Dithered Edges when converting from PNG to GIF - RESOLVED

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mrshake
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Re: Dithered Edges when converting from PNG to GIF

Post by mrshake »

It appears the white blend worked fine.... I might have to adjust a bit of fuzz to get it all happy... now to figure out how to enable that transparent chanel.
mrshake
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Re: Dithered Edges when converting from PNG to GIF

Post by mrshake »

I've tried setting alpha to on or transparent.. its still not re-enabling the transparency... am I doing it wrong somehow?
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Re: Dithered Edges when converting from PNG to GIF

Post by mrshake »

I'm still having problems getting transparency working.
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fmw42
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Re: Dithered Edges when converting from PNG to GIF

Post by fmw42 »

These all seems to work for me with transparent backgrounds in IM 6.4.7-10 Q16

convert rose: -matte -background none -rotate 20 rose_r20.png
convert rose: -alpha on -background none -rotate 20 rose_r20b.png
convert rose: -alpha activate -background none -rotate 20 rose_r20c.png
convert rose: -channel rgba -background none -rotate 20 rose_r20d.png
convert rose: -background none -rotate 20 rose_r20e.png


are you saving as PNG?

are you setting the background to none?
mrshake
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Re: Dithered Edges when converting from PNG to GIF

Post by mrshake »

fmw... I'm limited to gif for the final output. to try and get the best edges on the rotated image... I'm floodfilling the white to the edges, but its ending up black.
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fmw42
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Re: Dithered Edges when converting from PNG to GIF

Post by fmw42 »

mrshake wrote:fmw... I'm limited to gif for the final output. to try and get the best edges on the rotated image... I'm floodfilling the white to the edges, but its ending up black.
The commands above work also for .gif output format, but as gif is binary transparency, off or on and png is variable transparency, the gif results are more jagged when magnified to see how the edge looks.

You can try using some other background color (say gray50) and then using -fuzz and -floodfill to change it to transparent.


convert rose: -background gray50 -rotate 20 \
-bordercolor gray50 -border 2 \
-channel rgba -alpha on \
-fill none -fuzz 10% -floodfill +0+0 gray50 \
rose_flood.gif
mrshake
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Re: Dithered Edges when converting from PNG to GIF

Post by mrshake »

Is it ok to bump this?
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fmw42
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Re: Dithered Edges when converting from PNG to GIF

Post by fmw42 »

mrshake wrote:Is it ok to bump this?

Bump? Do you mean escalate to someone else? If so, certainly. Hopefully Anthony or Magick will answer. But you ought to provide an example and explain exactly what you don't think is working.
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Re: Dithered Edges when converting from PNG to GIF

Post by mrshake »

fmw42,
I hope this doesn't come across as rude, but if you go back to page 1 of this thread... there are LOADS of examples and explanations. Thanks for your help though, I do appreciate it!
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fmw42
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Re: Dithered Edges when converting from PNG to GIF

Post by fmw42 »

mrshake wrote:fmw42,
I hope this doesn't come across as rude, but if you go back to page 1 of this thread... there are LOADS of examples and explanations. Thanks for your help though, I do appreciate it!

No problem. Sorry I did not go back to page 1. My mistake. Hopefully you can get your problem resolved.
mrshake
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Re: Dithered Edges when converting from PNG to GIF

Post by mrshake »

No problem!! Thanks again for your help!
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