Feature: #88537 - WebP image format support for Image Processing

See forge#88537

Description

WebP [https://en.wikipedia.org/wiki/WebP] is a modern image format for the web that comes with several advantages over PNG or JPEG image files:

  • WebP images have roughly 30% smaller file size compared to JPEG or PNG files

  • WebP images support an alpha channel (transparency) which JPEG files do not support

WebP is support by all modern browsers [https://caniuse.com/webp], and is available for processing / generation in most ImageMagick / GraphicsMagick versions.

TYPO3 can now generate WebP images, if the underlying ImageMagick / GraphicsMagick library supports WebP.

Impact

By default, WebP images can now be generated, as TYPO3's configuration setting :php:`$GLOBALS['TYPO3_CONF_VARS']['GFX']['imagefile_ext'] is now extended with "webp".

Integrators can now use the file extension webp in their Fluid template or Fluid templates or PHP code when interacting with the underlying Processing API or the Graphical Functions API.

The Install Tool / Environment Module displays if support for generating WebP image files is possible. In addition, a new report in the System > Reports module of TYPO3 backend shows, if TYPO3 is properly configured for generating WebP image files.

If the underlying ImageMagick / GraphicsMagick library is not built with WebP support, the server administrators can install or recompile the library with WebP support by installing the cwebp or dwebp libraries.

The default quality of generated WebP image files can be defined via $GLOBALS['TYPO3_CONF_VARS']['GFX']['webp_quality'] which requires a value between 1 (low quality, small file size) and 100 (best quality, large file size), or set to lossless which uses the lossless compression format. Even lossless compression for converting, for example, PNG files will result in smaller file sizes as WebP [https://developers.google.com/speed/webp/gallery2].

Depending on the target audience of the TYPO3 Frontend, it may be valid to disable WebP support by removing "webp" from the imagefile_ext setting.