how can i combine the L,a,b to make lab image?

i use RGB2lab function to convert RGB image to lab image i do this work by this to line code % cform = makecform('srgb2lab'); lab = applycform(mov(k).cdata,cform); but the output of this 2 way is different for example the value of pixels in lab(:,:,1) isnt between 0-100 i want to know the second way for convert is true? and after convert i need to rebuilt the image from l,a,b how can i do this? when i use cat[l,a,b] the output isnt true?!(RGB2lab is a function that i download from http://www.mathworks.com/matlabcentral/fileexchange/24009-rgb2lab

[Walter Roberson]

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Answer 1

[Image Analyst]

If I remember correctly applycform gives different ranges depending on if the image is floating point or integer. Try casting your image to double before converting to LAB and see if you get the correct ranges out. You might have to do it manually using makecform instead of using that File Exchange program.