How to analyze a pseudo-color image by matlab?

Hello, masters, I need to analyze a pseudo-color image with matlab.This is the image: <http://s1151.photobucket.com/albums/o628/sevenshuixina/?action=view&current=000003.jpg> It's a photo of laser spot. I want to know the intensity of a pixel from its color. In other words, I want to make sure the grayscale or intensity of a pixel by its color. Then I will draw a 3D image of intensity-coordinate distribution. How can I do these？ Please, help me! Thanks!!!

EDIT DES: embedded image

[Jin Yuhua]

http://s1151.photobucket.com/albums/o628/sevenshuixina/?action=view&current=000003.jpg

Answer 1

[Walter Roberson]

This cannot be done unless you are given the color map.

If you are given the color map, then use ind2rgb() to create an rgb image, then rgb2gray(), and surf() the result.

[Jin Yuhua]

Heartfelt thanks. Can I get the color map from the color data on the right side of the image？Or, I have to get a real color map of this image？

—— http://s1151.photobucket.com/albums/o628/sevenshuixina/?action=view&current=1.jpg

[Walter Roberson]

Those two images are not pseudo-color: they are true-color. They are JPEG images, and JPEG is not able to store pseudo-color images.

The images are the truecolor versions of plots that were originally pseudo-color. It appears that the temperature was linearly extrapolated into a color table, ranging from 0 degrees to 4096 degrees. However, it appears that the color table was not arranged by hue (white is not a hue). The color table is similar to the "jet" colormap, except that "jet" ends in dark red, not in white.

You will need to obtain the original colormap, or else to attempt to rebuild it by using a color examiner and matching to the temperature table of "1.jpg".

Question: in physics, does intensity increase linearly with temperature? I'm still half asleep at the moment and thinking about Boltzmann distributions is too much right now.

[Jin Yuhua]

I was deeply moved by your answer, and you are so serious about my problem. I want to say thank you very much once again～^ ^ .I will try to obtain the original colormap, and try my best to solve this problem.

Ps: In physics , temperature not only have relationship with intensity, but also have relationship with time, irradiated area and specific heat. So I think it is not a simple linearly relationship.

Please take a good rest !

[Jin Yuhua]

Excuse me, master, I have obtained the original colormap. And I want to know how to import it. I obtained it from the software of spot photo processing . It is consisted of 128 colors. And the color matrix as follows:

40 0 60

50 0 70

60 0 80

70 0 85

80 0 90

95 0 100

105 0 110

115 0 115

125 0 115

140 0 115

155 0 115

170 0 115

185 0 115

200 0 125

210 0 135

220 0 150

220 0 180

205 0 200

205 0 230

190 0 255

170 0 255

150 0 255

130 0 255

110 0 255

80 0 255

40 0 255

0 0 255

0 0 245

0 0 235

0 0 225

0 0 215

0 0 205

0 35 205

0 50 205

0 65 205

0 80 205

0 95 205

0 105 210

0 115 220

0 125 225

0 125 235

0 135 240

0 145 250

0 155 255

0 170 255

0 185 255

0 195 255

0 210 255

0 230 255

0 245 255

0 255 235

0 255 220

0 255 180

0 255 140

0 255 80

0 255 0

0 240 0

0 235 0

0 230 0

0 225 0

0 220 0

0 215 0

0 210 0

0 205 0

0 200 0

0 195 0

0 190 0

30 195 0

35 200 0

40 205 0

50 210 0

70 215 0

90 220 0

118 225 0

137 230 0

156 234 0

174 238 0

191 241 0

207 245 0

221 248 0

233 250 0

242 252 0

249 254 0

254 255 0

255 255 0

255 254 0

255 252 0

255 249 0

255 244 0

255 238 0

255 231 0

255 223 0

255 215 0

255 206 0

255 196 0

255 187 0

255 177 0

255 168 0

255 160 0

255 152 0

255 145 0

255 139 0

255 134 0

255 131 0

255 129 0

255 128 0

255 127 0

255 125 0

255 122 0

255 117 0

255 111 0

255 104 0

255 96 0

255 87 0

255 78 0

255 69 0

255 59 0

255 50 0

255 41 0

255 32 0

255 24 0

255 17 0

255 11 0

255 6 0

255 3 0

255 1 0

255 0 0

255 0 0

http://s1151.photobucket.com/albums/o628/sevenshuixina/?action=view&current=colormap.jpg

Then, I want to know how to make this colormap import the matlab？

Thank you very much~!