Incorrect video length reported by Windows Media Player and others

[vcmohan]

I have been trying to author a DVD from my home digicam recording. When I make the elemental streams of m2v and mp2, I find that the windows media player reports a very small duration for the m2v file and correct duration for the mp2 file. If these are multiplexed into mpeg file then the WMP shows correct length. However when these are converted as VOBs then WMP once again reports wrong length (reports same as for the corresponding m2v file. The DVD burned however is correct.

I run into problems for setting Chapters by DVDAuthorGUI. I also get into problems in trying to use DVDSubtitlerWorkshop. It appears that these work same way as WMP and so I can not set any chapter point or include any subtitle beyond the length incorrectly reported.

When I try to play these on WMP the slider reaches the end at its reported incorrect time but video is continued to play till end with the time display remaining at same incorrect point.

I am unable to understand why this happens and how can I get over this problem.

[setarip_old]

Hi!

What is the format (video and audio) of your original capture from the "digicam"?

[vcmohan]

My digicam records on mini DV tape. I capture it with ulead video studio, convert to dv 2 AVI format. NTSC 29.97fps. Audio is 32khz stereo. Virtualdub reports Video:720X480 decompressor as internal DV decompressor.Data rate 28771kbps (0.02% overhead). Audio:32khz,stereo, 1024kbps(0.06% overhead)

[setarip_old]

When you play the .AVI, does the player reflect the correct amount of time?

2) What software/procedures are you using to create the .M2V and .MP2 streams?

[Susana]

http://forum.doom9.org/showthread.php?p=855948#post855948

[vcmohan]

AVI file length is correctly reported by Virtualdub and Windows Media Player. I use HCEnc or QEnc for creating M2V files. I use Besweet for converting wav audio to MP2 files.
@susana... As I try to make chapters or subtitles I need the time or frame numbers to input. None of the software I tried (DVDAuthor, SRT2SUP, Subtitle workshop) could be used for this due to incorrect length. The length reported is 50 to 30% of what it should be.
Possibly the length is roughly calculated using max possible frame size bits and use it to divide the file length. Due to compression this method will not work.

In case of MPEGSOURCE for Avisynth DGIndex does the work, but I am in the process of creating chapters and subtitle stream.

[setarip_old]

You might want to run the .M2V stream through "ReStream" (freeware)

[manono]

Hi-

In case of MPEGSOURCE for Avisynth DGIndex does the work, but I am in the process of creating chapters and subtitle stream.

I don't understand. How does that preclude you from making a D2V and then using it in an AviSynth script file for opening in VDub(Mod) and getting either frame numbers or time? As explained in your other thread, most players won't give you the correct video length.

As an alternative, make a quick 1-pass AVI of the video at quant 3 using the XviD codec, and then use that for subs creation. That's what I do when I'm making subtitles.

[Susana]

As an alternative, make a quick 1-pass AVI of the video at quant 3 using the XviD codec, and then use that for subs creation. That's what I do when I'm making subtitles.
Same as I do when synchronizing subtitles with subtitle workshop. Times reported are slightly different from real. With avi no problem.

[vcmohan]

Its true I can get correct frame or time info from Avisynth+ virtualdub. However neither DVDAuthorGui nor the subtitle workshop accept for chapter points or title placement, frame numbers or times larger than what they wrongly evaluated . I will try creating them manually and try to use the resulting file in the final authoring.

But this is an inconvenience that I am just pointing out to know whether any tool or proceedure exists that evaluate correct times while authoring for subtitles and chapter points.

[setarip_old]

I am just pointing out to know whether any tool or proceedure exists that evaluate correct timesAgain, have you tried to run the .M2V stream through "ReStream" (freeware)?

[vcmohan]

Again, have you tried to run the .M2V stream through "ReStream" (freeware)?

I do not know what parameters I need to change while using restream. However on my hunch I tried changing nominal bit rate from 8000 to 4000. Then for that restream-ed file the duration reported by the WMP is correct. Since while using VBR the bit rate varies, I am not sure that this will give chapter points or menu start stop times correctly.