Still having downconversion issues...are you out there RED?

[Joe Walker]

We shot some gorgeous 4K product shots of new GM cars. We transcoded them in REDCine to Apple Pro Res 422 1080 23.98. When played back through our Kona 3 card to a Blackmagic HD Link routed to a Apple 30" Cinema Display , the downconverted footage has massive jagged lines through it. I've got everything set up correctly:

1. Sequence is set to Apple Pro Res 422 1080 23.98, playback set to same.
2. Kona 3 is set to primary: 1080 23.98psf, secondary: 525i 23.98. (setting secondary to 23.98p has no effect)
3. HD Link set to play back both HD and SD to Cinema Display.

So far the only working solution has been to route the HD out of our Kona 3 to a Panasonic HD-150 DVCPRO HD deck, and then route that to our second Final Cut Suite and digitize it in at SD uncompressed. Any ideas would be welcome. Thanks.

 

[Clay Morrison]

Apparently you, me, and Leo are the only ones concerned...

 

[Finner]

I'm highly concerned but if no one from red wants to chime in then what do you do? With lack of red input on this it seems quite clear to me that they have no answer to this problem. So were pretty much all SOL for a while.

 

[Dj Joofa]

I'm highly concerned but if no one from red wants to chime in then what do you do? With lack of red input on this it seems quite clear to me that they have no answer to this problem. So were pretty much all SOL for a while.

Finner, the answer to this problem goes beyond simple low pass filtering as provided by the software/hardware solutions mentioned so far here on this forum. The good news is that some computer vision algorithms do exist that were developed to take care of similar problems and they might work here.

 

[Joe Walker]

I'm highly concerned but if no one from red wants to chime in then what do you do? With lack of red input on this it seems quite clear to me that they have no answer to this problem. So were pretty much all SOL for a while.

Finner this is the most re-assuring thing I've heard yet about this problem. I was beginning to think that I was losing my mind! I mean seriously, how are all these RED owners getting their footage compressed down to SD for DVD without either having major aliasing or just blurring out all the footage until there's nothing viewable?

 

[Andrew M.]

We shot some gorgeous 4K product shots of new GM cars. We transcoded them in REDCine to Apple Pro Res 422 1080 23.98. When played back through our Kona 3 card to a Blackmagic HD Link routed to a Apple 30" Cinema Display , the downconverted footage has massive jagged lines through it. I've got everything set up correctly:

1. Sequence is set to Apple Pro Res 422 1080 23.98, playback set to same.
2. Kona 3 is set to primary: 1080 23.98psf, secondary: 525i 23.98. (setting secondary to 23.98p has no effect)
3. HD Link set to play back both HD and SD to Cinema Display.

So far the only working solution has been to route the HD out of our Kona 3 to a Panasonic HD-150 DVCPRO HD deck, and then route that to our second Final Cut Suite and digitize it in at SD uncompressed. Any ideas would be welcome. Thanks.

Did you scale it down in REDCINE to 1920x1080 or you let it go out at 4K?
If you scale it down in REDCINE what scaling algorithm did you use?
I think I had similar problem some time ago, but resolved it.

 

[conrad gaunt]

If you can (ie, you have time), you need to use a good quality software resampler, speed is not everything. I`ve been downsampling 3k RAW files to SD for about seven years, no problem, ever. My background is in 3D programming, both realtime and non-realtime.
Real-time equipment is usually a compromise in quality. My downsampler, for example, will downsample 4k-> anything, no jaggies, ever, and will process 16bit TIFFs in floating point (or nearly any 8bit format, and AVI in the next few days). I`ve been throwing zone charts at it and all sorts.
It runs on Windows (3.1 and up!), Linux under WINE (I tested this) and almost certainly a MAC using similar compatibility software (rosetta?), or a dual boot system. I use Virtualdub to stitch 8bit output seq back together for encoding. I`ll add support for 16bit output soon (as a TIFF sequence) .
I wrote a version for my own use and have been trying to add an interface and encourage people to learn the difference between real-time orientated solutions, since Leo`s first post. I have no worries about downsampling, at all, but I`m also not time constrained when working which may be an issue for some. I`ll be mastering to 4k always, downsample will be at the end. I may call the tool Red Back Side? You don`t have to use my tool, but at least try it, it might ease your worries about an eventual solution coming along. I`ll be adding presets with cropping and black bars etc and eventually AVI output for people who might like using it, like me

Its good points:
- Freeware
- High quality downsampling in floating point, and ability to extract 16bit TIFF data
- Small. Just click and it runs, no installation
- It will not crash once you set it going (unless you run out of disk space overnight, but I`ll add a warning in a future update, or hit a corrupt image file, which is unlikely unless you download your footage!)


update: much better downsampler that supports a few formats:
www.northyorkshirecamerahire.com/tds48bit.zip

 

[Greg M]

Are you editing the proxies and then downconverting?

We are not having any issues downconverting our final edits to SD...they look gorgeous! We are exporting DPX sequences from Red Cine and then conform. We then downconvert inside our Smoke to SD. It looks great. Now, if we online from the QT proxies we see issues.

EDIT:
Just re-read your post...so you are playing your SD downconvert on a Apple display?
bad idea...try using an NTSC monitor.

 

[amrrahmy]

When played back through our Kona 3 card to a Blackmagic HD Link routed to a Apple 30" Cinema Display , the downconverted footage has massive jagged lines through it.

maybe I'm an idiot, but can't u connect two displays(or more)(like the 30" cinema monitors with a dual link video card or with two cards(they are less expensive then the kona 3 (i think?)))

u connect through kona only when ur outputting to an sd monitor, right?

and why are u using both kona 3 and a blackmagic hd link?

if ur using pixel to pixel with the 30" cinema, u need to change the resolution of the monitor to pixel to pixel, i think it's 1680x1050

if u try to input 1080 u get the aliasing, that's why it would work with 1080p and not 1050, go directly from the video card(s)

 

[amrrahmy]

that didn't come out right,

u only output through kona when ur not using a monitor.

okay, this sounds the same.

u output through kona when u cant use the video card.(that's it)

 

[Joe Walker]

Are you editing the proxies and then downconverting?

We are not having any issues downconverting our final edits to SD...they look gorgeous! We are exporting DPX sequences from Red Cine and then conform. We then downconvert inside our Smoke to SD. It looks great. Now, if we online from the QT proxies we see issues.

EDIT:
Just re-read your post...so you are playing your SD downconvert on a Apple display?
bad idea...try using an NTSC monitor.

Greg,
Please re-read my post, I never once mentioned anything about proxies. We checked it also on three NTSC monitors, lots of aliasing. Will try the DPX method though. Thats one thing we haven't done yet.

Apparently you, me, and Leo are the only ones concerned...

Yes Clay, it's just us, everyone else and their clients are watching back the final product on 1080p displays, nobody else owns an SD TV anymore, hehehehehehe......

that didn't come out right,

u only output through kona when ur not using a monitor.

okay, this sounds the same.

u output through kona when u cant use the video card.(that's it)

Wow......

I don't mean to get snippy, but posting this problem on this forum has become a joke lately. I guess for now we'll just stick with our current method which ties up two edit suites for output. Sorry I bothered everybody with this problem.

Meanwhile in SD land..........

 

[Häakon]

We are not having any issues downconverting our final edits to SD...they look gorgeous!

Mine too. I'm not saying these guys aren't experiencing problems, but I'm surprised that a few people have had seemingly a lot of difficulty with this. Nearly everything I've shot has gone to both SD DVD and Blu-ray, and I've never had any problems with aliasing or jaggies or other little gremlins running wild. The RED footage is better looking in those smaller formats than any other camera/codec I've worked with!

 

[Mike Prevette]

Haakon I'm in the same boat. Almost everything I've done has gone to SD at some point, and I haven't had any issues at all.

 

[amrrahmy]

Wow......

I don't mean to get snippy, but posting this problem on this forum has become a joke lately. I guess for now we'll just stick with our current method which ties up two edit suites for output. Sorry I bothered everybody with this problem.

u have a problem wiring ur system and blaming red for no reason.

routing from a computer through an analogue converter to a digital link for a computer monitor is not that smart (more like a joke, how did u come up with that?)

and u can use any number of external monitors using video cards, also u can change the settings a bit to make it output 720p and it would work with the apple cinema or any ntsc monitor(with the right settings).

and it was meant to be a joke, i'm just not that funny.
or u didn't get the joke, i'll go with that one.

and stop using expensive hardware like kona 3 with ntsc monitors, that's just nasty.

and since u dont have a nice preview monitor u should either consider a nice studio crt monitor(the colorist will love u) or the new 50" sharp aquos(colorist will only consider u as a friend), i think it would be available in the summer.

 

[amrrahmy]

also once u transcoded ur files to prores it's not red's workflow problem anymore.

not setting the wires and the settings right is not red's problem.

workflow problems are not for the complaint department.

adding a monitor to ur computer is not downconversion issues.

connecting an ntsc monitor for hd content is not best descriped as downconversion issues.

that's why no one was answering ur thread.

i was just trying to help dude.

 

[amrrahmy]

how are all these RED owners getting their footage compressed down to SD for DVD without either having major aliasing or just blurring out all the footage until there's nothing viewable?

one more thing, playing back hd files to sd monitors in realtime is not the same as encoding files to sd resolution for a dvd.

 

[amrrahmy]

also, reading from other posts on the forum, ur were trying to make sd files from hd content using a hardware conversion cuz ur having trouble with setting up compressor and getting aliasing.
u can simply adjust compressor settings, or if that's too complicated for u, u can also export the files from final cut.

how can u be an editor if u cant export files with the proper settings.

 

[laguun]

scaling and conversion requires knowhow of the working of digital interpolators. Being able to judge their quality is essential for anyone doing scaling.

I openly post here about flaws in reds postproduction pipeline which are not good (as the so far closed codec, FCP not being 4K, the lockout of the marketleading and most powerful postproduction systems), but bad downconversion quality is a qualification problem of the editor/postpro supervisor, not of red.

 

[Leo Ticheli]

I have a few points to add. I must say I'm very disappointed at our failure to find a solution here at RedUser.

1. I often shoot subjects that are challenging for NTSC, fine lines and high contrast. If you're not attempting to down-convert such material, you are not aware of the problems. By the way, I've seen the same problem on footage shot on 35MM film; it's not just a Red problem, but 35MM film is typically down-converted with very sophisticated hardware down-converters. I suspect many Red owners do not have such equipment.

2. Even those with lofty credentials have failed to do a really good job of down-converting such files via software. We put a sample file on our ftp server and NO ONE was able to down-convert it acceptably to my standards.

3. We've experienced the aliasing on a variety of monitors, including broadcast CRTs.

4. There is absolutely nothing wrong with our systems; we're not new at this.

5. If you are down-converting via Kona 3 or FCS and you find the results pleasing, you are either working with very favorable footage or you have low standards of acceptable image quality.

6. We're continuing to experiment with compressor settings, but the results are not acceptable so far.

7. All hardware solutions so far have produced dramatically superior results, except for one manufacturer, which proved worthless. The Kona 3 built-in converter is also very weak.

8. Some have looked at still frames and declared that there is no aliasing problem; the problem is with MOVING pictures, not still frames.

9. If you have a software solution, POST IT!!!

Best regards to all,

Leo

 

[Gunleik Groven]

Hi Leo.

Not questioning any thing you say, but I'd like to take a stab at it, just for kicks, with scratch. Where's the footage link.

I have btw seen the same problems, and I think - like Graeme - that softening prior to downconversion may give results. Wether they're acceptable is a totally different issue, but you can see some of the same issues going from 4k to 1080. I haven't really gone below 720 yet, but still in HD land it can occur.

But where's that problematic footy?

Gunleik