Video Content AdaptationQoS by using the tree algorithm Jaepil Han Jinho Choo Sunwoo Yang

Content  Introduction  Related Theory  Content Adaptation - Framwork - Implementation  The present works  Further works

Introduction(1/2)  The optimal tradeoff point between transcoding overhead(CPU cost) and storage needed for the various pre-processed content variants  Content adaptation involves creating different versions suitable for rendering by mobile devices from some original content such as a web page.  The decision engine will look for the best tradeoff among various parameters in order to reduce the loss of quality in various domains.

Introduction(2/2)  The decision engine will take into account the different types of context such as device capability profile, networking charateristics, user preference, and metadata about the content itself  We’ll implement the engine for bandwidth among networking charateristics.  Study the video content adaptation and implementation it by using the Tree algorithm

Related thoery(1/2)  Trees algorithm - is a connected undirected graph with no simple circuits - particulary useful in computer science for instance, it can be used to construct efficient codes for storing and transmitting data

Related thoery(2/2) - this algorithm is applied to the decision engine for the best tadeoff among various parameters in order to reduce the loss of quality in various domains. for example, frame dropping, coefficient dropping, PSNR, Bandwidth. The Applied Tree algorithm

The content Adaptation (1/5)  Framework

The content Adaptation (2/5)  Frame dropping (FD)  Selection of the skipped frame locations  Based on frame type or perceptual importance of the frames  Consider decoding-independent cases only  The first B, all B, all B&P, P frames dropping  Only a coarse level of target bit rate is achievable

The content Adaptation (3/5)  DCT coefficient dropping (CD)  Meet the target bit rate with a greater granularity  Percentage of rate-reduction to be achieved like a CD (10%)  Minimize the overall distortion by optimally allocating the number of dropped coefficients among blocks  find breakpoints that minimize the CD distortion while meeting the target rate as:  where and denote the rate required to encode block and the distortion, respectively, when the breakpoint value is used, and is the total number of blocks

The content Adaptation(4/5)  Implementation - Procedure

The content Adaptation(5/5)  Reference Info - reference value according to Bandwidth : FD(Frame Dropping), CD(Coefficient Dropping), PSNR  Parsing - reference Info is xml file format. So this file must be parsed  Decision Making - find adapted parameter by tree algorithm, Interpolation, Logic.  Adapt the bit stream parameter - generate the adpated bit stream parameter file

The present works(1/2)  Implement Parsing system (a) Top : xml file (b) Bottom : parsed data

The present works(2/2)  Implement the Interface - input the User Info(bandwidth) - display the value of the adapted parameter

Futher works  In Adaptation engine, - Implementation of Decision making : Find efficiently and accurately Optimized value - adapt the bit stream