QT quality question

[Ervin Farkas]

I am cooperating with a guy on producing a televised show. He records off of the video switcher using Adobe Premiere, does basic cutting, adding still, etc, and than hands he video over to me for audio work, lower thirds, credits, and so on. I take over the Premiere project brought to me on a USB hard drive and life is good, no quality or other issues.

Recently he recorded on location instead of the studio and used his MAC laptop running Final Cut. For whatever reason he decided to bring me the finished video in QT format (.mov) instead of .avi. It looked terrible! So next time he brought me a project, I asked him to bring me a short test video in both formats, exported from the same FC timeline.

See attached pictures. Both files played in the same player, MediaPlayer Classic on PC running XP. The QT codec is QT Alternative latest version, AVI is played by the supplied Microsoft codec.

Any ideas to clear up the mistery are begged for. Click on images for full 720x480 resolution. Disregard the interlace jaggies, I intentionally did not deinterlace.

[Daniel Ross]

From what I can tell, there are two problems:

1. codec
2. gamma


Though you say it's something else, that looks a lot like the way the DV codec is displayed. It's also the default for capturing on a Mac (FCP, iMovie, QT, etc.).

Whatever the codec, it seems it might just be unable to decompress it at the proper rate for playback and, really, it's just fine. But your computer won't display it. Export as uncompressed and see what happens.


Mac gamma is higher than PC gamma. That's just an annoying thing about transferring files.

However, it's also an easy fix. Use levels and drag the middle slider to .6 (rather than 1), and it should be right. Then again, if that is backwards, you'll need to slide it down. I'm not sure on that math. About 1.45? Something like that...

[Roy Colquitt]

Ervin,

I can confirm part of what Daniel was saying--that a QT DV file from FCP will not display properly in a Windows desktop player while there's nothing wrong with the file itself. While I don't know what the reason is, it doesn't make sense that it's any kind of rate issue because even a paused frame shows the distortions.

If you try the file in your NLE, I'm sure you'll find that there's nothing wrong with the quality. It will play out to a production monitor normally.

[Glenn Chan]

For DV files in Quicktime, you should enable high quality playback. In QT player (QT Pro), go
Crtl J
Video settings or video tab or something like that
click the "high quality" checkbox

2- There might also be gamma issues / inappropriate color management going on.

2b- There looks like a difference between studio RGB (16-235) levels and computer RGB (0-255) levels. The right still has black at about 16, whereas the left still has black close to 0.

[Daniel Ross]

Mac gamma is simply higher. This is a very well documented fact. PC gamma is lower. It's something you need to deal with, but not impossible.
Depending on the program, it may also simply change how it's displayed if it knows this.

Take a look here:
http://www.kenstone.net/fcp_homepage..._from_fcp.html
And here:
http://dvinfo.net/conf/archive/index.php/t-73197.html

//google search

[Ervin Farkas]

Originally Posted by Roy Colquitt

If you try the file in your NLE, I'm sure you'll find that there's nothing wrong with the quality. It will play out to a production monitor normally.

Unfortunately that is not the case - I imported the file in Premiere Pro and was able to tweak it a little, but it still looked very poor, sort of like a third generation VHS copy.

Fortunately that was a not very important shot and for the future my friend will stick with AVI.

[Ervin Farkas]

Originally Posted by Glenn Chan

... go Crtl J Video settings or video tab or something like that click the "high quality" checkbox...

I don't have QTPro, all I have is QT Alternative. But I don't see why a high quality DV file would need player adjustments when much lower QT files downloaded from the internet look a lot better.

[Roy Colquitt]

Originally Posted by Ervin Farkas

Unfortunately that is not the case - I imported the file in Premiere Pro and was able to tweak it a little, but it still looked very poor, sort of like a third generation VHS copy.

Fortunately that was a not very important shot and for the future my friend will stick with AVI.

I guess I overstated what was actually partly assumption. I should have said that I have Intel Macs with Bootcamp and I've found that while FCP exported DV QT files look pixelated in Windows QT player, they look and work just like DV AVI files in GV Edius. That certainly doesn't mean that the same is true of any other NLE.

But it looks like you have it solved by getting AVIs from now on.

[Daniel Ross]

Well, if it really is lower quality, you should put it back on the mac and re-export. That's all you can do.

[Glenn Chan]

But I don't see why a high quality DV file would need player adjustments when much lower QT files downloaded from the internet look a lot better.

That's what you have to do in Quicktime player (though this doesn't apply to other players). That's.... just what QT player does in my experience.

I don't know about Quicktime alternative.

[Andrew Kimery]

Have you looked at the properties of the QT movie? The guy just might have not put in the most optimal settings for export. I'm not familiar w/the "QT Alternative " codec but maybe it's not a very good codec?

Just to nitpick but "AVI" and "MOV" are just wrappers and have no inherent indication of the quality of the video file.


-A

[Ervin Farkas]

Originally Posted by Andrew Kimery

Have you looked at the properties of the QT movie?

That was also my first reaction, but he showed me both files on his Mac laptop, and both of them looked exactly the same, sharp, good colors. File sizes are the same, and when analyzed with G-Spot, both of them are around 25 MB/sec so that's correct.

[Daniel Ross]

Then it's the conversion on your system.
Just like the issues we've mentioned with the DV codec, it isn't processing it correctly.
If it is also not processing it correctly when exporting from your NLE, then that's clearly a problem, even maybe a bug.
If you can't find a workaround and it doesn't end up full quality once exported uncompressed, again, you will simply need to re-export.

From my experience, using QT on a Mac and AVI on a PC is the best way. Both as uncompressed play fine on both systems (almost all the time, anyway), but any codecs can cause weird problems. Mixing systems/formats ESPECIALLY with codecs is just asking for trouble. It *should* work, but if you don't know the workarounds (and it's a weird format, so no one here seems to have any idea what it is), it's not reliable.

[Ervin Farkas]

The problem has been basically solved from the very beginning, we now know that our cooperation doesn't work with QT files, so if he will ever bring me in the future video processed on his Mac, he will bring it in AVI format instead of QT.

I was just trying to understand why Adobe Premiere and my PCs in general have trouble interpreting that particular footage. I have, in the past, downloaded QT files off the internet, from iStock for example, and they look incredibely sharp and with wonderful colors. It might have been the particular settings or the particular codec he used to export from FCP.