Detecting DivX 5 "Pro" Features

[Shernand]

Hi everybody,
I just wanted to know if there's any way to find out which pro features (qpel, bidirectional, etc) were used to create an avi file, like a "Avi Pro Features Detector", or some other way.

Thanks in advance.

Br,
Shernand

[redcane]

Some of the things I would think are clearly shown in the file (B-frames), but others are just within the processing of the data, and the output data just looks better... To find the latter I think you'd need some complicated analysis of the data.

[N_F]

Originally posted by redcane
Some of the things I would think are clearly shown in the file (B-frames), but others are just within the processing of the data, and the output data just looks better... To find the latter I think you'd need some complicated analysis of the data.

You mean you can tell if a movie has been encoded with B-frames or without? I doubt I could, on the other hand, I've never tried.

[redcane]

The frame *has* to be marked as a B frame for the decoder to decode it. You just look at the frame header... As for other options (mostly psychoacoustic), there are no actual indications of it other than how the data has coded out.

[N_F]

Ok... so the header contains info regarding all the frames (or perhaps only B-frames)? Wouldn't that take quite some space? I was under the impression the header was pretty minimal in size.

[Nielchiano]

I think what he means is that before every frame is a small frame header, telling which kind it is (I, P, B, D) and some other stuff. To put that frame type, you only need 2 bits... so it's not too large...