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[IM 6.6.2] identify.exe ignores -size option
Posted: 2010-07-21T07:56:11-07:00
by paulborile
Hi,
we switched from IM 6.5.4 to 6.6.2 (and went back to 6.5.4) because it seems that identify 6.6.2
ignores the -size 64x64 option we use to lower the execution time of identify -verbose command.
We use this tecnique as indicated in a previous post (
viewtopic.php?f=3&t=16070)
to limit the image area taken into account by the identify command.
This, on a specific test file, gives 0.2 secs identify 6.5.4 execution time compared to 2.2 secs with identify 6.6.2
(the same time we have on identify 6.5.4 WITHOUT the -size 64x64 option).
Chance to have this fixed in some next version ?
Re: [IM 6.6.2] identify.exe ignores -size option
Posted: 2010-07-21T08:56:10-07:00
by snibgo
Does "-ping" do what you want faster?
identify -verbose -ping x.x
Re: [IM 6.6.2] identify.exe ignores -size option
Posted: 2010-07-21T08:57:27-07:00
by fmw42
At some recent release -size was changed to -define jpeg:size=
see
http://www.imagemagick.org/Usage/formats/#jpg_read
The changelog shows
2009-11-26 6.5.8-1 Chris Madison <madisonblu@gmail...>
Add -define jpeg:extent option to restrict the maximum JPEG image file size.
Re: [IM 6.6.2] identify.exe ignores -size option
Posted: 2010-07-21T12:41:59-07:00
by Drarakel
You probably meant that line:
2009-09-15 6.5.6-2 Cristy <quetzlzacatenango@image...>
# Use -define jpeg:size to scale a JPEG image to the specified size.
@paulborile:
It's all in your older thread. Just use "-define jpeg:size=64x64" instead of "-size 64x64" (of course, it's only for JPGs).
Re: [IM 6.6.2] identify.exe ignores -size option
Posted: 2010-07-21T19:10:28-07:00
by anthony
fmw42 wrote:At some recent release -size was changed to -define jpeg:size=
see
http://www.imagemagick.org/Usage/formats/#jpg_read
The changelog shows
2009-11-26 6.5.8-1 Chris Madison <madisonblu@gmail...>
Add -define jpeg:extent option to restrict the maximum JPEG image file size.
Actually
-size was not changed at all. Just its use for JPEG image reading was separated as it caused problem and confusion with its normal usage as a
-size setting for image creation.
So
-size used to set size for new images being created by internal image creation methods xc: plasma: gradient: etc...
While
-define jpeg:size is used to hint to the JPEG library the final size of the image (get something this size or slightly larger). That causes the library to skip unneeded columns and rows of pixels. Of course you should still specify at least double the final 'resize' of the image so as to avoid excessive aliasing effects of column and row removal.
See JPEG readin Options
http://www.imagemagick.org/Usage/formats/#jpg_read