The video sequence was encoded using TM-5 Encoder. Then the MPEG-2 bitstream was divided into packets (1 slice per packet). For the test cases "random marking" and "distorsion-based marking" a portion of packets was marked as "premium": in the "distorsion-based marking" we marked those packets that, if lost, would be recovered hardly, given a concealment technique in the decoder.
Then a loss pattern was applied to the not-marked packets in all test cases (of course in "no marking" all packets are not-marked). Damaged bitstreams were decoded by the ISO Reference Decoder which implements a simple concealment technique: it replaces the lost portion of a picture with the area taken from the previous picture at the same position. We tested two different premium share (10% and 20%) and two different channel conditions (7% and 15% of packet loss rate).
PSNR was computed on decoded-concealed video data from damaged bitstreams with respect to decoded video from the loss-free bitstream.
Such decoded-concealed video data were re-encoded in MPEG-1 to make these demo files: in fact the most famous media players (both in Windows and in Linux) does not read MPEG-2.
Click on numbers to open/download demo files (about 1 MB for each file):
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