Because of a request in the project forum I researched the conditions for supporting WebP-images in the image-upload-feature. It was a sitting duck to adapt the existing code because creation a WebP-image works similar to the equivalent functions for GIF-, JPEG- or PNG-images. Furthermore I changed the file type detection for images because using getimagesize for this purpose is not recommeded anymore.
"Do not use getimagesize() to check that a given file is a valid image. Use a purpose-built solution such as the Fileinfo extension instead."
The file-type-check is now based on the MIME-type. As a side effect of this change it is theoretically possible to allow further file types to be uploaded.
I tested the functionallity in a testing instance of the forum. The upload-script accepts WebP-images generally and it also resamples to large source images with lossy compression. That way I downsized a to large source image (1384x1341px, 1.7 MB) to 1024x990px with a filesize of 123kB [^1] without any obviously visible compression artifacts, as it is common with highly compressed JPEG-images.
[^1]: The settings for uploading images in my testing instance allows images with dimensions up to 1024px and a maximal file size of 200kB.
Because of a request in the project forum I researched the conditions for supporting WebP-images in the image-upload-feature. It was a sitting duck to adapt the existing code because creation a WebP-image works similar to the equivalent functions for GIF-, JPEG- or PNG-images. Furthermore I changed the file type detection for images because using
getimagesizefor this purpose is not recommeded anymore.The file-type-check is now based on the MIME-type. As a side effect of this change it is theoretically possible to allow further file types to be uploaded.
I tested the functionallity in a testing instance of the forum. The upload-script accepts WebP-images generally and it also resamples to large source images with lossy compression. That way I downsized a to large source image (1384x1341px, 1.7 MB) to 1024x990px with a filesize of 123kB [^1] without any obviously visible compression artifacts, as it is common with highly compressed JPEG-images.
[^1]: The settings for uploading images in my testing instance allows images with dimensions up to 1024px and a maximal file size of 200kB.