The GUIslice image2c is a standalone desktop application that is designed to generate memory based images for GUIslice API.
Input images can be in BMP, PNG, JPG, or GIF formats.
The generated output code (.c) will contain the imported image as a C Array that can be included in your projects. These files may be used directly by the GUIsliceBuilder for inclusion into your projects. You can refer to GUIslice/examples/arduino/ex28_ard_btn_img_flash for a sample application using C arrays for image buttons.
GUIslice API and therefore this utility only supports two output formats for C Arrays. The most common is 16 bit color per pixel and the other is Monochrome 1 bit per pixel.
The typical TFT screens we hobbist use only support 16 bit pixels, RGB565 format, which requires the alpha channel (transparency) to be removed along with a corresponding reduction in the number of supported colors compared to 24 or 32 bit colors per pixel.
The RGB888 format (24 bit color) allocates 8 bits to red, green and blue colors; While RGB565 allocates only 5 bits for red, 6 bits for green, and 5 bits for blue. Moreover, RGB888 would require storing and transmitting 3 bytes per pixel consuming more RAM memory and which would need more time to transmit. RGB565 format is more efficient in this regard since it only requires two bytes per pixel.
- Build instructions can be found in
BUILD.txtfile.
The needed version of Java is now custom built and distributed with GUIslice_Image2C so you no longer need to deal with its installation.
Download the image2c-win-x64-2.02.zip from github GUIslice_Image2C Releases: https://github.com/Pconti31/GUIslice_Image2C/releases
Then unzip and run the resulting executable image2c-win-2.02
This can create a desktop icon you can click on to run. Optionally, you can use GUIslice_Image2C\image2c.bat file to run.
Download the image2c-{opsys}-{arch}.{release}.{build}.tar.gz using operating system and cpu architecture (ie., linux-x64) from github GUIslice_Image2C Releases: https://github.com/Pconti31/GUIslice_Image2C/releases
untar into your home directory.
Example: Open a terminal
cd $HOME
tar xvzf image2c-linux-x64-2.02.tgz
Then enter the new GUIslice_Image2C folder
cd GUIslice_Image2C
To run:
./image2c.sh
The current GUIslice API has not be updated to handle 1 bit monochrome images without crashing.
You can use my respository for the patches. https://github.com/Pconti31/GUIslice/tree/pconti-DRAWMONO-FIX
The outstanding pull request is: ImpulseAdventure/GUIslice#456
You must mark in the image's property view if an image is transparent otherwise GUIslice API will output a white background.
Transparent? = true
If you are using a 1 bit image C file you must set the format property in its property view correctly or a crash will occur.
Image Format = GSLC_IMGREF_FMT_RAW1
The default is 24 bit color which will crash your application.
Transparent images are only supported by PNG files and BMP with 32 bit color. The typical TFT screens we hobbist use only support 16 bit pixels which requires the Alpha channel (transparency) to be removed along with a reduction in the possible number of supported colors.
Transparent pixels will be converted automatically to GUIslice API's transparent indicator of the Pink (Magenta) color. If your image only contains 1 color with a transparent backgound the C array will automatically be exported in 1 bit format.
If you have configured GUIslice API to use another color instead of Magenta you may select the colored Pink box on the lower right of the display and choose another color to match the one you actually configured. Changing this color requires you to modify your GUIslice/config/*.h file's variable GSLC_BMP_TRANS_RGB
It should be noted that while BMP's that use 1 bit pixels do support two colors, one for background and one for foreground. GUIslice only support the foreground color. The background is treated as transparent. GUIslice_Image2C will allow you to change the foreground color and output the new color to your C array. It will also allow you to overwrite the current foreground color with a new one. Simply press the New Foreground Color button and a popup color chooser menu will appear.
For Monochrome images only the utility needs to know the color of your foreground to accurately generate your C array. However, it turns out that there is no way to determine programmatically which color is foreground and which is background. This program will first determine the number of colors used in your image.
If only one is found (most likely a PNG image with one color and a transparent background) that color will be marked as your Foreground color. Nothing more for you to do.
If two colors are found it will grab the first one it finds and make it the foreground and present it to you in the Foreground color box. If our utility guessed incorrectly or you want an inverse image then simply click the foreground color button and it will be exchanged with the second color found.
Now only for Monochrome images the default background color output for your C array will be white. This will be shown in the Monochrome Output button. You may override this color by pressing this button and a color chooser will appear. This is only needed when or if you are going to override the current color.
You should also realize that 8 bit MCU like Arduino UNO and Mega can only address within a 16-bit range so arrays larger then 65kb will not load. There likely will be size limitations with other MCUs.
GUIslice API pull 456 - C Array had Width and Height reversed. A problem for rectangular Icons.
Upgraded to FlatLaf 3.3 and Java 18 amd added better support for MacOS.
MAC OSX 13.2 - Fatal error when accessing JComboBox
Added execute permissions to Java for Linux and MacOS.
Packaged custom built Java with Image2C and added a Windows installer.
- Issue 5 v2.00 c-array not correct on one- & two color pictures
The number of available Themes has be greatly increased for this version. Checkout options->themes for a list.
Previously Monochrome images (binary Bitmap images that only used 1 bit per pixel) were converted to 16 bit color. They still displayed properly but took up 16 times the RAM. Now they are correctly output to C arrays as unsigned char with a dramatic reduction in RAM.
The default Monochrome image is assumed to have a white foreground and a black background.
Version 1.0 of GUIslice_Image2C would show Trandsparent pixels as black causing some images to appear as a filled in black rectangle. This is fixed in version 2.0
The Non-Built in Java Themes are supported by the FlatLaf project.
The FlatLaf project is on GitHub: https://github.com/JFormDesigner/FlatLaf
Some Imaging is provided by the Pumpernickel project. https://mickleness.github.io/pumpernickel/