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PlazzTT
17th January 2005, 00:52
Hi,

I've been recording music videos with my capture card and encoding them to XviD.

What I have been doing is somewhat time consuming: I make an AVS for each video, and do the first pass of an XviD encode with it. I then see what bitrate in given in the XviD status window at the end of the first pass. I usually enter in the second pass bitrate as about 50-60% of the first pass bitrate, and this gives good results. The quantizers in the final encode are usually between 3 and 5 for P frames and higher for the B frames (about 6 to 8).

This takes up a lot of time because I can't automate the encoding process, because I need to see what bitrate the first-pass has come up with each time. Now, seeing as I don't have a specific file-size I want to aim for, is there some easier way of encoding like this?

I was thinking of doing one-pass encodes with the quantizer set at 4 or 5, but I don't think this would give as good quality as a two-pass encode.

Any recommendations? Again, filesize and encoding speed/time is NOT important, as long as the method is somewhat automated, and it can adjust the second pass bitrate to be in the region of 50-65% of the first pass bitrate.

Thanks.

Ark
17th January 2005, 01:16
You can do the second passes setting a zone with weight at 0.50/0.60.

PlazzTT
17th January 2005, 02:57
Originally posted by Ark
You can do the second passes setting a zone with weight at 0.50/0.60.

OK, but I'll still need to enter a second-pass bitrate?

Ark
17th January 2005, 11:48
No, the zone setting should "overwrite" the bitrate setting.

PlazzTT
17th January 2005, 17:36
Originally posted by Ark
No, the zone setting should "overwrite" the bitrate setting.

Thanks, I wasn't aware of that. I'll give it ago.

EDIT: No, setting the zone weight to 0.60 makes the final bitrate 60% of what is in the second-pass bitrate box, not 60% of the first-pass bitrate.