Psvbi
From M1Research
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===Base Theory=== | ===Base Theory=== | ||
| - | === | + | Data to transmit coded by 14 bytes block. Each block transmitted in one video frame. Data encoded as luminance part of video signal (most stable to MPEG encoding/decoding) in some video lines (in our case we prefer to use top 2..4 lines - not visible on home equipment, only professional monitors with turned on underscan area could be used to SEE if data real present). During coding data used <i>Hamming Error Correction Code</i> and permutations alorithms to make more stable transmitting data, but some times it was noticed false data detection :-(((, use control sum algorithms in analizator to check if it's your real data packed :-))). |
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| + | ===Embedding data=== | ||
| + | Embeddin data performed by <b>VirtualDub</b> software (real great program). Embedding and encoding data performed by <b>plug-in</b>. | ||
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===Demembeding data=== | ===Demembeding data=== | ||
===API interface for own analizator=== | ===API interface for own analizator=== | ||
Revision as of 16:00, 7 January 2006
psvbi - Pseudo VBI
Contents |
Overview
psvbi software complex was developed for trasmitting control commands in TV video signal. Data block coded into some lines of video signal and could be used as marks for remote stations or analytic system. It much easy to implement and control (and diag) instead of real VBI due to high cost of equipment.
How does it works
Base Theory
Data to transmit coded by 14 bytes block. Each block transmitted in one video frame. Data encoded as luminance part of video signal (most stable to MPEG encoding/decoding) in some video lines (in our case we prefer to use top 2..4 lines - not visible on home equipment, only professional monitors with turned on underscan area could be used to SEE if data real present). During coding data used Hamming Error Correction Code and permutations alorithms to make more stable transmitting data, but some times it was noticed false data detection :-(((, use control sum algorithms in analizator to check if it's your real data packed :-))).
Embedding data
Embeddin data performed by VirtualDub software (real great program). Embedding and encoding data performed by plug-in.
