GH2 100Mbps Flow Motion v2 Patch - Banding & Blocking Be Gone!

Yes, I had the same issue with this test:


All of the band stuff in the last half of the video. None of the C100 AVCHD footage exhibited this artifact. It was edited in Premiere CS6. For the purposes of the test video, I transcoded to ProRes 422 HQ with the Windows version of 5DtoRGB. Worked fine, and when I replaced the footage, I noticed no visual difference at all.

I'm going to do a test between GH2 unhacked and Flow Motion to see if I can get the same patterns in both (to see if it's an AVCHD problem or simply a Flow Motion problem). As a side note, in Premiere CS6 under OSX Lion, the pattern appears at the beginning of the clip in full, and is then greatly reduced to the point of going away. This could be related to NVIDIA drivers under Windows (my MacBook Pro has an AMD graphics chipset).
 
Chris Adler said:
I found some noise patterns in my footage from my last shoot that I find very troubling. I've talked to others who have also experienced the same kind of noise where it shouldn't be. Seems at first glance to be Flow Motion related. I can upload a clip from the MTS file if that would help identify the problem. It appears in shadowy even textured areas of the image.

Has anyone noticed this? I talked with Roman and he had the same issues with Flow Motion and hasn't seen the same problem using Sanity 5. If it's not related to the hack I'd like to know.
Click to expand...

Can you elaborate on this? I noticed something like this on a video a couple of months ago, but put it down to the fact I've always had bad luck with noise on this camera.
 
TheDingo said:
...Is this a bandwidth issue ( not enough bits to record the dark gradations, that might be fixed with an external recorder ), or a sensor banding issue ?
Click to expand...

Neither. It only shows up in Premiere. Transcoding to ProRes fixes it, and you see not artifacting if you open up the original file in Windows Media Player. Only in Premiere CS6/After Effects CS6.
 
TheDingo said:
So transcoding to the Cineform CODEC would likely fix this too. ( I am Windows based, so Cineform NEO SCENE is what I've been using for the past few years )
Click to expand...

Transcoding to anything with software outside of the Adobe apps will fix this (so no Premiere/AE/Media Encoder). Or you could just not shoot with Flow Motion. I have been using Sedna and Apocalypse Now (CBrandon) and have not had this issue at all.
 
TheDingo said:
Does it make any difference if you disable hardware-acceleration in Adobe apps ?
Click to expand...

Tried that, and no. No difference. Also tried it on the OSX version (I'm cross-platform and Creative Cloud rocks). It's better, but slightly. The effect shows up at the beginning, then is reduced to the point where it's practically gone.

Very perplexing. I want to shoot the same situation with the GH2 unhacked, so I can point the finger at AVCHD in general, or Flow Motion specifically. None of the C100 AVCHD footage had this issue in Premiere.
 
My main NLE is Sony Vegas Pro ( so I won't see this ), but I am also a Creative Cloud subscriber ( $30/month for all the Adobe apps was too good to pass up ), and plan on getting up to speed with Premier and AE in the next year.
 
TheDingo said:
My main NLE is Sony Vegas Pro ( so I won't see this ), but I am also a Creative Cloud subscriber ( $30/month for all the Adobe apps was too good to pass up ), and plan on getting up to speed with Premier and AE in the next year.
Click to expand...

I think you'll like it. I used to be a big Vegas user, but I haven't touched it in years. Been Premiere since version 5 BETA (not Pro either).
 
Gary Huff said:
Fresno Bob, here's a rendered video that will show you the artifacting that we're discussing.
Click to expand...
I've heard about this Adobe CS6 decoding bug for a couple of months now, and what's funny is that I still haven't seen it with my own eyes. Could you tell me exactly when and where to look for it in this video? Honestly, I've watched it five times and haven't got a clue!
 
lpowell said:
Could you tell me exactly when and where to look for it in this video?
Click to expand...

The half-lit wall behind and to the right of the piano player, and the darkened wall behind the guitar player on the far right side of the frame. The walls have some mottling and posterizing that keeps changing as the video plays, while other areas that are better lit are completely clean.
 
TheDingo said:
The half-lit wall behind and to the right of the piano player, and the darkened wall behind the guitar player on the far right side of the frame. The walls have some mottling and posterizing that keeps changing as the video plays, while other areas that are better lit are completely clean.
Click to expand...
I noticed the flickering on the walls, but figured it was just bad lighting strobing with the shutter speed. Other posters have reported a "diagonal line artifact", but it's still a mystery to me. I've been hoping someone would manage to capture a still frame with a static, clearly identifiable artifact, and upload the original MTS file for analysis. So far, I haven't had any luck tracking down this issue, though several posters have reported seeing it happen with Adobe CS6, but not with CS5.5 or CS5 or other decoders. That would suggest it's a CS6 transcoding bug, but without a positive ID it's hard to say for sure. I recently installed Adobe CS6, so when I get some time, I may be able to track it down myself.
 
I'll check the raw footage where I've seen it and see if I notice it outside of Premiere. In the next day or so I can upload a sample where it happens in my footage.
 
Chris Adler said:
I'll check the raw footage where I've seen it and see if I notice it outside of Premiere. In the next day or so I can upload a sample where it happens in my footage.
Click to expand...

It's the strangest thing... I can't see the noise AT ALL when reviewing the original MTS files. However, what's beyond weird is when I play Flow Motion MTS files in VLC, just for a split second as it's buffering my footage when I first start to play it... the noise clearly appears just as it does after being encoded to H264- but just for a second.

It mostly appeared in my footage in slightly dim lighting, not dark and not light... but say where skin would go from light to shadow, in that grey area it would appear prominently.
 
Somehow I can spot it VERY easily now. I've seen plenty of GH2 videos where I can pick out that particular noise instantly when I see it. kind of one of those things that goes right over your head until someone points it out to you... and then you can't "unsee" it.
 
...I've upped the contrast and adjusted the exposure to amplify the Adobe Decoder Defect.

Notice the the diagonal area on the wall in the frame on the right ?

Artifact1.jpg
 
TheDingo said:
...I've upped the contrast and adjusted the exposure to amplify the Adobe Decoder Defect.

Notice the the diagonal area on the wall in the frame on the right ?
Click to expand...
Are those two consecutive frames from the same instance of the video, decoded by Adobe CS6? While I can readily see mottled patterns in the greenish-brown wall, there's nothing that stands out as a spurious "artifact". I'm not trying to be obtuse, but since I have no way of knowing what the video is supposed to look like, I'm not certain which patterns you're referring to. If Adobe CS5 and other players produce noticeably different patterns when decoding the same two frames, then there must be something different in how CS6 is interpreting the color values encoded in the MTS file.
 
You must log in or register to reply here.
Back
Top