Unfortunately, there's no convenient variable like w or tw for accessing the input's duration.
This thumbnail image will be a JPEG file. Let's test the drawtext filter by extracting the thumbnail image from the beginning of the video and writing "Test Text" to the center of this image. To write a piece of text onto the thumbnail image, use the drawtext video filter. Connecting multiple filters forms a directed graph called a filtergraph. When a filter finishes modifying the input media, it outputs the result, and this result is piped to the next available filter as its input. A video filter modifies/transforms the media streaming through it, and it is specified with the -vf option. If the -ss option is not provided to the ffmpeg command, then by default, the frame will be extracted from the 00:00:00.000 ( hour:minute:seconds.milliseconds) timestamp.ĭraw the title and duration onto the thumbnail image via the drawtext video filter. The -ss option ("start timestamp") allows you to pick a timestamp within the video from which to extract the single frame from. The thumbnail only requires an image of a single frame. To generate a thumbnail from a video with ffmpeg:ĭecide on a frame to extract the thumbnail image from via the -ss and -vframes options.
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