The chunk size of real video data varies around the given average bitrate.
To account for this fact in the fake adaptive data set, the chunk size varies
randomly with a given standard deviation. The standard deviation used for the
BandwidthProfileSimulator is based on the chunk size variation measured on the
1 hour playlist of real media.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=172068110
