MarioWiki:Proposals

Writing guidelines
None at the moment.

New Template:Gamma Image
An interesting oddity that I and few other users have noticed while dealing with images is a very interesting type of metadata called Gamma Brightening. In short, what gamma brightening does is change the way the colors of an image are displayed. This is generally very rare, but it is important as the differences between images is severely drastic. After some internal discussion, most notably with Steve, the unspoken policy course of action is to not optimize images with gamma brightening, and leave that metadata on the image if it is the way the source image provides the picture.

The purpose of the proposal is to make this unspoken policy a spoken policy. People should know when an image has a special property and should be treated differently.

The following template,, would be placed on the documented images with gamma brightening:  This image contains gamma brightening, and should not be optimized.

 This image contains gamma brightening, and should not be optimized.

Such images seen thus far is:
 * File:Hammer Bro-NSMBU.png
 * File:MP8 Hammer Bro Artwork.png
 * File:NSMBDS Goomba Artwork.png
 * File:BulletBillWii.png
 * File:NSMBDS Buzzy Beetle Artwork.png
 * File:NSMBW Mario Holding Green Shell Artwork.png
 * File:NSMBW Mario Jumping Artwork.png
 * File:Blueboostblock.png

It would also be suggested, but not required, to create a MarioWiki page discussing gamma brightening over using a section on my user page.

Comparison image:

Proposer:

Deadline: Feb 19, 2020, 23:59 GMT

Support (Create template)

 * 1) Per proposal
 * 2) per proposal
 * 3) - Per proposal.
 * 4) - It might be odd seeing this on many image pages, but otherwise it is a reasonable decision. We want to preserve the original nature of the image as much we can. Although personally I prefer the Gamma brightness removed for the Hammer Bro pic but just in this case, and it's only my opinion.
 * 5) I’m still wondering if removing metadata doesn’t create more problems than it solves (it’s often a few bytes of data where the IDAT chunk is orders of magnitude bigger), but since current optimization software removes them and since the gAMA chunk definitely must not be removed, it’s better to add this template.
 * 6) Per all.

Comments
I mentioned you could simply say this information in the aboutfile template. Because of that, I don't see a need for this template, as it would only really apply to a handfull of images. But I'll remain neutral, as I'm not directly opposed to it, either. 11:21, February 12, 2020 (EST)

Not sure what to think of this yet, but I think the purple should be a lighter color to make the text more readable. 14:46, February 13, 2020 (EST)


 * I can easily change the color to be more reader-friendly. I will hunt for a similar purple that's easier to read. Trig - 16:42, February 13, 2020 (EST)
 * Thanks! 20:07, February 13, 2020 (EST)
 * is #cb7eff or #debffb more appropriate?

 demonstration; original  demonstration; option 1  demonstration; option 2
 * I personally enjoy the original or lean towards the darker side of purple but it's up to the community. (I've never been great with color) Trig - 17:21, February 14, 2020 (EST)
 * I'd go with option 1. 15:05, February 19, 2020 (EST)

It seems that "original" does not necessarily equal "accurate" in all cases. Take File:Luigi - New Super Mario Bros U.png for example. Note that the optimized version contains a darker green and the gamma ("original") version contains a lighter green. Then look at File:NSMBU FourCharacters.png from the same game, where the opposite is true. Therefore, it seems that there are some images where gamma correction produces an accurate image, and other images where gamma correction produces an inaccurate image. Given this, I think we can't say that gamma should always or never be removed, since it depends on the image. How do we determine when the original is accurate, and when the optimized version is accurate? A side note: it is possible to keep certain metadata, such as the gamma chunk or embedded ICC profiles, while still optimizing the image, such as by passing the  option to   or the   option to. See this page for further explanation. I tested it on File:NSMBDS Goomba Artwork.png. Note: preserving only the iCCP chunk has worked for every image I've tested so far, but theoretically there may be older images that rely on the gAMA or cHRM chunks. Since these legacy chunks are very small, it's probably worth preserving them also. Maybe we could include this information in the policy, so that we can optimize the images without removing gamma.-- 00:01, February 16, 2020 (EST)

We could modify the template/proposed policy to consider this. Maybe something like:  This image contains gamma brightening, and should not be optimized without preserving iCCP metadata. -- 14:31, February 16, 2020 (EST)
 * The image-critical ancillary chunks are tRNS (used on Captain Toad: Treasure Tracker ripped textures by APNG Optimizer to greatly reduce file size), sBIT, pHYs, and the color space chunks, sRGB (when it specifies a different rendering intent than the default one), gAMA, cHRM and iCCP. So far only the tRNS, sRGB and gAMA/iCCP have been spotted, but I’m not sure if the others are featured as well, press release material might be the most at risk, if it was generated using the AdobeRGB color space.


 * In any case, this specific proposal deals with the gAMA chunk and possibly the iCCP chunk.—Mister Wu (talk) 18:55, February 16, 2020 (EST)
 * I'm not sure we should mention performing image optimization on the template at all given that it's now heavily discouraged at best by the image use policy. -- 19:24, February 16, 2020 (EST)
 * The Image Use Policy only discourages "Re-uploading existing images solely to optimize file size," not optimizing images you are planning to upload anyway. There could be other reasons (such as cropping) that one may modify an existing image, and many people such as myself optimize all pngs uploaded, including images to reupload. -- 19:30, February 16, 2020 (EST)
 * I would suggest writing a specific new page about Gamma Brightening, and having two sections to the page. One, very general in description, explaining what it is as simply as possible (metadata is a thing and while usually ok is not here and therefore needs to be kept, here's why we keep it), and the second half getting into the really technical stuff involved. While I like the detail that SMF67 and Wu are providing, I have absolutely no idea what just about any of that means. On the second point, I usually optimize uploads that are new nowadays, but I am duplicating them to compare them, just in case. Also, input on the color would be nice. Trig - 20:50, February 16, 2020 (EST)
 * I like color option 2 the most. -- 17:58, February 17, 2020 (EST)

@Trig Jegman, @Mister Wu, I made a quick (still incomplete) draft of a page that could describe the technical parts of color-correction metadata and how to safely optimize these images in my sandbox. There are still a few missing details I haven't figured out yet, and anyone is encouraged to add to it or take details from it to make something else (we don't have to use it of course, I don't know if all of the information is relevant/important to include). Additionally, while it might be nitpicky, I think it might be a good idea to refer to the metadata as "color-correction metadata" rather than "gamma brightening," since technically gamma is only one type of color-correction metadata and iCCP seems to be the most common from the images I've tested. -- 18:24, February 19, 2020 (EST)

Removals
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Changes
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Miscellaneous
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