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fsphil / hacktv

Analogue TV transmitter for the HackRF
GNU General Public License v3.0
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--wss switch erases second half of picture information on line 23 #46

Closed Zcooger closed 4 years ago

Zcooger commented 4 years ago

The whole line contains only the tag. Example showing this error: wss_blank Example showing complete 23rd line: dvd_wss

fsphil commented 4 years ago

The WSS signal overlapped the video on the second half of line 23 so I just blanked it completely. It's difficult to say if this is an error, the specification (EN 300 294) doesn't mention video at all. There is just this:

For optimum decoder performance, it is recommended that this period is free from other signals.

Zcooger commented 4 years ago

Ok, I just base this ticket on my observations of my 3 DVD players and a DVB-T receiver output.

fsphil commented 4 years ago

Do they all use the same timing? Can you measure how many microseconds it is from the start of the line?

Zcooger commented 4 years ago

Sure. I will check it on every device I have.

fsphil commented 4 years ago

Ah wait, I think I found it. It should be 42.5μs