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View Full Version : Interlaced video detected as Progressive?

n0an
24th November 2009, 10:17
Hello,

I have a PAL DVD9 which is Interlaced, but is detected as Progressive by meGUI. I can see the interlacing on the video, and I am unable to figure out the de-interlacer to use. MediaInfo detects it as Interlaced - BFF.

Frame rate : 25.000 fps
Standard : PAL
Colorimetry : 4:2:0
Scan type : Interlaced
Scan order : Bottom Field First

VOB Sample
http://www.mediafire.com/?2kynmioyyxe

I also wanted a guide on how to find the type of de-interlacing a DVD requires. What are the initial steps to decide what kind of treatment an interlaced video requires. I am sure once I get the basic steps down, reading the associated documents will help in a much better way.
J_Darnley
24th November 2009, 13:07
MediaInfo can only tell you how the file was encoded. That sample is progressive but it looks like it has been deinterlaced very poorly (frame blending and aliasing).
n0an
24th November 2009, 13:30
Indeed. Any way of removing those artifacts? Vinverse() isn't of much help either.

Also, in general, what are the initial steps towards deciding on a de-interlacer?
LoRd_MuldeR
25th November 2009, 00:43
Also, in general, what are the initial steps towards deciding on a de-interlacer?

Use your eyes!

Bitstream flags can only tell you how a video was encoded, but not whether the content actually is interlaced or not.

You will find that in reality most footage captured from TV broadcast is encoded interlaced, even movies that are 100% progressive and thus do not need deinterlacing.

It seems they blindly set their encoder to interlaced, even if it scarifies some coding efficiency...
poisondeathray
25th November 2009, 01:19
I also wanted a guide on how to find the type of de-interlacing a DVD requires. What are the initial steps to decide what kind of treatment an interlaced video requires. I am sure once I get the basic steps down, reading the associated documents will help in a much better way.

You can start with neuron2's guide
http://neuron2.net/faq.html#analysis
manono
25th November 2009, 07:42
I have a PAL DVD9 which is Interlaced, but is detected as Progressive by meGUI. I can see the interlacing on the video...
It's not interlaced. It was encoded as interlaced, 2 different things, as has already been mentioned. You do not see any interlacing in that video because there isn't any. It was converted to PAL 25fps from 24fps film by adding a frame every second, in the form of 2 fields every second. Then it was blend deinterlaced. That blending is, I suppose, what you see. At this stage nothing can be done.