Image Uploader that Sizes the Photo Like An Avatar

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

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Re: Image Uploader that Sizes the Photo Like An Avatar by hippo (Archbishop) on Jul 03, 2022 at 13:50 UTC
You have not said what image format(s) your system will support. So, for the general case I would start with Imager and go from there. If you are using CGI::Application then surely CGI::Application::Plugin::Thumbnail would be worth a look. It uses Image::Thumbnail under the bonnet. 🦛	[reply]
Re: Image Uploader that Sizes the Photo Like An Avatar by davies (Monsignor) on Jul 03, 2022 at 16:08 UTC
Could the code I wrote in [Solved] Tk not recognising GD image be what you want, with Discipulus's advice? Regards, John Davies	[reply]
Re: Image Uploader that Sizes the Photo Like An Avatar by kcott (Archbishop) on Jul 03, 2022 at 22:00 UTC
Take a look at Image::Magick. Its description starts with (my emphasis): "This Perl extension allows the reading, manipulation and writing of a large number of image file formats using the ImageMagick library. It was originally developed to be used by CGI scripts for Web pages." A link to extensive documentation follows. I believe that module only handles raster formats; but happy to be proven wrong (I did have a quick look for a list of available formats: couldn't find one). I routinely use Image::LibRSVG to convert SVG (a vector format) to raster formats; I've no idea if that would be useful for you. — Ken	[reply]
Re^2: Image Uploader that Sizes the Photo Like An Avatar by perlfan (Parson) on Jul 04, 2022 at 13:59 UTC
Yes, Image::Magick will do this easily. I recommend actually, storing the full size image and hiding the resized image behind a webserver call (that might look like the all to an image or a RESTful `GET` call in an `<img src...>` tag. Note, image scale attacks exist, but I only mention them because they are an interesting adversary parlay against the bort.	[reply] [d/l] [select]
Re: Image Uploader that Sizes the Photo Like An Avatar by LanX (Saint) on Jul 03, 2022 at 12:33 UTC
The crop part sounds rather like a JavaScript job ... Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery}	[reply]
Re^2: Image Uploader that Sizes the Photo Like An Avatar by harangzsolt33 (Deacon) on Jul 04, 2022 at 00:42 UTC
Yes, in fact, this entire task sounds like a JavaScript job. From JavaScript, someone can put a local image from a hard drive to appear on the web page. Then the user can crop it, resize it using JavaScript. See Croppic.js. Then inside a canvas object, the JavaScript can get the new resized image pixel by pixel and convert it into any kind of format and upload it to the other side where your Perl script handles it. The JavaScript side of it is done by the Croppic library, so most of the work is already done for you.	[reply]