Smart rendering of HDV not working

[John Miller]

Hello,

I have a 5 hour HDV file captured using Vegas 8.0b. I need to create a sub-clip that is about 40 minutes long.

I have dropped the file on the timeline, marked the region I want and then started to render it using the Mainconcept HDV template. There are no effects on the clip. Smart rendering is enabled in Preferences. I've even aligned the start of the region to an I-frame.

The problem: only the I-frames are showing "No Recompression Required" (I assume I-frames since it happens every 15 frames). All the other frames are being recompressed.

Consequently, it is going to take approx. 1h 50m to render.

Any ideas as to why recompression is occurring?

Thanks,

John.

[Douglas Spotted Eagle]

If you're seeing the "No Recompression" turn on/off, it's not recompressing the frames, it's merely refreshing occasionally. The "No Recompression" indicator doesn't stay on throughout the render.
No-recompression doesn't mean it's like DV and it's instant. There are still structures to build that take a little time.

[John Miller]

Thanks, Spot.

When I perform a similar task with other HDV files captured from the same camcorder with Vegas, the "No Recompression Required" remains permanently displayed.

If I take the portion of the original file that I have rendered as .m2t and put that on the timeline, it also shows the message permanently when I render a portion of it.

The only two differences between my large file and the others are i) the file size and ii) the large file was captured from a live feed whereas the others were captured from tape.

I'm going to investigate these today or tomorrow.

BTW, if you are wondering why I would have such a long recording, here's a low res. snippet of the subject matter I was trying to get:

http://www.enosoft.net/videos/Raccoon.wmv

[Douglas Spotted Eagle]

Fun bit of video!
I'm not seeing the No Recompression in 8b staying on the screen all the time, but I'm also not working with HDV at the moment. XDCAM HD and EX should behave the same as HDV tho... Now I'm curious, too.

[Paul Kellett]

I can't find "smart render" in my preferences.
And what exactly is smart render ?
And i don't see a sign for "No recrompression",where should that be ?
I'm using EX1 files.

Thanks.
Paul.

[Tom Roper]

Originally Posted by Paul Kellett

And what exactly is smart render ?

Smart render is editing in the native codec. For simple edits, cuts and splices, only a few frames around the edit point get rendered, saving lots of time and preserving the native quality without a generational loss.

But if you color correct, the whole clip gets rendered.

Smart rendering is smart!

[Paul Kellett]

I've just looked at my preferences again,i cannot find smart render.

[Mike Kujbida]

Options - Prefs - General.
It's the very last one: "Enable no-recompress long-GOP rendering".

From the Vegas online help menu:
Select this check box if you want to pass through unedited frames without recompression for the following formats:
DV AVI
DV MXF
IMX MXF (IMX 24p MXF is not supported for no-recompress rendering)
HD MXF
HDV
In order to perform rendering without recompression, the width, height, frame rate, field order, and bit rate of the source media, project settings, and rendering template must match.
Frames that have effects, compositing, or transitions applied will be rendered.

[John Miller]

Originally Posted by Douglas Spotted Eagle

Fun bit of video!
I'm not seeing the No Recompression in 8b staying on the screen all the time, but I'm also not working with HDV at the moment. XDCAM HD and EX should behave the same as HDV tho... Now I'm curious, too.

I ran a test last night comparing live vs. recorded capture. i.e., I captured a short clip (about 2 minutes) while recording to tape as well. I then captured the recorded clip. Not surprisingly, both clips behaved the same way when rendering just a small portion (the No Recompression Required remained on).

I'll test the file length next which might require a l-o-t of capturing.