Restricting uploaded photo sizes 1

[Glasgow]

I am developing a site which allows registered members to upload a personal (colour) photograph to the site for others to view in the same way as many forums do. For the moment I expect most photos to be about passport size in terms of on-screen display. Perhaps up to 150 x 150 pixels. I won't know the resolution.

In order to avoid unnecessary wasted disk space and to maintain reasonably quick load/display times, I need to set a sensible maximum limit on the file size of these images and I am happy with the logic required to control this. What I am uncertain about, however, is what kind of limit to impose.

Any suggestions?

 

[Qik3Coder]

I had this problem a little while back.

You could simply set a hard limit of 2x's what a decent JPEG would be (around 40k). You may want to validate the size of the image, to not have weird scaling issues later.

Here's what I did with a "avatar" image:

Notify the user what size you will save their image at.
Let the user upload just about any image.
Use the .Net framework to resize and convert it to a PNG.
PNGs have slightly better clarity than a jpg and will be a decent size.
This removes having to worry about code laced GIFs and overly huge BMPs.
This also allows for a transparency for those that select a GIF or PNG.

HTH,
Lodlaiden

If [blue]you have problems[/blue], I want [green]source code[/green] AND [green]error messages[/green], none of this [red]"there was an error crap"[/red]

 

[Glasgow]

Thanks for the reply. I had started to think in terms of a 50k limit so we are on the same wavelength there.

I've never resized an image before but it looks like this link:

http://www.4guysfromrolla.com/articles/012203-1.aspx#postadlink

will help.