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On upload and replace: This can be configured with the “Immediately generated for” parameter when defining a format, as described above. Note that if a new format is defined with this setting, existing assets in the system must be republished to pre-generate renditions/qualities of the format for these assets.
Triggered from an automation: The automation step “Generate asset renditions” can be used to pre-generate renditions/qualities based on more complex conditions. For instance, an automation can be set up to pre-generate renditions/qualities for videos with a certain size or when an asset is published to a specific channel folder.
For most formats, it most likely suffices to rely on on-demand transcoding.
No matter if a rendition/quality is requested on-demand or pre-generated, it is never generated if it is already available. If the definition of a format changes, the corresponding renditions/qualities are automatically re-generated when they are requested again.
For most formats, it most likely suffices to rely on on-demand transcodingNote that renditions/qualities of a specific format can not be generated for all input file types. For instance, renditions/qualities of video or audio formats can not be generated for image assets such as png, jpeg, and webp since it does not make sense to create a video or an audio file from an image. However, renditions/qualities of image formats can be generated for most common input files.