basic image question

Questions and postings pertaining to the usage of ImageMagick regardless of the interface. This includes the command-line utilities, as well as the C and C++ APIs. Usage questions are like "How do I use ImageMagick to create drop shadows?".
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anthony
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Re: basic image question

Post by anthony » 2006-02-14T16:44:31-07:00

imguser wrote: hello,
whenever i got a image from webcam its having always width x height format with why width always>height???


Because that is what the web camera is generating. Even if the camera is rotated, the camare may note that it was rotates in EXIF meta data stored in the image, but the camera itself still sees the image in landscape (width>height) mode.
also how can i change image from 160x120 to 120x160 mogrify command never accepted my conversion why???


Rotate it.
mogrify -rotate -90 camera.jpg

WARNING: if your camera produces JPEG, do not you mogrify as JPG is a lossy format, and any load and save to this format reduces image quality (even at 100%). Always preserve the original unroated image if you have any chance you will need it again.

ASIDE: the 'jpegtrans' program that comes with the JPEG library can rotate a JPEG image without quality loss. For more JPEG details see
http://www.cit.gu.edu.au/~anthony/graph ... rmats/#jpg

You may also want to test if the image contains EXIF data, so you only rotate it if you need to.
and what i have to do to get image which have height> width??

Rotate it. See above.
Anthony Thyssen -- Webmaster for ImageMagick Example Pages
http://www.imagemagick.org/Usage/

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anthony
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Post by anthony » 2006-02-14T21:59:43-07:00

Prehaps you should look though the IM examples.

to produce a negative use -negate
to make a mirror -flop

More distorts can be seen in the "distort" second of the IM examples.

You may be especially interesting in "thumbnails"
Anthony Thyssen -- Webmaster for ImageMagick Example Pages
http://www.imagemagick.org/Usage/

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anthony
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Post by anthony » 2006-02-14T23:11:48-07:00

Nope sorry.
Anthony Thyssen -- Webmaster for ImageMagick Example Pages
http://www.imagemagick.org/Usage/

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