Log in

View Full Version : DVD artifact question


benmanw
24th October 2012, 11:12
Hi,

I was hoping someone might be able to help me out. In trying to capture some clips from a DVD film

disk by using VirtualDub I have chroma issues coming through. The source frame is:

http://i1145.photobucket.com/albums/o516/benmanw/1_zps78dd0a43.png

Then i separated it into top and bottom fields:

http://i1145.photobucket.com/albums/o516/benmanw/2_zpsaa65a42b.png

Note the close-ups of the area indicated by green rectangle:

http://i1145.photobucket.com/albums/o516/benmanw/3_zpse6d0a3d1.png

My question is why comb artefacts occurred near the edges? In fact complementary chroma artefacts

occurred in the same positions of top and bottom fileds respectively. Obviously it has nothing to do

with intelaced or progressive scanning types.

Any assistance would be greatly appreciated.

Thanks in advance.

setarip_old
26th October 2012, 17:28
Don't be too sure that it's not the result of interlacing. I believe that the combing artifacts are only VISIBLE, as you say, "near the edges" - and are only visible BOTH at the juncture of motion and motionless parts of the frame(s) as well as the juncture of dark and light parts of the frame.

Try using a deinterlacer, or perhaps, a program such as good ol' TMPGEnc that includes a "ghosting" filter...

SquallMX
27th October 2012, 04:39
I remember having similar issues, the culprit was that the interlaced video 4:2:0 was decoded as progressive 4:2:0, if you're using AVIsynth make sure to put "ConverttoYUY2(Interlaced=True)" at the end of the script.