Where Do Video Thumbnails Come From?
Drop in a video file and the task list shows a thumbnail — not a generic video icon, but an actual frame pulled from that specific file.
Why the 10%-duration mark instead of the first frame
Many videos open on a black screen, a fade-in transition, or content that hasn't stabilized yet — grabbing the first frame consistently would often produce a blank or blurry thumbnail. Seeking to roughly 10% of the duration usually lands inside the actual content, giving a more recognizable thumbnail that helps identify which file is which in a batch.
Does thumbnail extraction cost extra processing time?
Thumbnail extraction and the actual transcoding are separate processes. Extraction uses the browser's native video decoding to load a single frame, which is far lighter than a full transcode and has no meaningful impact on compression speed.
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