1. A non-transitory computer-readable medium storing instructions that, when executed by at least one processor, cause a computing device to perform operations comprising: determining, utilizing a convolutional neural network, varying predicted playback speeds of frames of a digital video by generating between-frame speed up times utilizing custom network heads of the convolutional neural network; and generating a modified digital video with temporally varying playback speeds utilizing the varying predicted playback speeds of the frames of the digital video.