Block Dropout Detection

For detecting a broad range of digital tape dropouts, originated from tape formats different to Digital BETACAM™, a more general detection algorithm was developed. Similarly to the before mentioned type, they may also occur during the migration process, but have a different appearance. Instead of a chessboard structure, these dropouts appear as blocks or horizontal stripes within a constant block size. They need to be found during migration of content into IT based storage systems, as later detection and repair causes higher costs due to the need of re-ingesting tapes or is even impossible when tapes are further degraded.

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Sample frame affected by block dropouts. © ORF

Within the DAVID project JOANNEUM RESEARCH developed a Block Dropout detection algorithm which is able to find block dropouts in one or multiple frames of the video. An automatic grid detection algorithm allows for the detection of the block size and its corresponding regular block grid location.

Block grid found by the DAVID block dropout detector prototype © JRS
Block grid found by the DAVID block dropout detector prototype © JRS
Block dropouts found by the DAVID block dropout detector prototype. © JRS
Block dropouts found by the DAVID block dropout detector prototype. © JRS