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View Full Version : How to enable hw IVTC on ATI card?

dZeus
27th August 2008, 16:07
Supposedly all newer ATI cards have hardware inverse telecine.

I've got no idea how to use or enable it though! One DVD in my collection has incorrectly encoded film material (24fps source with the pulldown fields encoded in the videostream). Whatever I try, display statistics keep indicating a playback framerate of 60 fps, which looks to me as if it's using the vector adaptive deinterlacer rather than IVTC.
I've tried both media player classic home cinema with EVR and VMR9, in combination with MS MPEG2 decoder (which uses DXVA to offload part of the MPEG2 decoding process). I've also tried WMP11, which also reports 60fps in 'statistics', when playing back this disc.

I've tried the following driver settings for my ati card:
'3to2pulldown' = 1 (default setting with catalyst 8.7 on my card)
'3to2pulldown_DEF' = 1 (default setting with catalyst 8.7 on my card)
'3to2pulldown_NA' = 0 (default setting with catalyst 8.7 on my card)

'VForcePulldown' = 1 and 0 (makes no difference in reported framerate for this disk).

Is there a sample video I can use to test whether HW IVTC is working for at least MPEG2 DVD material? Do I need to perform other tricks to enable HW IVTC?

My setup: ATI HD3650 AGP, Catalyst 8.7, Windows Vista.
HW deinterlacing works, DXVA for MPEG2, MPEG4 AVC and VC-1 decoding is all working properly... just no IVTC afaik!

Is the only option to go the software IVTC route with nVidia purevideo codec with software post processor filter, or the DScaler5_IVTC version? Please help!
ranpha
27th August 2008, 16:38
I assume that our DVD source is 24fps and your monitor is a LCD 60Hz? If yes, is IVTC really needed?
dZeus
27th August 2008, 16:58
I assume that our DVD source is 24fps and your monitor is a LCD 60Hz? If yes, is IVTC really needed?

correct (DVD contains film material with hardcoded 3:2 pulldown).
Is IVTC really needed? Not in this setup, but I'm evaluating IVTC capabilities of the ATI card. Do you suggest setting the LCD refresh rate to e.g. 75 Hz will enable IVTC?
DigitalDeviant
27th August 2008, 16:59
I assume that our DVD source is 24fps and your monitor is a LCD 60Hz? If yes, is IVTC really needed?

I think he's referring to hard telecined sources so yes, he needs to IVTC. I've don't have much experience with using it, ffdshow works well enough for me, but you can try enabling "Pulldown Detection" in the Catalyst Control Center (under Avivo video - Basic Quality).
ranpha
27th August 2008, 18:19
From my understanding about telecined films, a 24fps source that was telecined with 3:2 pulldown will not be IVTC'ed by ATI drivers if the video is played on a typical computer LCD monitors that operates at 60Hz. Am I right? IVTC will only be performed if the display card is connected to a 24fps TV.
dZeus
27th August 2008, 19:44
well I don't see any IVTC kicking in, so you might be right about that. However, I wonder if IVTC will kick in if my refresh rate is a multiple of 24 (e.g. 72 Hz). Will need to add a custom display mode to test that though.

I also wonder what setting VForcePulldown to 1 does, since I don't see any IVTC kicking in when I enable it.
ranpha
27th August 2008, 20:12
well I don't see any IVTC kicking in, so you might be right about that. However, I wonder if IVTC will kick in if my refresh rate is a multiple of 24 (e.g. 72 Hz). Will need to add a custom display mode to test that though.

I also wonder what setting VForcePulldown to 1 does, since I don't see any IVTC kicking in when I enable it.

For TV, if its EDID says that it supports 24Hz amongst the supported refresh rate, the drivers may perform IVCT to remove the 3:2 pulldown. For computer monitors, I am not really sure, never have a 72Hz monitor anyway.

edit: And if VForcePulldown is true to its name, if set to 1, it will forcibly do pulldowns for all kind of videos. Inverse telecine main function is to remove pulldowns, not applying them. Better set it to 0 if you ask me.
wozio
2nd September 2008, 10:51
From my understanding IVTC on GPUs is used only for hard telecine, so for recreating original frames from interlaced fields. For soft telecine it is not needed since it is already normal, progressive film frames.

I also saw this that streams from dvds are played always at 60 Hz even if source is film. I think this is standard, dvd should be always 60 Hz.
pitch.fr
2nd September 2008, 12:33
well I've got some 29.97 telecine mpeg2 .ts

I simply checked "detect pulldown" in the ATi drivers in 48Hz with Reclock, and it did the magic :)

only works in OVERLAY, though :(
wozio
2nd September 2008, 12:39
yeah sources from HDTV or remuxed from dvds may work this way, but when playing normal dvds with menus and extras in 60 Hz and film telecined from 24 Hz it is not that simple.
dZeus
6th September 2008, 08:09
well I've got some 29.97 telecine mpeg2 .ts

I simply checked "detect pulldown" in the ATi drivers in 48Hz with Reclock, and it did the magic :)

only works in OVERLAY, though :(

can you post your values of the driver settings that I mentioned in the first post? You can check them with DXVA Checker (right-click on an entry, select 'driver settings'). Thanks!
pitch.fr
6th September 2008, 10:42
default settings of the 8.x ATI drivers
dZeus
7th September 2008, 10:08
I wish to know what checking 'detect pulldown' does. Could you please post the values of the settings I mentioned in my first post? Thanks
pitch.fr
7th September 2008, 11:35
how could I know what it does, it's in the ATI drivers.

http://www.tomshardware.com/reviews/avivo-vs-purevideo,1492-3.html

ask teh engineers :D
dZeus
10th September 2008, 23:44
how can you know? by posting the values I mentioned in my first post if you look at them with DXVA Checker (after enabling 'detect pulldown'). THANKS!