help Need help with Cartagra's Remake image files

[Sigma57f]

Yesterday I downloaded Cartagra «Rebirth FHD Size Edition» (Innocent Grey / Gungnir), mostly because of the remastered character sprites and backgrounds, but I've come across a wall at the moment of extracting them. Unlike previous games, this one has the images in a .cz file format, and so I can't view them or convert them to PNG. I've noticed that GarBro is able to view some of these .cz files, so I did some digging and it seems it's because of this:

 The files with CZ1 work fine.

 The ones I'm interested in have this and GarBro can't view them.

If I manually change it to CZ0, CZ1 or CZ3, it does "work" and GarBro can view them, but the image ends up being really, really distorted.

I'm not sure if this is some kind of compression or encryption thing, but this is where I'm at right now, so any help would be highly appreciated. I'm not sure where to go from here, I just want to be able to convert them to PNG, at least.

If there are any tools or scripts that may be able to help, please let me know!

Edited June 7, 2023 by Sigma57f

[REtransInternational]

On 6/7/2023 at 7:39 AM, Sigma57f said:

If I manually change it to CZ0, CZ1 or CZ3, it does "work" and GarBro can view them, but the image ends up being really, really distorted.
 

What does the distortion look like? A picture is worth at least 1k words.

[Sigma57f]

10 hours ago, REtransInternational said:

What does the distortion look like? A picture is worth at least 1k words.

CZ0:


CZ1:

CZ3:

 

The images are definitely made with libpng from what I could find. I've also tracked down some of the locations where this CZ encoding appears. Here's one of them.

I might as well attach some of the game files if anyone wants to check them out.
.cz Image, Game's executable, Game's executable .bak

[REtransInternational]

Thank you for the additional information and sample. Does this look correct for an extraction of your sample image?

If it is correct, please provide a few more samples, preferably of different dimensions, for validation.

[BerniceRyan]

I don't have any idea about it.

[Sigma57f]

17 hours ago, REtransInternational said:

Thank you for the additional information and sample. Does this look correct for an extraction of your sample image?

If it is correct, please provide a few more samples, preferably of different dimensions, for validation.

It is, yes!! Tysm! I may be asking too much here, but would it be possible to make them transparent, without the black background? That'd be great.

In any case, here are the other samples. There are background images, character sprites and some system images too:
Samples.zip (You may need to add ".cz" at the end of the filenames manually)

Edited June 23, 2023 by Sigma57f

[REtransInternational]

Thank you for the samples, they validate the decoding is successful. Yes, this format has separate alpha channel.

Please find analysis report and sample code here: https://www.mediafire.com/?4sjk7crcsbaklc8

[Sigma57f]

Can confirm it works like a charm! I was able to convert the decoded files to PNG with a simple Python script.
I highly appreciate all the help. Thank you very very much!! 

[HataVNI]

What the fuck. these images were some real nightmare fuel. But I'm glad that things are fixed. Another happy customer! 
（●＾o＾●）

Fellow Tengu enjoyer, too!

[corruptingheart]

On 6/26/2023 at 2:51 AM, Sigma57f said:

Can confirm it works like a charm! I was able to convert the decoded files to PNG with a simple Python script.
I highly appreciate all the help. Thank you very very much!! 

Hi, I know I’m replying half a year later but I’m currently attempting the same thing you did (extracting the sprites from FHD) and I was wondering if you could share your Python script you used to convert the decoded file to PNG? I’ve tried searching online for a script and writing my own to no avail. 

Thank you in advance for your time ^^

[Sigma57f]

On 12/6/2023 at 5:12 AM, corruptingheart said:

Hi, I know I’m replying half a year later but I’m currently attempting the same thing you did (extracting the sprites from FHD) and I was wondering if you could share your Python script you used to convert the decoded file to PNG? I’ve tried searching online for a script and writing my own to no avail. 

Thank you in advance for your time ^^

Sorry for the late reply, here you go! Took me a bit to find it:
Cartagra Rebirth - PNG Conversor Script

I've included a batch file to speed up the process. Just needs to be in the same folder as cz4dec.exe. The Python script only needs Pillow to be installed

[Poucks]

Hi there. I don't know A THING about extracting files from games. I've tried using garbro but that didn't work on my gamefiles, maybe I just downloaded corrupted files.

I need your help please. Did anyone managed to extract the CGs from that game? If you, can you please send an archive link?  

[Sigma57f]

Since I've been asked twice for CGs, I went ahead and made a guide for converting the assets. This should suffice, hopefully. The file where the CGs are located at is called EVENTCG.PAK.
Video guide for converting CZ assets to PNGs
The "decoded" and "PNGs" folders must be created as the guide shows. Can be modified by editing the batch file anyway

[Poucks]

Sadly, I can't open the files in GarBro, like you did. My gamefiles must be corrupted.... Thank you for the video, man.