Problem transcoding from AVCHD to Pro Res 422

[David A. Goldenberg]

Just shot an event with new HXR-NX5U in the preset FX mode. I archived the original clips to a hard drive and then executed log and transfer in FCP 6. I had no problem with short clips (up to 4 mins.), but am having great difficulty capturing from a one hour plus single clip. I have tried transferring the entire clip and briefer portions. The transfer goes on for hours and then freezes.

I am using a MacPro 2 x 2.8 GHz Quad Core with 10 GB of memory and transferring to a hard drive with 300 GB of free space.

I originally tried to log and transfer directly from the FMU-128 with the same results.

Note that I archived to the same drive where I am trying to transfer.

Just joined this network and would appreciate any suggestions.

David

[Benny Ek]

If all else fails, try to convert the clips using Roxio's Toast 10
It has saved me once when Final cut would not transcode a certain clip.
not as automatic and seamless as FCP but it works in those situations.

[Scott Cassie]

Hi,

I just got the NX5 yday. Read your thread and decided to film a a clip for 30mins and try to take it in (using final cut pro 7). Same problem as yourself. Was taking ages, and didn't seem to be making progress beyond the half way mark on the progress bar. After 90mins I gave up.

Then decided to add an out point half way through, and try to capture the first 15mins. This did work, but took around 45mins (my mac pro usually transcodes avchd to pro res faster than realtime, and does so on the short clips I've shot with the nx5 thus far).

My guess is that it has something to do with the way the nx5 pieces clips together that are longer than the 4gb limit. My previous camera, hm151 had no problems importing 25-40mins clips at speed. And the same goes for my B cam, Canon hfs100.

So will either have to record wedding ceremonies in 10mins chunks, or divide it up at the log & transfer stage.

Scott

[David A. Goldenberg]

Scott,

Are you estimating the "4 GB limit" or is that from a tech. source? One major issue is that each clip is transcoded with a time code set to 00 so that linking clips from single event will present problems. I did try doing the same thing that you did, transcoding @ about 15 mins and that did not work for me. I don't know if the length of the original clip has any bearing; mine was 1 hour, 6 mins.

I also noted in the manual page 61 that one can "divide a movie" on the camera so that may be a workaround that assures continuity.

Hopefully, Apple will create an FCP adjustment that deals with this.

David

[Scott Cassie]

Hi David,

The 4gb limit is a guess, but thought that SD cards and the like are all based on the FAT32 file structure which caps at 4Gb, I could be wrong.

When working with other AVCHD cameras I've never has a problem with any length of clip, which made me wonder if it's something the Sony's do different, prob just a software kinda issue.

Will have a go at 'diving a movie' in camera to see if that helps, plus will try importing clips with an original length of around ten mins to see if they transcode fine (& in a reasonable amount of time).

Scott

[Scott Cassie]

Final cut users - don't use PCM audio, switch it to Dolby (in camera).

Here's my test results that prove it was the uncompressed PCM audio causing the long transcodes:

PCM - 4.42mins clip - 5mins to transcode
PCM - 9.04mins clip - a whopping 18.20mins transcode (the longer the clip, the longer than real time it takes to transcode!)

Dolby - 4.19mins clip - 1.04mins to transcode
Dolby - 9.12mins clip - 2.18mins to transcode

That's more like it, and what a relief I can tell you!

Scott

[David A. Goldenberg]

Scott,

Thanks. That's an important discovery despite the fact that PCM audio was one of the camera's selling points. I suppose that the only solution post-shot is to transfer in smaller, manageable clips. There's no way to transform the audio prior to transfer once it's been shot, right?

I'm surprised that this issue hasn't drawn greater attention given that the default setting is PCM audio.

David

[Benny Ek]

That's interesting.
I actually shot a project 2 weeks ago on my NX5U that required PCM Audio. I shot in 20 minute chunks, imported into Final cut pro and they transcoded without a hitch without long transcode times.
I wonder if it is a combination of PCM and another issue rather than an "all PCM Audio" issue.
I know it throws a wrench in the theory, but "works for me"

[David A. Goldenberg]

Benny,

While we continue to search for the solution to transcoding in FCP, I am following up on your suggestion to use Toast. First, I noticed that when I archived my 1hr 06 min clip to the hard drive, it was split into several MTS files with a max length of 11:54. Now when go to convert them, Toast offers me five Device File Format options: DV, HDV, H.264 player, Mpeg-4, and QT movie. Which do I select? I see that within each option, I can select Apple Pro Res 422 and audio options. Thanks for the support.

[Benny Ek]

QT---ProRes 422
you found it. works for this situation but I hope the solution for Final Cut is fixed for you.

[David A. Goldenberg]

Thanks. I've reset the camera to Dolby for now, but feel that there must be another solution given our experience with PCM.

[Adam Welz]

I've also noticed crazy long transcode times for long clips. I thought I was imagining things. I'm using FCP 7.01, recording PCM audio.

I really want to use PCM audio -- this is a real bummer -- who does one need to contact at Sony and/or Apple to get them to sort this out?

Cheers

Adam

[Dave Luda]

I've been trying to get this simple question answered a few times now, I will take a stab at it on this post.

Is Final Cut Pro log & transfer faster with version 7 (Studio 3) than version 6? I currently have FCP 6.0.6 (Academic) and the log & transfer times take as stated above 3x the length of the footage. this pretty much defeats the purpose of going tapeless since it now takes me longer to transfer footage than if I did a log & capture. Why won't apple just take AVCHD natively like just about everyone else (Premiere Pro, Vegas, heck even Pinnacle) And yes, I have the audio set to "dolby" and NOT "linearPCM". So that is not the issue.

I am really really really curious what version of FCP Scott Cassie is using!!! He keeps posting that the issue is the audio setting and yet everyone still has the same problem after switching to dolby.

As for contacting Sony, don't bother...it's a software issue with the NLE and Sony will just tell you that "they" the software developers need to revise their code.

thanks!

[Scott Cassie]

Hi,

I'm using Final Cut Pro 7, on Snow Leopard.

The type of computer you have plays a large part in the transcode times. I've been shooting AVCHD on final cut for over a year now.

- On my 2007 iMac it took longer than real-time.
- On my new MacBook Pro is takes longer than real-time.
- On my 2009 MacPro is takes quicker than realtime.

Not sure if it's the RAM or number of cores, or hard drive speed (imac & macpro have same speed hard drives). Strange as we know Final Cut can only use 3GB of ram, and doesn't take advantage of multiple cores, but this is my real world experience.

[Adam Welz]

Hi Scott

I've read that core number is important -- apparently a single core can only handle one AVCHD clip at a time, therefore the more cores, the more clips can be simultaneously transcoded.

How many cores does each of those macs have?

Are your timing estimates based on batches of clips, or comparisons of the time it takes to transcode single clips?

It seems to me that on my new dual-core MacBook Pro short clips go through in less than realtime, long clips longer than realtime.

Adam