saharnooby / qoi-java Goto Github PK

Whether I use QOIUtil.readFile vs BitmapFactory.decodeFile of Android, or I use QOIUtil.readImage vs BitmapFactory.decodeStream , it seems that Android's implementation is faster to parse PNG files over QOI:

From inputStream of the resource (files are within the app) :
QOI took 84 ms
PNG took 25 ms

From a file outside the app:
QOI took 36 ms
PNG took 30 ms

And that's before getting Bitmap instance out of the QOIImage instance, which I don't understand how to do.

Tested on Pixel 4 with Android API 32 on the "wikipedia_008" image files, from here (got from here) :
https://qoiformat.org/qoi_test_images.zip

See attached project:

My Application.zip

How could it be?
Is there anything that can be improved in the implementation?
And how do you convert the output of the function to a working Bitmap instance?

Hey,

I have noticed that there is a bug in the encoder. Specifically https://github.com/saharNooby/qoi-java/blob/main/src/main/java/me/saharnooby/qoi/QOIEncoder.java#L174 here. The original C implementation is using signed arithmetic in this place https://github.com/phoboslab/qoi/blob/master/qoi.h#L465

This may not seem like a big issue since the encoding and decoding seems to be working fine but if you take a .qoi file, decode and then encode it back with this library then the resulting file will not always be identical to the original .qoi file.

You can verify this by performing a test like this:

1. Download test files https://qoiformat.org/qoi_test_images.zip
2. For each test file run a test:
   • decode the file
   • encode back the decoded file
   • compare the resulting file with the original test file byte by byte