Thread: SAR Question
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Old 23rd August 2016, 12:02   #4  |  Link
tebasuna51
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Quote:
Originally Posted by agressiv View Post
Trying to figure out what SAR to use when encoding 4:3 video with DVD as the source.
Quote:
Originally Posted by Sharc View Post
When your source is a 4:3 NTSC DVD with small black borders left and right, its PAR is probably ITU i.e.4320:4739 = 0.909709034.

- When you encode to mpeg4/AVC and crop the 2x8 borders the SAR should be 10:11 for the cropped 704x480 picture
To avoid confussion first use standard names.
If we accept https://en.wikipedia.org/wiki/Pixel_aspect_ratio :

DAR = SAR x PAR

SAR = Storage Aspect Ratio (here after the crop 704x480)
PAR = Pixel Aspect Ratio (the --sar x264 parameter 10:11)
DAR = Display Aspect Ratio (on screen 704x528, DAR 4:3)

If you want the --sar parameter for x264 the standard name is PAR, not SAR.

Quote:
Normally, I set the SAR to 8/9, and the output video would be 704x540. It looks the *same* as the source except for the crops on the side. However, MPC-HC reports this as SAR 176:135..
Like Sharc say when you need crop to 704 "is probably ITU", but Brother John say also:

"... you have virtually no chance to find out the real DVD PAR (i.e. the PAR used in the mastering process) for sure. It might be generic, it might be ITU. Black bars left/right are an indication for ITU, but you can’t be certain. Also the absence of bars might mean generic, but it’s no proof either."

Then seems than your DVD is a Generic NTSC 4:3, and seems right use a PAR of 8:9 (with the x264 parameter --sar 8:9) to obtain a screen image of 704x540 than is informed correctly like a DAR 176:135
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