How can I edit (cut) segments from a H264 AVCHD video without re-rendering?

[kmmoore]

OK,

I've been pulling my hair out these past few days trying to get this to work, and would appreciate any help you can offer.

I purchased an Hauppauge HD-PVR to backup my 1080i Sky recordings. This works extremely well, and the quality is excellent, however, I am having trouble finding a way to edit these recordings.

The HD-PVR records in .TS or .M2TS format in H264 AVCHD, and I want to simply cut out segments from the recording WITHOUT having to re-render the video. I can't believe this is turning out to be so difficult to do.

I have searched on here, spoken at length to Hauppauge tech support (who tell me that there is no way to do it), and tried various bits of software...Vegas 8, h264TSCutter, Premiere, amongst them, but although I can edit the files in various software packages, they all seem to want to re-render to save the edited video.

Is it possible to simply cut the video and save it ? Any thoughts ?

I did try one of the packages and allowed it to re-render the video. OK, it gave me the edited video I wanted, but there was a noticeable drop in quality, and that's what I want to avoid. Plus it was quite time consuming. Simply cutting the video file should (in theory) be virtually instantaneous.

One package that someone did mention that allowed (rudimentary) cutting was Imagemixer 3SE, but as far as I can see, that is a MAC only program, and I am running Windows XP.

Anyway, and help would be greatly appreciated.

Thanks,
Kevin.

[Hawkes]

I don't think I know of a way to edit a video without rendering it in some way, period. why don't you just like... set up your machine to render overnight, or something?

[kmmoore]

Thanks for the reply.

A couple of things.

Firstly, to be honest, it's not realy the time taken to render the file that's the problem, it's the quality degradation afterwards. If it did the job and the results were comparable, I would be happy to re-render the file, but the re-rendered file is much blockier then the original (if I keep the same bitrate).

Secondly, there are quite a few programs out there that simply cut video files without re-rendering them, but none of them handle M2TS files. Plus as I mentioned, Imagemixer 3SE (for the MAC) appears to be able to do this without re-rendering the video, so it can be done. I just need something I can use to do the job using Windows.

I'll keep looking, but any help would be great.

Thanks,
Kevin.

[Schmendrick]

h264TSCutter is not reencoding the cut videos! I already have used it successfully to edit H.264/AC3-satellite tv transmissions but I have no experience if it is able to properly cut Hauppauge HD-PVR recordings. These recordings as far as I know don`t contain IDR-frames just I-, P- and B-frames. On the Options- Settings - TS-Settings page of the programme you have to untick "CutOut only on IDR frame" and set Options - Settings - Advanced "CutIn frame type" to "I-Frame".

You should be aware that as you have to do the "Cut-in" on an I-frame to avoid distortions within the first frames you cannot cut a clip at fixed positions and thus either e.g. miss some frames or leave some preceeding frames within the cut clip.

Schmendrick

[kmmoore]

Ah, now I'm getting somewhere !!!

I did try H264TSCutter early on, but for some reason it doesn't like the M2TS files that the hauppauge produces, but it does appar to be able to handle the .TS files the Hauppauge can save in.

I finally managed to do some cutting with the file and although the interface is very basic, it does do the job, and for that I am very pleased.

I did as you suggest, and changed the settings to Cut-In at an I frame, but left the Cut-Out at all frames. Should I change the Cut-out frame to anything in particular or is all frames OK?

Also, when cutting, does H264TSCutter find the nearest I Frame and cut from there, or am I supposed to make sure I do the cut at an I Frame ? There does appear to be (for a fraction of a second) some video distortion, which I take is down to not cutting (in/out) at a correct frame type.

Any advice on how to remove or reduce this problem?

Overall though, despite its basic appearance, it does more or less exactly what I wanted it to do, so thank you very much for your help. Much appreciated.

Kevin.

[Schmendrick]

May be the following links are interesting for you.
First on link explaining a method for about just what you are interested in:

http://forum.doom9.org/showthread.php?t=142026&highlight=HD-PVR&page=3

and a link to a report of an other Hauppauge HD-PVR-owner and how he is using it:

http://blog.arogan.com/2008/06/hauppauge-hd-pvr-model-1212.html

I hope this will help you further.

Good luck!

Schmendrick