JPEG 2000 DPI / Density

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lokelo

JPEG 2000 DPI / Density

Post by lokelo » 2008-04-05T19:04:09-07:00

I'm using the MagickNet API to try to convert 300 DPI images from TIF to JP2 files but the files are always reported as 72 dpi when querying the FILE with the density tag?
Is the JP2 filetype able to store DPI info?

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fmw42
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Re: JPEG 2000 DPI / Density

Post by fmw42 » 2008-04-06T14:27:03-07:00

what is your command line?

did you include -density?

see
http://www.imagemagick.org/script/comma ... p?#density

see the note about density for jpg and jpeg2000 at
http://www.imagemagick.org/Usage/formats/#jpg

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magick
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Re: JPEG 2000 DPI / Density

Post by magick » 2008-04-14T12:11:36-07:00

ImageMagick currently does not save the resolution for JP2 images. If you know of a way to note the resolution with the Jasper delegate library, let us know and we will add a patch to Imagemagick.

krisbfunk

Re: JPEG 2000 DPI / Density

Post by krisbfunk » 2008-10-21T10:07:51-07:00

Is this still the case? Is this something that other conversion utilities (like Kakadu) also have a problem with? As, I was unable to get the resolution information retained in jp2 files using a kakadu conversion either ... I would normally attribute it to missing a command input.. but since reading your posts I wonder if it's something bigger.

So institutes using Imagemagick to convert to lossless jpeg2000 as an archival format are actually losing the dpi information when storing their files in their repositories or to off site storage.. interesting. I suspect that if this data is not at least recorded in the metadata stage, this could produce some problems down the road.

krisbfunk

Re: JPEG 2000 DPI / Density

Post by krisbfunk » 2008-11-03T09:40:59-07:00

anyone?

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magick
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Re: JPEG 2000 DPI / Density

Post by magick » 2008-11-03T11:12:59-07:00

ImageMagick currently does not save the resolution for JP2 images. If you know of a way to note the resolution with the Jasper delegate library, let us know and we will add a patch to Imagemagick.

thor
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Re: JPEG 2000 DPI / Density

Post by thor » 2012-03-02T12:49:20-07:00

Is this still the case? I really would like to put a density marker in my jp2 conversions. My images will at some point be OCR'd and made into PDF and I would like the PDF's to be viewing the original size and not based off of 72 dpi.

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