Re-editing an exported video

[Angelo Lorenzo]

Well, what is the format you’ve been given? What is visually wrong with it? Your opening post is too vague really.

Are we talking about some really compressed web format like h.264 or some older interlaced footage? or?

Also, the best thing to do is be honest with the client. If they’re under a time constraint, they’ll have to live with the lesser quality and if they have the budget or opportunity they can pay you to recut now, and then reassemble the cut from the master footage later.

Angelo Lorenzo
Fallen Empire – Digital Production Services

[Jonnie Lewis]

Hi Angelo,

Apologies, I thought I’d been quite clear.

Basically they have given me an edited video in the format of a H.264 .mov.

When I place that into Premiere, there are all kinds of artifacts – quite hard to describe, but like large blocks of pixels and warping.

It plays and looks fine outside of Premiere, so it must be something Premiere is doing to it.

Any ideas if there’s anything I can do?

Many thanks in advance.

[Angelo Lorenzo]

It’s most likely Premiere. What version do you have? And what is your playback quality set to? It may be the Mercury Engine doing something funky.

Actually, it may be worth skipping this troubleshooting. Grab Avid’s codec pack https://avid.force.com/pkb/articles/en_US/Download/en423319 and try re-encoding to Avid DNxHD. As a warning it only supports sizes up to 1920×1080 so no 2k or 4k work.

In Adobe Media Encoder, choose MOV as your container, choose Avid DNxHD as your codec, click options and select 709, No Alpha, and any quality setting that says 185 10bit (ignore all the formats, these are guidelines and quicktime will ignore them), set your frame rate, dimensions, and pixel aspect ratio as needed and select uncompressed audio. Render it out and bring it back into Premiere. Using an intermediate format like DNxHD will give you some headroom for noise reduction and so forth.

Give one file a try and see how it performs for you and see if any of the green artifacts transfer over so you can eliminate it being a corruption issue or playback issue.

Angelo Lorenzo
Fallen Empire – Digital Production Services

[Jonnie Lewis]

I’m currently trying things out with CS5, but I’ll be using CS6 at work.

I downloaded that codec pack, and re-encoded the video. When you said “pick MOV as your container”, I picked QuickTime from the Format drop down menu – is that what you meant?

Anyway I did that, and threw it back into Premiere when it was done. I didn’t see any of the horrible artifacts I was seeing before, though it’s 3 times the size of the original file and is a bit jerky/jumpy when being played in Premiere’s source window, although it plays fine when it has been rendered in a sequence.

There is also some letterboxing which I don’t quite understand, as I set the dimensions to be the same as the source file, and the re-encoded file is about 3 times the size as well..!

Does that help shed any more light?

Thanks again Angelo.

[Angelo Lorenzo]

To answer your issues in order:

– Yes, Quicktime as a “format” is what you choose. It’s just more commonly referred to a container or container format because, well, it contains audio and video info.

– DNxHD is an intermediate codec, it trades quality and performance for file size. As to why it skips, your system may be under powered (my guess considering how Premiere reacts to H.264) or are you editing off of something slow like a USB external drive? If it works when the timeline is rendered, great; it’ll probably perform better on CS6. For all intent and purpose DNxHD will give you better editing performance with either program in comparison to H.264.

– I’m not sure why you’re experiencing letterboxing. Check your encoding settings again, especially the pixel aspect ratio. If it’s HD footage, you should strictly be working with square(aka 1:1 or 1.0). Also, when ingested back into Premiere, double check the sequence settings as well if you see issues in Quicktime, but it looks fine in Premiere.

Angelo Lorenzo
Fallen Empire – Digital Production Services

[Jonnie Lewis]

Thanks again.

In Media Encoder, I set the pixel aspect ratio to square pixels (1.0) and I matched all the export settings to be identical to the original file (frame rate – 25fps, dimensions – 1440×1080, progressive) and tried again. This resulted in no letterboxing in QuickTime and it looks the same as the original file – great.

However when I put it into Premiere it seems to be 4:3. Comparing the original file to my freshly exported file in the Project panel, the original says 1440×1080 (1.333) and the new file says 1440×1080 (1.0).

If I use Media Encoder to export a 1440×1080 1.333 file, the result comes out with huge letterboxes down each side.

I’m really confused now. If I set Premiere’s sequence settings to be 1440×1080, everything looks 4:3, but when I play the original 1440×1080 file, it looks 16:9?

Many thanks again.

[Jonnie Lewis]

If it helps, here is what Premiere says about each clip.

The original clip:

The re-exported clip:

Identical, yet Premiere seems to show one at 16:9, and one at 4:3?

[Jonnie Lewis]

Okay, I’ve just discovered that when the original footage is put into Premiere and rendered in the main timeline, it plays fine. No ugly distortion/pixels/warping – so that should hopefully save me from having to convert all the original files.

What confuses me now is… the original footage dimensions are 1440×1080, and when I put that into a 1920×1080 sequence it fits fine.

But when I export it as 1440×1080 it comes out as 4:3, and when I export it as 1920×1080 there is some letterboxing (top and bottom).

If I set the sequence up to be 1440×1080, it’s also 4:3. I don’t understand how the original footage can possibly be 1440×1080 yet it fits into a 1920×1080 sequence and appears to be 16:9 when playing with QuickTime?

Thanks a lot again!

[Angelo Lorenzo]

Jonnie, I made some assumptions when giving you advice. I wrongly assumed you were given something that was already converted for normal viewing, which would be 1920×1080 square pixel. It looks like, however you’ve been given some assembly cut that isn’t ready for prime time.

If this footage was given to you at 1440×1080 with a pixel aspect ratio of 1.33 then it needs to be rendered into DNxHD exactly like that and worked in that format; this format is common from some HD cameras as it’s a way to cheat not having a full HD sensor. When you give the footage to your client, you need to export to 1920×1080 square pixel, removing the artificial stretch, this will make it ready for normal viewing.

Angelo Lorenzo
Fallen Empire – Digital Production Services

[Bala Chandran]

When you bring in the rendered 16×9 file PPro is misinterpreting it. In the project window right click (MS Windows) on the footage and MODIFY> CONFIRM TO and select 16×9. See if that fixes the issue. 1440×1080 is DHV, not full HD. It just expands the pixel sideways to fit in a 16×9 format. Hope that helps.