Nickel Icons

[frostschutz]

This script extracts PNG/MNG icons from nickel (and possibly other binaries). It runs on disconnect from PC (currently without visual feedback). The extraction process takes about a minute.

You can edit and replace the PNGs with your own images, as long as they are not larger than the original image was. For some images it can be difficult to meet the size requirement: Reduce color depth. Try pngcrush/pngquant. Disable optional PNG data (comments, etc.). If nothing helps, reduce colors even further / remove details.

The custom images will be written directly back into the binary. The script does check for valid PNG header and filesize, but even so, bricking is still possible - make backups of your data.

To install, KoboRoot-NickelIcons.tgz » .kobo/KoboRoot.tgz

After installation you will find a .addons/nickelicons directory.

• .addons/nickelicons/uninstall.txt - uninstallation instructions
• .addons/nickelicons/report.txt - logfile of the last script run
• .addons/nickelicons/targets.txt - list of files to be processed by this mod (nickel)
• .addons/nickelicons/nickel/*.png - the extracted PNG images (leave as is)
• .addons/nickelicons/nickel/restore/*.png - put your edited PNG images in here (to be restored on disconnect)
• .addons/nickelicons/nickel/done/*.png - your edited PNG images (previously processed by the script - check report.txt for success)
• .addons/nickelicons/nickel/invalid/* - broken or invalid files found during processing

The script will not run if nickel/*.png exists (if it already extracted PNG before) and if nickel/restore/*.png does not exist (if there is no custom PNG to put back into the binary). So to start over you must remove .addons/nickelicons/nickel/*.png.

A reboot is necessary to make the changes visible.

In order to uninstall the Nickel Icons mod, simply delete or rename the .addons/nickelicons dir.

Uninstalling will not restore the original icons. You have to do so manually, before uninstalling, by moving the original PNG files into restore/. Alternatively, use a firmware update to get the original /usr/local/Kobo/nickel file back.

[Ken Maltby]

Perhaps, the animator images could be made modifiable with something like this?

Luck;
Ken

[frostschutz]

You mean the progress bar at startup? Those are different. Not PNG embedded in nickel but raw, gz-compressed files in /etc/images/*. This mod is more about icons (such as home / wifi / battery / menu) and other image data used by nickel.

You could use it on binaries, as long as they use PNG the same way... if you fancy a customized chess set or something... go nuts

[Ken Maltby]

Does anyone know a way to convert these .raw files into something usable? It seems like the screenshot process went through a raw to pam step, if I remember correctly.

Luck;
Ken

[frostschutz]

Kind of off topic, but ... :P

You can convert the raw files to png with an ffmpeg command that can be found in this forum somewhere. My pngcat program used to do PNG -> RAW conversions. You can find it somewhere in the history of my GitHub (google frostschutz github kobo pngcat). If you use pngshow (part of my ScreenSaver mod) something like this might work:

# rotate screen for pickel
cat /dev/zero | /usr/local/Kobo/pickel showpic
# whiteout
tr '\x00' '\xff' < /dev/zero > /dev/fb0
# actually display an image
/usr/local/ScreenSaver/pngshow something.png
# gzip raw framebuffer data into a file
gzip < /dev/fb0 > something.raw.gz

Haven't actually tested it. For the progress bar you need 11 images (/etc/image/product-on- 1 .. 11), more if you want to cover other products than just your own reader.

EDIT: Just tested it, works for me (H2O / dahlia)

[Ken Maltby]

123456

[frostschutz]

Updated it, apart from bugfixes it now also grabs MNG (animated PNG).
Nickel uses them for the rotating sync or loading icons...

[Alastair_S]

Originally Posted by Ken Maltby

Does anyone know a way to convert these .raw files into something usable? It seems like the screenshot process went through a raw to pam step, if I remember correctly.

Luck;
Ken

Ken,
what OS do you use? For MS Windows there is a great freeware program called IrfanView that can read the raw files (you need to supply the dimensions of the image, which will probably be the same as the screen size of the Kobo device you are using) and save them as something else.

[tshering]

Originally Posted by Ken Maltby

Does anyone know a way to convert these .raw files into something usable? It seems like the screenshot process went through a raw to pam step, if I remember correctly.

Luck;
Ken

See this post.

[surquizu]

I think it's not a very useful application, but it's very funny!.

The difficulty has been to find the images of my model of reader (there are many peers) and even more difficult to make an image smaller.

These are my new images. The files that I changed in my aura H2o with firmware v.3.16.0 are 4163626_5614.png and 4082981_10978.png

Thanks frostschutz

[frostschutz]

Originally Posted by surquizu

I think it's not a very useful application, but it's very funny!.

Glad you like it

[barobach_so]

hi
I have problem with this patch

when i transfer koboroot.tgz and disconect device after restart i found .nickelicon directory with three txt file

I made "nickel" folder in it and a "restore" folder in nickel folder, manually
I paste 2 PNG file in it ( didnt change name ) and after another restart there was no change in icons

patch made 2 other folders ( done and invalid ) and some png files with 0 KB size in nickel folder
what was my mistake ?
can u pls tell me the exact instruction ?

[frostschutz]

The extraction/patching process happens when you disconnect the device from USB connection (and you should give it some time to do so, like a minute or three). You have to reboot to make changes visible. Don't create folders manually, or the mod might think it already extracted/imported images and won't do anything.

It should say what it did or didn't do in the text files in the .nickelicons folder.

[barobach_so]

Originally Posted by frostschutz

The extraction/patching process happens when you disconnect the device from USB connection (and you should give it some time to do so, like a minute or three). You have to reboot to make changes visible. Don't create folders manually, or the mod might think it already extracted/imported images and won't do anything.

It should say what it did or didn't do in the text files in the .nickelicons folder.

hi
thank you

now it works fine

there are a lot of same pictures ( for example a kobo connected to a pc pic ) with different names

do you know which one should be replaced

my h2o on fw 3.15 has 967 pic and its difficult to check one by one

[frostschutz]

Sometimes you have the same picture but at differnet resolutions, so one of them is used by Kobo Glo, another by Kobo H2O, etc. The filenames might change with every firmware update too [they're byte offsets in the nickel file], so - it involves a bit of trial & error. There is no way to determine what's what automatically...