+ # Set a origin source time (starting time of the chunck to copy
+ # here) We set it as the current time minus a multiple of CL to be
+ # consistent with the "rolling" caterpillar
+ t = torch.arange(fb_start.size(2), device=fb_start.device)[None, None, :]
+ src_time = fb_start * (
+ t
+ - CL