  Adaptive bitrate streaming (ABR) has become thede factotechnique for
videostreaming over the Internet. Despite a flurry of techniques, achieving
high quality ABRstreaming over cellular networks remains a tremendous
challenge. First, the design ofan ABR scheme needs to balance conflicting
Quality of Experience (QoE) metrics suchas video quality, quality changes,
stalls and startup performance, which is even harderunder highly dynamic
bandwidth in cellular network. Second, streaming providers havebeen moving
towards using Variable Bitrate (VBR) encodings for the video content,which
introduces new challenges for ABR streaming, whose nature and implicationsare
little understood. Third, mobile video streaming consumes a lot of data.
Althoughmany video and network providers currently offer data saving options,
the existingpractices are suboptimal in QoE and resource usage. Last, when the
audio and videotracks are stored separately, video and audio rate adaptation
needs to be dynamicallycoordinated to achieve good overall streaming
experience, which presents interestingchallenges while, somewhat surprisingly,
has received little attention by the researchcommunity. In this dissertation,
we tackle each of the above four challenges.
