avchd in Vegas

[Jeff Harper]

I'm editing a single camera video from the HMC150, the files are awful to work with, very slow performance. this is consisent with my previous experience with the camera, a year ago when I owned it. (part of the reason I ditched it).

On the other hand, I can edit three cameras with raw files from the GH2, also avchd, with no problem. Anyone know why they handle differently?

Files are on the same drive, a 4 disc raid 0 array.

[David Stoneburner]

Is it a bitrate thing? What is the difference between the files? Maybe look at the difference of the bitrate of the audio too. That would be my guess if they are both the same codec.

[Jeff Harper]

thanks, checked the bit rates, and on one camera (GH1) the bit rates are actually quite high, but still play smoothly, like butter. The files fro m the hmc-150 are brutal. Good idea, but doesn't seem to be it, unless I'm missing something.

[Steve Game]

Jeff,

AVCHD is MPEG4, and as such, CODEC providers have a bunch of compression tools that they can use. In its simplest form, the video using the equivalent of MPEG2 compression in a MP4 wrapper is just technically compliant with the MPEG4 standard. The very best CODECs in either hardware or software use more of the MPEG4 compression toolkit, whereas lower cost products reduce the development and implementation hardware required by omitting some of the more complex features.
Whilst all compliant players, (hardware and software), can decompress all of the features, the processor load increases with the more complex compression method. Within reason, the data rate doesn't present much of an extra burden on the processor, but it does on the storage system.
It's quite possible that Panasonic use more of the complex tools on a dedicated camcorder like the HMC150 in order to give a better result than they do on what is a stills camera with a bolt-on video capability like the GH1.
My Canon 550D records MPEG4 video at a data rate of between 40 and 50Mb/s, and it's quite easy to handle on Vegas 10 compared with the 24Mb/s NX5 video. I deduce that Canon have cut a few corners on the 550D as it runs fairly smoothly on playback, but the compression is neither efficient nor of particularly high quality.

[Iker Riera]

which version of Vegas are you using?

i'm using Vegas 10 and i'm editing AVCHD files with no problems. Up until version 9 they were almost impossible to work with and i always had to transcode them to something like Avid DNxHD to be able to work with them. With version 10 i feel they run even smoother straight from the camera than the avid files.

[Jeff Harper]

Thanks Iker, I'll keep that in mind.