Page 1 of 5 123 ... LastLast
Results 1 to 15 of 62

Thread: What is the workflow with Bvh?

  1. #1

    What is the workflow with Bvh?

    I have recently procured some bvh files and i was wondering if lightwave can import the bvh motion and im able to make changes to it and export it as mocap data again. I guess my goals can be explained in a few fundamental questions.

    1. Can I import the data as is and be able to preview/change the motion without having to apply it to a skeleton rig or geometry of some kind?

    2. Is it possible to use something like motion mixer to combine or blend many animations into one large sequence that can be exported back to bvh?

    3. If the answers to previous questions are NO. Does anyone know nifty software that can do the things i previously mentioned and utilize bvh data and maybe convert it to other mocap formats?
    Last edited by aaronv2; 03-30-2009 at 11:07 PM.
    ----------------------------
    Is Radiosity turned on? :)
    ----------------------------

  2. #2
    For all those interested I have found an extremely large database of Mocap files on a university database.

    http://mocap.cs.cmu.edu/

    there is also this site which offers hundreds of free bvh but also sells some too
    http://www.mocapdata.com/

    they contain ASF/AMC mocap data which can be converted using...

    AMC2BVH
    http://vipbase.net/amc2bvh/

    Apart from that I have found two usefull little applications.
    http://vipbase.net/bvhviewer/
    Is a useful mocap viewer but with no edit capabilities.

    BVHacker is a little more promising im looking into it now.
    http://davedub.co.uk/bvhacker/index.html
    Last edited by aaronv2; 03-30-2009 at 11:35 PM.
    ----------------------------
    Is Radiosity turned on? :)
    ----------------------------

  3. #3
    Super Member SplineGod's Avatar
    Join Date
    Feb 2003
    Location
    Hastings, New Zealand
    Posts
    7,731
    Quote Originally Posted by aaronv2 View Post
    1. Can I import the data as is and be able to preview/change the motion without having to apply it to a skeleton rig or geometry of some kind?
    Yes, You can import bvh files in layout which creates a skeleton with the motion applied. In modeler you can import the bvh skeleton as skelegons.

    2. Is it possible to use something like motion mixer to combine or blend many animations into one large sequence that can be exported back to bvh?
    Yes and no. LW cannot export bvh files. It can export FBX and collada. I generally use IKBoost to deal with mocap files which I use quite a bit. Theres the free stuff mentioned here and lots of commercial libraries.

    3. If the answers to previous questions are NO. Does anyone know nifty software that can do the things i previously mentioned and utilize bvh data and maybe convert it to other mocap formats?
    If you consider collada or fbx as other mocap formats LW will do that.

  4. #4
    oh wow a reply from SplineGod... i was hoping for a day like this. Im honoured.

    I will jump right into it because I do have the ability to import fbx and collada into what im using.

    As a side note however... when you say "I generally use IKBoost to deal with mocap files" Are you able to elaborate on that idea just a bit? Im really interested to learn anything from you. Where the hell is the butt kissing emoticon.
    ----------------------------
    Is Radiosity turned on? :)
    ----------------------------

  5. #5
    Super Member SplineGod's Avatar
    Join Date
    Feb 2003
    Location
    Hastings, New Zealand
    Posts
    7,731
    LOL! Ok....
    I import the bvh file to get the skeleton. It comes in with a null with bones attached. I apply IKBoost and immediately delete all the mocap data of all the bones. This is very quick and easy to do with IKB. Next I replace the null with the actual character and then use the bone tools to make the skeleton fit the new character.
    Once thats complete i reload the bvh file which again comes in with a null, bones and motion data on the bones. I apply IKB to that as well. Once IKB is applied to both rigs I can now simply copy the motion from the bvh file directly to my character and rig.
    The whole operation takes maybe 5 minues.
    I can also copy motions from any part of the bvh rig to any part of my character and rig. Its pretty useful and allows me to quickly get mocap into LW in a useful fashion.

  6. #6
    awesome! i haven't done too much experimentation with ikbooster apart from trying to replicate some tentacles not too long ago. Im going to get your technique down tonight and hopefully reach some success.

    You see? Butt kissing just got me some awesome new information from the god himself.

    EDIT: oh crap i hate to be a bother but can u elaborate how you clear the motion data from the bones easily? My idea is to save the motion out as txt with only one frame then reapplying that txt to the motion is that the correct way?
    Last edited by aaronv2; 03-31-2009 at 02:20 AM.
    ----------------------------
    Is Radiosity turned on? :)
    ----------------------------

  7. #7
    Super Member SplineGod's Avatar
    Join Date
    Feb 2003
    Location
    Hastings, New Zealand
    Posts
    7,731
    The reason I remove the motion data is to allow me to edit and tweak the bones into place without the motion being a distraction.
    Its easy enough to reapply the motion as I described.
    If you set the keyframe in IKB to all items whatever you do in the dopetrack will effect every chanel of every item in your rig.
    So if you select and delete all the keys in the dopetrack while the keyframe mode is set to All items every bit of motion will be deleted. This is much simpler then trying to do it in the graph editor. Heres some free stuff I have on IKB:
    http://www.vfxcast.com/playlist/IKBoost/
    and several hours of IKB training on DVD with support :
    http://www.kurvstudios.com/lightwave/ikbooster.php

  8. #8
    Thanks Larry you seriously keep me motivated and always ready to learn. I have one last follow up question.

    Presumably most bvh are the same? Would it be more logical to make a base skeleton i can always reference later to tweak for my model or do you suggest always adapting your skeleton rig from the bvh you load because it may contain more/less data points?

    If anyone else has mocap tips id love to hear from you. But i think I have pretty much got it all sorted. Im testing out larrys technique while i post
    ----------------------------
    Is Radiosity turned on? :)
    ----------------------------

  9. #9
    Super Member SplineGod's Avatar
    Join Date
    Feb 2003
    Location
    Hastings, New Zealand
    Posts
    7,731
    You might be able to use motion mixer to retarget mocap from the bvh file to your own rig. This can take time and some tuning.
    Another option is to create a rig that uses expressions to reference the bvh rig. Again it takes time. In the end Ive found that just making the bvh rig work with my character is the easiest.

    If you use a bvh library created by the same people and consistently uses the same skeletal setup its much easier. Its more of a pain when different libraries do things differently.

    If you can always use the same rig thats what I would do but like I said its not always the case.

  10. #10
    thankyou for all your information larry... you have effectively prooved to me why your technique is the simplest and most effective. I wont even try to attempt any of those other ways, expressions? yikes!

    Im currently having a little trouble with editing the bones... But i am going to keep trying. If i get desperate I may have to milk you guys for some more killer info.
    ----------------------------
    Is Radiosity turned on? :)
    ----------------------------

  11. #11
    YES! oh crap I got so excited when I saw everything work just how I like it after a few crashes. I think it was a bit of pride...

    Larry I want to thankyou for everything dude. If it wasnt for you I would have given up on the first try! I have posted my scene if anyone wants to check it out. Its a bit crude and not very well done but i just wanted to get the basic technique down.

    All Hail the mighty splinegod.
    Attached Files Attached Files
    ----------------------------
    Is Radiosity turned on? :)
    ----------------------------

  12. #12
    Super Member SplineGod's Avatar
    Join Date
    Feb 2003
    Location
    Hastings, New Zealand
    Posts
    7,731
    No problem. Glad to see its working

  13. #13
    Newbie Member
    Join Date
    Jun 2008
    Location
    USA
    Posts
    14

    BVH from Endorphin

    SplineGod,
    I have been following your advice to arronv2. Do you have any idea why bvh content exported from Endorphin doesn't come in properly but a bvh file that I download works fine?

    Basically what I do is to import a .bvh file into LW 9.3. This brings in the rig with motion. I then replace the "hips" object with the human model.

    This method works fine with downloaded data but when I bring in a .bvh from Endorphin everything goes toheck.
    Any ideas?

  14. #14
    Super Member SplineGod's Avatar
    Join Date
    Feb 2003
    Location
    Hastings, New Zealand
    Posts
    7,731
    Im not sure. Ive had different version of LW that sometimes has broken bvh import.
    If generic bvh files work but not the endorphin kind then Id guess the problems is there.
    Download this free app called bvhacker and see if it will import the endorphin bvh files.
    If it does then resave them out of bvhacker and they should work in LW.
    http://davedub.co.uk/bvhacker/index.html
    Also see if the same bvh files will work in Blender which i s also free.

  15. #15
    Newbie Member
    Join Date
    Jun 2008
    Location
    USA
    Posts
    14
    Thanks- Great observation. I actually did that before and just did it again with the same negative result.

    I think it has something to do with the way Endorphin handles the T or initial pose. All play well in bvHacker but the exported version gets scrambled. I have to get with the Natural Motion people.

    THX

Page 1 of 5 123 ... LastLast

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •