Tools to process DWIN LCD display .ICO files.
DWIN LCD displays use a number of image and container files to skin the UI elements on the display. These displays are used on Creality's Ender 3 v2 and other 3d printers, and the configuration files to support these displays is included in the Marlin firmware.
One file they use is "9.ICO", which is a structured file containing the icons. This project contains two tools to help developers manipulate these ICO files.
dwin-ico-tools consists of two tools: splitIco and makeIco.
"splitIco.py" reads an ICO file, and extracts the component icon images, saving each into a new directory. Each icon is named by its index in the ICO, and is named using symbol names from the Marlin dwin.h header file for this display.
"makeIco.py" is the inverse: it reads the images from a directory, and combines them to create a valid .ICO file.
The dwin-ico-tools are written in Python 3, and use the Pillow image library.
This is a new project and I don't forsee having a strict versioning in the tools.
That said, the tools correspond the the DWIN image and header files included in Marlin 2.0.7, as of 1-oct-2020.
These tools were created by:
- Brent Burton [@b-pub]
dwin-ico-tools is published under the GPL 3 license. See the LICENSE file for details.
The dwin-ico-tools are simple command-line programs that you run from a terminal. The files here do not need installation, but there is one dependency that must be in place before they work.
The following dependencies can be installed with pip:
- python3 -m pip install pillow
The dwin-ico-tools process the 9.ICO firmware file. The easiest way to do this is to create a directory to isolate the changes, and make a copy of 9.ICO there:
$ mkdir hackicons
$ cp 9.ICO hackicons
$ cd hackicons
We'll use this setup for the following explanations.
To edit the individual icons, the archive must be split first.
Do this with splitIco.py:
$ python3 splitIco.py 9.ICO icons
The "icons" parameter is the name of a directory to create (if missing) and store the individual JPEG icon files. While running, this program will output each file it writes with related information such as resolution, output file name, and some perhaps uninteresting info about the offset and size of the original 9.ICO content. It looks something like:
Splitting 9.ICO into dir icons
Splitting Entry Data...
00: offset: 0x001000 len: 0x10a2 width: 130 height: 17
Wrote 4258 bytes to icons/000-ICON_LOGO.jpg
01: offset: 0x0020a2 len: 0x0eac width: 110 height: 100
Wrote 3756 bytes to icons/001-ICON_Print_0.jpg
02: offset: 0x002f4e len: 0x0eaa width: 110 height: 100
Wrote 3754 bytes to icons/002-ICON_Print_1.jpg
...
91: offset: 0x0345fc len: 0x0d89 width: 110 height: 100
Wrote 3465 bytes to icons/091-ICON_Info_1.jpg
Once you have the individual JPEG files saved, you can edit them using whatever tools or programs you want. See section 'Caveats' below.
After editing, the 9.ICO archive must be regenerated. This is done
by makeIco.py:
$ python3 makeIco.py icons test.ICO
Making .ico file 'test.ICO' from contents of 'icons'
Scanning icon directory icons
...Scanned 91 icon files
Scanning done. 91 icons included.
$ ls -l *.ICO
-rw-r--r-- 1 bpub staff 217989 Apr 15 17:35 9.ICO
-rw-r--r-- 1 bpub staff 217989 Apr 15 18:15 test.ICO
$
The generated output, test.ICO, is the same size in this example and should not be a problem.
Since details of the DWIN internal firmware are not known (by me, at the time of writing these scripts) the limits of file sizes are unknown. In addition to 9.ICO, the firmware uses files 0_start.jpg, 1_English.jpg, and 2_Chinese.jpg, which provide a startup image, and raster messages in two languages for labeling fields. It is unknown what file size limits there are for either these files, or the individual JPEGs in 9.ICO, or the total size of 9.ICO itself.
For example, I changed 0_start.jpg to a colorful background image, resulting in a JPEG of 50KB (original was 28KB or 30KB). The display would not operate properly when my 0_start.jpg file was in place. Restoring the original file worked and the display was normal. So this hints the limit is between 30 and 50KB (maybe 32KB?) for that file.
Fortunately, it seems that problems caused by bad image files are easily correctable by restoring the original images. However, there may be some situation where the display unit is bricked by incompatible files. Keep that in mind when hacking your devices' firmware, it's always a risk.
The reward for reading this far is a script to programmatically swap the blue and red channels of JPEG files. This is the script I used to create yellow icons from the original cyan icons. Cyan (#00ffff) goes to yellow (#ffff00) by swapping these channels.
$ python3 swapBlueAndRed.py icons/*.jpg
processed 000-ICON_LOGO.jpg
processed 001-ICON_Print_0.jpg
processed 002-ICON_Print_1.jpg
...
processed 090-ICON_Info_0.jpg
processed 091-ICON_Info_1.jpg
And then run makeIco.py to rebuild the ICO archive.