h264 export adds noise if not fullHD

Just reproduced/ran into the "color noise via export" bug whenever exporting to h264 from either 10.3 or compressor (also occurs with settings like "computer", "apple devices" and such - any h264 component). This should be a completely black slate, it's a gap actually but comes out very noisy (gamma lifted for better visibility). Something is broken in Apple's codecs!
P.S. only happens if NOT exported in 1920x1080 (share menu) and many others have run into that issue as well. can anyone provide any insight?

Is your original project 1920x1080? I'm wondering if the issue isn't resolution-dependent, but happens only if the image size is scaled during encoding. Maybe you could export a ProRes 4444 at a different size, compress that (without changing the size) and see if the noise is still there.

Also I'm kinda blown away that the noise is as fine as it is post-compression. Usually stuff like that falls apart when compressed.

yes project is 1920x1080 and noise is added whenever scaled down in the h264 export. the noise is definitely added during compression whenever scaling is taking place.

Yes, but what I'm wondering is if the noise is added when the image is scaled, period. If you were doing a 4K project and scaled down to 1080p on export, would the noise not be there just because it is now 1080p, or would it be there because the noise gets applied when you scale from any resolution to any other?

"… 'Doesn't work' is no error description"

actually tested it with a piece of black video (=scopes flat) and a black generator:
1080 project, exported with some custom 480/single-pass/h.264 setting = as black as posssible (brainfree to post a black rectangle :lol: )

sooo, specs of your media (scopes?) and specs of your export-settings …?

like many others have confirmed for me, it occurs whenever down-scaling takes place. so yes, if i have a 4K project and export in 1920x1080 it adds noise. i'm talking about the built-in h264 master file or any of the "apple devices", "computer" or "web streaming" presets. also compressor does it, that's why i reverted to v4.2.3 - no added noise there!

Tested exporting a gap clip out of a 1080p timeline to H264. Error is confirmed.

I've reported to Apple a week back and then sent them a load of stuff they asked for. I've not upgraded to 10.3 yet, but I was getting it in Compressor 4.3. As others have mentioned, my tests seem to conclude it is when scaling is involved. However, I get it in other codecs not just the H.264 exports such as a DVD I tried to export using built in Compressor DVD preset.

FWIW, I tested exporting a gap clip (from a 4K project) H264, 1080p. Pure black, no problem here.

I have the same problem exporting 1080p h264 from a 3200x1800 project. Even the black widescreen bars have this noise.

Let's get some specs guys, could it be hardware related?

I was able to reproduce the issue on FCPX 10.3, OSX 10.11.6, pro video formats 2.0.5.0 and a 2014 mac mini 2.8 GHz Intel Core i5, 8GB RAM, Intel Iris 1536 MB graphics.

both 1080 projects exported at 720, and 4k projects exported at 1080 exhibit the issue

Some further testing shows that the issue happens only under 8% brightness, and the noise is static (doesn't change over time), rendering this a non issue for me, as 1; it's practically invisible on a properly calibrated screen, and I would never have noticed it if not for this thread, 2; in a moving video the noise will be practically obliterated by the compression, and 3; I'm not going to be color grading scaled exports.

Also, to those that aren't seeing it, check in the scopes for a fuzzy line, and/or increase the highlights/gamma on the exported clip to make sure it isn't just invisible on your current display.

I've made some tests and It's worse than I thought. It happens with any codec different to ProRes, even with the uncompressed ones. It's like a static fix pattern that affects not only the black video but the entire video. It happens any time you export to a different resolution than the one from the project (smaller or bigger).
You can download the test a made here: bit.ly/2g3ERCK

I'm having the same issue when exporting a 720p h.264 quicktime movie. My project was shot in 1080p and does not show the noise when exporting a master 1080p file. It's only when it is compressed. The issue appeared after the update to FCP 10.3.

I'm running a brand new iMac 5k Late 2015.

Hopefully, apple comes out with an update to fix this soon!

please keep submitting detailed feedback to apple.
apple cupertino got in touch with me and followed up on my bug report, they now about the issue and are working on a fix.

Where did you submit your feedback to apple? On the Final Cut support forum?

the standard way to do it is by going to file->submit feedback within fcpX

Pick your product...
www.apple.com/feedback/

Or go direct...
www.apple.com/feedback/finalcutpro.html