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Formats that start with “Internal” in their names are internally defined formats that are used as intermediate steps. An example of this is the “Internal Thumbnail” format, which is e.g. used when creating video thumbnails. In particular, to generate a rendition quality of an image format for a video, a rendition quality of the internal format “Internal Thumbnail” is first generated, and then a rendition quality of the targeted image format is created.
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