kiock,
If you want to know about histogram method, please search “contrast(histogram) stretching” and “histogram equaliztion”. You will have many resources from the net.
Adjusting brightness and contrast is very easy as I described in the previous post, so you can easily implement into your program. Just watch out min and max values of the data type.
I can give you the source code of above example. Let me know if you are interested in.
Programs like Paint Shop Pro have a tool to increase the gamma. This is much better than
just increasing the brightness of every pixel. I think it is very easy to do. A gamma
table (256 values for each R,G,B component, so 256*3 total entries) is first calculated
for some given gamma value, say, 1.5, then every pixel is replaced with its gamma
table value entry. You can probably find some code on Google.
Hi,
I have created shader for brightness in QT, also I have draw an Image on shader but actualy my problem is how i will update the brightness value in Image??
Iam new User Of OpenGl Shader so rely Iam not getting any idea…
Please Reply me soon…