i++)
{
tmp[i] = (l[i]);
}
Sort.RadixSort rs = new Sort.RadixSort();
rs.Sort(tmp);
l.Clear();
for (int i = 0; i < (int)tmp.Length; i++)
{
l.Add(tmp[i]);
}
}
public Quantizer(MultiDimFloatTexture tex, int qbits, float percent)
{
Globals.Assert(percent > 0.0f && percent <= 100.0f);
ScopeTimer tm = new ScopeTimer("[Quantizer]");
m_Texture = tex;
m_Quantized = new MultiDimIntTexture(tex.width(), tex.height(), tex.numComp());
m_iQBits = qbits;
m_Mean = new float[tex.numComp()];
m_StdDev = new float[tex.numComp()];
m_Center = new float[tex.numComp()];
m_Radius = new float[tex.numComp()];
// . compute std dev and mean of every components
float [] sum = new float[tex.numComp()];
float [] sumsq = new float[tex.numComp()];
for (int j = 0; j < tex.height(); j++)
{
for (int i = 0; i < tex.width(); i++)
{
for (int c = 0; c < tex.numComp(); c++)
{
float f = tex.get(i, j, c);
sum[c] += f;
sumsq[c] += f * f;
}
}
}
float num = (float)(tex.width() * tex.height());
for (int c = 0; c < tex.numComp(); c++)
{
m_Mean[c] = sum[c] / num;
float sqstddev = (sumsq[c] - sum[c] * sum[c] / num) / (num - 1.0f);
if (sqstddev > BMathLib.cFloatCompareEpsilon)
{
m_StdDev[c] = (float)Math.Sqrt(sqstddev);
}
else
{
m_StdDev[c] = 0.0f;
}
}
// . for every component
// compute center and radius so that 'percent' samples are within quantization space
for (int c = 0; c < tex.numComp(); c++)
{
float [] samples = new float[tex.width() * tex.height()];
// add samples to array
for (int j = 0; j < tex.height(); j++)
{
for (int i = 0; i < tex.width(); i++)
{
samples[i + j * tex.width()] = tex.get(i, j, c);
}
}
// sort array
Sort.RadixSort rs = new Sort.RadixSort();
rs.Sort(samples);//sort(samples.begin(),samples.end());
// find left and right elements so that 'percent' elements are inside
float pout = ((100.0f - percent) / 2) / 100.0f;
int left = (int)((samples.Length - 1) * pout);
int right = (int)((samples.Length - 1) * (1.0f - pout));
m_Center[c] = (samples[right] + samples[left]) / 2.0f;
m_Radius[c] = samples[right] - samples[left];
}
// . quantize
int num_outside = 0;
for (int j = 0; j < tex.height(); j++)
{
for (int i = 0; i < tex.width(); i++)
{
if (!quantizePixel(tex.numComp(), tex, tex.getpixIndex(i, j), m_Quantized.getpixIndex(i, j)))
{
num_outside++;
}
}
}
float percent_out = num_outside * 100.0f / (tex.width() * tex.height());
if (Globals.PRINT_DEBUG_MSG)
{
Debug.Print("-----------.>> Quantizer: num outside = " + percent_out + "%");
}
tm.destroy();
tm = null;
}