Practical and Scalable Transmission of Segmented Video Sequences to Multiple Players Using H.264

Abstract

We present a practical way to distribute viewports on the same video sequence to large amounts of players. Each of them has personal preferences to be met or is limited by the physical properties of his/her device (e.g., screen size of a PDA or processing power of a mobile phone). Instead of taking the naïve approach, in which sections of the video sequence are decoded and re-encoded for each of the clients, we have exploited advanced features offered by the H.264 codec to enable selection of parts of the video sequence by directly manipulating the encoder-generated bitstream. At the same time, we have overcome several practical issues presented by the fact that support for these features is sadly lacking from the state-of-the-art encoders available on the market. Two alternative solutions are discussed and have been implemented, enabling the generation of measurement results and comparison to alternative approaches.