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[Elixer]

I've amassed a huge volume of screenshots in BMP format. I've long intended to convert them into PNG. Before I go ahead I want to ask:

1) Is PNG the best choice? (I'm only interested in lossless compression)

Maybe. What resolution are we talking about?

2) What's the best batch converter for converting BMP to PNG? IrfanView (my favorite image viewer) does it, but it's pretty slow. Anything that's properly multithreaded or CUDA accelerated?

Irfanview does batch conversion, as does imagemagick.

3) Any specific settings I should use when compressing to PNG? I've seen some debate around the best compression level, something like the highest level not always resulting in the smallest file. I also wonder about playback; will high compression levels affect the smoothness of playback on weak (non PC) devices? I hate any latency when browsing.

What do you mean playback? These are static images, so, any computer these days can show them adequately.
You can experiment with compression levels, just batch convert them, at different levels, and compare.
You can also use pngout if you want to optimize for size.

 

[Lorne]

+1 Irfanview.

 

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