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miifox
According to the document I shared earlier (and other info I found online), the main role of the equalizing pulses is to make sure the vertical sync pulse of odd-line fields trigger at the same time as the even-line fields, despite the horizontal triggers being half a phase late.
The problem is that with the horizontal and vertical syncs embedded in one signal, the TV detects a vertical sync when the horizontal sync's vsync integrator goes beyond a thrashhold. Hence, it's imperative that that thrashhold gets hit at exactly the same time both fields, which requires both to be discharged at the same time despite the capacitor in odd fields holding half a charge.
According to this logic, one would need 6 short blanks to discharge a half-charge capacitor fully.
Of course, the reason this peeked my interest is the potential to replace the 0-½ interlace pattern of traditional television with a 0-⅓-⅔ pattern, potentially increasing vertical resolution by 33%.
If my logic is correct this would require to increase the amount of short blanks from 6 to 8. This is assuming that one full syncless line accumulates 12 units of charge, and the maximum retardement we'd face would be 8/12th of a line.
The way to accomplish this would be to sacrifice one scanline for creating an extra half-line sync pulse. Yes, this would imply 287 and not 288 active scanlines, and would mean that our effective active resolution would be 1440x861 and not 1440x864. Details, details!
Then we can just shift the first blanking line post-equalizing pulse ⅓ and ⅔ instead of ½, and we'd get a 3-field interlacing sequence instead of a 2-field interlacing.
Interestingly, the implication is that if a digital system ain't aware of what the heck's going on, it'll show the first field correctly and then interpret both of the second fields as one odd-line field.
One small note on my research: i have no heck the idea what i'm talking about. The role of the equalizing pulses is ill-explained on wikipedia and the internet in general. But the clue of their role I found actually on the wikipedia page for the old British 405-line system which *lacked* them. It said they needed to be synthesized for integrator-type sync seperation systems (by the broadcaster or by the set) and was not needed for other types of sync seperation. So I googled "integrator+equalizing pulses analog video" and got what I needed.
I find in general info on non-525/625 video systems lacking, I'd love to know more about 35p, 180p, 441i, and other early video standards even if I'm never gonna find signals to test them with. Also did you know France had a monochrome 819i50 system at some point?
Oh well...
An image of the role of the syn…
The same image with some modifi…
The problem is that with the horizontal and vertical syncs embedded in one signal, the TV detects a vertical sync when the horizontal sync's vsync integrator goes beyond a thrashhold. Hence, it's imperative that that thrashhold gets hit at exactly the same time both fields, which requires both to be discharged at the same time despite the capacitor in odd fields holding half a charge.
According to this logic, one would need 6 short blanks to discharge a half-charge capacitor fully.
Of course, the reason this peeked my interest is the potential to replace the 0-½ interlace pattern of traditional television with a 0-⅓-⅔ pattern, potentially increasing vertical resolution by 33%.
If my logic is correct this would require to increase the amount of short blanks from 6 to 8. This is assuming that one full syncless line accumulates 12 units of charge, and the maximum retardement we'd face would be 8/12th of a line.
The way to accomplish this would be to sacrifice one scanline for creating an extra half-line sync pulse. Yes, this would imply 287 and not 288 active scanlines, and would mean that our effective active resolution would be 1440x861 and not 1440x864. Details, details!
Then we can just shift the first blanking line post-equalizing pulse ⅓ and ⅔ instead of ½, and we'd get a 3-field interlacing sequence instead of a 2-field interlacing.
Interestingly, the implication is that if a digital system ain't aware of what the heck's going on, it'll show the first field correctly and then interpret both of the second fields as one odd-line field.
One small note on my research: i have no heck the idea what i'm talking about. The role of the equalizing pulses is ill-explained on wikipedia and the internet in general. But the clue of their role I found actually on the wikipedia page for the old British 405-line system which *lacked* them. It said they needed to be synthesized for integrator-type sync seperation systems (by the broadcaster or by the set) and was not needed for other types of sync seperation. So I googled "integrator+equalizing pulses analog video" and got what I needed.
I find in general info on non-525/625 video systems lacking, I'd love to know more about 35p, 180p, 441i, and other early video standards even if I'm never gonna find signals to test them with. Also did you know France had a monochrome 819i50 system at some point?
Oh well...
An image of the role of the syn…
The same image with some modifi…
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miifox
miifox
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Litterally the first time in my life I found the actual info I needed in one of these stupid powerpoint presentations!
Oh well...
http://ggn.dronacharya.info/ECE2Dept/Downloads/QuestionBank/VSem/AWP/Section-D/Lecture_16.pdf
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miifox
miifox
For this pride month...
...yeah, I quickly needed to check the gamma for my camera, but none of the test patterns pleased me. So I made my own test pattern.
It's very busy (too many ideas) and not very professional (cause it's me) but have fun!
It's a video test pattern. Lots…
...yeah, I quickly needed to check the gamma for my camera, but none of the test patterns pleased me. So I made my own test pattern.
It's very busy (too many ideas) and not very professional (cause it's me) but have fun!
It's a video test pattern. Lots…
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miifox
miifox
Tried out "vegetarian cheese" today... not bad, not bad.
Bit too young for my taste but I definitly don't have the budget for old cheese right now and in fact, this is cheaper than any cheese; which is partially the reason I took it. Also, just curiosity.
I do like how hard they try to avoid saying "cheese" on the package; even tho I know it's for kinda a dumb reason.
A package of "plantaardige plak…
Bit too young for my taste but I definitly don't have the budget for old cheese right now and in fact, this is cheaper than any cheese; which is partially the reason I took it. Also, just curiosity.
I do like how hard they try to avoid saying "cheese" on the package; even tho I know it's for kinda a dumb reason.
A package of "plantaardige plak…
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The thing is already gaining pretty serious "early video editor" swagger... It can open it's own files, juggle around with (my own proprietary of course) edit lists, mark clips for deletion that it'll just skip in playback, easily-ish move around the whole clip; and now I slowly gotto think about the whole other side of the package, which is gonna be the tool to assemble these clips back together. Not bad of a progress for a few evenings work and about 300-ish lines of code!
The same video editor, with muc…
The same video editor, with muc…
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miifox
miifox
My PC is too potato to render video
Normal peopls:
Me:
A screenshot of an ugly video e…
Normal peopls:
- Get a better PC
- Use an older video editing package
- Downrender to a lower resolution
Me:
- Implement my own crappy video editor
A screenshot of an ugly video e…
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re: Also no that wasn't me, i only reblog 'artistic nudity' :bluefox_blush:, gross kink mention
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re: That one dumb 'french region' meme
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miifox
miifox
; Missing media descriptions
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I always seem to get the most obscure errors on my work's windows laptop... it's increadible how much bad luck I seem to attract, especially with this windows 11 machine
An empty windows teams notifica…
A shadow of a window, without i…
An error message about the wind…
An empty windows teams notifica…
A shadow of a window, without i…
An error message about the wind…
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miifox
miifox
My hobby? Giving memes on social media a round-trip like these... and inventing new fictional worlds out of mundane objects
A screenshot of a Tumblr post, …
A screenshot of a Tumblr post, …
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miifox
miifox
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