topic need help for sepia in Intel® Integrated Performance Primitives

need help for sepia

tarifut — Mon, 16 Aug 2010 09:18:59 GMT

Hi everyone!

I don't know how to make sepia on a picture with opencv.I can't find any clue to make this.Could you help me?

Thanks

need help for sepia

Naveen_G_Intel — Tue, 17 Aug 2010 04:48:57 GMT

Hi,

Sepia on a picture is basically color conversion, Intel IPP has got several APIs for this type of operation, like Color models conversion, Gamma correction, Color twist, Color keying etc. I am sure you can use IPP for sepia on an image.

Sorry, I dont know how to do it using OpenCV, also this forum is intended for Intel IPP discussion, feel free to share your experience on using IPP for sepia.

Regards,

Naveen Gv

need help for sepia

Sergey_K_Intel — Tue, 17 Aug 2010 07:55:05 GMT

With the IPP you may do the following

// Convert RGB to gray
IppiSize roi;
roi.width = uiWidth;
roi.height = uiHeight;
status = ippiRGBToGray_8u_C3C1R((const Ipp8u*)uiInputImage, uiWidth*3, (Ipp8u*)pGrayImage, stepBytes, roi);

// Copy gray channels to color image
status = ippiDup_8u_C1C3R((const Ipp8u*)pGrayImage, stepBytes, (Ipp8u*)uiOutputImage, uiWidth*3, roi);

//Shift colors
const Ipp8u movColor[3] = { 162, 138, 101 };
status = ippiAddC_8u_C3IRSfs(movColor, (Ipp8u*)uiOutputImage, uiWidth*3, roi, 1);

Actually, sepia is

// Shift colors
unsigned int newR, newG, newB;
newR = (unsigned int)(R * 0.393 + G * 0.769 + B * 0.189); if (newR > 255) newR = 255;
newG = (unsigned int)(R * 0.349 + G * 0.686 + B * 0.168); if (newG > 255) newG = 255;
newB = (unsigned int)(R * 0.272 + G * 0.534 + B * 0.131); if (newB > 255) newB = 255;

need help for sepia

Vladimir_Dudnik — Tue, 17 Aug 2010 11:28:14 GMT

Note, we also provide an example of sepia transform within Deferred Mode Image Processing (DMIP) sample.

Regards,
Vladimir