RIFE插帧倍率

[qii1102]

希望开发者能增加RIFE插帧倍率选择，自定义插帧最低只能选择60帧，某些24、25帧的视频进行2×倍率插帧就足够流畅，并不需要直接插帧到60帧，进行2×倍率插帧还能降低处理时长，省去不必要的处理时间

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I hope developers can increase the selection of RIFE frame insertion magnification. The minimum selection for custom frame insertion is 60 frames. For some 24- and 25-frame videos, 2× frame insertion is smooth enough. There is no need to directly insert frames to 60 frames. 2× frame insertion can also reduce the processing time and save unnecessary processing time