oyvindln / vhs-decode

Software defined VHS decoder - Fork (maybe temporary) of the ld-decode Laserdisc rf decoder
GNU General Public License v3.0
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Added VHS-HQ format (level shift for one track) #112

Closed Stefan-Olt closed 1 year ago

Stefan-Olt commented 1 year ago

This adds the VHS-HQ format, which is mostly compatible with VHS, but shifts the level every other track by half of the horizontal line frequency. This can cause a small, but visible, brightness difference between odd and even fields. The VHS-HQ format will compensate that shift resulting in more uniform fields (only implemented difference to the standard VHS format).

Even though the the same shift is defined for S-VHS, it is currently not activated for this format, as the not yet implemented sub-deemphasis changes the levels in a non-linear way and it's currently no improvement.