Quantcast Why not capture PAL at 768x576? - digitalFAQ Forum
  #1  
05-15-2021, 09:43 AM
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EmielBoss EmielBoss is offline
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The general consensus seems to be that PAL 8mm needs to be captured at 720x576, but this involves resizing to 4:3 (or setting the PAR to 12/11, in which case the player will resize). My settings for this are:

Capture.jpg

But why is capturing at 768x576 adviced against? In that case, no resizing is necessary, and the PAR can be square. Since the horizontal analog lines are a continuous signal anyways, it shouldn't matter, right?

PS. I don't care about burning the files to optical media, but I do want them to be universally playable; phones, tablets, streaming via cloud storage apps, VLC, etc.



Last edited by EmielBoss; 05-15-2021 at 09:59 AM.
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  #2  
05-15-2021, 10:42 AM
lollo2 lollo2 is offline
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http://www.arachnotron.nl/videocap/d..._cap_v1_en.pdf

Image format/resolutions of recordings in VHS format?
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  #3  
05-15-2021, 11:25 AM
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I can't say that I'm entirely following the PDF document, but thanks!

Are my settings up to snuff? I think I'm gonna go with square pixels, because I cannot for the life of me figure out how to set a non-square PAR (or DAR?) with Hybrid.
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05-15-2021, 11:46 AM
lollo2 lollo2 is offline
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Quote:
I can't say that I'm entirely following the PDF document, but thanks!
Sanlyn and LS explains something in the second link ;-)

Quote:
Are my settings up to snuff?
Sorry, I cannot help for the settings.
I never use (and do not know in deep) any GUI or similar: for my restoration flow I do everything manually. I write my AviSynth scripts and insert the filters I consider appropriate, in order to have the full control on what happens step by step, parameter by parameter. The same for the rare times I encode, I use a ffmpeg command line.
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05-15-2021, 11:53 AM
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Do you perhaps have general purpose scripts and FFmpeg commands (suitable for PAL Hi8) that you don't mind sharing?
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  #6  
05-15-2021, 12:12 PM
lollo2 lollo2 is offline
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There are several in my posts ;-)

Foe encoding I keep 720x576 SAR 5/4 and force DAR 4:3 if necessary (not square pixel, PAR=16/15)
If upscaling to HD I use 1440x1080 and add 240 borders each side: so square pixels (PAR=1) with SAR 16/9 and DAR 16/9

Attached 2 xls files; sorry some text is in italian, but may be you can find them useful.

Addendum: if you work with avi lossless files (HUffYUV and others) you may need to add to the the DAR with something like
ffmpeg -i <file>.avi -aspect 4:3 -c copy <file>_dar.avi
so any tools working with it will have correct info


Attached Files
File Type: xlsx sar_dar_par_upscale.xlsx (10.9 KB, 1 downloads)
File Type: xlsx resolution and aspect ratio.xlsx (10.2 KB, 3 downloads)

Last edited by lollo2; 05-15-2021 at 12:40 PM.
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05-15-2021, 05:12 PM
latreche34 latreche34 is offline
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Capture cards are like imaging sensors found in scanners and camcorders, They have a defined scanning frame resolution in pixels, It cannot be changed. All capture cards are made under the standard featured in that PDF file and capture at 720x480 (NTSC), 720x576 (PAL/SECAM) and 720x486 NTSC pro capture devices (added 6 black lines on top of the frame).

Some capture cards allow resizing on the fly while capturing by choosing other sets of resolutions but as you said it is advised against because the artifacts are baked in and cannot be reversed, Always capture in native resolution, save the master file and do whatever you want later, If something goes wrong you can go back to the master files.
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