Search found 11 matches

by Nemo_bis
2016-02-02T04:12:47-07:00
Forum: Users
Topic: Tuning options to convert images to JP2
Replies: 7
Views: 12150

Re: Tuning options to convert images to JP2

I am not 100% sure, but I think the -defines at http://www.imagemagick.org/script/command-line-options.php#define only work with OpenJPEG and not Jasper. Might be. We have upgraded to latest ImageMagick and "-quality 85" or similar work well. The only "issue" is that Photoshop users (as well as Lur...
by Nemo_bis
2016-02-02T04:09:05-07:00
Forum: Users
Topic: Resize image to specified size (kb)
Replies: 7
Views: 15880

Re: Resize image to specified size (kb)

The size limitation is currently only for JPEG as the define name implies. But if on Linux, Mac OSX or Windows with Cygwin, you can do that with my script, downsize, at the link below. It does not care about image format. I had some issues with this helpful suggestion. Moved to http://www.imagemagi...
by Nemo_bis
2016-02-02T04:08:41-07:00
Forum: Fred's Scripts
Topic: Problems with Fred's downsize script
Replies: 1
Views: 14585

Problems with Fred's downsize script

I'm trying to use http://www.fmwconcepts.com/imagemagick/downsize/index.php to reduce some JPEG-2000 images to a specified target size, per http://www.imagemagick.org/discourse-server/viewtopic.php?p=127981#p127981 Thank you for providing this useful utility! It would be useful to know some examples...
by Nemo_bis
2015-10-06T11:51:29-07:00
Forum: Users
Topic: Tuning options to convert images to JP2
Replies: 7
Views: 12150

Re: Tuning options to convert images to JP2

Yes I know JP2 is relatively new, and it's great that IM supports it at all! The landscape for JP2/JPEG 2000 in FLOSS isn't favourable at all. Don't use an "=". -quality 60 Ahem, right. Sorry. This works in 6.7.7-10. I got confused because neither command works on fedora 21/22, while the current Ubu...
by Nemo_bis
2015-10-06T08:52:29-07:00
Forum: Users
Topic: Tuning options to convert images to JP2
Replies: 7
Views: 12150

Re: Tuning options to convert images to JP2

I'm stuck on 6.7.7-10 because of reasons, is there any setting I can use? http://www.imagemagick.org/script/jp2.php seems to talk of recent versions only: $ convert 00001.tif -define jp2:quality=60 00001.60.jp2 warning: ignoring invalid option quality $ convert 00001.tif -quality=60 00001.60.jp2 con...
by Nemo_bis
2015-10-06T06:45:10-07:00
Forum: Users
Topic: jpeg 2000 compression
Replies: 2
Views: 8095

Re: jpeg 2000 compression

See http://www.imagemagick.org/script/jp2.php ; jp2 is lossless only if used with

Code: Select all

-quality 0
, which has some marginal space saving over a LZW/Zip TIFF.

Otherwise, you can get unexpected results: viewtopic.php?p=125169#p125169
by Nemo_bis
2015-10-05T07:49:31-07:00
Forum: Users
Topic: convert is toooooo slow with many images
Replies: 6
Views: 7566

Re: convert is toooooo slow with many images

Another experience: to create a PDF from 24 JPG files, convert eats 3 GiB RAM and 4 GiB swap, bringing the machine to swapdeath, and is eventually killed by Linux. This makes sense given http://www.imagemagick.org/discourse-server/viewtopic.php?f=1&t=28438&p=126258 says we need 8 bytes per pixel and...
by Nemo_bis
2012-10-25T13:38:14-07:00
Forum: Digital Image Processing
Topic: Convert JPEG from progressive to baseline losslessly
Replies: 14
Views: 46827

Re: Convert JPEG from progressive to baseline losslessly

It "works" as in it produces a non-interlaced image from an interlaced one (and three times faster than convert), but I'm not able to say if this has been lossless. I can assume it was? Yes, it has been lossless. The -perfect isn't necessary in this case, but it doesn't hurt. Also, if you want to k...
by Nemo_bis
2012-10-25T08:35:50-07:00
Forum: Digital Image Processing
Topic: Convert JPEG from progressive to baseline losslessly
Replies: 14
Views: 46827

Re: Convert JPEG from progressive to baseline losslessly

Use jpegtran. I remember that it can do so in a lossless way. Thank you, I didn't see anything in the docs but looks like a null transform works, like jpegtran in.jpg > out.jpg or, to be safe: jpegtran -perfect in.jpg > out.jpg It "works" as in it produces a non-interlaced image from an interlaced ...
by Nemo_bis
2012-10-24T17:28:34-07:00
Forum: Digital Image Processing
Topic: Convert JPEG from progressive to baseline losslessly
Replies: 14
Views: 46827

Convert JPEG from progressive to baseline losslessly

I hope this is the correct section, forgive me if it's not. I need to convert some progressive/interlaced JPEGs to baseline format. A simple "convert" or "convert -interlace none" does it, but I've been told «I'm fairly certain that convert is performing a conversion from the DCT domain into the rea...
by Nemo_bis
2012-06-16T02:37:29-07:00
Forum: Users
Topic: mogrify converts CR2 to JPG but doesn't copy images from tmp
Replies: 0
Views: 3350

mogrify converts CR2 to JPG but doesn't copy images from tmp

I have successfully used convert IMG_6081.CR2 IMG_6081.JPG; then I tried mogrify -format jpg *CR2 in the folder, with about 700 images for a total of 16 GB; after a long busy while, the task finished with no errors but no JPG had been produced: I checked /tmp and they all were still there instead of...