h1. Installing and using ImageMagick

Jun 23, 2015

*On my local Linux Mint (Ubuntu)

@apt-get install imagemagick perlmagick@

If package not found, then first do:
@apt-get update@
and then try the install again.



h2. EXIF Data

http://stackoverflow.com/questions/1708417/how-can-i-extract-exif-data-using-perlmagick

http://hacktux.com/read/remove/exif


may want:
@apt-get install libimage-exiftool-perl@

@exiftool coreopsis.jpg@ will provide some info about the image.

but this might be better:
@apt-get install jhead@

@jhead coreopsis.jpg@


if want to remove exif data from an image:

q.
After ImageMagick is installed, you will have /usr/bin/mogrify available. The mogrify command can be used to strip Exif data from images.

mogrify -strip imagename.jpg

If you need to process a large number of files, use find and xargs:

find ./folder_of_images -name '*.jpg' | xargs mogrify -strip
q..




hr.

Perl usage
http://www.imagemagick.org/source/examples.pl


hr.


did not need to execute these commands. 

@apt-get install libconfig-yaml-perl@

@perl -MCPAN -e 'install Image::Magick'


hr.

install CPAN
reload CPAN


hr. 

check Ubuntu version

@lsb_release -a@


h2. orientation

fence.Value 0th Row 0th Column
1 top | left side
2 top | right side
3 bottom | right side
4 bottom | left side
5 left side | top
6 right side | top
7 right side | bottom
8 left side | bottom
fence..


h2. Links

http://www.imagemagick.org/script/formats.php

http://www.imagemagick.org/script/perl-magick.php

http://www.imagemagick.org/script/examples.php

http://www.imagemagick.org/source/examples.pl

http://www.graphicsmagick.org/perl.html

http://sylvana.net/jpegcrop/exif_orientation.html



h2. Using Client-side Javascript to Resize an Image

http://stackoverflow.com/questions/5343915/javascript-library-similar-to-imagemagick-i-e-resize-images-and-pictures-whil

http://stackoverflow.com/questions/2303690/resizing-an-image-in-an-html5-canvas

http://davidwalsh.name/resize-image-canvas


hr.

http://stackoverflow.com/questions/6150289/how-to-convert-image-into-base64-string-using-javascript

http://jsfiddle.net/handtrix/YvQ5y/


hr.

https://developer.mozilla.org/en-US/docs/Web/API/HTMLCanvasElement/toDataURL


hr.

http://www.sitepoint.com/html5-ajax-file-upload/

http://stackoverflow.com/questions/9395911/sending-a-file-as-multipart-through-xmlhttprequest

http://www.sitepoint.com/html5-javascript-file-upload-progress-bar/


hr.

https://dojotoolkit.org/documentation/tutorials/1.10/ajax/

https://dojotoolkit.org/documentation/tutorials/1.10/mobile/flickrview/part3/index.html

https://dojotoolkit.org/documentation/tutorials/1.10/jsonp/


http://dojotoolkit.org/reference-guide/1.10/dojo/json.html


hr.


http://stackoverflow.com/questions/21944247/sending-off-an-image-name-with-ajax


hr.

http://stackoverflow.com/questions/14383557/setting-canvas-todataurl-jpg-quality


q.
Edit: If you're using Fabric.js, another, very simple and human-readable way, is this:

canvas.toDataURL({
   format: 'jpeg',
   quality: 0.8
});
This also allows you to have other options, giving you the ability to crop the image, etc:

canvas.toDataURL({
    format: 'png',
    left: 300,
    top: 250,
    width: 200,
    height: 150
})
q..



hr.



http://code.flickr.net/2012/06/01/parsing-exif-client-side-using-javascript-2/



hr.


http://drbacchus.com/rotating-an-image-with-imagemagick-and-perl/

use Transpose or Transverse. for my usage, it will mainly be Transpose for photos taken in portrait mode on the phone which creates images with orientation = 6.