Shrink images when detected as above a certain resolution/file size

[tomrow]

Currently, some otherwise simple pages struggle to load on devices with very small memory or slow network adaptor due to the size of images on the page. Currently, WebOne has the capability to call ImageMagick to re-encode JPEG format images with a lower quality setting, but this only solves the transit problem, as they will once again take up large amounts of memory once they are decoded by the browser for display. It would be nice to detect images higher than a certain pixel resolution and then down-scale them in addition to re-encoding images with low-quality JPEG encoding.

[gonfunko]

Agreed this would be nice; I added the following to my config to partially achieve this:

OnContentType=image/jpeg
OnCode=200
IgnoreUrl=webdav
AddConvert=convert
AddConvertDest=jpg
AddConvertArg1=-resize 500>
AddResponseHeader=Content-Type: image/jpeg

This will resize JPGs to be no larger than 500px in any dimension while preserving their aspect ratio. Additional rules for PNG or other formats can be added similarly. This does have a couple drawbacks though:

• I believe it's run for every image, even if the dimensions are already smaller and it's a no-op
• It requires a separate ImageMagick invocation, vs doing the compressing and resizing in one operation

[atauenis]

I agree that this will be a nice feature. This needs a large amout of work, but not impossible.

At least, it is need to integrate something like Magick.NET into WebOne. This also should improve performance on other converting procedures (probably; only if Magick.NET is faster than calling external ImageMagick application, I have no experience with Magick.NET currently).