Reminder

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Description

Multi-video cases need a param to better control video_maxlen_per_video in a refined way so that we can balance the number of frames occupied by each video.
However we currently only have one param video_maxlen which sets a max number of frames globally for every video. And if we input massive multiple videos, it would just truncate some videos behind instead of trying to decrease the sampled frames of previous videos.

Thus we need a new param like video_maxlen_ttl to help set a total max number of sampled frames, and then divide it by durations of videos automatically to balance frames of each video. While video_maxlen remains its function.

To disable video_maxlen_ttl can be as simple as setting video_maxlen_ttl=video_maxlen*max_num_of_videos.

Pull Request

#7700