color space - OpenCV Display Colored Cb Cr Channels -


so understand how convert bgr image ycrcb format using cvtcolor() , seperate different channels using split() or mixchannels() in opencv. however, these channels displayed grayscale images cv_8uc1 mats.

i display cb , cr channels in color barns image on wikipedia. found solution in matlab, how do in opencv?

furthermore, mentioned solution displayed cb , cr channels "fills other channels constant value of 50%". question is:

is common way display cr cb channels? or there recommendations or specifications when displaying cr cb channels?

i made code scratch described in answer. looks it's need.

mat bgr_image = imread("lena.png");  mat ycrcb_image; cvtcolor(bgr_image, ycrcb_image, cv_bgr2ycrcb);  mat ycrcbchannels[3]; split(ycrcb_image, ycrcbchannels);  mat half(ycrcbchannels[0].size(), ycrcbchannels[0].type(), 127); vector<mat> ychannels = { ycrcbchannels[0], half, half }; mat yplot; merge(ychannels, yplot); cvtcolor(yplot, yplot, cv_ycrcb2bgr); imshow("y", yplot);  vector<mat> crchannels = { half, ycrcbchannels[1], half }; mat crplot; merge(crchannels, crplot); cvtcolor(crplot, crplot, cv_ycrcb2bgr); imshow("cr", crplot);  vector<mat> cbchannels = { half, half, ycrcbchannels[2] }; mat cbplot; merge(cbchannels, cbplot); cvtcolor(crplot, crplot, cv_ycrcb2bgr); imshow("cb", cbplot); waitkey(0);

enter image description here

as converting grayscale images color format, in such case color channels (b, g, r) set 1 grayscale value. in opencv cv_gray2bgr mode implemented in manner.

as "fills other channels constant value of 50%" believe it's common way visualize such color spaces ycbcr , lab. did not find articles , descriptions of approach, think it's driven visualization purposes. indeed, if fill other channels zero, fundamentally nothing has changed: can see influence of each channel, picture not nice:

enter image description here

so, aim of approach make visualization more colorful.


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