COMP 599 - BVH Blender Movie Instructions

This page describes instructions on how to render a movie of a BVH sequence with ambient occlusion and motion blur using Blender. You should plan ahead as this step can be time consuming depending on the length of your motion sequence. That is, you will likely need to let your computer render for a few hours! Use the following steps as a general guide for setting up and rendering your movie, but feel free to experiment and do your own thing!

  1. Download and install Blender. Note that you will also need to install Python, and you should be careful to install the exact version that Blender asks (if it isn't correct it will complain, and you'll likely not be able to use any scripts). If you missed the 15 minute tutorial in class on using Blender, you may want to read the getting started tutorial in the tutorial archive, or search for video tutorials on youtube.

  2. You'll also need a script to help build geometry for the armature you will load from the bvh file. Download the python script at this page. Put the script in your .blender/scripts folder. The location of this folder will vary depending on how you install Blender. On windows, this will either be under the "Program Files" folder or in a user folder such as "C:\Documents and Settings\kry\Application Data\Blender Foundation\Blender\.blender\scripts" on XP or "C:\Documents\kry\AppData\Blender Foundation\Blender\.blender\scripts" on Vista. Check that the script is loaded by running Blender, and then selecting scripts from the button at the top left the window (the button has a tool tip to tell you that the button lets you select the window type). Click the scripts button that appears when you change the window type to scripts, and verify that "Armature Modeler" appears under the "Animation" entry. If it doesn't show up, or if other items are empty (or if the import options are missing in the next step), then your scripts are likely not installed correctly. Check for errors and repeat! Put the top window back to "User Preferences" type when you are done so you have access to the menu bar.

  3. Now, load out.bvh using the menu "File -> Import -> MotionCapture (.bvh)...". When you click on the "Import BVH" button, "As Armature" will be selected. Click OK.

  4. After loading, the armature will be selected by default. You'll want to rotate it 90 in x so that it is walking on the x-y plane instead of the x-z plane. Press 'n', then click the value next to RotX and set it to 90.

  5. Press 'numberpad-0' to see the camera view. Use the middle mouse button to rotate out of the camera view. Use the scroll wheel to zoom in and out. To see the animation that you loaded you'll want to bring up the timeline: right click exactly on the line between the perspective panel and select "split area", then left click in the bottom panel to divide the area. Click the left top most button in the area you created, and select timeline from the menu. Use the left mouse button to drag in the timeline to see the animation.

  6. When you started Blender, the default scene included a cube called "Cube". Use the cube to create a template bone geometry. Select it by right clicking on it. Press n to show the transform properties if they are not already showing. Set the scale in y to be 3, then translate the scaled cube so that its long direction is going down the y axis. Press 'tab' to go into edit mode, and then set Median Y to 1.0 in the transform properties window, then press tab again to return to object mode.

  7. Select the armature by right clicking on it, then select "Pose Mode" from the mode combo box (the one that was changing between object and edit when you press tab). Press 'a' to select all the armature bones. Now select in your scripts window "Scripts->Animation->Armature Modeler". If you do not see the whole interface then make the window a bit larger. Change the bone type from "Octaedron" to "custom" and provide the name "Cube" where it asks for OB. Feel free to follow the instructions on Malefico's page to create different geometry, or tune the shapes in other ways.

  8. Create a plane for your character to walk on by selecting from the menu Add->Mesh->Plane. Scale and position your plane by adjusting the transform properties (press 'n' to bring them up). Location 0,0,0 and scale 50,50,50 should work OK. You may want to translate your original Cube below the plane so it is hidden from view.

  9. Change the colour of your character by selecting the Cube and pressing F5 to bring up the shading buttons, then select the small red sphere to select the material buttons. Under Material, click on the grey rectangle next to "Col" to select a different colour.

  10. Turn on ambient occlusion rendering by pressing the world "World buttons" when you have the shading buttons selected. Pressing F5 multiple times will take you there. It is the last button on the right. Select the "Amb Occ" tab and press the "Ambient Occlusion" button. The default settings are fine.

  11. Change the position of the camera so you can properly see your character throughout the animation. Select the camera by right clicking it, press 'numberpad-0' for the camera view, 'n' to change change its position and orientation.

  12. Change the position of the light so you can properly see your character. Right click the light drag it around, or set its transform properties.

  13. Press F12 to do a test render, and adjust everything as you see fit.

  14. Press F10 to select the "Scene" button and make sure the left most button with tooltip "Render buttons" is selected. Under "Format" choose "AVI Codec" instead of "jpeg", select xvid, and configure the codec for high quality. Just under file format combo box is a FPS setting. Since the natural point system records at 100 Hz, you should change the value to 100. In the "Anim" tab to the left, change the step setting at the bottom to be 10 so that you're not rendering every frame, and set the End frame to be whatever you want as the end frame (check by scrubbing the cursor in the timeline window). Finally, in the "Render" tab press the "MBLUR" button and set the Bf parameter to some suitable parameter, such as 5 (i.e., so it renders the blur over a longer period of time). Press F12 once more for a test render to see that everything is satisfactory for the current frame.

  15. Finally, when you are ready, press the "ANIM" button on the "Anim" tab to render the whole animation to disk. This will likely take a few hours, so you might want to test with a short sequence first and make any adjustments based on the result.