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fsphil / hacktv

Analogue TV transmitter for the HackRF
GNU General Public License v3.0
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PAL-FM changes #29

Closed neo7530 closed 5 years ago

neo7530 commented 5 years ago

Have tried some things with PAL-FM (Analog sat receiver) and got nothing good out of hacktv. Thanks to captain_jack i made some changes in video.c

.fm_deviation = 6000000, / kHz /

and

.video_level = 0.51, / Power level of video /

so i will have a video. But it is too bright. Gamma seems to have no effect to FM Video.

Zcooger commented 5 years ago

In https://github.com/fsphil/hacktv/blob/0a08c326ffcde86af0a0d57a5a411d58ff003ab5/video.c#L196 gamma setting should be 1.0, so the image black and white balance is normal (linear gradient remains linear on oscilloscope). Did you tried changing this gamma setting or somewhere else?

fsphil commented 5 years ago

Without a CCIR-405 pre-emphasis filter the FM video from hacktv will never look good, unless your satellite receiver has an option to bypass its de-emphasis filter.