[xine-user] Odd choppy DVD playback with tvtime deinterlacer

[Ryan T. <pho...@mi...>]

I was playing one of my DVDs and I noticed some quite choppy output
while using the tvtime deinterlacer. When I examined the stream I
found that it seemed to be using a somewhat odd pattern of progressive
and interlaced flags.

The video is primarily interlaced using bottom field first field order
but several times it has an odd sequence of three frames. First a
progressive frame that has the repeat first field flag set, followed
by an interlaced frame that is encoded with the top field first field
order, finally there is another progressive frame with the repeat
first field flag. After this the video resumes a series of bottom
field first frames.

I am seeing this with current anonymous CVS version of xine-lib. My
setup is as follows:

Athlon XP 2200
Radeon 7500 AGP using VIDIX driver
Pioneer A07XL DVD
512M RAM
Linux with 2.6.5 kernel
SBLive using ALSA drivers included with kernel
XFree86 Version 4.4.0

The DVD I'm seeing this on is Sailor Moon S Disc 2 during the initial
opening sequence(Title 2 Chapter 2). You can find a short (4 meg and
around 4 second) sample that shows the effect at:

http://www.hamiltoncom.net/~pholan/sailor_moon_op_frag.mpg

I understand that this probably can't be fixed until the tvtime
deinterlacer has support for tracking the pulldown across progressive
sequences but I thought that the sample might be useful to the
developers. Also it seems odd that it introduces such noticeable shake.

Finally, I have also noticed frequent shifts in field order on some
of my other DVDs around progressive sequences. Most recently on
Steel Angel Kurumi.

I suppose any time there is an odd number of frames using the repeat
first field flag the field order has to shift in order for it to
display properly on a TV. I guess this is just another example of some
of the annoying obstacles MPEG2 encoders can put in the way of good PC
playback.

BTW, thanks to the all of the xine developers for producing a really
good multimedia player.

Sorry if anyone see's this twice I originally sent it from the wrong
email address. Also in the first copy I forgot to mention I am
seeing this with the Greedy2Frame and Greedy deinterlace methods. It
is present but less noticable with the Linear method.