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Weird 720p 10 bit scaling problem…
Onlining a 720 23.98 project and I am getting weird results. I think it’s a bad card, but I wanted to run this by and see if anyone has seen this.
We are onlining a piece and I got to looking at it with fresh eyes today and it seems every clip that is scaled gets a pattern on it (it looks kind of like plaid, but there’s no plaid color just the pattern) when it is scaled above 100%. The DVCPro HD ‘offline’ scaled footage looks fine. The footage is originated on a Varicam and captured via HDSDI, 1200A, & Kona 2 @ 10 bit uncompressed. The big variable is that all of this footage was shot on white.
I am using FCP 5.1.2, Kona 2, QT 7.1.3, Kona v3.2. I did some further testing and it seems if I turn down the whites under the 3 way cc white value of 235, the pattern goes away. Perhaps this is a white value foul up?
Another weird thing, it’s not FCP. The quicktime file is clean, a scaled exported quicktime is clean when watching in quicktime or the viewer. if I export the scaled clips (reference movie) and watch it through Kona TV, the pattern returns, but the quicktime is clean. How can this happen? What does scaling have to do with this?
I trashed prefs, monkeyed with rendering bit depths and qualities, nothing changes it.
Has anyone seen this before?
Jeremy
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16 Replies
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What if you edit the clip natively (in 720P DVCPRO HD).
Apply the effects, moves ,etc.
THEN
change the sequence setting to 10 bit uncompressed and render or copy paste it into a new 10 bit UC sequence.
the 235 is an NTSC peak white value, so that seems very strange. DVCPRO HD from varicam has problems with solid colors. It is the single number one thing that breaks the codec down. I have seen it in several different instances.
Maybe you can edit natively and then just cpconvert and render the final, it might be simpler.
David
Peace and Love 🙂
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Thanks for the response.
The capture went fine in 10 bit. It’s only when I scale that the pictures break up. It’s really really strange.
Here’s a picture for reference. I darkened it a little in photoshop to make it easier to see. It’s a picture of my 20L5/1 since I cannot export this pattern (it’s not baked in to the media, it only happens on the 20L5 display)
Notice the pattern shows up on the collar of the white smock as well.
https://www.madayproductions.com/cc/pattern_Web.pct.zip
Jeremy
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Just a thought.
Is there a way for you to monitor the SDI output of the K2. The analog output is no where near the quality of the SDI op and you many be seeing anomolies in that D to A conversion.
How does an exported frame look in Photoshop.
FYI the link doesn’t open.
David
Peace and Love 🙂
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I got the image. No worries.
WOW! that is some freaky looking stuff.
See if you can output this via SDI to the 1200A and then play back the 1200A tape to the same monitor.
Send me a four to six frame FULL REZ QT file I can download and I can look at it through my K2, I have a JVC monitor, so we can narrow down if it is the monitor or the K2 and driver combo.
I’ll try to duplicate it here.
David
Peace and Love 🙂
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Here’s the link that i sent aja. There are two clips, one unscaled, uncompressed out of FCP and one of my monitor in DVCPro HD.
Jeremy
https://www.madayproductions.com/aja/
PS Thank you David for taking a look at this. I have a hunch I have a goofed up card unless this problem is systemic. For good reasons, I highly doubt it’s systemic to the AJA architecture. When you download the uncompressed clip, put it in a 720p23.98 10 bit timeline and scale it over 100% and see if it breaks up as previously pictured.
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Jeremy,
I can tell you that I have succussfully duplicated the problem on my system. Before I even performed the scaling I was seeing a lot of horizontal noise.
Not sure what is causing this but I can tell you that I can see the exact same problem on my system.
By jove! You’ve found a bug!
David
Peace and Love 🙂
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Jeremy,
I think this has to do with the HD-SDI out of the 1200A deck. Here is why I say that. I have some 23.98 720P varicam footage in my machine right now. It was captured via firewire.
I took one of those clips and droped it into a 10 bit UC timeline and blew it up and it was fine. I think that you should try to recapture the stuff via firewire (lossless) and see if you get the same results. If you need to go 10 bit UC then do all of you work in this codec, duplicate your sequence and change the compressor to 10 bit UC for the final render.
THis way you can shoot the squence back to the 1200A via firewire or SDI.
David
Peace and Love 🙂
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I guess that’ll be the work around for now until AJA can get it sorted. I took a break from working today and didn’t do any further investigation so I thank you kindly for confirming this.
What version of the driver do you have loaded?
Thanks again for checking all this out on your end.
Jeremy
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I’m on all of the latest drivers, software, OD, etc.
David
Peace and Love 🙂
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Darn, I was hoping a driver update would fix it.
David, I thank you again for going through the trouble. Let’s hope AJA can see this same problem tomorrow so they can work on a fix.
Jeremy
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