Curious found with Vdub 1.6

[movmasty]

The 1.6 has the ability to show the size of a frame, well, in two,quite new movies(that i got for testing and will soon delete),
b frames(i guess they are) are 8 bytes in size! and there is motion, are not null frames.

These movies are encoded with DivX503b830, and one of two frames is always only 8 bytes in size: key-normdelta-delta8bytes....key

all the frames of 8 bytes differs from the preceding.

In fact the quality of this movies is quite good for their bitrate, long movies with big screen and good quality in 700mb.

What does this mean? how are possible frames of 8 bytes that are not duplicates of the preceding?

[movmasty]

unless vdub shows 8 bytes for all b frames even thought they are not 8 bytes...

[DigitAl56K]

This could be due to the packed bitstream format.

[fccHandler]

Yes, I believe the 8-byte frames are just placeholders. The actual B-frame data is grouped with its future reference frame. At least, I think that's how "packed bitstream" works... ;)

[movmasty]

hehe, ok thanks, so those guys of divx com didnt find the way to ultracompress the Bs