Rendering problem, artifacts are ruining my life

[Joseph Owens]

[Alessio Romano] “as soon as i upload it to youtube or vimeo crazy artifacts appear”

Mostly macroblocking and 8-bit banding as far as I can tell, which is sort of normal-ish if the bitrate and sample-depth is not controlled very deliberately. Probably worse with ProRes, since both services will really hammer the file down to make it compatible with a bitrate the internet can handle.

Are you using a compression application like Apple Compressor or Adobe Media Encoder? They do come with some presets for net distribution that should help.

jPo

“I always pass on free advice — its never of any use to me” Oscar Wilde.

[Alessio Romano]

Hey Joseph,

Thanks for taking the time!

I did try to use compressor outputting media for streaming but it turned out even worse… anything i should/could do from Da Vinci?

Cheers

Alessio

[Marc Wielage]

I’m seeing a weird double image (chroma only) on the far right side. I’m assuming that shouldn’t be there.

I wonder if something is not being converted correctly in the transcode. What format are you shooting in? What format are you editing and color-correcting in?

The last 5D project I did, I had them transcode everything to ProRes 422HQ (and the HQ really wasn’t necessary, but I figured what the hell), and it came out surprisingly well, even on a 20′ screen. I think one key going in is knowing that the material is only 8-bit and you can only push it so hard. I kept the blacks on the somewhat-crushed side and also used a lot of vignettes in certain scenes.

The grayscale macroblocking is one of those 8-bit things you can’t overcome. As a last gasp, you could try to overlay some film grain on top of it and see if artificial dither reduces the stepping. These 8-bit cameras are really awful to deal with in situations like this.

BTW, you should definitely fix the audio — the singer is way, way off mic and too echoey (in my opinion).

[Alessio Romano]

Thanks man.

It was shoot with a 6D all-I H264
The audio you hear is from the camera, on the full video you can hear the real audio :).
I even tried crushing the blacks more but still… its unwatchable..
what is very mysterious to me is: How does it actually happen?
Because the playback from quicktime is perfect, looks real good.
Once i upload it all goes to hell..
I was Grading in Da Vinci and didn’t really do anything extreme, exported in h264 and also pro res but i pretty much get the same result once i upload.. what else could i try?

Thank you

[Marc Wielage]

Upload it to Vimeo and see if that looks any better. These gradiated shadows are a worst-case scenario for compression, because it’ll tend to exaggerate the 8-bit stepping. Not enough bits.

There are tutorials out there on the web that will explain how to optimize your material for upload to YouTube and Vimeo with the fewest possible artifacts. I generally work in ProRes 444 and post a ProRes 422 to Vimeo and let them handle the conversion within the site, and the results are acceptable to me when starting out with 10-bit material.