Flexible Macroblock Ordering for Context-Aware Ultrasound Video Transmission over Mobile WiMAX

Table 1

Summary of important symbols used.

Symbol	Definition
𝑚	Slice index
𝑟	ROI index
𝑓	Frame index
𝐿𝑓,𝑟,𝑚	Length of slice 𝑚 in ROI 𝑟, frame 𝑓
𝐿	Average slice length
𝐿max	Max slice length
𝑟tot	Number of ROIs
𝑓tot	Number of frames per GOP
𝐼𝑓,𝑟	Number of slices in ROI 𝑟 in frame 𝑓
𝑁𝑓,𝑟	Number of pixels in ROI 𝑟 in frame 𝑓
𝜇𝑓,𝑟,𝑚	Quantization parameter(s) for slice 𝑚, ROI 𝑟, frame 𝑓
𝜋𝑓,𝑟,𝑚	Service class
𝑝𝐸	Generic probability of packet loss
𝑝𝐿	Residual probability of packet loss after RS coding
𝜌(𝜋𝑓,𝑟,𝑚)	Probability of packet loss for service class 𝜋𝑟,𝑚
𝐿𝐵	Generic mean error burst length (in packets)
𝑞	Transition prob. lossy→lossless (Gilbert model)
𝑝	Transition prob. lossless→lossy (Gilbert model)
ℒ(𝜋𝑓,𝑟,𝑚)	Mean error burst length for service class 𝜋𝑟,𝑚
𝐵𝑓,𝑟,𝑚	Encoding bits for slice 𝑚 in ROI 𝑟, frame 𝑓
𝑐	RS symbol size
𝑁	RS code block length (in 𝑞-ary symbols)
𝐾	RS data block size (in 𝑞-ary symbols)
𝑅𝐶=𝐾/𝑁	RS code rate
𝑅𝐶(𝜋𝑟,𝑚)	RS code rate for service class 𝜋𝑟,𝑚
𝑅(𝜋𝑟,𝑚)	Transmission rate for service class 𝜋𝑟,𝑚
𝑇𝑓,tot	Transmission time per frame
𝑥𝑖	Luminance of pixel 𝑖 in original frame
𝑦𝑖	Luminance of pixel 𝑖 in received frame