Export Texture2D wrong for game TokimekiMemorial1 switch

[YuriSizuku]

Code

import os
import UnityPy

print(UnityPy.__version__)
env = UnityPy.load("070ebd75fa14728b6efa688dcaf25b3ad6b53f60122957e823ae43d0d863df47.assetbundle")
for obj in env.objects:
    if obj.type.name == "Texture2D":
        data = obj.read()
        path = os.path.join("", f"{data.m_Name}.png")
        try:
            data.image.save(path)
            print(obj.container, obj.path_id, data.m_Name)
        except Exception as e:
            pass

Output:
1.22.3
assets/app/assetbundledatas/global/font/df-tokubutogothic-w10001.ttf 2743269464722013593 Font Texture
assets/app/assetbundledatas/global/font/psfont.png 3956642238002007481 PSFont

Error
The exported texture psfont is as below

To Reproduce
Here's the example asset bundle file.
070ebd75fa14728b6efa688dcaf25b3ad6b53f60122957e823ae43d0d863df47.assetbundle.gz

• following data:
  • Python version 3.8.15
  • UnityPy version 1.22.3

[isHarryh]

Using AssetStudio to open the image, got an "value out of range" error.

It might because the image has an unknown encoding or the image is corrupted.

PS: Your image's BuildTarget is Switch(38), TextureFormat is Alpha8(1). Your Unity version is (6000, 0, 29, 1). I guess this problem is caused by the Swizzle technique used by Switch and UnityPy cannot handle it well.

PS: The AssetStudio version I use is v0.16.47 .

[YuriSizuku]

Using AssetStudio to open the image, got an "value out of range" error.

It might because the image has an unknown encoding or the image is corrupted.

Using uabea (https://github.com/nesrak1/UABEA/releases/tag/v8) or assetstudiomod (https://github.com/aelurum/AssetStudio/releases/tag/v0.18.0) can export this kind of texture.

[isHarryh]

It is confirmed that AssetStudioMod v0.18.0 has implemented Swizzle texture decoding. Which is ported from https://github.com/nesrak1/AssetStudio/tree/switch-tex-deswizzle . But UnityPy has also already implemented Swizzle texture decoding, so I guess there are still some bug in UnityPy's implementation.

We will investigate this issue later. Thank you for your reporting.

[K0lb3]

@YuriSizuku thanks for reporting the issue with a sample...some people on discord could learn from that^^

I took a look at the issue just now, and figured out the cause.

The ported swizzling algorithm expected Alpha images as they are, so A or L mode for PIL images.
Due to the way I hacked it into the texture decoder, the algorithm gets an RGBA image with the arguments for an Alpha images though, which obviously doesn't work, as could be seen in the sample you've send.

It's rather easy to fix, which I will do tomorrow.

[isHarryh]

Okay. I have fixed this issue.

Since mode A has been deprecated in higher version of PIL, I use mode L to convert the Alpha8 texture.

Result:

I will create a PR together with some optimizations to the Texture2DConverter.

[YuriSizuku]

@isHarryh Thank you very much for fixing swizzle problem.
I also find another problem. Some of the Texture2D will fail. For example, o_title.opd.004.TITLE_10, -2253978278952133234 .

Here's the sample file.4c2fce8de58beec4c00eb4a0e7cb63798219ef40845fd9ce5caac9e679862428.assetbundle.gz .
THis assetbundle contains both swizzle and no swizzle textures.

import os
import UnityPy

print(UnityPy.__version__)
env = UnityPy.load("4c2fce8de58beec4c00eb4a0e7cb63798219ef40845fd9ce5caac9e679862428.assetbundle")
for obj in env.objects:
    if obj.type.name == "Texture2D":
        if obj.path_id == -2253978278952133234: # m_Name o_title.opd.004.TITLE_10
            print() # here the image is failed, with error "not enough image data"
        data = obj.read()
        path = os.path.join("texture2d", f"{data.m_Name}.png")
        try:
            data.image.save(path)
            # print(obj.container, obj.path_id, data.m_Name)
        except Exception as e:
            print(e, obj.container, obj.path_id, data.m_Name)

1.22.3
not enough image data assets/app/assetbundledatas/ui/title/top/anime/tex/f_ti_asa.png -8821489414920275171 f_ti_asa
not enough image data assets/app/assetbundledatas/ui/title/top/anime/tex/f_ti_ijy.png -7461452353158819954 f_ti_ijy
not enough image data assets/app/assetbundledatas/ui/title/top/anime/tex/f_ti_him.png -5370940219351303872 f_ti_him
not enough image data assets/app/assetbundledatas/ui/title/top/anime/tex/f_ti_kis.png -2508894997960172460 f_ti_kis
not enough image data assets/app/assetbundledatas/ui/title/top/o_title.opd.004.title_10.png -2253978278952133234 o_title.opd.004.TITLE_10
not enough image data assets/app/assetbundledatas/ui/title/top/anime/tex/f_ti_yos.png -1601477667513553414 f_ti_yos
not enough image data assets/app/assetbundledatas/ui/title/top/anime/tex/f_ti_nij.png -332955856442518853 f_ti_nij
not enough image data assets/app/assetbundledatas/ui/title/top/anime/tex/f_ti_kat.png 1705848395684871993 f_ti_kat
not enough image data assets/app/assetbundledatas/ui/title/top/anime/tex/f_ti_kiy.png 2610769001954651512 f_ti_kiy
not enough image data assets/app/assetbundledatas/ui/title/top/anime/tex/f_ti_mik.png 2744682033155613619 f_ti_mik
not enough image data assets/app/assetbundledatas/ui/title/top/anime/tex/f_ti_tat.png 3935480033426506342 f_ti_tat
not enough image data assets/app/assetbundledatas/ui/title/top/anime/tex/f_ti_kag.png 4254527588500095008 f_ti_kag
not enough image data assets/app/assetbundledatas/ui/title/top/anime/tex/f_ti_kos.png 8943327269797105746 f_ti_kos
not enough image data assets/app/assetbundledatas/ui/title/top/anime/tex/f_ti_sao.png 9126585017557340981 f_ti_sao

In AssetStudioMod it seems these texture2d are without swizzle.

It might be some problem for judging texture swizzle, for eample o_title.opd.004.TITLE_06.png.

[isHarryh]

These image do not use swizzle, but UnityPy use swizzle to solve them, so the width and height are incorrect while decoding, causing not enough image data.

This is a simple bug in the Texture2DConverter, to fix it:

-    if platform == BuildTarget.Switch and platform_blob is not None:
+    if platform == BuildTarget.Switch and platform_blob:

Reference:

https://github.com/nesrak1/AssetStudio/blob/e5c0d1909e090320eb88a2d163bb34c346a2947c/AssetStudioUtility/Texture2DConverter.cs#L37

Result after the fix:

I have updated my PR to contain this fix.

However, few images, like f_title1.png, are still corrupted.

[aelurum]

Because for Texture2D assets from unity 2020.2+ the m_PlatformBlob list is always != None.
So you also need to check the length of the list.
If a texture uses switch swizzling, the length of m_PlatformBlob will be > 0, if not, the list will be empty.

[isHarryh]

Because for Texture2D assets from unity 2020.2+ the m_PlatformBlob list is always != None. So you also need to check the length of the list. If a texture uses switch swizzling, the length of m_PlatformBlob will be > 0, if not, the list will be empty.

Yes, so if platform == BuildTarget.Switch and platform_blob can both check not-null and not-empty.

[isHarryh]

However, few images, like f_title1.png, are still corrupted.

Now, the remaining corrupted images (RGB24 swizzle format) have been repaired in PR.

Thank you for your samples @YuriSizuku .

[YuriSizuku]

However, few images, like f_title1.png, are still corrupted.

Now, the remaining corrupted images (RGB24 swizzle format) have been repaired in PR.

Thank you for your samples @YuriSizuku .

Thank you very much. I have also tested, this bug is fixed.