Hi community

I just finished a new post about Gamma Correction.

https://nbertoa.wordpress.com/2016/06/20/gamma-correction/

Hi Alectora

Today all common image formats (GIF, JPEG, PNG, etc) are assumed to be in gamma space. This is typically 2.2. With Photoshop you can adjust gamma manually. I think most image files you will find in Internet are already gamma-corrected, so you should not worry about.

I feel like your first paragraph might be a bit misleading.

Proper gamma correction is probably the easiest, most inexpensive, and most widely applicable technique for improving image quality in real-time applications.

Gamma correction in itself will not magically improve the quality of your images. Gamma correction is purely a tool to make sure you do operations on your images in linear space, and doing operations in linear space does not guarantee a better looking image. As a stylistic choice it might be completely OK to disregard gamma correction at all, depending on the title. If you want to do any kind of physically based lighting however it's in your best interest to get linear values as input.

If you want more information, John Hable wrote a good amount of articles on gamma correction a couple of years ago which go very in depth on the subject: http://filmicgames.com/archives/category/gamma

I would recommend being careful when explaining what sRGB is. A lot of people are under the mistaken impression that it's just the transfer function (AKA the "gamma curve"), but being a RGB color space it also specifies the chromaticities of the primaries. So you can have the situation where perhaps you use the primaries but not the transfer function, which is what people are usually using when they refer to "linear" space. Or you can have other standards (like Rec. 709) that use the same primaries, but have a different transfer function. You generally don't have to worry about that until you need to work in another color space, and then things can get confusing if you don't understand what the color space is actually specifying.

@Radikalizm:

Gamma correction in itself will not magically improve the quality of your images. Gamma correction is purely a tool to make sure you do operations on your images in linear space, and doing operations in linear space does not guarantee a better looking image. As a stylistic choice it might be completely OK to disregard gamma correction at all, depending on the title. If you want to do any kind of physically based lighting however it's in your best interest to get linear values as input.

I agree with respect to It will not necessarily guarantee a better looking image, because you could did a lot of hacks with your lights parameters and count. Those hacks will be exposed when you change to a gamma-corrected approach. On the other hand, I think it will really increase "image quality" because you will see how things should be, and not things that were altered by monitor.

If you want more information, John Hable wrote a good amount of articles on gamma correction a couple of years ago which go very in depth on the subject: http://filmicgames.com/archives/category/gamma

Thanks for the links, I will read them

@MJP:

I would recommend being careful when explaining what sRGB is. A lot of people are under the mistaken impression that it's just the transfer function (AKA the "gamma curve"), but being a RGB color space it also specifies the chromaticities of the primaries. So you can have the situation where perhaps you use the primaries but not the transfer function, which is what people are usually using when they refer to "linear" space. Or you can have other standards (like Rec. 709) that use the same primaries, but have a different transfer function. You generally don't have to worry about that until you need to work in another color space, and then things can get confusing if you don't understand what the color space is actually specifying.

Thanks, I will take that into account

I just came across this excellent presentation that anyone should read if they're interested in color spaces and proper terminology.