Grainy Background Fix

Fix the grainy space backgrounds present in Katamari Damacy Reroll with a simple mod.

Introduction

As many people have noticed, the space backgrounds in this game are super grainy. Many have said that this is a result of a bad port, but the reality is that the grainy backgrounds are very much on purpose. The original PS2 version of the game ALSO has grainy space backgrounds, but the issue is that, due to digital to analog signal conversion, the grain is lost when displayed on the television screen. This is also due to blurring and to CRT screens being darker/having less contrast. If you don't believe me, you can see the space grain very clearly when there are transparent objects (such as text bubbles) present (See this video), but regardless of whether they're intentional or not, many people (including myself) do not like them. Luckily for us, Katamari Damacy Reroll runs on Unity, which has many tools available to extract and modify game assets!

I don't care if it's intentional, how do I fix it?

To browse Unity assets, use this tool: https://github.com/Perfare/AssetStudio
To modify Unity assets, use this tool: https://github.com/DerPopo/UABE

Go to the Katamari Damacy Reroll game files (right click the game in your Steam Library, click Properties.., Click Local Files, Click Browse local files. Open the folder called katamari_Data. In there should be all the asset files.

The backgrounds in question that need to be fixed are located in the following files:
sharedassets1.assets
sharedassets3.assets

The textures that need to be modified are called:
back (located inside sharedassets1.assets)
back_result (located inside sharedassets3.assets)

To extract the space backgrounds, open the asset files with AssetStudio (first link) by clicking File->Open file, then click the Asset List tab. Browse the massive list of files for the relevant Texture2D. Right click it, and press export selected assets.



Now, take your paint program of choice and edit the background to your liking! In my case, I chose to use a JPEG Artifact removal tool, I applied a Gaussian blur, and then lowered the contrast on the image.

Once you've modified the background(s) to your liking, save your image and close Asset Studio if it's still open. Now, open Unity Asset Bundle Extractor (second link), and import in the asset that you're modifying (such as sharedassets1.assets). When you import it, a new window should pop up. Find the relevant Texture2D that you're modifying (such as back) and select it. Then, on the right panel, click Plugins, Edit, Load, and feed it your background png edit.

Afterwards, press the OK button, then go to File->Save, and save your asset file. Then take it to the katamari_Data folder and replace the relevant asset file. Do this for the backgrounds on both asset files (sharedassets1.assets and sharedassets3.assets).



Now, this won't fix the video cutscenes (such as the intro movie where the king destroys all the stars), just the ingame ones, because those are actually videos. The video cutscenes are inside the katamari_Data/StreamingAssets/Movies folder, and are in usm format. While there are plenty of tools to decode this format into avi, and then reencode it back into usm, my experiments haven't yielded very good results, as the decoded videos usually came with glitches and artifacts...

I don't computer, can you just give me a download link?!

Sure thing. First, download the mod from here.
https://drive.google.com/file/d/1jyngTN3wD-Nr6yQGx0_W4CM6VRNNKr4Y/

Afterwards, go to the Katamari Damacy Reroll game files (right click the game in your Steam Library, click Properties.., Click Local Files, Click Browse local files. Place the files inside the zip provided from the download link inside the Katamari_Data folder, CLICKING YES TO OVERWRITE THE FILES.

Be aware that this DOES NOT FIX CUTSCENES because of the reasons explained in the section before. This merely fixes gameplay related backgrounds (The level selection, The King talking to The Prince, etc...).

I don't like your edit. I want my space background to be PITCH BLACK!

Well, I've given you the tools and know-how on how to do that. Do it yourself :)

Happy rolling!

[☠SOON☠]

I like the grain, but I like the option you've given. Thanks!

[Buu342]

@Paul Read the comments below yours.

[Paul]

I think you forgot to fix the constellations screen background.

[Future Ukyo]

Based

[Gecko]

@Buu342
It's working for me now!
I downloaded your new zip file, and I got a beautifully dark sky now, with a couple of twinkling stars in it, like in your screenshots. Thank you!
Still haven't been successful with the constellation screen either, though.

[Buu342]

@Gecko That's really weird, because I just redownloaded my game, threw in the two files inside the zip, and it worked without problems. I shouldn't need to upload the resS files, but I've gone ahead and added them in as well.
I tried modifying those two but doesn't seem like they're the ones for the constellation background.

[Gecko]

@Buu342
Would you mind adding the corresponding ".assets.resS" files to your drive, maybe? It appears just using the .assets ones doesn't work, since your textures show up as blank even when I inspect them using AssetStudio. So that would be my guess.
Regarding the constellations screen, there are "back_mono" and "back_spot" textures that show up in several of these asset files. Perhaps it has to do with those?

[Buu342]

@Gecko Just booted up my game and it's looking how it always has for me. All I can really suggest is following the second chapter of this guide and making the edit yourself, like that you can tweak the background to your liking.
I never went to the constellations screen so I completely missed it :p
From the looks of it, it probably also uses a space texture stored somewhere in the Unity assets, so it's a matter of finding and modifying it.

[Gecko]

Does this still work? I used the files from your drive, and my space is pitch black now. Better than before, but still.
Also, do you think it would be possible to do one for the "View Constellations" screen, as well?

[Sinful Sorcerer]

Thanks, that looks a lot better!