MSPaint: all transparency will be lost ...

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ChrisGreaves
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MSPaint: all transparency will be lost ...

Post by ChrisGreaves »

I have been seeing this caution for years, and see it every time I choose File, Edit on a PNG file (a screen snapshot is an example) and from MSPaint issue a saveAs to a JPEG format.
Typically I have saved a PNG image from the web, or taken a PrtScr snapshot myself.

I can't spot the difference when I view the original PNG and the final JPG files as desktop wallpaper or through Windows Image Viewer.

I am not worried, and I think I ought not to be worried. (If I can read the map of the Metro system, then I can read the map of the Metro system).

But why would anyone else care enough to want to be warned about losing transparency?

Thanks
Curious Chris
An expensive day out: Wallet and Grimace

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Leif
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Re: MSPaint: all transparency will be lost ...

Post by Leif »

ChrisGreaves wrote:
10 Jul 2020, 00:16
But why would anyone else care enough to want to be warned about losing transparency?
Because whereas .png files can support transparency, .jpg files can not, and MSPaint can't be bothered to check if there is any transparency, or if you have made any part of it transparent. You are simply being politely reminded that if your original picture included transparency, it will be gone. Forever.

Clear enough? :grin:
Leif

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HansV
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Re: MSPaint: all transparency will be lost ...

Post by HansV »

Some images have transparency - our smileys for example. The actual image in :smile: is square (15 x 15 pixels), but the colour around the yellow face is transparent: on a white blackground you'll see white, on a black background you'll see black etc.
For such images you won't want to lose that transparency - in the case of the smiley, you'd see a coloured square around the face on most backgrounds.
MS Paint doesn't support transparency, so if you edit an image in MS Paint, the "transparent" colour will be replaced with a fixed one.
For photos, this doesn't matter of course.
Best wishes,
Hans

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ChrisGreaves
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Re: MSPaint: all transparency will be lost ...

Post by ChrisGreaves »

HansV wrote:
10 Jul 2020, 06:31
...The actual image in :smile: is square (15 x 15 pixels), but the colour around the yellow face is transparent: on a white blackground you'll see white, on a black background you'll see black etc. ...
Leif and Hans: Thank you for your explanations.
***NOW*** I remember seeing this effect. Typically when I cut and paste an irregular portion of an image I see that White (non-transparent) background.

Would that back in the late eighties (or nineties or whenever; my memory is transparent) they knew about that one-time "Got it!" pop-up box. :grin:

Cheers
Chris
An expensive day out: Wallet and Grimace