8-Step Greyscale.
Posted: Sat May 26, 2007 5:26 pm
Here's the second .wav file I have created. It's also at 48kHz, 8-bit mono, 60 seconds of a NBTV geyscale pattern from black to peak white. This should result in a 400Hz line frequency with eight luminance steps. There is line sync, but no frame sync, being line-repetitive it shouldn't be needed. I will get around to the missing pulse in due course.
There are 120 samples per line, eight of which are used for the sync pulse (167uS) and each greyscale value is of 14 samples (292uS). Being 8-bit video a few of the greyscale values aren't exact, but within a small fraction of a percent.
The other thing of note is that on this PC it came out 'the right way up', sync was negative and white was most positive.
Again, I would very interested in any feedback.
Steve A.
I won't post any more until I know I'm heading in the right direction.
There are 120 samples per line, eight of which are used for the sync pulse (167uS) and each greyscale value is of 14 samples (292uS). Being 8-bit video a few of the greyscale values aren't exact, but within a small fraction of a percent.
The other thing of note is that on this PC it came out 'the right way up', sync was negative and white was most positive.
Again, I would very interested in any feedback.
Steve A.
I won't post any more until I know I'm heading in the right direction.