Showing Depth Data through a cv::Mat

[Marios_B_]

Hi guys!

I want to show to the user a Depth Image mapped to Color.I want to do this by using a cv::Mat.

I used the projection->CreateDepthImageMappedToColor(PXCImage *depth, PXCImage *color);

 p and I managed to pass the pxcimage data to a cv::Mat MappedDepthMat(480,640,CV_16UC1); by using the following function:

void CopyDepthImageMappedToColor_ToMat(PXCImage *ColorImage,PXCImage *DepthImage,PXCImage::ImageData &data,cv::Mat &MappedDepthMat)
{
	PXCImage* mapped=projection->CreateDepthImageMappedToColor(DepthImage,ColorImage);
	pxcStatus sts=mapped->AcquireAccess(PXCImage::ACCESS_READ,&data);
	if(sts==PXC_STATUS_NO_ERROR )
	{
		memcpy(MappedDepthMat.data,data.planes[0],sizeof(unsigned short) * 640 * 480);
		MappedDepthMat=MappedDepthMat*255;
		mapped->ReleaseAccess(&data);
	}

}

You can see that I multiply each element by 255.If I don't do this,then I get a black screen because of the Mat.The original values of MappedDepthMat before I multiply by 255 give me the distance in mm,correct? What is the maximum value?Can I somehow normalize the whole thing and have max depth=1 and min depth=0?

What is the original range?When I call the above mentioned function what is the max value of pixel?Can I somehow change the maximum value and still get the required result?

At the end of the day,I want to have a Mat with a range of 0-1 but with float values in between.I need this to match with the opengl's z-buffer values.

[Xusheng_L_Intel]

Could you change

pxcStatus sts=mapped->AcquireAccess(PXCImage::ACCESS_READ,&data);

to

pxcStatus sts=mapped->AcquireAccess(PXCImage::ACCESS_READ,PXCImage::PIXEL_FORMAT_DEPTH_F32, &data);

and let me know if you still have such issue. Thanks!

[x_c_]

Hi, This my code, it succeeeded, and maybe it will help you.  

   Mat depthimage8;   
    depthimage8.create(480,640,CV_8UC1); 

    PXCImage::ImageData data_depth;  unsigned short *depth_data;

              sample->depth->AcquireAccess(PXCImage::ACCESS_READ,PXCImage::PIXEL_FORMAT_DEPTH, &data_depth);   
                    depth_data = (unsigned short*)data_depth.planes[0];   
                    unsigned char cVal;
                    for(int y=0; y<H; y++)
                    {
                        for(int x=0; x<W; x++)
                        {
                            if(depth_data[y*W+x] >  fMaxValue)    //fMaxValue = 1000
                                depth_data[y*W+x] =  fMaxValue; 
                            cVal = (unsigned char)((1.0*depth_data[y*W+x])/fMaxValue*255); 
                            if(cVal!=0)
                                cVal = 255 - cVal;   
                            depthimage8.at<unsigned char>(y,x) = cVal;
                        }
                    }