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1. Misty (misty@digipres.club)'s status on Saturday, 26-Oct-2024 05:59:35 JST Misty

   Graphics question: I've got a set of transparent graphics in old BMPs which uses a colour as the alpha mask. Not all of the magenta pixels are exactly the same tone - seems like there's some gradient. Is that a technique that was ever used for 8-bit transparency back in the day? Or is this just a sign that the edge cutout wasn't done precisely?

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Saturday, 26-Oct-2024 05:59:34 JST Foone🏳️‍⚧️

     in reply to

     @misty I think that's just a mistake, yeah. There are some very rare cases where paletted files have more than one level of transparency, but that usually depends on specific shades of grey and their palette index, not magenta. You use magenta when you need only one transparent color

   • Misty (misty@digipres.club)'s status on Saturday, 26-Oct-2024 06:01:37 JST Misty

     in reply to

     And I guess followup question: if this *was* used for 8-bit transparency, is there a good way to do an automated conversion to a real alpha channel?

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Saturday, 26-Oct-2024 06:01:37 JST Foone🏳️‍⚧️

     in reply to

     @misty I have some code to do this that works by calculating all the possible shades of grey and alpha values and how they'd merge together, and figure out what combination is closest to what we get. It's a mess and can't really run outside my machine, but I'd be happy to run it on your files if you can send 'em

   • Misty (misty@digipres.club)'s status on Saturday, 26-Oct-2024 06:06:28 JST Misty

     in reply to

     • Foone🏳️‍⚧️

     @foone That makes sense, thanks! I was figuring it was likely a mistake.

     This is in some files from something that was never finished, so it tracks that it just hadn’t been polished up yet.

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Saturday, 26-Oct-2024 06:09:57 JST Foone🏳️‍⚧️

     in reply to

     @misty ahh, yeah, that makes sense. Probably they just did some rotation and we're planning to come back and clean it up

   • Misty (misty@digipres.club)'s status on Saturday, 26-Oct-2024 06:49:42 JST Misty

     in reply to

     • Foone🏳️‍⚧️

     @foone That would be a big help, thank you! How can I send the files?

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Saturday, 26-Oct-2024 06:52:44 JST Foone🏳️‍⚧️

     in reply to

     @misty dm me a link to a one click hoster, or dm me for my email address?