This tutorial will teach you how to convert a PNG image to RLE format and make it usable for kernel logos. Android system uses its own graphical image formats. Most of the Android devices use PNG files but there are also a few others that use RLE image as kernel logo so you will need to convert PNG to RLE.
The RLE format has a pretty good compression ratio and it’s very fast compared to other formats. To make a PNG image as a kernel logo firstly you have to convert it to RLE format.Unfortunately converting
Unfortunately converting an image from PNG to RLE requires a lot of tools and much work.
You can find many ways online but almost all require ImageMagick to work correctly. There are few others that don’t need this app to work but they aren’t easy to work.
To make things easier and help you to quickly convert PNG to RLE, an XDA Senior Member named as alireza7991 created a simple tool to make things much easier.
The tool is very simple to use and can do the work in just a few seconds. The tool is called PNG2RLE and with few clicks will convert a PNG file to RLE and make it compatible for kernel logo for almost every Android system.
What is PNG2RLE?
PNG2RLE is a cross-platform tool which converts PNG files to RLE.This format is used by some devices as a kernel
This format is used by some devices as a kernel logo format because has a good compression and is very fast. There are some similar scripts but they are neither cross-platform nor standalone app so they will need ImageMagick to work.
PNG2RLE doesn’t require anything special to work and it can be used in Windows computers, Linux and even in Android device. The project is an open source and you can find it here.
How to use PNG2RLE
Usage of this tool is pretty simple and straightforward. You just have to execute the binary and put a path to the input and output files. Then you will get a RLE file ready being placed in your device ramdisk. Read carefully “Read Me” text file. It can be found among other files you can download them from here.
RLE compression: Format uses a simple compression method, it uses 2 cells for each pixel, one stores pixel infor and the second stores number of repeats of pixel. For example if you have 1000 pixels in a line, it will be a pixel with 1000 repeats.
RLE pixel format: Unlike PNG files, RLE uses 16-bit pixels. This means that there is 5 bits for red, 6 for green and 5 for blue. No alpha is implemented. This makes RLE pixel 50% smaller than RBGA pixels in PNG.
How PNG is converted to RLE
Both formats use completely different compression and pixel format. At first we have to convert PNG to raw rgba8888 pixels, then it should be converted to rgb888 and finally, a hybrid converter will convert it to RLE565.
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