VP12 troubleshooting possible codec problem

TeetimeNC wrote on 3/20/2014, 2:30 PM
An associate is having a problem with out-of-sync audio in certain renders. I can render the same source to the same output on my VP12 and sync is maintained. Further, my associate even has problems playing these source videos on the timeline - it is often sluggish or non responsive. We have similar PCs so I am suspecting there may be a codec problem on her PC. I have some questions regarding my planned troubleshooting assumptions and approach. Are any of these invalid?

1. Since VP12 is VFW I assume I only need to check for differences in the VFW codecs on the two machines.
2. Since the problem PC has trouble playing the source video, I'm thinking it is on the decode side of things that the problem exists.
3. She does a subset of the types of work I do. Because of this I assume a good starting place is to eliminate any redundant VFW codecs she has that are not on my PC (after creating a restore point just in case I'm wrong).

Also, is there any way to determine what codec Vegas is using to decode source video or audio?

Thanks in advance.

/jerry

Comments

NormanPCN wrote on 3/20/2014, 5:45 PM
1. Since VP12 is VFW I assume I only need to check for differences in the VFW codecs on the two machines.

Disagree. Vegas does not install any codecs into Vfw or any other codec subsystem of Windows including DirectShow and Media Foundation. At least with Gspot I cannot see anything, nor searching the registry.

If you have AVI files, then Vegas will go through Vfw to decode those.

You can tell what Vegas is using to decode by right clicking, in the project media window, on the media, select properties and go to the general tab. At the bottom of that Vegas tells you which of its decode DLLs it is using to read the file.

aviplug => The Vfw interface. Now you look into Vfw.
qt7plug => the quicktime interface. Now you look into Quicktime.
Anything else is pure Vegas.
TeetimeNC wrote on 3/20/2014, 6:19 PM
>aviplug => The Vfw interface. Now you look into Vfw.

NormanPCN, your response is informative - thanks. One question, once I have determined that Vegas is using the aviplug, can I tell which AVI codec it is using? There may be several installed.

/jerry
videoITguy wrote on 3/20/2014, 6:26 PM
heard of MEDIA INFO ?
TeetimeNC wrote on 3/20/2014, 11:02 PM
>heard of MEDIA INFO ?

I have used Media Info, but mostly I use Gspot which tells me what was used to create the source video and can tell me what codecs could be used to play the media, but not which of possibly several available codecs Vegas will use to play (decode) the source media. That is the question I am trying to resolve. So far from what I can gather from searches, the only way is to disable or remove the candidate codecs one at a time until Vegas can't decode the source media. Then you know which codec Vegas was using. I'm hoping for a better way. It would be great if in the general media tab discussed earlier if Vegas also identified the actual codec being used but that's not the case.

/jerry
videoITguy wrote on 3/21/2014, 12:17 AM
Good heavens, it is not complicated. A codec encoded stream is decoded by the codec decoder - identifying the codec is what Media Info does - albeit a codec descriptive name. The earlier suggestion was to identify the exact library programming module that the codec will be housed within.
So everything has now been described by name, what more are you looking for?
For example an .avi container, may have uncompressed (no codec required) or it might be encoded by Cineform, or Lagarith, or Indeo.
Usually Sony uses Mainconcept to encode /decode Mpeg2 stream, etc...

If you want to compare codecs on one pc versus another - GSPOT offers a great summary report for each installation.
Windows OS functionality offers a similar report comparison through dxdiag - although this will word somewhat differently for each install version.

If you want to compare how many Mpeg decoders are on a given installation, Microsoft offers a good value free optional utility to examine your system. This is particularly helpful if you have been installing optional ffmpg libraries (sometimes comes with given software).
TeetimeNC wrote on 3/21/2014, 8:52 AM
> Good heavens, it is not complicated. A codec encoded stream is decoded by the codec decoder - identifying the codec is what Media Info does

Easy for you to say ;-). Suppose you have two codecs installed, either of which can decode a particular video format. How do you determine which is being used? Will Media Info and Vegas always select the same one. Further, lets say we install Vegas on a new Windows install. Then we install K-lite and ffdshow. It is my assumption in this absurd example that Vegas could then be using K-lite or ffdshow codecs in place of original Vegas codecs for certain formats. If this is true, would the same decoder used by Vegas also show up as the codec in Media Info for that video file?

/jerry

videoITguy wrote on 3/21/2014, 11:08 AM
identify as earlier suggested the programming library used by the app - namely vegas, here, to narrow out these comparisons between different installations.
TeetimeNC wrote on 3/21/2014, 12:08 PM
>identify as earlier suggested the programming library used by the app - namely vegas, here, to narrow out these comparisons between different installations.

Yes, I understand this. My question remains, given that you have narrowed it to 3, or 5 or whatever codecs that Vegas might be using to decode a particular video file, is there a trick for determining which file it is using. Because, if Vegas is the only app that is having play/encode problem with a particular type of video file, it would be useful to be able to identify the specific codec that needs to be disabled, removed or reinstalled.

I've learned of this Codec Tweaker Tool that others are using for troubleshooting codecs. I haven't tried it yet because I was able to solve the problem in my first post "the old fashion way" by deleting codecs (most suspect codecs first) on the problem PC until Vegas started working properly. But I am thinking a tool like this which claims to let you temporarily disable codecs would have been a timesaver for me. Caveat - this is the standalone version of a tool that is included with K-lite codec installs. I know K-lite gets some bad press here, and that makes me hesitant to try their tool (even though it can be installed standalone). But I will probably give it a try next time I encounter a problem like this.

/jerry