Creating a vignette overlay

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TuxForLife
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Joined: 2015-11-03T21:32:46-07:00
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Creating a vignette overlay

Post by TuxForLife » 2016-05-02T22:37:34-07:00

Instead of processing a vignette every time, I would like to create a vignette overlay and compose it over to decrease rendering time.

So I'm hoping to create a transparent canvas, with black corners, however, I can't seem to produce it correctly.

This one gives me a black canvas with black corners, so it's 100% black.

Code: Select all

convert -size 1920x1080 xc:none \
-background black -vignette 0x250+-60-60 \
vignette.png
This one gives me a black canvas with clear corners.

Code: Select all

convert -size 1920x1080 xc:black \
-background none -vignette 0x250+-60-60 \
vignette.png

snibgo
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Location: England, UK

Re: Creating a vignette overlay

Post by snibgo » 2016-05-02T22:56:17-07:00

When asking questions, please tell us your IM version and platform.

I don't know what effect you want, but your sigma is huge and your radii are negative. You really want circles with negative radii?! Try something like "0x25+60+60".
snibgo's IM pages: im.snibgo.com

TuxForLife
Posts: 3
Joined: 2015-11-03T21:32:46-07:00
Authentication code: 1151

Re: Creating a vignette overlay

Post by TuxForLife » 2016-05-02T23:05:50-07:00

Version: ImageMagick 6.9.0-4 Q16 x86_64 2016-04-13
Arch Linux

0x250+-60-60 was giving me what I wanted, subtle dark corners.

I want something like the first one, but just transparency instead of blue
http://imgur.com/a/beHbp

Thank you snibgo

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