Sequence input Layer with video frames for LSTM

Could anyone please elaborate on how to feed video frames to a sequence input layer? MATLAB documentation for sequence or time series data input to a network says: "Sequences or time series data, specified as a cell array of matrices. C is a N-by-1 cell array where N is the number of observations. Each entry of C is a time series represented by a matrix with rows corresponding to data points, and columns corresponding to time steps." My question is, how to create a sequence input layer for video data of N videos, where each video is composed of L frames of colored nXmXc images?

Thank you very much in advance