j123b567 / lv_utils

Convert images or system fonts to C arrays. Written for LittlevGL embedded GUI library

These PHP scrips are the online converter tools:

• Image converter: https://littlevgl.com/image-to-c-array
• Font converter: https://littlevgl.com/ttf-font-to-c-array

Here you you can see how they work or download them to run offline.

Get started

This guide shows how to use the converters offline in a command line on Linux

1. Install PHP: sudo apt-get install php7.0-cli
2. Intall the Image manipulator extension for PHP: sudo apt-get install php7.0-gd
3. Clone or download the lv_utils repository: git clone https://github.com/littlevgl/lv_utils.git
4. Go to the lv_utils directory.

Run the Font converter offline

5. Copy a TTF file you want to use into the lv_utils directory
6. Run the script: php font_conv_core.php "name=arial_20&font=arial.ttf&height=20&bpp=4&uni_first=32&uni_last=126"
7. Chek the craeted C file in lv_utils directory.

The required arguments of the script:

• name name of the output file and font
• font name of font file to use (must be a *.ttf file)
• height desired height in px
• bpp Bit-per-pixel (1, 2, 4 or 8)
• uni_first the first unicode character to convert
• uni_last the ast unicode character to convert

Optional arguments:

• built_in convert a built in font with all bpp (0 or 1)
• list list of characters to include (must be in rango of uni_first and uni_last and in ascendant order). E.g. "list=123abc"

Example with all options Convert only the numbers and + - sign with Arial font (The plus sign is replaced with %2B): php font_conv_core.php "name=arial_num_20&font=arial.ttf&height=20&bpp=8&uni_first=32&uni_last=126&list=%2B-0123456789&built_in=1"

Run the Image converter offline

5. Copy a BMP, JPG or PNG file you want to use into the lv_utils directory
6. Run the script: php img_conv_core.php "name=wallpaper&img=red_flower.png"
7. Chek the created C file in lv_utils directory.

The required arguments of the script:

• name name of the output file and image
• img an image file

Optional arguments:

• transp transparency handlig. Possible values are: none, alpha (add alpha byte to every pixel) or chroma (mark the image as chroma keyed). Default is none.
• format C array or Binary output. Possible values are: c_array, bin_rgb332, bin_rgb565, bin_rgb888. Default is: c_array.

Example with all options Convert a bunny.png with alpha for all pixels to C array: php img_conv_core.php "name=icon&img=bunny.png&format=c_array&transp=alpha"