Commercials letter boxing on local comcast spot

[Jeff Meyer]

What specs are you using for your export?

If you’re delivering over Ad Delivery Lite they have specific specs they’re looking for — it is incumbent upon the user to deliver properly. They provide preview tools after the upload so you can see the results after it goes through their black box transcode. I’ve linked to the specs below.

https://www.comcastspotlight.com/userfiles/ComcastAdDeliveryLiteFileFormatSpecifications–100511.pdf

[Tim Johnson]

I have tried to follow their specs exactly.

I have posted the problem here. The first two images are simulated in photoshop. Then the report I got from Comcast about the file I uploaded. Then are screen shots of my export setting in premiere. It took three screen shots to cover all of the settings.

Thank you for looking.

https://tjtexas.com/problem

[Ivan Myles]

The issue appears to be related to the aspect ratio. Have you tried exporting with square pixels instead if Widescreen 16:9 (1.000)?

[Jeff Meyer]

Use DNxHD or ProRes. Comcast will encode those in their very particular preferred mpeg format. Don’t worry about the extra generation..Both of those codecs will deliver more detail than the final result will offer.

[Tim Johnson]

This is the one currently running (the problem)

https://docs.google.com/file/d/0Bw-mdk9MjOlGQjRMcFhxX0dod2M/edit?usp=sharing

and I just made this one using Square pixels (another source made that suggestion earlier

https://docs.google.com/file/d/0Bw-mdk9MjOlGbW9PSnpmWlFGWUE/edit?usp=sharing

I have not had a chance to upload it to Comcast yet. I can’t see any difference at all.

[Ivan Myles]

[Jeff Meyer] “Use DNxHD or ProRes.”

+1

[Tim Johnson] “I have tried to follow their specs exactly.”

I don’t think it’s related to the letterboxing issue, but the GOP structure in your export settings is different from the linked spec.

[Brian Mulligan]

a few things…
Comcast requires that all HD spots be center cut safe. Your spot does not look like it is.
Therefore, they may be downconverting it to SD Letterbox. Then it depends on the channel you are watching it on.

Are you watching an HD channel in HD? is your TV set to normal or stretch? Are you seeing this on an SD channel that is set to stretch?

Too many variables.

Brian Mulligan
Senior Editor – Autodesk Smoke
WTHR-TV Indianapolis,IN, USA
Twitter: @bkmeditor

[Jeff Meyer]

All good points — but the return email from Comcast with their encoded proxy and final output should give conclusive evidence of how it will play out of their spot server. Checking the proxy is a good delivery practice.

Letterboxing due to lack of center-punch-safe graphics is an interesting theory, but I sincerely hope their engineers wouldn’t introduce such an aspect ratio distortion. I’ve had their engineers call over issues before (they called minutes after I uploaded XDCAM 35 intended for a different network) and they seemed knowledgable enough and concerned enough to not do this to my client’s content. It could be policy to letterbox content that isn’t 4×3 safe, but that would be rather obnoxious.

My best advice is to use the Contact option after you login and get in touch with an engineer who can give you a conclusive answer.

For reference, I found their Premiere Pro/Adobe Media Encoder guide.
https://login.comcastaddeliverylite.com/Documentation/Lite/Media_Creation_Guide_AdobePremiere_Mpeg2_SD_HD.pdf

[Mark Thompson]

Hi, did you get a successful resolution to this?

nark

[Tim Johnson]

Comcast was automatically black boxing HD video to run on their SD channels. Trying an SD version fixed the problem, but then the reverse problem happened when they run that one on HD channels.

They should just center cut the HD version automatically…….. maybe someday such wild technology might be available.