Media Encoder Export Has Green Pixels In Highlights

[Kris Merkel]

Have you tried rending it out to a different codec to see if the export has the same characteristics? It’s just an artifact from a poor encoding pass and AME is making up for information that it missed or could not read.

Unfortunately while AME is quick and does a fairly decent job at most encoding jobs there are not a lot of options to really dig in a customize your settings.

Are you using CBR or VBR? Did you start with a preset? What are your bit rate settings and profile level ect?

You can also check your highlight level on the scope to make sure it is legal, not a necessity but can hurt.

“Think of everything in terms of building capacity.”

Kris Merkel
twitter: @kris_merkel
Product Manager, Flanders Scientific Inc.
http://www.shopfsi.com
Co-Founder, Atlanta Cutters Post Production User Group
http://www.atlantacutters.com

2.2Ghz MBP core i7
16Gb RAM
CS6/FCP7
AJA T-Tap
AJA IO XT
FSI LM-2461W/CM-170W

[Ben Mullins]

The original file exported from Premiere Pro is a DNxHD file, dropped into Encoder and sent out using VBR 2-pass at 25,000kbps with a profile of 5.1.

[Ivan Myles]

Were any colorization effects applied to the clip?

[Kris Merkel]

Is there a reason that you are encoding to DNXxHD and then re encoding to your deliverable H.264?

Try exporting the deliverable media right from the timeline to AME and use try the main profile at 4.2. Just export a small section of the troubled area so you can quickly troubleshoot the setting. Once you have nailed the settings export the whole enchilada. There is no reason with AME to encode to an intermediate codec before encoding your deliverable.

“Think of everything in terms of building capacity.”

Kris Merkel
twitter: @kris_merkel
Product Manager, Flanders Scientific Inc.
http://www.shopfsi.com
Co-Founder, Atlanta Cutters Post Production User Group
http://www.atlantacutters.com

2.2Ghz MBP core i7
16Gb RAM
CS6/FCP7
AJA T-Tap
AJA IO XT
FSI LM-2461W/CM-170W

[Ivan Radovanovic]

This is probably old issue with DNxHD, but nobody seems to care about it.
I started this thread long time ago:
https://forums.creativecow.net/thread/45/884228

https://twitter.com/#!/disample_dcc

[Ivan Myles]

Ivan, were all the luma values between 0-100 IRE?

[Ben Mullins]

Hi,

Thanks for the advice. I exported it from Premiere as an H264 .mp4 and it works fine so I’m guessing this is a DNxHD problem. It definitely looks like an issue with the luma values being too high but for me the problem isn’t apparent with the DNxHD .mov master file itself, but rather only when I try to re-encode from that master. I’ve tried re-encoding to a variety of codecs and wrappers and I get the same results each time, green noise in the highlights.

I’ve just switched from a Mac to PC and was going to use DNxHD as a replacement for ProRes when I export my master file. Is this a good idea? Is there a preferred option? Actually didn’t Adobe say that they have included ProRes encoding in CS Next?

Also, how do I check the numerical luma values in Premiere?

Thanks,

Ben.

[Bob Slenker]

it is interesting that you ask about applied color effects. this is a problem i have had periodically when using things like colorista and boris red effects.

[Ivan Myles]

[Ben Mullins] “Also, how do I check the numerical luma values in Premiere?”

Change “Composite Video” to “All Scopes” or “YC Waveform” using the tools menu in the bottom right corner of the Reference, Program, or Source monitor.

When I try using DNxHD with color level 709 the luma values outside of 0-100 IRE get truncated and then the remaining values between 0-100 get blown out to -7.5 to 109 IRE. Therefore, I stick with RGB color level.

Any luma or RGB values outside of 0-100 IRE will be clamped when converting to DNxHD, PNG, JPEG2000, or uncompressed RGB. I have not tested many other codecs, but uncompressed 4:2:2 YUV and H.264 codecs are OK. It is a good idea to view source files using the scopes prior to transcoding. The same is true for Premiere sequences, especially if exporting a file for color correction in a different program.

[Ben Mullins] “I’ve just switched from a Mac to PC and was going to use DNxHD as a replacement for ProRes when I export my master file. Is this a good idea? Is there a preferred option?”

ProRes, DNxHD, and GoPro Cineform commonly used. Here is a great comparison:

https://www.fallenempiredigital.com/blog/2013/02/28/avid-dnxhd-vs-apple-prores-vs-gopro-cineform-recompression-generation-loss/

AVC-Intra is another potential option. To the best of my knowledge ProRes will not be available on Windows; Adobe CS needs FCP or Compressor to provide the codec. In CS Next DNxHD MXF will be an option for preview files and smart rendering.

[Ivan Radovanovic]

[Ivan Myles] “Ivan, were all the luma values between 0-100 IRE?”

Yes. luma values are OK, problem is with DNxHD version. If you roll back to 2.2.1 (I think), the problem is gone.

https://twitter.com/#!/disample_dcc