Legacy ImageMagick Discussions Archive

I've ended up with the fact that IM is not able to handle Group4-Compressed Bilevel files of that size. Or, to be more gently, it makes no sense to do it with IM. I finally found a suiteable tool called thumbnail (bundled for Debian in "libtiff-tools") which uses the libtiff , a specialized library ...

I understand and find the idea stunning simple. My problem is, that processing the compressed bilevel files takes sooo much time. But even processing uncompressed bilevel TIFFs takes too long. This is a IM problem, because on bit gets converted to 3 or more bytes per pixel by reading in the image ...

Hello and thank you very much! This code would do, but what i forgott to mention is that those bilevel TIFFs i'm talking about are very large (16200*23700 pixels). It would take several Minutes so process one image... Any hints about that? Can i convert the TG4s into something else before (with an ...

Hello,

i have several TIFFG4 compressed bilevel images and want to calculate the converage of black pixels from a given rectangle of that page. So is it possible to count the black/white pixels of an arbitrary rectangle inside an image?

I see. The image i rotate is resized to about 30%. Does the order of scale/rotate matter? In my case i see no optical difference.

Hello,

when i rotate an image using the "-rotate 7" command, the resulting image looks unsharp and somewhat "flat" (less colors). Do i do something wrong? Re-sharpening it with "-sharpen 1" corrects this a bit.

Thanks a lot. Inbetween i found an example using "-flatten". Is this just another way to do it?

Hello, i'm new to IM and now that i can mount two or more images together on a new, resulting image, which is pretty cool for me :-). But for now i use the -size operator to set the resulting image's size (as read from the examples). Is it possible to place two or three images onto a "background ...

I'm one step further. After compiling a current version from source, it works! On my 3.4ghz Xeon it takes about 4 minutes (like stated before) to create the preview. Even the preview contains a big black area (something is wrong), it is faaar to slow. So, what can i do to find the source of this ...

If your version of IM is still at 6.3.7 per your earlier message, then perhaps you really need to upgrade. You are over 200 versions behind. Well i guess you're right. But there is no more recent version available, so i think i had to compile it from source... if no one knows a repository holding a ...

Wow 4mins. is way to long for what i need to do with this.
So what options do i may have to reduce this time dramatically?
Is the compression or the internal data structure (tiled,strips, or whatever) critical?

magick wrote:Which version of IM are you using? It seems to work ok with ImageMagick 6.6.0-8. Can you try that version? If not, add -debug cache to your command line post the output.

Did this already. Please look at the beginning of the thread.

I did, but did not tell you. The path in the above terminal-output points to a disk which has about 40gig free, which should be enough. Why does it not convert on my Linux box? I tried it on another host, the same result. Give the Linux host about 5GIG of RAM, nothing changes. Please, all who can ...

Sounds good, but doing your command only shows convert: unable to extend cache `large.tif': Invalid argument. convert: missing an image filename `preview_image.tif'. Giving it -debug cache it shows 2010-03-24T13:16:16+01:00 0:01 0.010u 6.3.7 Cache convert[2500]: cache.c/unknown/2162/Cache destroy ...

Tried to convert with tiffcp into an uncompressed version, still the same. It runs on Debian Linux machine having 512MB of physical RAM. IM version is 6.3.7 08/07/09 Q16 (from Lenny packages). I used -debug and see it will try to create a 3.64gb tempfile, which is quite large, but even the disk ...