I'm going over some workflow options (24p for someone who cant wait for the FCP upgrade and 30p for someone else who has broken timecode that won't capture native) and have run into some snags with the whole transcoding scenario.

The m2t capture is no problem on HDVxDV or DVHSCap, even of whole tapes, but I am loosing sync on the HDVxDV transcodes on takes over about 5 mins (a 25 min clip is a few seconds out at the end).

I thought this was simply due to the fact that HDVxDV transcodes were incorrectly timed at 24 fps rather than 23.98 and I was happy to be able to try Nate's MPEG Streamclip demux method.
I've found though if you demux the m2t to separate m2v and aiffs, then RELOAD those into MPEGSTREAMCLIP, a resulting transcode to DVCPRO HD will be timed at 23.98.

That's a pretty cool trick, Nate – how in the world did you figure that out? Unfortunately, when I tried this (merging the transcoded clip from the demuxed m2v with the aiff file in FCP, after resetting the video speed back to 23.98 in Cinema Tools) it drifted out of sync as well, but in the other direction.

So at present, I'm not having luck with the transcoding approach. And the capture card method is going to give me 60p, which takes up a lot more room and there is no easy way to remove the pulldown. Any one having success with either of these methods on FCP?

Hi Andrew.

Recently I had the same experience, I found out that if I moved the InPoint in HDVxDV a few seconds ahead to trim the beginning, and then exported, the sound is back in sync.
Hope it works for you.

Very interesting Paolo. I will try it. Thanks.

Take your m2t file captured from HDVXDV and then
bring it into Streamclip. Use the "Fix Timecode Breaks"
option. Then, use the convert to Quicktime options.
pick Apple Intermediate Codec, deselect interlacing boxes
and select 1280x720 (HDTV).

You can then bring the files into FCP.
Make sure your FCP's video sequence preset is modifided to
Apple Intermediate Codec, HDV 24p settings you have to create.

Thank God Streamclip has a fix timecode breaks option.

Take your m2t file captured from HDVXDV and then
bring it into Streamclip. Use the "Fix Timecode Breaks"
option. Then, use the convert to Quicktime options.
pick Apple Intermediate Codec, deselect interlacing boxes
and select 1280x720 (HDTV).

You can then bring the files into FCP.
Make sure your FCP's video sequence preset is modified to
Apple Intermediate Codec, HDV 24p settings you have to create.

Thank God Streamclip has a fix timecode breaks option.

Hi Rob,

Thanks for the reply.

When I use this approach I get clips that have 24p inside a 60p stream, which is not what I want becuase of the space requirements and the difficulty of removing pulldown. Have you been able to use this method to get 24fps clips with no sync drift?

Yes, method works great.

My suggested approach was aided by Nate Waver.
I see Nate is constantly bombarded with the same topic
over and over on this discussion board.

A ~60 minute m2t file is about 8 gigs. Then
converted into AIC 720 24p (HDTV) Quicktime
is about ~17 Gigs (depending on your original footage's audio settings)

We have smooth realtime editing using multicam FCP with 4 Cameras
with these AIC Converted Quicktimes on a G5.

I don't mess with Compressor or Cinema Tools. I just use HDVXDV and Streamclip to be able to edit this HDV footage in realtime.

I am inerested in finding some low cost HDV or HD decks that can take
and HDMI input and record with better color options then the HD100U
or BR-50U 4:2:0 low standard. But, hey if have you seen some of Nate Waver's footage?; the colors are fantastic! What is his trick? Would make a heck of a writeup in Videography Mag.

Yes, method works great.

Hmmm. Rob, how are you getting 24p clips rather than 24 in 60 with MPEG streamclip? Are you demuxing first as Nate has suggested, and if so is it holding sync over the length of the entire tape when rejoined with the audio? Or have you found another way to avoid the pulldown frames?

HDVxDV is the only way I have been able to get 24p in my transcodes without demuxing, but sync is a big issue. Havn't tried Paolo's method yet..

Thanks for the input.

I found out that if I moved the InPoint in HDVxDV a few seconds ahead to trim the beginning, and then exported, the sound is back in sync.
I tried your method, Paolo, but got the same out of sync results. Don't know why. I also tried exporting an AIFF file of the audio from the transcoded clip before changing the frame rate from 24 to 23.98 in CT, and then joining the two back together. The sync was better, but still unacceptable.

Don't know what gives...

I tried your method, Paolo, but got the same out of sync results. Don't know why. I also tried exporting an AIFF file of the audio from the transcoded clip before changing the frame rate from 24 to 23.98 in CT, and then joining the two back together. The sync was better, but still unacceptable.

If you play the original .m2t file with VLC or MPEG Streamclip are they out of sync?

If you play the original .m2t file with VLC or MPEG Streamclip are they out of sync?

Hi Paolo,

No. Sync is fine on the m2t files when played back on any of the above or HDVxDV. The loss of sync is happening in the transcoding process.

No. Sync is fine on the m2t files when played back on any of the above or HDVxDV. The loss of sync is happening in the transcoding process.

Hmmm. Any chance you can put a short clip somewhere where I can download it and try converting it?

You can email me using phciccone at gmail dot com

Thanks very much for the offer, Paolo. I'd welcome some help to figure out what is going on. The only problem is that a short clip isn't going to tell us too much - the drift only becomes obvious after about 8 minutes and that would be a pretty big clip to get to you. At the end of 25 minutes, which is the longest m2t capture I have done, it is about 1 second out. Of course, the m2t files have numerous camera start/stops in them. Maybe that is a factor, but I'm not sure why it should be. So are you able to transcode m2ts of this duration witout any drift?

Thanks very much for the offer, Paolo. I'd welcome some help to figure out what is going on. The only problem is that a short clip isn't going to tell us too much - the drift only becomes obvious after about 8 minutes and that would be a pretty big clip to get to you. At the end of 25 minutes, which is the longest m2t capture I have done, it is about 1 second out. Of course, the m2t files have numerous camera start/stops in them. Maybe that is a factor, but I'm not sure why it should be. So are you able to transcode m2ts of this duration witout any drift?

You're very welcome Andy, the least I can do for someone who helped us so much. I'm not sure what can be done but this is one of those things that is quite hard to fix "remotely" so I'd like to give it a try personally and poke around. I can download bit clips, a few hundred megabytes are not a problem. See if you can zip it and shrink it a little bit. Send me a URL via email and I'll try my best :)
I had similar problem with several clips for my Vodcast. The .m2t was fine but the transcoded file was 2 or 3 seconds off. My clips were probably 5-10 minute long.

Andrew, I was following this thread and was wondering if you or Paolo had anything new to report on your sync issues?

It might be worth duplicating one of the tapes and fed-Xing it to Paolo if you are still having no luck on your end.

Andrew, I was following this thread and was wondering if you or Paolo had anything new to report on your sync issues?

It might be worth duplicating one of the tapes and fed-Xing it to Paolo if you are still having no luck on your end.

Hey Daniel.

I didn't get any news from Andy over the weekend so the jury is still out. If the size of the files is not out of reach I have no problems in letting the download go all night.

Hi Paolo,

Sorry for the delay in replying to your generous offer. My ftp site has a 80Mb upload limit and at that size we won't see anything. The clips that show the problem all too well are in the 3 to 5 gig range, so an ftp solution is not going to work from my site. Any ideas? I will send you a disk by mail if there is no other way and you're really up for it. You're on the west coast, right?

Hi Paolo,
Sorry for the delay in replying to your generous offer. My ftp site has a 80Mb upload limit and at that size we won't see anything. The clips that show the problem all too well are in the 3 to 5 gig range, so an ftp solution is not going to work from my site. Any ideas? I will send you a disk by mail if there is no other way and you're really up for it. You're on the west coast, right?

Hey Andy.

No solutions for transfers of that kind. Yes, I live in California, if you want to mail a disc I'll send you my address via email. I can't promise I'll find a solution but I'll try my best :)

What ever came of this? I'm having the same problem... All is well in the raw m2t file but quicktime throws it out of sync.
-aj

What ever came of this? I'm having the same problem... All is well in the raw m2t file but quicktime throws it out of sync.
-aj
Hi Adam.
Nothing happened, I don't know if Andrew found a fix but in any case, have you tried to trim a few seconds at the beginning of the clip. Basically set the Inpoint in HDVxDV one or two seconds ahead and then export again.

Yeah, I'm trying all kinds of stuff, the support guy(s) at HDVxDV is helping me figure out how to get my footage to an editable state.

MPEG Streamclip just might save my backside.

-aj

I'm going over some workflow options (24p for someone who cant wait for the FCP upgrade and 30p for someone else who has broken timecode that won't capture native) and have run into some snags with the whole transcoding scenario.

Andrew, would you consider Avid Liquid 7.1 for $500? Their capture routine has no Presets. It figures out that the JVC does 29.97 or 59.94 and captures it to disk.

Now you set your Sequence to either 23.98 or 29.97. When a 59.94 clip is droped into a 23.98 Sequence, it's smart enough to SKIP the Repeat Frame Flags. Nothing gets "converted!"

On output, the Repeat Frames Flags are reused. Nothing gets "converted!"

Plus, given Smart GOPS, with cuts-only Sequences -- only 2 GOPS at a cut a re-coded. By the way, runs on an MBP under Bootcamp.

Andrew, would you consider Avid Liquid 7.1 for $500? Their capture routine has no Presets. It figures out that the JVC does 29.97 or 59.94 and captures it to disk.

Steve, at this point I'm so fed up with FCP that *I* would consider it. Do they have a Mac version?

Andrew, would you consider Avid Liquid 7.1 for $500? Their capture routine has no Presets. It figures out that the JVC does 29.97 or 59.94 and captures it to disk.

Now you set your Sequence to either 23.98 or 29.97. When a 59.94 clip is droped into a 23.98 Sequence, it's smart enough to SKIP the Repeat Frame Flags. Nothing gets "converted!"

On output, the Repeat Frames Flags are reused. Nothing gets "converted!"

Plus, given Smart GOPS, with cuts-only Sequences -- only 2 GOPS at a cut a re-coded. By the way, runs on an MBP under Bootcamp.

Hi Steve,

Sounds interesting. Is this a native HDV timeline - no transcoding? Same file size, etc. or have the pulldown frames that get dropped actually been created from the flags? Is it fully compatible with the Avid family of products? Thanks for the info.

Hi Paolo,

Sorry I dropped the ball on that file. I'll try to get back to it.

Andy

Hi Paolo,
Sorry I dropped the ball on that file. I'll try to get back to it.

Hey Andy, you're a busy man. I was just replying to the previous post :)

Hi Steve,

Sounds interesting. Is this a native HDV timeline - no transcoding? Same file size, etc. or have the pulldown frames that get dropped actually been created from the flags? Is it fully compatible with the Avid family of products? Thanks for the info.

Fully native! Let me check file sizes and report back.

No real Avid compatibility -- it's a complete standalone application like FCP or Premiere.

OK, I've finally had a chance to experiment with this issue some more and I have worked a few things out. Both MPEG streamclip and HDVxDV continue to make transcodes that have sync drift, but I have learned a thing or two by doing tests with 10, 15 and 25 minute captures that have a slate at each end.

HDVxDV:
-Most of the trouble I had with HDVxDV and 24p material is due to two things: 1) the fact that the program incorrectly times transcoded clips at 24fps rather than 23.98 fps; 2) it is important to place an in point a few secs in from the head of your m2t before doing your transcode (Thanks Paolo for that suggestion). If you just let if fly with no in point it can give you really screwy sync right off the bat. To get around the timing problem you have to do the following:

1-mark your in point and transcode your clip
2-open the transcoded clip in Quicktime player and export the audio as an aif file
3-open the picture clip in cinema tools and retime it to 23.98
4-import both the retimed clip and the aif file into FCP
5-merge the picture clip with the aif clip. Turn off the volume on Trancks 1& 2. Tracks 3 & 4 of the merged clip will have sync that is better than 1 & 2, but not perfect.

Given the supreme hassle of doing all this and the fact that of MPEG streamclip version 1.7 avoids all of this and works better, I can no longer recommend HDVxDV (though it is still fine for capturing the m2t files).

MPEG Streamclip:
-Version 1.7 is much improved in that you can transcode directly to a 23.98 file rather than a 59.95 file, so no transcoded pulldown frames. Setting an in point does not seem to be necessary either. However, using fix timecode breaks does not make all of your sync problems go away.

Both programs were often out by a frame or two at the head. Once put into good sync at the head, both programs were out two frames after 15 minutes on a single takes with no camera start/stops, and 3 frames in a 10 minute clip with multiple stop/starts. When 25 minutes with many start/stops was transcoded, MPEG streamclip was out 6 frames at the end and HDVxDV was out 8 frames (once synched at the head).

So, neither program really does the job right, but MPEG streamclip at least does a slightly less poor job in less steps. I know that all of this seems very arcane, but if your dealing with hours of sync 24p material, these issues are a real pain in the butt.

By the way Paolo, I never sent you a clip to try because it sounded like you were having the same issues. If you really are able to capture up to 30 minutes with either program and have no drift please let me know. Thanks!