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Optimal PNG compression level?

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Optimal PNG compression level?

Postby dg-505 » Thu Mar 19, 2020 12:10 pm

Hello @all texture artists :)

I'm creating some hires textures for aircraft instruments wit GIMP.
When exporting them to PNG, what compression level shall I choose?
Regarding file size: Highest compression level results in 310 KB, lowest compression level results in 16 MB file size.

Which compression level is the best compromise for FG?

Here are links to the files:
High compression, 310 KB
Low compression, 16 MB

Thanks for your advice
Jonathan
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DHC-6 Twin Otter development
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Re: Optimal PNG compression level?

Postby Richard » Thu Mar 19, 2020 3:12 pm

For PNG files generally the highest compression (lowest file size) is best; and also this is the best for development repositories and downloads.

Generally do not save images with an alpha channel active - because it can cause strange rendering behaviour due to the way that transparency is handled inside the rendering.

Inside the simulator there is very little difference in load times for compressed vs. uncompressed it is the overall resolution that makes more difference.

So it is more important to size the image appropriately based on the normal in sim viewing size - the example you provided should be 256x256

There is also a valid argument for distributing your model with jpg textures; in the example I'd expect around 150kb for a jpg image.
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