Compressor: 30p to 29.97

Has anyone encountered any issues when compressing 30p to 29.97 using Compressor?

Are you doing a straight conversion or are you slowing it down to 29.97?



www.strypesinpost.com

Was told I could do a straight conversion using Compressor.

I would actually slow it down by 0.01%. This would ensure that you have the smoothest and highest possible resolution.

If you are working off a format like the Canon 5/7D, which shoots to H.264, you'd use Compressor. You'd pop in a 29.97 preset, and in the frame controls tab, check the "so source frames play at 29.97" option near the bottom.



www.strypesinpost.com

We need to clarify some things here.

In almost all cases, "30p" is synonymous with 29.97. One is just an abbreviation for the other. If that's your deal, then there's no converting to be done at all.

I said "almost all," though, because that damn Canon 5D Mk II messed everything up by outputting "30p" footage that is actually thirty frames per second. Not 29.97 as in the NTSC standard, but exactly 30. And suddenly everybody got confused and annoyed and frustrated about having to stop all the time and ask, "Wait, do you mean 30p like as in the decades-old NTSC standard that everybody on the planet understands even if they live in a PAL country, or do you mean 30p in the Canon sense of the word?"

So I have to ask: Do you mean 30p like as in the decades-old NTSC standard that everybody on the planet understands even if they live in a PAL country, or do you mean 30p in the Canon sense of the word?

Good point, Jeff. I'm assuming that because he mentioned 30 and 29.97, he's talking about the oddball full integer/old black and white tv frame rate (most likely from Canon).

Sheesh, you guys live in a crazy world there.



www.strypesinpost.com

Yeah, if we were betting I'd put my money on that assumption too, but ? well, I'm really bad at poker. So I figured it was worth asking.

And you're one to talk about living in a crazy world. At least our water spirals down the toilet the right way.

> At least our water spirals down the toilet the right way.

That's Nick's area. I'm 10 degrees north, so the toilets work fine.



www.strypesinpost.com

See how messed up the southern hemisphere is? Things that obviously should be in it, aren't!

"Terra australis incognita," indeed.

Actually Canon's specs on the HV40 say that it's truly 30p.

mo

That would stun me if it were true, since the HDV standard doesn't support that frame rate. Not that I'm too lazy to google it, but I'm far, far too lazy to google it. Got a link that clarifies that, perchance?

If you're talking HV20, I'm with Jeff... I think 30p is short for 29.97p (which looks like a mathematical equation). But you need to check the papers...

What happens if you pop the raw file into FCP? What frame rate does it mention? Also, what frame rate does QT player put it as?



www.strypesinpost.com

This is all theory - as I'm considering purchasing the camera and was asking question in advance. I appreciate your comments and believe you might be right about the 30p - 29.97. I'll do more research.

Thanks again, all of you.

Marcia

Yes- I've tried transcoding 1280x720 30p (jpeg) to 1280x720 (960x720) 29.97 (dvcprohd). Compressor will not change the non-drop frame footage to drop frame. That is, unless I'm doing something wrong- which is entirely possible. Final cut says the newly transcoded footage is 30p and not 29.97..

Actually, I'm transcoding to DVCPROHD 720p60 with a frame rate of 29.97 (960x720), as there is no option to go to DVCPROHD 720p30. I assume the former is the standard that DVCPROHD uses.

Those issues aside, compressor (although I'm telling it to transcode to a drop frame format) will not give me the frame rate I'm telling it to encode to; thus, I cannot edit multicam style in fcp5.

Any suggestions???

Thanks all,
Patrick

Well... I believe I've found the answer to my question by myself.. Doesn't that always feel better?

When trying to change the frame rate (at least in this situation), you must enable "frame controls." That is, set them to "custom." I didn't change any setting in that tab except for the "retiming control." I changed this setting to "fast- nearest frame."

Worked like a champ... 30fps to 29.97fps...

There you go... well, there I go...

Patrick

That's a weird workaround. Checking the "so source frames play at 29.97fps" option should work. How does the movement look after the reverse telecine?

Btw, I think you're confused by "drop frame" and "non drop frame" timecode. Drop frame timecode means that 2 frames numbers will be dropped every x number of minutes (pardon me, but I'm not in NTSC land, so I don't remember the exact duration), so the timecode doesn't gain or lose any stated duration when running against a real time clock.



www.strypesinpost.com

I tried transcoding the clip 13 different times before I tried working with the frame controls tab. In the info tab, compressor was saying it would encode the new vid at 29.97. 12 of 12 times this didn't work- that is, every time it produced a video with a framerate of 30p.

The "workaround" I used can be found on page 195 of the Compressor 2 manual; although it mentions nothing about the problem I encountered...

I could tell no difference between the old clip, and the newly transcoded clip. Although it wasn't quite as pretty as the video the hvx shot, it still worked fine. That is, there were no jitters, jutters, or studders.. (not like Reuben)

I believe I understand drop-frame and non-drop-frame timecode. It was the issue of making the framerate match for multicam editing that threw me off...

The "so source frames play at 29.97fps" can be found where?

Thank you,
Patrick

> Reverse Telecine: This option removes the extra fields added during the telecine
>process to convert the film?s 24 fps to NTSC?s 29.97 fps. Selecting this item disables
>all other items in the Frame Controls pane.

Is this what you're talking about? I don't have the Compressor 2 manual, but reverse telecine removes pulldown when you shoot in 24p or 24pA to bring you down to 24fps from 29.97.

The conform to codec frame rate option (not its real name), is at the bottom of the Frames Control tab, at least in Compressor 3.



www.strypesinpost.com