SampleAVAFrames bug

[irvingzhang0512]

Thank you very much for your work!
I'm looking forward to your ava models in Nov.

SampleAVAFrames works fine if clip_len=32, frame_interval=2, like in the unittest.
But when clip_len=8, frame_interval=8, this function only returns 2 index, but 8 index are expected.

My guess is that length is not calculated in a proper way.

        length = len(
            range(-self.frame_interval,
                  -(ori_clip_len + 1) // self.frame_interval, # should divide by 2 instead of self.frame_interval
                  -self.frame_interval))

        length = len(
            range(0, (ori_clip_len + 1) // self.frame_interval, # should divide by 2 instead of self.frame_interval
                  self.frame_interval))

[kennymckormick]

Yes, -self.frame_interval should not be the stepsize and there is a bug in the current code. Actually, I think the current implementation of get_clips is too lengthy. I provide a new implementation in PR #317 (under review now). You can check that for reference.