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[Glimmie]

The bulk of my movie library are DVHS rips from Dish network. Back in the day there were several options to get the MPEG stream out of a Dish box. Some these older *.ts files are true 1920x1080i MPEG2. The newer are 1440x1080i MPEG4.

I am getting judder which I did not have with VLC using an i3 cpu with 1g RAM to boot. The rather old version of VLC I was using was said to do native 1080i which later version did not support. My video card can output true 1080i as it's the pro version. So how does RO handle 1080i?

1) Does RO de-interlace and de-telecine the 1080i files within JRiver and present the GPU with a 1080P stream? Then the FX3800 will re-interlace to provided the selected 1080i output? This would be bad!

2) Or does RO simply pass the 1080i through as interlaced frames, which is what i want because I use a Teranex scaler on the output which makes 1080p for the projector?

3) Can RO output 23.98 or 24P directly? I can output 1080/24P HDSDI. I can't get 1080/60P HDSDI because that would need a 3gbs HDSDI  ard.

4) I am not adverse to buying a new video card but I like having the HDSDI option as my HT is HDSDI based.

Note I am an EE with 30 years of broadcast engineering so please be as technical as you want in responses. I know broadcast video inside and out.

My system is:
i7 870 4gb
Nvidia Quadro FX3800 SDI
30TB UNRAID gigE connected.

P.S. Still running MC19 but will upgrade to MC20 anytime now.

[Hendrik]

1) & 2)
Direct interlaced output is not something thats going to ever work very well in a PC. PCs work on progressive RGB frames, to convert to RGB, you basically need to deinterlace first, or all sorts of problems might show up with chroma.

3)
Of course you can output 23.976/24p directly, however not very easily from telecined material. madVR in  RO HQ can do  it, but not automatically, you need to tell it to apply IVTC.

4)
Unless a new video card also offers direct 1080p60 output for deinterlaced progressive content, its not going to make anything better.

[Glimmie]

1) & 2)
Direct interlaced output is not something thats going to ever work very well in a PC. PCs work on progressive RGB frames, to convert to RGB, you basically need to deinterlace first, or all sorts of problems might show up with chroma.

A PC doesn't really know the difference between interlaced and progressive frames. It's just a computer.  A GPU, well that's a different issue. Using a pro video card such as the Quadro FX3800 and with software written to handle interlaced frames, a PC can certainly do true true interlaced video. We do this all the time in the TV broadcast industry. Most effects systems these days are PC based.

Also note that this is a dual monitor system. Unlike some lower cost dual monitor video cards, the FX3800 has two discrete output channels. The desktop is totally independent from the SDI output which can also be used as a DVI or HDMI output. So the second output can be interlaced while the desktop remains progressive, even at a different resolution.

Now if OTOH JRiver only works in progressive frames, then that's the problem here. So I guess you are saying I need to setup JRiver ROHQ to do IVTC and set my graphics card to output 1080/24P? So it can easily output progressive to the desktop and interlaced to the second output. Both at different resolutions as well.

I also acknowledge that IVTC is difficult to do well in software considering the limited horsepower of PCs. That's why I like to use the hardware based Teranex processor to do the IVTC, which it does very well. But if RO is doing a mediocre job on the IVTC by default, then the Teranex is not going to fix it after the fact.

[mark_h]

Hendrik, Glimmie is an industry guy who is known well and appreciated at other sites, eg AVSForum for his knowledge and pragmatism.    As he says: "please be as technical as you want in responses"

[6233638]

I also acknowledge that IVTC is difficult to do well in software considering the limited horsepower of PCs. That's why I like to use the hardware based Teranex processor to do the IVTC, which it does very well. But if RO is doing a mediocre job on the IVTC by default, then the Teranex is not going to fix it after the fact.

If they're all movies, then IVTC is trivial.
ROHQ (madVR) handles this perfectly and will give you a 1080p24 output. Just set it to force film mode by default.
 
Deinterlacing is only difficult with interlaced video, not progressive content like films.
 
 
You won't get a true interlaced output from a consumer video card. You can output a 1080i signal, but the video is not going to be output as an untouched interlaced signal. It's going to be treated as a progressive signal that then gets interlaced by the video card.

[Hendrik]

A PC doesn't really know the difference between interlaced and progressive frames. It's just a computer.  A GPU, well that's a different issue. Using a pro video card such as the Quadro FX3800 and with software written to handle interlaced frames, a PC can certainly do true true interlaced video. We do this all the time in the TV broadcast industry. Most effects systems these days are PC based.

That may be so, but no consumer software or consumer hardware is designed for this. Like I said above, everything is handled in RGB at the display stage, and your source is quite likely YCbCr, with subsampled chroma even, and converting this without deinterlacing first is just asking for trouble, at least with the conversion techniques used in the consumer GPUs. No matter what "pro" hardware or software can do, but we're in consumer-world here.

A few people have asked for this before, and eventually they had some kind of success, but quite likely not without loss in the middle.

Unless your content is all actually telecined, and not in fact interlaced, and you can leverage madVRs IVTC to make "lossless" progressive content from it, there is no 100% solution, and I'm afraid the use-case is also much too fringe for us to be able to provide a solution.

[Glimmie]

That may be so, but no consumer software or consumer hardware is designed for this. Like I said above, everything is handled in RGB at the display stage, and your source is quite likely YCbCr, with subsampled chroma even, and converting this without deinterlacing first is just asking for trouble, at least with the conversion techniques used in the consumer GPUs. No matter what "pro" hardware or software can do, but we're in consumer-world here.

A few people have asked for this before, and eventually they had some kind of success, but quite likely not without loss in the middle.

Unless your content is all actually telecined, and not in fact interlaced, and you can leverage madVRs IVTC to make "lossless" progressive content from it, there is no 100% solution, and I'm afraid the use-case is also much too fringe for us to be able to provide a solution.

You're quite correct in that I have to work under ROHQ so may best bet seems to just let RO handle the de-interlacing and IVTC and go out at 1080P/24.

That VLC version I used was a fluke in that it do direct interlaced output. The later versions of VLC did not so I was locked into that old version. But no way I will go back as the JRiver interface is so much of an improvement over the VLC/CollectorZ kludge.

I'll just experiment and report back if I find any newer elegant solutions?

Thanks to all.

[mojave]

I thought I'd add to this thread since the previous posts are pertinent. I've had combing or dropped frames with interlaced content from 1080i television programs for a while now with ROHQ. With RO it works fine. This past weekend I did some testing with an NFL game to see what gave me the best quality and no combing.

I'm using a GeForce GTX 970 video card.

1. With ROHQ and madVR doing deinterlacing, I need to drop NNEDI3 chroma scaling down to 16 from 128 due to the performance hit. It also seemed like I would still get combing on occasion. I tried both film and video modes. DXVA decoding was off.

2.  I turned off madVR deinterlacing and turned on DXVA decoding. I still had combing.

3.  I installed a manual installation of LAV Filters, used ROHQ Custom, and turned on CUVID decoding and deinterlacing. This was a little better.

4.  I used YADIF deinterlacing in LAV Filters. This had no combing and looked great. Even though it says it is software, it had a performance hit with madVR showing dropped frames unless I used NNEDI3 16.

5.  I reverted back to ROHQ and turned off deinterlacing in madVR. I also turned off DXVA decoding. I added a madVR display mode of 1080i30. I could now use NNEDI128, had no frame drops, and had no combing. The picture looked the best to me. My projector showed it was getting 1080i.

Per Hendrik, #5 should be the worst choice. Why does it seem to work so well for me? Am I missing something?

[Hendrik]

DXVA decoding has no influence on deinterlacing. On or off, you still need your renderer (ie. madVR) to do deinterlacing.
CUVID is the only mode that does HW deinterlacing in LAV. In theory this should be the same deinterlacing as EVR / RO Standard uses.

Also, its no surprise that using HW deinterlacing requires you to reduce the NNEDI3 usage, as it does use the same resources, plus you have to upscale 60 frames instead of just 30.
The second part of course also applies when using YADIF or CUVID.

Interlaced output can work, but its usually not very stable, and highly depends on the display device if its going to be a smooth experience, which is why its not something I would ever recommend to anyone. It'll also suffer a major breakdown when you have mixed progressive/interlaced material, which many broadcasts seem to be.

[mojave]

Thanks. I was only watching about a minute over and over. I didn't realize that the material could be mixed. Also, changing channels to a 720p channel probably wouldn't work very well.

I've used a TV zone in the past with RO standard for it, but may try to use madVR profiles.