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beorn_d_latch
7th May 2007, 00:25
Hi,

I have a question:
For PAL:
it seems that dgmpgdec is not so correct concerning the field order (interlaced or deinterlaced)of the source material(the dvd).
I use gordianknot to encode my video's (because autogk uses a too loose (GMC and Qpel)or too strict xvid settings(no GMC and no QPEL)).
But everytime i have to start a encode in autogk because it analyzes the source material (i think with an avs script) and there i then can see if my source material is truly interlaced or not.
You can understand this is some kind of a hassle...

Is there a sure way to check if source material is truly interlaced or does anyone know how autogk does it?

Thx in advance

neuron2
7th May 2007, 01:46
We've discussed a thousand times what DGIndex reports and it is clearly described in the user manual. From the manual:

"Frame Type - Displays Interlaced or Progressive depending on the value of the MPEG2 progressive_frame flag. Please be aware that this merely describes how the frame was encoded; it says nothing about whether the content of the frame is progressive or interlaced. It is common for progressive video to be encoded as interlaced, and vice versa."

You have to separate the fields and inspect them, looking for the typical signatures of progressive or interlaced video.

So if you have an issue with AGK, you should post over there. Moving to AGK forum.

manono
7th May 2007, 09:01
Hello and welcome to the forum,

I use gordianknot to encode my video's (because autogk uses a too loose (GMC and Qpel)or too strict xvid settings(no GMC and no QPEL)).

I don't think I understand. AutoGK uses neither Q-Pel nor GMC. If you don't want them, you should be happy. If you do want them, use something else like GKnot, so you can tweak the XviD settings to your liking. Neither Q-Pel nor GMC is necessary for a quality encode.

it seems that dgmpgdec is not so correct concerning the field order (interlaced or deinterlaced)

As neuron2 explained, DGIndex is perfectly correct. The problem is at your end because you, 1) didn't read the manual and, 2) aren't examining the frames yourself to figure it out. You don't really need AutoGK to do the job for you. A quick 10 second examination of the video in DGIndex should be enough to tell you if it's really interlaced or not.

beorn_d_latch
7th May 2007, 21:13
Thx for the replies:

a) "You have to separate the fields and inspect them, looking for the typical signatures of progressive or interlaced video"
--> how do i do that?? (if it's in the manual, where is it discribed how to inspect them?)

b) Does anyone know how autogk does it? ()

it uses a script (avs):

LoadPlugin("C:\PROGRA~1\AutoGK\DGMPGDec\DGDecode.dll")
LoadPlugin("C:\PROGRA~1\AutoGK\filters\decomb.dll")
file="E:\twin peaks dvd1 workplace\extra 1\tempor\agk_tmp\interlace.log"
global sep="-"
function IsMoving() {
global b = (diff < 1.0) ? false : true}
mpeg2source("E:\twin peaks dvd1 workplace\extra 1\tempor\agk_tmp\extra 1.d2v")
c = SelectRangeEvery(18,18)
global clip = c
c = WriteFile(c, file, "a", "sep", "b")
c = FrameEvaluate(c, "global a = IsCombed(clip, 32)")
c = FrameEvaluate(c, "IsMoving")
c = FrameEvaluate(c,"global diff = 0.50*YDifferenceFromPrevious(clip) + 0.25*UDifferenceFromPrevious(clip) + 0.25*VDifferenceFromPrevious(clip)")
crop(c,0,0,4,4)


and this generates a file which contains something like this:

false-true
false-true
false-true
false-true
false-true
false-true
false-true
false-true
false-false
false-false
false-false
...

by this autogk decides if it's interlaced or not:
(if someone could explain how i could maybe write a java-prog which does it for us).

thx in advance,
(btw this is a dvd which I own!!!)

beorn_d_latch