[Solved] Odd outcome when saving image to JPEG.

[KaoDome]

I've just come across something odd, I'm linking to the problematic picture for you to try (it's ~2.2MB zipped): https://gofile.io/d/tflvWZ

 

It's a 24-bit 933x1080 PNG file I wanted to compress to JPEG resulting in a file smaller than 512 bits, however when saving as JPEG even with the slider all the way to the left with several artifacts the file still weighs over 1.5MB. I'm using 4:4:4 chroma subsampling but it happens with the other options too.

 

Is there something wrong with the picture? The PNG file was produced by paint.net, I have checked 4.2.11 in case there was something wrong in the .12 release, but it seems to also produce the same results. In case it's relevant, I'm running Windows 10 2004.

Edited June 19, 2020 by KaoDome
Prefix title with [Solved].

[null54]

29 minutes ago, KaoDome said:

Is there something wrong with the picture?

That PNG file contains a large amount of XMP metadata and an ICC color profile, Paint.NET is preserving this metadata when you save as JPEG.

After removing the XMP metadata and the ICC color profile with Metadata++ the JPEG file size dropped to ~31 Kb.

 

[KaoDome]

1 hour ago, null54 said:

That PNG file contains a large amount of XMP metadata and an ICC color profile, Paint.NET is preserving this metadata when you save as JPEG.

After removing the XMP metadata and the ICC color profile with Metadata++ the JPEG file size dropped to ~31 Kb.

 

 

Ohhhhh! So that's what it was!

 

Thanks, I had no idea of what was going on, but I knew it had to be something related to that picture; it's the first time I've come across it.