ghosts in part of encoded file

[gosens]

I am encoding a DVB source (hockey, originally 544x480, 29.97,NTSC, Interlaced) to DVD (352x480, deinterlaced). Most of my encodes using the rather simple script below have come out fine. However, lately I have had two encodes where part of the game - maybe 20 minutes or so - shows ghosts as the players skate or the lines go by. There seems to be no difference in the source video from a problem part to a non-problem part; it is all originally interlaced and DVD2AVI doesn't suggest anything different at this part of the video.

I have tried both TMPG and CCE and both have the problem.

Here is my avs:

movie="wjc1978.d2v"
MPEG2Source(movie)
FieldDeinterlace(blend=true)
GripCrop(352,480)
GripSize(resizer="BicubicResize")
GripBorders()
converttoyuy2()

If anyone knows why this might be happening or can suggest any solutions, please let me know. Thanks.

-gosens

[sh0dan]

FieldDeinterlace(blend=true) produces ghosts. Try blend=false - or better (IMO) - KernelDeInt.

[Mug Funky]

the difference in the "good" bits and the bad bits is most probably the shutter speed used in the original recording.

blend deinterlacing will be least noticable if the shutter is set to the field rate (1/50 for PAL, 1/59.95 for NTSC), so the motion blurring from one field matches up perfectly with the next.

a lot of sports/action footage is shot with a much faster shutter to give the impression of more action (well, that's my guess anyway..). when this content is blend-deinterlaced you'll get very noticable ghosting (and it'll b0rk your encoder's motion search algos).

so yeah, use sh0dan's suggestion (or one of the custom deinterlace scripts hanging around here, which preserve loads of detail at the cost of VERY slow encodes :))

[scharfis_brain]

a lot of sports/action footage is shot with a much faster shutter to give the impression of more action (well, that's my guess anyway..)

I think, that they just use the output of the slow-mo-cams, reduced to 50i / 60i.

Most sports in I've seen here in Germany had always mixed the normal shutterspeed of 1/50sec and much shorter shutter times. This is due to switching between normal 50i cams and slomocams with realtime output.



[brainless mode on]
btw. a 300fps slowmocam with 1/300sec shutterspedd, would be Ideal for double-standard output.
just:
- blend 6 frames together -> PAL
- blend 5 frames together -> NTSC
[brainless mode off]

[Mug Funky]

oh yeah! i forgot aboot those slo-mo cameras. man, it'd be fun to have one of them. think about it! i'd do EVERYTHING in slo-mo!

btw, blending several frames together != motion blur.

there's awful dynamic range effects when that happens. overbright things turn grey rather than some rich colour. anyone who's seen HDRI 3d images compared to standard dynamic range images would see the difference...

i wish camera sensors/DSPs could give floating-point output... of course any TVs that supported this would burn out people's eyes :)

[scharfis_brain]

i'd do EVERYTHING in slo-mo!
even those things, you do NOT show others? :D :D :devil:

[gosens]

Thanks to all for the suggestions. Using sh0dan's suggestions I tried both KernelDeInt(0) and FieldDeinterlace(blend=false).

Blend=false is the one I kept because while it didn't have the greatest picture quality, the ghosts were gone. The footage is mostly 1970's and 80's anyway so the quality isn't great to begin with.

KernelDeInt(0) mostly dealt with the ghosts, but it looks like it took an eraser to the ghosts and left "shavings" at the perimeter of where the ghosts were. There were also some poor camera scene changes and other random effects.

No doubt I need to learn how to better use these and other filters to tweak the results.

Mug Funky, I will look for some other custom scripts to test (such as your funkydeint) but if you have any suggestions for high speed action please let me know. If they're good I might wait out the encode times but I'm already at 18 hours for a 5.5 hour DVD using simple scripts. And between bob() and weave and conniption and convolusion, this newbie's having a hard time figuring all this stuff out!

cheers,
gosens

[Mug Funky]

even those things, you do NOT show others?

ESPECIALLY those things :) hehe.