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Fred Connors Jr
DG System Back Level
on Oct 25, 2007 at 1:25:05 pm

Hello Craig & Company

We have been sending spots to DGDropBox for several months now. We are seeing poor on air results at some stations. The stations claim to be taking SDI out of their DR SpotBox servers. It appears to us that the spots have an added 7.5 ire of Setup. Our blacks look washed out and lighter parts of the spot look blurred.

We compress the spots with the black set a 0 and the stations report that the spot's black is at 7.5

DG claims that their playback devices are not adding anything to the SDI out. They say it must be in our compression setting, or that Episode is adding the 7.5 Setup.

I have taken the MPG file we created with Episode and converted it back to an MOV file then played it back thru a KONA card, we observed no black level changes.

I know for a fact that Composite out of the DG System SpotBox has 7.5 added, but I cannot get anyone to confirm or deny that 7.5 is also added to the SDI out.

Any insight on this would be appreciated

Fred

The Troupe - Modern Media Design & Production


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Craig Seeman
Re: DG System Back Level
on Oct 25, 2007 at 5:24:36 pm

Are you delivering to a specific station or to several stations but only one is showing this issue?

You state poor results at "some" stations. Have you been able to view the same spot airing at two different stations.

If one station is good and the other isn't then I'd believe the issue is "station side."

I've delivered 0 black to DropBox and seen spots play on two stations and they looked identical (booth good) . . . this even though their specs say that you should add 7.5 black on your end. I may have raised black a smidgen (technical measurement of course) above 0 thinking that might "trigger" something.


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Craig Seeman
Re: DG System Back Level
on Oct 25, 2007 at 5:32:24 pm

BTW, I believe DG has changed color space from 4:2:0 to 4:2:2 as part of their spec. That shouldn't cause the issue you're seeing though.

BTW you can try checking encodes in VLC086c also. No scopes of course but it's good for an eyeball QC.


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Fred Connors Jr
Re: DG System Back Level
on Oct 26, 2007 at 12:49:27 pm

Thanks for the feedback Craig.

We have found the problem. And yes we are sending to 50 stations regularly. And yes we have seen the problem on all local stations.

All of DG's playback systems default to add Setup to the Composite output of their video card. Composite Setup On also adds 7.5 IRE of black to the SDI and/or Component outputs. DG will not acknowledge this but the supplier of the video output card has acknowledged it.

This is why things look bad.

We now use a proc-amp filter adjusting the Setup down, Video Level Down and Chroma Up to compensate for the 7.5 of back being added on output of the video card.

Fred

The Troupe - Modern Media Design & Production


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Craig Seeman
Re: DG System Back Level
on Oct 29, 2007 at 3:33:09 pm

It's interesting how DG says you should add 7.5 black on the content creation side. I've done near 0 (working in DVCAM for local cable spots) and they don't seem to have issues and my spots looked good.


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Anthony Miles
Re: DG System Back Level
on Oct 31, 2007 at 2:15:07 am

Fred, Craid, Great thread, Thank you!
Please help me avoid the same problem. Fred, is your footage coming in from analog source with setup already added?? I ask, as most digital sources usually have 0 IRE setup. Mine are digital, HD with 0 IRE black into an FCP sequence at 8 bit uncompressed 23.976. I am outputting this file as 8 bit uncompressed and nesting the file into an NTSC 8 bit timeline at 29.97. My blacks stay at 0 IRE for this, I am also adding Proc Amp filter (to bump blacks to 7.5) as DG asked for 7.5 blacks, which I usually never put on digital files for digital delivery as I know most devices add setup on analog output. They also asked for upper feild first in their mpeg files. Is ths right, I thought most systems use lower feild first for NTSC, my old Digisuite used upper first, I think???

Any how these spots are going to a remote market that I will never be able to see to spot check. If you could summarize the best practices for DG DropBox, based on your experience that would be a tremendous help. Best/recommended software for this encoding job??

Best regards,
Anthnoy Miles
Intel Mac, FCP6 Still on Tiger, Decklink HD extreme


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Craig Seeman
Re: DG System Back Level
on Oct 31, 2007 at 2:32:29 am

My sources are digital too. Usually DVCAM although I'm moving to XDCAM in the near future.

MPEG2 Program streams are usually upper field first so I just switch that in my Episode template for DG and it works. DG will contact you if they see an issue. They'll go through a testing procedure (upload 5 good test spots) before they let you start using the system.

The odd thing when I started testing with Pathfire with MPEG2 Transport streams (owned by DG now) they spotted the field switch "judder" and told me it was OK to keep it lower field first.

For black I just cheat my digital source up to the equivalent of 1 IRE (thinking 0 might trigger something on their side) and it passed through. My spots looked good so I've stuck with that setting.


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Anthony Miles
Re: DG System Back Level
on Oct 31, 2007 at 4:48:52 am

Craig,
Thank you very much. How about the 720x512 frame size. That is a bit mysterious to me. Any clue to what that odd frame size is related to and if I need to set it to that. Do you take a standard 720x486 or 480 file and set it in the encoder for 720x512 to resize??? Siimilar to changing the feild order? Any trick to that?

Thanks again,
Anthony Miles


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Craig Seeman
Re: DG System Back Level
on Oct 31, 2007 at 5:14:57 am

MPEG2 is normaly 720x480. In my template I have setting that crops 720x486 to that size.

720x512 is a setting that Pathfire uses. You "crop out" sort of like creating black letter box during encoding. You're not resizing the video image at all. That creates space in the verticle interval for Sigma encoding for VNR use tracking. You don't need to do that for TV spot distribution since you just need proof/certifcation that they aired.

It's important to note that for broadcast you're not changing pixel aspect ratio either (compared to changing not square to square for computer/web use).


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Anthony Miles
Re: DG System Back Level
on Oct 31, 2007 at 5:20:49 am

Thank you Craig.


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Fred Connors Jr
Re: DG System Back Level
on Oct 31, 2007 at 5:22:01 pm

Anthony

If you Proc the video to 7.5IRE your black level will be at 15 IRE when it hits the air.

We produce everything with digital 0 black.

You can not compensate for the DG added black with just lowering your black level, or as they said in he old days "Crushing the Blacks".

We found we had to adjust three levels with the FinalCut Proc filter to compensate.
Setup = -0.25, Video = -0.38 and Chroma = +1.05

It is not perfect, but it is much better than no compensating.

Fred

The Troupe - Modern Media Design & Production


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Anthony Miles
Re: DG System Back Level
on Oct 31, 2007 at 6:03:49 pm

Thank you Fred,
Intersting. Which software do you use to encode. I have squeeze, but have been lookking into episode, if I can get by with Squeeze that would be good.

If anyone has a preset for squeeze and DG that would be really helpful. as I am having trouble getting to 720x512.

Thanks so much for your help.
Anthony


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Fred Connors Jr
Re: DG System Back Level
on Oct 31, 2007 at 6:11:14 pm

A

We are using Episode. With help from Craig S. it works just fine, even better with variable bit rate.

I have Sorenson but I prefer Episode overall.

Fred

The Troupe - Modern Media Design & Production


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Craig Seeman
Re: DG System Back Level
on Oct 31, 2007 at 6:17:51 pm

And Squeeze wont do 720x512. I needed that spec for Pathfire. I told Sorenson about that and they didn't seem to grasp what Sigma encoding was about.

Episode has no problem. It's the most flexible encoding tool on the Mac and maybe even PC. I may give Rhozet a try (PC Program) but at $5K I don't think I'll buy.

BTW you shouldn't need 720x512 for spots, only VNR. Spots should be 720x480. I'll double check that but it's one spec I don't think they have any reason to change for spots.


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Craig Seeman
Re: DG System Back Level
on Oct 31, 2007 at 6:52:32 pm

Anthony,

I got the specs from DG and created a new template. I haven't tested it since I don't have spots going out at the moment. If you can get me your email address I can send you the Episode template and you can give it a try for me.


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Anthony Miles
Re: DG System Back Level
on Oct 31, 2007 at 6:57:04 pm

Thank you Craig.
email = anthony at 4thwalltvandfilm dot com


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Craig Seeman
Re: DG System Back Level
on Oct 31, 2007 at 7:08:59 pm

Sent it to you in a zipped file. Give it a test and let us know ASAP if it passes. If it fails let me know why and I'll have another go at it.


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Anthony Miles
Re: DG System Back Level
on Oct 31, 2007 at 7:11:50 pm

Thanks, got it. I will ty it. I actually have Squeeze so I am going to have to purchase Episode to make this work. Not sure if I was clear about that. I very well may end up purchasing Eposide today or tommorow. Is this for the pro version or does it matter??

Thanks,
Anthony


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Craig Seeman
Re: DG System Back Level
on Oct 31, 2007 at 7:22:24 pm

Squeeze can't do 720x512 Program streams. At least I didn't see a way. I told them about it and asked for it as a feature request.

Episode has a free trial but the encode is limited to 30 seconds. You could always give that a try and tell DG it's not to length. You're just testing the encode spec. If it meets spec you'll know you can buy Episode and it'll solve the problem.

Of course the day after you do that Squeeze comes out with an update.


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Sean McHenry
Re: DG System and Sorenson
on Jan 21, 2008 at 3:33:02 pm

I am currently looking at the MPEG2 encode section of the latest Squeeze and if you create a new encode setting in the MPEG2 section of Squeeze using the "none" under format constraints you can then set the frame size to 480 x 512. You can set other attributes as well. In our spec sheet from DG, it mentions 18MB/sec is the preferred total data rate. That isn't going to happen for us under Squeeze as the max is preset at 10,400Kbps. Still, that's better than a normal DVD so I suppose that would be OK since these aren't true HD spots.

Has anyone done and successful tests with Sorenson?

Sean
Smchenry@mjp.com




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Craig Seeman
Re: DG System and Sorenson
on Jan 21, 2008 at 4:53:27 pm

DG spec is 720x512. That's not just a frame size. The resultant encode has to have 32 lines of black at the top (480+32=512).

I don't think you can do that it Squeeze the last time I tried.

There's a patch for Episode that allows that. Also Episode can do 18Mbps.



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Sean McHenry
Re: DG System and Sorenson
on Jan 21, 2008 at 6:33:51 pm

I still don't see what they need 32 full lines for really but that's fine.

I used Avid FreeDV (one decent use for it anyway) to capture footage at my desk and export a 30 second test as a full rez QT file according to the DG time line requirements. Sorenson, although it allowed me to choose the above setting failed when it came time to actually squeeze the test anyway.

I see no current way to use Sorenson. Shame really as the automatic FTP from the out box would have been great anyway. I say we bang on Sorenson's door till the answer and I too will request this as a feature. We have about 10 editing suites here now and all the PCs, which is most now have Sorenson installed. Sure would be a good thing.

Thanks folks.

Sean McHenry


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Craig Seeman
Re: DG System and Sorenson
on Jan 21, 2008 at 6:44:27 pm

[Sean McHenry] "I still don't see what they need 32 full lines for really but that's fine. "

For a while they were "grandfathering" older customers with 720x480 but I believe that's ended.

I suspect they're using the 32 lines to embed something their (Vertical Blanking Interval) but I could be wrong on that.

Are you on Windows or Mac? I know Episode, with patch, works on Mac.
I'd suspect FlipFactory might work on Windows. I wonder if anybody has used Procoder or Rhozet to meet the 720x512 spec.

In any case, Sorenson does not do it.





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Sean McHenry
Re: DG System and Sorenson
on Jan 21, 2008 at 6:50:15 pm

I have an older copy of Procoder on my laptop. I suppose I could test that but I am pretty sure it will do the same as Sorenson and "expand" the video to fill all the lines.

On PCs here as out workstations. A few of the graphics guys, the 3 audio suites have Macs and we have one FCP suite right now.

We had looked at an Anystream solution for the whole plant once but I haven't checked on what they are doing for a while now.

Sean


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david bensman
Re: DG System Back Level
on Jan 20, 2008 at 8:12:20 pm

Does anyone have a Compressor setting they can share for posting to DG? It would be much appreciated...

Also, I am still confused about the 720x512 frame size. Is that something that can be accomplished in Compressor (as I've read that it's NOT actually resizing the image.

Also, my spec sheet from DG calls for 7.5 IRE, though I've read on the forum that people use 0 because DG adds setup. Any clarification?

Finally, the spec sheet calls for a Digital Audio Level high peaks at -20, which seems low to me.

I will go through "Test" phases with DG tomorrow but want to make sure I get my presents right.

Thank!



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Craig Seeman
Re: DG System Back Level
on Jan 21, 2008 at 7:56:11 pm

[david bensman] "Also, I am still confused about the 720x512 frame size. Is that something that can be accomplished in Compressor (as I've read that it's NOT actually resizing the image. "

The 720x512 file should be 720x480 plus 32 lines of black on the top.



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Bmoneymedia
Re: DG System Back Level
on Nov 9, 2007 at 2:48:57 pm

It's sad to see, but refreshing at the same time to see that I'm not the only one havign issues with DG. For a while i though i was just a novice idiot. Well, i guess the novice part is still true.
Is there settings within Episode that i can use to ensure proper black levels during my compression to mpeg2? Or should this be something I try to correct with After Effect Broadcast Filter? Or am I off on both?


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Blake Podhajsky
Re: DG System Back Level
on Nov 26, 2007 at 7:24:32 pm

I am also trying to submit spots to DG Fast Channel. I just downloaded Episode Pro with the intention of purchasing it once I figure out the settings. Is anybody nice enough to email me the presets for Episode or Compressor? blakepod@yahoo.com

And also, Fast Channel told me my spot did have to be 720x512. Is this hard to do in Episode?


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Bill Nelson
Re: DG System Back Level
on Jan 23, 2008 at 3:58:13 pm

Gentlemen, in my experience neither Sorensen or Compressor generates a genuine 4:2:2 color space MPEG stream... unless the .02 Compressor update changed something. I went around with the Sorensen tech regarding their implementation of 4:2:2 for about a week. Seems he was the last tech working there (so he said) and was unable to clarify why the choice for that format existed in the software but was not operative.

Episode rocks, as far as I can tell. Just bought the Flash extension yesterday for some web work. Very nice. I am a DG DropBox certified house because of Episode.



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Mark Spano
Re: DG System Back Level
on Jan 28, 2009 at 3:30:24 pm

FYI, I've been sending DG spots through the dropbox for a couple months now and have been using Squeeze to do it. I tweaked a preset and it passed their tests and have been certified with no problems. My spots once encoded come at 720x512, 4:2:2, and the extra black lines are at the top and bottom of the frame. I have never been told or advised to make them all appear at the top - not sure what that's about, but as I said I've never had issues submitting spots this way. If anyone wants my preset, I can email you (it's all of 8K or so)...



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Craig Seeman
Re: DG System Back Level
on Jan 28, 2009 at 4:23:42 pm

[Mark Spano] "My spots once encoded come at 720x512, 4:2:2, and the extra black lines are at the top and bottom of the frame. I have never been told or advised to make them all appear at the top - not sure what that's about, but as I said I've never had issues submitting spots this way. If anyone wants my preset, I can email you (it's all of 8K or so)..."

DG has accepted this? The lines are supposed to be at the top only as VBI (vertical interval blanking). Seems they're changing their standards again. Before Episode had the VBR I feature, I tried what you did using Episode (512 top and bottom lines) and they flatly rejected it.




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Mark Spano
Re: DG System Back Level
on Jan 28, 2009 at 5:25:26 pm

All I know is that I did the whole certification process before even coming here and it was never suggested that the blank lines were to be all top. I was certified as of 12.18 last year, and they even asked for my Squeeze preset when it was through.



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Luke Danielson
Re: DG System Back Level
on Feb 5, 2009 at 5:33:56 pm

Hey Mark. Could I possibly get that Squeeze preset from you? I'm trying to get DG certified and have squeeze, but am having some trouble.

This would be GREATLY appreciated...

my email is dani0345@gmail.com

-Luke Danielson

Thank you so much....



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