image optimizer for web

Pingo (a14) JPEG File Rotation Isn't Always Lossless

Alex said, on 06/03/2022
Sample Files: https://github.com/recurser/exif-orientation-examples
ECT Command: ect.exe -9 -strip -progressive -autorotate -keep --mt-file "Landscape_2.jpg"
Pingo Command: pingo.exe -s9 -notime "Landscape_2.jpg"

I was testing some JPEG files with exif orientation metadata in them with both Pingo and another program called Efficient Compression Tool (ECT). There are two settings in ECT for JPEG autorotation.

1. ) -autorotate Automatically rotate JPEGs, when perfectly transformable.
2. ) -autorotate=force Automatically rotate JPEGs, dropping non-transformable edge blocks.

While testing, ECT gave me the error "Landscape_2.jpg can't be transformed perfectly" when using its -autorotate setting on this file. Pingo on the other hand autorotated the file, dropping non-transformable edge blocks, even while using the -sN setting which should be lossless.

Can you please include functionality in Pingo to only autorotate JPEG files when perfectly transformable?
cédric (dev) said, on 16/05/2022
maybe as a flag later
Alex said, on 17/05/2022
Thanks for your consideration Cédric. A flag in Pingo with this functionality would be extremely valuable to me.

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