Scene Dedection Fails with new HDR-HC1 HDV

Wes C. Attle wrote on 7/8/2005, 10:47 AM

Just got my HDV HDR-HC1 this week. Every time I capture with Vegas 6 or Cineform HD Connect, the scenes all get captured into one giant clip. I generally record many many 10 to 30 second clips on each tape with my cams, so I need scene detection during capture. Never have this problem with my DV cam, only this new HDV cam.

I noticed the only separate clips which I do get during capture correlate to each time I turned the camera off between recordings. Simply pressing the Record button to stop and start the record will not register different scenes in the HDV media which Vegas can read.

Just to be clear. When I capture 20 clips from my new HDV cam, Vegas and Cineform capture utilities do not compute the 20 clips. Instead, they just capture one big clip made up of the 20 clips.

Have I done something wrong, or missed a setting change in Vegas (or CineForm standalone HD Link utility)?? I noticed other users of FX1 and other HDV cams reported some poor scene detection, in my case it is 100% no scene detection, unless the cam was shut off between scenes.

The giant captured clips are showing the correct format and frame rate, so the camera settings do not appear to be the issue.

Any ideas?

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Comments

Wolfgang S. wrote on 7/10/2005, 9:07 AM

Xander: just as hint - a new version of AV-Cutty, that will be able to preview Cineform material as 16:9, is in the pipeline. Will be released by Andreas sometime in the future - at the moment the material is shown as 4:3, as you will know.

The disadvantage of that workflow is, that you work at least with the second render generation of Cineform Intermediates. As said, render tests are in the pipeline too, that will quantify this quality loss.

If you wish to avoid that, you could stick to the export of an edl list from AV-Cutty. The disadvantage is, that you cannot bring back that clips in the bin-structure again, since an edl import in Vegas does only work in the timeline.

Wolfgang S. wrote on 7/10/2005, 9:11 AM

"Related to this - the Maccites on various forums are going on about how FCP edits native HDV without the need for intermediate codecs. How true is this, and if so what equivalent PC would be able to perform this way?"

Peter, you can render native HDV if you work with Gearshift and proxys - and use the proxys to edit the material.

For real time preview of native m2t you will need much higher PC performance - I think SPOT had here a report about a 4-core PC. I assume that with that pc you should be able to have full preview capabilities also for m2t material - but I do not know how many native m2t steams you can preview until the preview capabilities drop down.

Xander wrote on 7/10/2005, 3:52 PM

Wolfgang S, I didn't think that av-cutty re-rendered the avi. I thought it just chopped it up like with DV. Am I wrong?

PeterWright wrote on 7/10/2005, 5:52 PM

> "Peter, you can render native HDV if you work with Gearshift and proxys - and use the proxys to edit the material."

Yes, Wolfgang, I've been doing that for months - I was just getting p'd off at the Mac sneerers saying "we don't need proxies" and wanted to check if they were bluffing!

I'm still looking for a faster proxy creation method, preferably with Gearshift - a 56 min widescreen DV avi took 11 hours last week! (I slept for most of that time!)

I must investigate your MJPEG codec - can you swap back and forth to HDV as per Gearshift?

Wolfgang S. wrote on 7/11/2005, 2:09 AM

Peter, to be able to swap back and roth mjpeg-avi files with m2t files, all what you have to do is to generate a new template. Name this template "HDV_", for example "HDV 1080i proxy MJPEG". Based on the string "HDV" + "<space>" Gearshift will list the template in the proxy media list.

To minimize both rendering time and hard disk space, the template could have lower resolution and poorer quality - and should not take 11.8 realtime for render. And the templates could look similar to what I have shown here:

http://videotreffpunkt.com/tutorials/HD%20Gearshift/HD%20Gear-47.gif

http://videotreffpunkt.com/tutorials/HD%20Gearshift/HD%20Gear-46.gif

resulting in following properties of the proxys:

http://videotreffpunkt.com/tutorials/HD%20Gearshift/HD%20Gear-45.gif

and change after the swap to the mjpeg-avis with following project settings (for PAL - for NTSC change the frame rate to 30 fps):
http://videotreffpunkt.com/tutorials/HD%20Gearshift/HD%20Gear-48.gif

You could also align the field order to progressive, if you wish to do so.

After you have switched back to m2t files, do not forget to change the project settings back to HDV 1080i.

@ AV-Cutty: yes, for DV-avi AV-Cutty does not render the material again when playing out separated files for each scene. I assume that it should be the same for Cineform files, but I am not quite sure about that. I will ask tht Andreas and come back to you.

PeterWright wrote on 7/11/2005, 3:12 AM

Wolfgang, you're a champion - thank you so much for all those screen shots.

As several have said, it's early days and we're all learning fast - for instance I haven't been changing the HDV project properties to DV Widescreen, resulting in jaggy edges unless preview is set to best - your post set this right - so simple, change properties to suit the proxies till it comes to render time.

Now - I must go back to your earlier post and find out where to get that mjpeg codec.

Thanks again.

Peter

Wolfgang S. wrote on 7/11/2005, 4:41 AM

Try this one here:

http://www.pegasusimaging.com/picvideomjpeg.htm

Costs something about 28$ for non-commercial use. A trial version is available with a watermark, as far as I remember.

Other mjpeg-avi codecs are available from Mainconcept or Morgan.

And yes, the main advantage of mjpeg-avi proxys is to get the pixel aspect ratio right - what cannot be achieved with DV-widescreen proxys really. Effects like PiP will suffer by that.

The full tutorial - where I took the screenshoots from - is available here (unfortunatly they are in German, but maybe the screenshoots are helfpul too):
http://www.videotreffpunkt.com/thread.php?threadid=1141&boardid=36&styleid=6

Wolfgang S. wrote on 7/11/2005, 7:14 AM

@ xander,

Andreas, developer of AV-Cutty, has confirmed some minutes ago, that AV-Cutty does not render a Cineform stream new. The material is only copied, as it is also true for DV-avi. That is independent from the codec.

So, the good news are that scene separation based on AV-Cutty will not add another render generation.