GrofLuigi
16th October 2005, 03:43
Hello all,
The story: I suspected that the capture driver (BTwinCap) or my VCR shifts the field order on dropped frames (my setup is quite all right and I get no dropped frames without a reason - usually I could see a tape glitch that caused the drop). After such a drop, the following (up to 10) frames are somehow 'different' than others - i.e. the interlacing 'jaggies' are not so well defined and 'sharp', but kind of 'triangular', and the picture is fine, although kind of blurry. A screenshot would explain it better, but at the moment my HDD is filled with the filtered video, and when I fix this problem, I will make another capture and post if necessary (no requests for avi's, PLEASE, I'm on dialup!)
To cut to the chase: After capture, the video was cleaned by the following script (Avisynth 2.56 RC2):
---------------
AviSource ("d:\video\capture.avi")
KillAudio ()
Crop (16,0,0,-16, align=true)
AssumeTFF() # as a precaution, but obviously didn't help
Telecide (guide=2, post=0, show=false) # I guess this is the culprit
DeGrainMedian(limitY=2,limitUV=3,mode=1,interlaced=true)
DeGrainMedian(limitY=2,limitUV=3,mode=1,interlaced=true)
ConvertToYUY2 (interlaced=true) # captured with PicVideo v3.0.13 and it's YV12!
AddBorders (0,0,0,16)
BilinearResize (352,576)
----------------
, saved as avi and sent to CCE for encoding.
The problem: The field dominance changes! About 1 minute it's TFF, then BFF and so on... (verified with AssumeTFF().SeparateFields()). The header (or whatever it is) says it's TFF and it doesn't change (verified with Info ()). Same with the MPEG. The original doesn't change field dominance.
The stupidity: I didn't check the result thoroughly (or maybe have just hit some good parts) and deleted the original capture.
The dissapointment: I still haven't discovered the behaviour of my setup on dropped frames or how to treat them.
The irony: Trying to avoid one particular problem created it where probably it wasn't.
The question: Can I get away without recapturing? I have the filtered avi and the MPEG made out of it, but no original. Some header trickery, or avisynth, or... I returned the tapes to the friend whose it were (this is his wedding video) and promised him a DVD in a day or two. :) How to avoid making fool of myself?
Thank you!
GL
The story: I suspected that the capture driver (BTwinCap) or my VCR shifts the field order on dropped frames (my setup is quite all right and I get no dropped frames without a reason - usually I could see a tape glitch that caused the drop). After such a drop, the following (up to 10) frames are somehow 'different' than others - i.e. the interlacing 'jaggies' are not so well defined and 'sharp', but kind of 'triangular', and the picture is fine, although kind of blurry. A screenshot would explain it better, but at the moment my HDD is filled with the filtered video, and when I fix this problem, I will make another capture and post if necessary (no requests for avi's, PLEASE, I'm on dialup!)
To cut to the chase: After capture, the video was cleaned by the following script (Avisynth 2.56 RC2):
---------------
AviSource ("d:\video\capture.avi")
KillAudio ()
Crop (16,0,0,-16, align=true)
AssumeTFF() # as a precaution, but obviously didn't help
Telecide (guide=2, post=0, show=false) # I guess this is the culprit
DeGrainMedian(limitY=2,limitUV=3,mode=1,interlaced=true)
DeGrainMedian(limitY=2,limitUV=3,mode=1,interlaced=true)
ConvertToYUY2 (interlaced=true) # captured with PicVideo v3.0.13 and it's YV12!
AddBorders (0,0,0,16)
BilinearResize (352,576)
----------------
, saved as avi and sent to CCE for encoding.
The problem: The field dominance changes! About 1 minute it's TFF, then BFF and so on... (verified with AssumeTFF().SeparateFields()). The header (or whatever it is) says it's TFF and it doesn't change (verified with Info ()). Same with the MPEG. The original doesn't change field dominance.
The stupidity: I didn't check the result thoroughly (or maybe have just hit some good parts) and deleted the original capture.
The dissapointment: I still haven't discovered the behaviour of my setup on dropped frames or how to treat them.
The irony: Trying to avoid one particular problem created it where probably it wasn't.
The question: Can I get away without recapturing? I have the filtered avi and the MPEG made out of it, but no original. Some header trickery, or avisynth, or... I returned the tapes to the friend whose it were (this is his wedding video) and promised him a DVD in a day or two. :) How to avoid making fool of myself?
Thank you!
GL