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View Full Version : Vegas Pro 10 exceeding specified bitrate when rendering to MPEG-2


DanielG
2010-12-09, 09:25 AM
I have a project that runs for 101 minutes that I'm encoding to DVD but I'm having issues with Vegas Pro 10 adhering to the specified bitrates in CBR or VBR mode. Every encode I've done so far results in bitrates significantly higher than expected and therefore the finished file is too big for DVD.

Here are the results of my latest test.
Length of footage: 101 minutes
Bitrate: 5600 kbps (constant bitrate)
Audio: 384 kbps (mp2)

According to a bitrate calculator the resulting file should be 4,650,435,400 bytes (this is only approximate) but the actual file size is 5,096,998,912 bytes.

When I run the encoded file through a bitrate viewer (included in DVD-Lab Pro) the average bitrate reported is around 6500 kbps and sometimes spikes at 8000 kbps.

I have also tried encoding using VBR with the same issues.

lpmaskman
2010-12-09, 10:22 AM
Render to DV-Avi and then convert to MPEG2 with TMPGEnc Xpress, you can precisely set the bitrate.

DanielG
2010-12-09, 11:24 AM
Vegas 10 Pro allows you to specify the bitrate. You can specify a CBR or if you use VBR you can specify the min, average and max. The problem is that Vegas doesn't keep to these figures...:hmm:
Here are the render settings: http://i.imgur.com/SVDCa.jpg

xjsb125
2010-12-10, 12:55 PM
Frameserve it out to a different encoder like HC23. MainConcept is handy, but there are encoders out there that you will get better results from.

DanielG
2010-12-11, 11:02 AM
Thanks for the frameserving suggestion. I downloaded an open-source frameserver called "Debugmode Frameserver (http://www.debugmode.com/frameserver/)" which allowed me to pipe the encoding into TMPGEnc 4.0 Xpress. Though I needed to perform a minor hack to get DebugMode Frameserver working with Vegas 10 Pro (details are here (http://groups.google.com/group/frameserver-discuss/browse_thread/thread/66433d0fb929f38b) - see second post).

I'm not familiar with the HC23 encoder and I couldn't find anything about it online. Did you mean HC Encoder v0.25?

I do have a question about DebugMode Frameserver. When I save the signpost file, there's an option to specify the video output. The choices are: RGB24 (default choice) RGB32 and YUY2. Which one should I select? My source video is AVCHD 24Mbps from a Sony XR150 video camera.

Anyway, thanks for the help. I was pulling my hair out trying to get this encoding to work... It's strange that I wasn't able to find any other reports online re: the Mainconcept Encoder issues though...

xjsb125
2010-12-12, 02:40 AM
Debug Frameserver is what I use. As far as the HC Encoder, 23 is the build I have. I guess I should grab the newest one. I always leave the default RGB24. Anyone else is welcome to jump in with suggestions. As far as the Main Concept issue, failing to maintain the bitrates, I'm not sure why that is happening. I always had good luck out of it in the past, but I like HC better. Glad that the frameserving option helped out!

sysoverload
2010-12-12, 03:29 AM
you could render to an uncompressed avi with Vegas, then encode the avi with xpress 4.0. obviously you would need a LOT of free space.