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RJ · 01-31-2005, 07:16 PM

Also, something I'd like to add regarding MPEG encoding of interlaced video (for vcd, svcd and dvd):

MPEG 1 does not support interlacing. That is why VCD has only half the vertical resolution, you just throw one of the fields away. Smoothness is gone, too, of course.

MPEG 2 does support interlacing. However, you always encode frames. In order to encode correctly you need to tell the encoder that it is interlaced (every encoder has an option for that), and, very important, which field comes first. Coz when you choose the wrong field order, the TV will display the latter one first, which results in a back-and-forth-like jittering. You can see that only on the TV (as the PC shows you both at the same time), therefore encode a small clip with bottom field first, and one with top field first, and watch it on the TV to see which field order the correct one is.

RJ

01-31-2005, 07:16 PM	#18
RJ Member (14 bit) Join Date: Feb 2000 Location: Offenbach/Main (Germany) Posts: 8,485	Also, something I'd like to add regarding MPEG encoding of interlaced video (for vcd, svcd and dvd): MPEG 1 does not support interlacing. That is why VCD has only half the vertical resolution, you just throw one of the fields away. Smoothness is gone, too, of course. MPEG 2 does support interlacing. However, you always encode frames. In order to encode correctly you need to tell the encoder that it is interlaced (every encoder has an option for that), and, very important, which field comes first. Coz when you choose the wrong field order, the TV will display the latter one first, which results in a back-and-forth-like jittering. You can see that only on the TV (as the PC shows you both at the same time), therefore encode a small clip with bottom field first, and one with top field first, and watch it on the TV to see which field order the correct one is. RJ __________________ All's right with the world when your PC is working right.