But in the case of comic files, the images are *already* compressed, via JPEG or PNG formats, so you really don't gain much anyways, since you can only compress information so much.īut for my money RAR is just not worth it in this context. The main advantage of RAR vs ZIP is that you can often get a better compression ratio, around 10% better. And on the Mac, there are some issues with the way Python is talking to the external 'unrar' programs (the 'subprocess' module) that makes it even slower, since it often has to retry reads. Under Windows it works fairly well, since it's talking directly to a DLL, but under Unix systems like Mac and Linux, it's using the 'unrar' program, and is a good bit slower to read a CBR vs a CBZ. ComicTagger app gets around this by talking to the 'rar' program direct from WinRAR, but it's really not an ideal solution.Īdd to this that Python doesn't natively support RAR decompression/reading either, and I am using a third-party python library called py-unrar2 () to support this.
That's why almost no comic apps will support the writing of CBR files.
The RAR/CBR format is a bit of a pain for developers since, while you can use the decompression for free, you need to pay if you want to include the compression in your app.