"Video Buffer Underflows"

Jim Hall wrote on 9/16/2011, 10:59 AM
I generally have no problem burning Standard Def and Blu Ray DVDs with the DVD Architect. I have one particular Blu Ray project that I'm having problems with. When I try to "Make Blu Ray Disc", the program works for about an hour then stops and displays this message:

"File name: STREAM/00004.m2ts
Status: TSWrapper.dll::CTSWrapper::ProcThreadMain::Video buffer underflows. -"

I've checked a number of things in the way I have built this particular DVD project, but I just can't seem to figure out what's going wrong. Any ideas?

Comments

Steve Mann wrote on 9/16/2011, 2:25 PM
Please fill out your system Specs in the profile so we don't have too ask what you're running.

Buffer Underrun used to be quite common when writable CD's first appeared in the 1980's. The problem was that the CD writers were unbuffered (and very expensive at over $500 per), and the PC was not able to deliver the data to the CD burner fast enough. Faster PC's made this problem history. Then writable DVD's hit the mrket. Same problem, but not as bad since most DVD writers had some RAM buffer built into them.

When Buffer Underrun errors started showing up in Blu-Ray burns, I thought this was Deja-Vu all over again.

But, when someone pointed out that this occured when he was "preparing" the BD, not even going to the burner yet, I had to do more research. Here's what I found on other systems boards (it's not limited to Vegas or DVDA):

* An underflow (underrun is a better term, actually) is when the bit reservoir, i.e. the amount of bits available to encode with, isn't large enough to hold the encoded frame. Basically, if you want 6000 kbps then you're allowed 6,000,000 bits per second; if you've already used 5,999,000 bits and your next frame is larger than 1000 bits, then a strict hardware player won't be able to read the frame from disc in time--its playback buffer will become empty, hence a "buffer underrun".

* Your total combined (audio and video) bitrate is too high.

* Buffer underflow errors can also happen when the mpeg file was made with variable bitrate and no lower limit was set

Tell us what your encoding parameters are, and if you fix the problem, please tell us what you did.
PeterDuke wrote on 9/16/2011, 11:47 PM
Would two-pass encoding fix the problem?

Edit
One or two-pass, constant or variable bit rate for MPEG2. One pass constant bit rate only for AVC.
Steve Mann wrote on 9/19/2011, 4:15 PM
"Would two-pass encoding fix the problem?"

No. Two-pass only makes for more efficient encoding, but it doesn't change the overall bitrate.
Arthur.S wrote on 1/20/2013, 3:25 PM
Pity the topic starter didn't reply back - that's what a forum is for! I've run into this exact problem myself for the first time. I think it's because my MPEG2 files are encoded at the max of 9,800. I've set DVDA (5.2) to recompress at 9,000. We'll see if that works.
Arthur.S wrote on 1/21/2013, 5:38 AM
OK, it worked. Before I did that though, I re-installed DVDA 6 to see if this had been fixed as it's a well documented bug going back a long way. Not fixed. Even worse, DVDA 6 is slooooooooow in comparison with 5.2! Was showing almost 5hrs total time in comparison with 5.2's 3 1/2 hrs.