Some png files when resized with png.quality results as empty/transparent png file about imageflow HOT 5 CLOSED

So, I created an integration test on the latest version - but it works on my machine. Can you verify this is the correct input file? Maybe GitHub reencoded it?
https://imageflow-resources.s3.us-west-2.amazonaws.com/test_inputs/png_turns_empty.png

Using w=1230&h=760&png.quality=75&mode=crop&scale=both, I get https://imageflow-resources.s3.us-west-2.amazonaws.com/visual_test_checksums/0E5E63543D35A149D.png

from imageflow.

Hmm, this is failing on windows but not linux.

from imageflow.

And yet even on windows the result looks correct, despite being compressed differently. Can the problem image be emailed to [email protected] to make sure GitHub isn't 'repairing' it? Also, can you try with the very latest Imageflow release? This was listed as being in an older version.

from imageflow.

So, GitHub apparently re-compresses images. The image you e-mailed me is a 24-bit PNG, 18.4KB, and the image GitHub lets me access is a 32-bit PNG, 27.5KB

from imageflow.

This was specific to PNG files with a zero alpha channel, encoded when using lossy PNG, and when no transparency-inducing operations are performed. Thank you for e-mailing the problematic file, that allowed me to diagnose the issue.

from imageflow.