Activate WebP as default format for ImageVault UI

Note

BREAKING CHANGES

Animated GIF files will loose animation in current version. There is a bug (#15319) regarding this issue

If you would take advantage of the WebP format when browsing the ImageVault UI site, so that all thumbnails used in the UI are using the WebP format, follow the procedure below.

Configure defaultMediaFormatOutputType to use the WebSafeWebP format by adding the following appSetting in the ImageVault UI web.config file.
```
<add key="iv:defaultMediaFormatOutputType" value="WebSafeWebP"/>
```
Restart the ImageVault UI site.
When starting up, if the search index service is active, a background job will be queued to reindex the search service to use the new thumbnail formats.
Enqueue the "Convert all assets job". This will make sure that thumbnails for the new formats are generated. (this is an optional step but increases performance when completed)

Prerequisites

For ImageVault UI, you must upgrade to version 5.24 or later
For .net framework clients, you must upgrade to ImageVault.Client v5.22 or later
For .net/core/standard, you must upgrade to ImageVault.Client v6.1 or later

If you would like to have more granular control over the webp conversions, use the declarative syntax with attributes to retrieve specific conversions.

WebP

WebP is an image file format developed by Google intended as a replacement for JPEG, PNG, and GIF file formats. It supports both lossy and lossless compression, as well as animation and alpha transparency.

Google announced the WebP format in September 2010, and released the first stable version of its supporting library in April 2018.

Wikipedia

As format, it mostly generates images smaller in file size without any visible loss in quality.

When it comes to support in web browsers, it works with most newer versions. It currently (2022) lacks support by Safari on older macOS systems. See https://caniuse.com/webp for a more comprehensive report.