Blurry images on mobile

[Nydestroyer]

So I use mangadex mostly from my phone and I have noticed a problem where random chapters of a thing will not load properly and very blurry on mobile but work just fine on the desktop. This also occurs when I go to the groups website and view the image. I have a galaxy s8... I feel like this isnt actually a mangadex issue but instead something to do with the phone itself or maybe just mobile browsers? I dont really get it.

I have tried many mobile browsers and nothing changes, switching to desktop mode also does not fix it. I have seen other people talking about this problem in comments on the chapters themselves so I know I am not alone.

Does anyone know a solution or even a possible hint at one?

 

[blackyawgdom]

Or it could just be a crappy quality image to begin with...

 

[Plykiya]

@Nydestroyer above

there is no downscaling going on on our end, images are displayed as is

if the "random" chapter is shit quality (pretty common), it'll look like shit

some groups will upscale their chapters when their raws are tiny which leads to art that looks extremely blurry

 

[Nydestroyer]

@Plykiya
Please read the content of my post again, I confirmed the images worked on a desktop but where only blurry on mobile. I tested the images on a 4k monitor(this was not in the original post but I think it might be relevant) and it was extremely clear and very large.

I also said it was the same case on the groups website, on mobile the chapter has a had quality, but on the desktop they are just fine. Thus i said it was most likely not mangadexes problem but instead some other problem with some shared viewer code or maybe something else and was wondering if anyone knew what the problem actually was or had any additional information in it.

I will get some screenshots and photos to upload here after I get off work in approximately 8 or 9 hours.

Another note is it's not the whole chapter, it starts off clear for a few panels and then will randomly degrade into a messy unreadable blur fest.

 

[Nydestroyer]

Okay here is the problem in full. These four images explain the weirdness perfectly. This is for the webcomic Elqueeness.
Manga dex mobile

Manga dex website

Translators group site on their reader http://ghajik.ml/
mobile

Desktop

@Plykiya does it make sense why I am putting in the forum post now? This is a very very odd situation

edit: fixed images, also second edit, even though the two mobile pictures look similar if you look closely they have different timestamps and an up arrow found on the translators reader and not mangdadex, I have no clue how I ended up taking almost an identical positional screenshot of the chapter on the new phone tab lol

 

[Nydestroyer]

@AbyssalMonkey I am on a very high speed wifi connection on the same internet as the pc and I have tried it on three different browsers and all of them have the same problem. Another thing that made me dismiss it being something like what you suggested is the comments of that very chapter. There are only two and both complain about unreadable image quality. It's an issue that is real and only present when viewing these images on mobile. But it was a good theory on maybe why it was happening. Although I wont discount the possibility that me and the two commenters both have Galaxy S8s and maybe it's a samsung issue.

Chapter comments in question.
https://mangadex.org/chapter/745945/comments

Edit: tested it on the browsers after clearing cache and being on my 4g data and it still occurs so the part about ISP is also unlikely.

 

[MavB_Ver]

Have you tried viewing the images without using MD reader? Just to make sure the issue is about something between the reader and your device itself.

Edit: I mean viewing the images directly, using the image address.

 

[Teasday]

If I were to make a guess, the issue is that the entire chapter is one a few huge 1,440px × 37,332px images which some mobile browsers may well have problems displaying correctly, if they manage to at all.

So if I'm right, the solution is to ask the group to split up the image into smaller chunks. Or to use a better browser.

 

[Nydestroyer]

@Teasday that does seem like a likely reason (although I have tried chrome and samsung browsers on the chapters with the same result) but yea based on the image size being a commonality on other chapters I have noticed this problem with that's a good bet.

Is there any reason why manga dex dosn't limit image lengths? I am assuming its something to do with ease of use for uploaders and less image requests for display but idk. Seems like allowing such massive page lengths counters the reader options for single page vs double page vs on giant strip and makes them a inconsistent feature.

 

[blackyawgdom]

Or you could do what people did for 20 years and actually goto the groups website or irc channel if you wanted to download their releases....

 

[Nixie]

this seems to be a browser issue from what I can tell (I have the same problem)
my workaround so far has been downloading the image itself and opening it with an image viewer app on the phone which gives a perfectly clear image.
opening the image downloaded through the browser however still gives the blurry version
edit: I would have tried messing with the css settings for images to see if it's possible to force full resolution but I'm not sure how to do this on a phone/tablet

 

[Hassico]

So I did some research, here is what I found.
Phones, android or ios, have different GPU capabilities, specifically the ability to tile images. The GPU divides the image into smaller parts to process it before displaying it on screen, this is all to reduce memory usage and efficiency.

What is happening:
The software you are using, in this case chrome Android or IOS or some other apps, their image rendering engine is not programmed to handle image tiling thus, in case the GPU encounters a long image in height it deals with it as a whole big chunk and renders it in low quality to avoid memory bursts and crashes. A major player is the prowess of the GPU, for example some phones' GPU can handle image heights up to 40,000 pixels without tiling because it is powerful, and other phones cannot handle processing such a big image without tiling and delivers a blurry image. Usually phones' GPU can handle up to 4,000 pixels as an average.