Image Converter/Compressor for Embedded Devices

+ Description

8bbw2c.sh

converts B/W image to 8-bit C/C++ array. Please note, the image should be Black & White, neither Grayscale nor in Color.

16brgb2c.sh

converts 16-bit color binary image into RGB565 C/C++ array.

img2bin.sh

converts images to binary or C/C++ RAW pixel array (RGB565 and RGB888). Tested only for .jpg and .png images for now.

Saving PNGs in Adobe Illustrator:

File - Export As:

1. File format - PNG
2. Non-interlaced
3. Optimization - preferable "None"

Bin header format:

#	Name	Length in bytes
1	Compression (boolean)	2
2	Width	2
3	Height	2
4	Flag of alpha channel	2
5	Dominant (background) color	(2 * Bytes Per Pixel)
6	Color as Alpha channel	(2 * Bytes Per Pixel)

INFO:
The above scripts are using in, out and .tmp directories in order to seek for a source and store the final result accordingly.

mix8bbw2c.sh

converts a few similar images into the dependant scructure of binary arrays. The script tries to find an image that has the most similarities with all the others and creates *_base_bmp array. Then converts all the other images to binary, excluding the *_base_bmp block. In principle the logic is diplayed on the image below.

In order to decode and display the binaries on the device you can use the following functions:

• drawBmpRGB - displays RGB565 bitmap graphic
• drawBmpRGBA - drawing an image that has alpha channel or use an alpha color
• drawBmpBW - drawing single 8-bit B/W compressed bitmap
• drawBmpBWChunk - drawing 8-bit B/W chunked compressed bitmap

The following is an example of encoded (using mix8bbw2c.sh script) B/W chunked bitmaps:

/**
 * fmt: 8-bit B/W chunked compressed image map
 * img: lcrtc7
 * bmp: lcrtc7_bmp (non-inverted)
 * gen: mix8bbw2c.sh (v.1.3) at 27.07.2020 20:07:25
*/
const uint8_t off_base_bmp[] PROGMEM = {
0xFF,0x02,0x00,0x0C,0xFF,0x03....
};

const chunk8b_t off_chunk PROGMEM = {
    off_base_bmp,
    0,
    16, 16, 0
};

const uint8_t alert_chunk_bmp[] PROGMEM = {
0x00,0x37,0x00,0x02,0x00,0x02...
};

const chunk8b_t alert_chunk PROGMEM = {
    off_base_bmp,
    alert_chunk_bmp,
    16, 16, 30
};

const uint8_t working_chunk_bmp[] PROGMEM = {
0x00,0x31,0x00,0x01,0xFF,0x01...
};

const chunk8b_t working_chunk PROGMEM = {
    off_base_bmp,
    working_chunk_bmp,
    16, 16, 108
};

	Please refer to issues 🪲 if you have any suggestion or found an error.