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Comments for JPEG compression: quality or quantity? #243

Open phinjensen opened 6 years ago

phinjensen commented 6 years ago

Comments for https://www.endpointdev.com/blog/2009/12/jpeg-compression-quality-or-quantity/ By Daniel Browning

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phinjensen commented 6 years ago 
original author: Jon Jensen
date: 2009-12-24T15:27:04-05:00

Very interesting, Daniel. I would not have suspected that ImageMagick and Photoshop have rough parity in file size/quality, and that's good to know.

What version of ImageMagick did you use in these tests? Have you found much difference in compression quality between different ImageMagick versions?

phinjensen commented 6 years ago 
original author: Daniel Browning
date: 2009-12-24T15:41:09-05:00

I used ImageMagick-6.5.1 for these tests, but when I compared with Photoshop it was an older version. I haven't checked different versions for compression quality, but I have for resizing. Ancient versions (e.g. 4.2) were much worse at resizing and resulted in bad aliasing artifacts.

phinjensen commented 6 years ago 
original author: Chris Olberding
date: 2012-08-20T10:53:12-04:00

The images on the post are broken, so I wasn't really able to see the results.

Wrote a script the helps automate running lossless compression algorithms. It's not directly applicable to the kinds of test you're running here but you might find it interesting or helpful.

http://blog.stationfour.com/automating-png-jpg-image-optimization-in-windows/