rescal flow to [-1,1]

[neauniko]

in gen_denseflow_npy.py : Following I3D data preprocessing, for the flow stream, we convert the videos to grayscale,and pixel values are truncated to the range [-20, 20], then rescaled between -1 and 1. We only use the first two output dimensions, and apply the same cropping as for RGB. but i dont see the operation '' recal flow from [-20, 20] to [-1, 1]'' Thanks for you work

[linchuming]

https://github.com/TencentYoutuResearch/ActionDetection-AFSD/blob/ed86a0df91e58baa7d78c796ed29cff82b1f3fa6/AFSD/common/gen_denseflow_npy.py#L84 use the denseflow will do the operation