How do I know what bitrate my video is?

[nebbish_2112]

What is an accurate way to determine the bitrate of my existing .mpg video file? I am trying to author a DVD using GUI for dvdauthor and get an error "*ERROR: [???] MUX STATUS: Frame data under-runs detected!"

I don't know if this is because the video is encoded at too high a bitrate? Does the following log really mean my max bitrate is 14995600 bits/sec?


Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.


(shrink and) mux video and audio files
INFO: [???] mplex version 2.0.0 (2.2.3 $Date: 2004/01/13 20:45:26 $)
INFO: [???] File C:\Documents and Settings\jwebb\Desktop\1 Biology.demuxed.m2v looks like an MPEG Video stream.
INFO: [???] File C:\Documents and Settings\jwebb\Desktop\1 Biology T01 DELAY 0ms.mpa looks like an MPEG Audio stream.
INFO: [???] Video stream 0: profile 8 selected - ignoring non-standard options!
INFO: [???] Found 1 audio streams and 1 video streams
INFO: [???] Selecting dvdauthor DVD output profile
INFO: [???] Multiplexing video program stream!
INFO: [???] Scanning for header info: Video stream e0 (C:\Documents and Settings\jwebb\Desktop\1 Biology.demuxed.m2v)
INFO: [???] VIDEO STREAM: e0
INFO: [???] Frame width : 720
INFO: [???] Frame height : 576
INFO: [???] Aspect ratio : 16:9 display
INFO: [???] Picture rate : 25.000 frames/sec
INFO: [???] Bit rate : 15000000 bits/sec
INFO: [???] Vbv buffer size : 229376 bytes
INFO: [???] CSPF : 0
INFO: [???] Scanning for header info: Audio stream c0 (C:\Documents and Settings\jwebb\Desktop\1 Biology T01 DELAY 0ms.mpa)
INFO: [???] MPEG AUDIO STREAM: c0
INFO: [???] Audio version : 1.0
INFO: [???] Layer : 2
INFO: [???] CRC checksums : yes
INFO: [???] Bit rate : 24576 bytes/sec (192 kbit/sec)
INFO: [???] Frequency : 48000 Hz
INFO: [???] Mode : 0 stereo
INFO: [???] Mode extension : 0
INFO: [???] Copyright bit : 0 no copyright
INFO: [???] Original/Copy : 0 copy
INFO: [???] Emphasis : 0 none
INFO: [???] SYSTEMS/PROGRAM stream:
INFO: [???] rough-guess multiplexed stream data rate : 15509344
INFO: [???] target data-rate specified : 10080000
++ WARN: [???] Target data rate lower than computed requirement!
++ WARN: [???] N.b. a 20% or so discrepancy in variable bit-rate
++ WARN: [???] streams is common and harmless provided no time-outs will occur
INFO: [???] Run-in Sectors = 89 Video delay = 13019 Audio delay = 0
INFO: [???] New sequence commences...
INFO: [???] Video e0: buf= 237568 frame=000000 sector=00000000
INFO: [???] Audio c0: buf= 4096 frame=000000 sector=00000000
++ WARN: [???] Stream e0: data will arrive too late sent(SCR)=31158 required(DTS)=0
++ WARN: [???] Video e0: buf= 184455 frame=000005 sector=00000210
++ WARN: [???] Audio c0: buf= 4091 frame=000007 sector=00000002
INFO: [???] STREAM e0 completed @ frame 5974.
INFO: [???] STREAM c0 completed @ frame 9960.
INFO: [???] Multiplex completion at SCR=21521846.
INFO: [???] Video e0: buf= 237568 frame=005974 sector=00066056
INFO: [???] Audio c0: buf= 1792 frame=009960 sector=00002841
INFO: [???] VIDEO_STATISTICS: e0
INFO: [???] Video Stream length: 133473212 bytes
INFO: [???] Sequence headers: 334
INFO: [???] Sequence ends : 0
INFO: [???] No. Pictures : 5975
INFO: [???] No. Groups : 334
INFO: [???] No. I Frames : 334 avg. size 43026 bytes
INFO: [???] No. P Frames : 1664 avg. size 33026 bytes
INFO: [???] No. B Frames : 3978 avg. size 16115 bytes
INFO: [???] Average bit-rate : 4466800 bits/sec
INFO: [???] Peak bit-rate : 14995600 bits/sec
INFO: [???] BUFFERING min 15 Buf max 237182
INFO: [???] AUDIO_STATISTICS: c0
INFO: [???] Audio stream length 5737536 bytes.
INFO: [???] Syncwords : 9961
INFO: [???] Frames : 9961 padded
INFO: [???] Frames : 0 unpadded
INFO: [???] BUFFERING min 15 Buf max 587
**ERROR: [???] MUX STATUS: Frame data under-runs detected!

[Caple]

INFO: [???] Bit rate : 15000000 bits/sec

DVD specs allow a max of 9800kbps.
You recorded with the highest option the software gave you, right?
You need to reencode it.

[jman98]

Use either Gspot 2.60beta something or other (do NOT use the 2.2 or 2.3 versions because they don't give any useful info on MPEG files) or get the free version of the Teco Bit Rate Viewer (http://www.tecoltd.com) and feed your video into it. You may have to search a little to find the current version of Gspot. I've seen a lot of places that only have the 2.2 (or 2.3?) versions and I had to look on Google to find the 2.6X version.

I don't use dvdauthor but it appears that your video may actually peak at a bit rate of 14995 Kbps instead of the 9900 Kbps or so that is the maximum allowed for DVD. Looks like either you encoded something with an encoder that went nuts and used too high a bit rate or you recorded a video to your PC and the recording spiked too high at some point in the video. If I am right, you have no choice but to re-encode your video to a lower bit rate to get rid of the problem or if you recorded it, re-record it, but use a lower bit rate. I won't use anything above 9000 for anything I record to my PC. Using a higher value doesn't really help (ie. 9900 will look the same to you as 9000 will - trust me on this) and it just lets the recorder have more room for error as most recorders really go at least a little higher than the maximum value you set them for.

[nebbish_2112]

I didn't personally encode these videos, I d/l there from the net. Seeing as I have a collection of these PAL videos in both 704X576 and 720X576 formats, I might as well pad the 704 to 720 in TMPGEnc while I'm at it. This way I won't have to create multiple VTS to allow for the two different formats I'm working with.

One question. Does this video seem to be VBR? If I encode a video at say 8000 kbps CBR, my rate wouldn't be able to peak at 15000 kpbs, right?

[Caple]

I don't believe it can be VBR. Most softwares, if not all, won't go that high if you choose to record on VBR.
If you reencode at 8000kbps it will stay like this all the way.

[alfredsvideo]

Goto: https://www.videohelp.com/calc.htm

I've used this program on countless videos when converting them to DVD. Can't go wrong.
Good Luck, Alf.

[guns1inger]

How long and how big is the video ? From there you can work backwards to an average bitrate. Some encoders put incorrect bitrates into the headers.