Function calculateHistogram

Samples/NiViewer/Draw.cpp:548–596

}

void calculateHistogram()
{
	DepthGenerator* pDepthGen = getDepthGenerator();

	if (pDepthGen == NULL)
		return;

	XnUInt32 nZRes = pDepthGen->GetDeviceMaxDepth() + 1;
	if (g_pDepthHist == NULL)
	{
		g_pDepthHist = new float[nZRes];
	}

	xnOSMemSet(g_pDepthHist, 0, nZRes*sizeof(float));
	int nNumberOfPoints = 0;

	XnDepthPixel nValue;

	const XnDepthPixel* pDepth = pDepthGen->GetDepthMap();
	const XnDepthPixel* pDepthEnd = pDepth + (pDepthGen->GetDataSize() / sizeof(XnDepthPixel));

	while (pDepth != pDepthEnd)
	{
		nValue = *pDepth;

		XN_ASSERT(nValue <= nZRes);

		if (nValue != 0)
		{
			g_pDepthHist[nValue]++;
			nNumberOfPoints++;
		}

		pDepth++;
	}

	XnUInt32 nIndex;
	for (nIndex = 1; nIndex < nZRes; nIndex++)
	{
		g_pDepthHist[nIndex] += g_pDepthHist[nIndex-1];
	}
	for (nIndex = 1; nIndex < nZRes; nIndex++)
	{
		if (g_pDepthHist[nIndex] != 0)
		{
			g_pDepthHist[nIndex] = (nNumberOfPoints-g_pDepthHist[nIndex]) / nNumberOfPoints;
		}
	}
}

// --------------------------------
// Drawing