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How can I manipulate images (e.g. create thumbnails) AA version: 2.6 Article progress: Complete

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In Slice admin interface form for configuring fields there is an input box for parameters of insert function. For field with insert function "File = uploaded file", you can set these parameters:

        type of file : maximum image width : maximum image height : secondary image fields delimited with ## separator

Example:

if you insert parameters:
        image/*:450:600:image.....1##image......2
function will do these actions after submitting the item/article:

• check whether the file to be uploaded has proper type (image) and upload only such files (this works for any file upload fields, for example you can specify limit to application/msword or application/*)
• check if picture is bigger than maximum dimensions set in field parameters. If yes, image will be resampled to maximum dimension (aspect ratio maintained).
• if there are set any "other fields" (in this example "image.......1" and "image.......2"), function will also fill-in these fields with url to the same picture. If there are maximum dimensions set in parameters of these field(s), function will resize image accordingly.

Limits of the function:

• image functions work only if there is GD library installed (GD is standard part of PHP since PHP version 4.3.0)
• Image resampling functions work only with GD supported types (JPG, PNG, WBMP - not GIF - GIF will be supported since July 7th, 2004, when LZW patent expires world-wide)
• secondary image fields must be in the input form after source field
• filling of secondary image fields is not recursive (secondary image fields can not be defined in a chain)
• there is no error reporting

Last Edit: Aug 17 2011

<aafaq id=1662> ~ToDo: 1662 How can I manipulate images (e.g. create thumbnails) </aafaq> 

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