JPEG progressive scans number

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mlabarinas
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Joined: 2015-08-11T20:27:41-07:00
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JPEG progressive scans number

Post by mlabarinas »

HI guys:

I want to know the number of scans with a progressive jpeg is generated, I use this command:

convert -interlace plane in.jpg out.jpg

Is it a default value? Can I change it? How?

Thanks.
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glennrp
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Joined: 2006-04-01T08:16:32-07:00
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Re: JPEG progressive scans number

Post by glennrp »

ImageMagick only offers progressive (-interlace plane) and nonprogressive (-interlace none). When writing a progressive JPEG, the number of scans is the default value for the jpeg library. This seems to be 8, but others are possible when using libjpeg's "cjpeg", but not when using ImageMagick (see wizards.txt in the libjpeg distribution).
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