Balint-H / bvh-python

Python module for parsing BVH (Biovision hierarchical data) mocap files

hierarchyset and bvhset

Hierarchyset is an abstract class you can implement to process and export data into hierarchical mocap formats. The key part to implement in a child class is the load_mocap method. You need to open the relevant files and construct your Segments. An example implementation is shown in bvhset, that reads in a bvh file using the open source package in this repo. To save to a bvh file you can call save_bvh once a file has been loaded. Example large BVH file included from Harvey et al., 2020.

bvh-python

Python module for parsing BVH (Biovision hierarchical data) mocap files. Forked from original repo from user "20tab" to improve effeciency and extend with features.

Instance Bvh object from .bvh file

>>> from bvh import Bvh
>>> with open('tests/test_freebvh.bvh') as f:
>>>    mocap = Bvh(f.read())

Get mocap tree

>>> [str(item) for item in mocap.root]
['HIERARCHY', 'ROOT mixamorig:Hips', 'MOTION', 'Frames: 69', 'Frame Time: 0.0333333']

Get ROOT OFFSET

>>> next(mocap.root.filter('ROOT'))['OFFSET']
['0.0000', '0.0000', '0.0000']

Get JOINT OFFSET

>>> mocap.joint_offset('mixamorig:Head')
(-0.0, 10.3218, 3.1424)

Get Frames

>>> mocap.nframes
69

Get Frame Time

>>> mocap.frame_time
0.0333333

Get JOINT CHANNELS

>>> mocap.joint_channels('mixamorig:Neck')
['Zrotation', 'Yrotation', 'Xrotation']

Get Frame CHANNEL

>>> mocap.frame_joint_channel(22, 'mixamorig:Spine', 'Xrotation')
11.8096

Get all JOINT names

>>> mocap.get_joints_names()
['mixamorig:Hips', 'mixamorig:Spine', 'mixamorig:Spine1', 'mixamorig:Spine2', 'mixamorig:Neck', 'mixamorig:Head', 'mixamorig:HeadTop_End', 'mixamorig:LeftEye', 'mixamorig:RightEye', 'mixamorig:LeftShoulder', 'mixamorig:LeftArm', 'mixamorig:LeftForeArm', 'mixamorig:LeftHand', 'mixamorig:LeftHandMiddle1', 'mixamorig:LeftHandMiddle2', 'mixamorig:LeftHandMiddle3', 'mixamorig:LeftHandThumb1', 'mixamorig:LeftHandThumb2', 'mixamorig:LeftHandThumb3', 'mixamorig:LeftHandIndex1', 'mixamorig:LeftHandIndex2', 'mixamorig:LeftHandIndex3', 'mixamorig:LeftHandRing1', 'mixamorig:LeftHandRing2', 'mixamorig:LeftHandRing3', 'mixamorig:LeftHandPinky1', 'mixamorig:LeftHandPinky2', 'mixamorig:LeftHandPinky3', 'mixamorig:RightShoulder', 'mixamorig:RightArm', 'mixamorig:RightForeArm', 'mixamorig:RightHand', 'mixamorig:RightHandMiddle1', 'mixamorig:RightHandMiddle2', 'mixamorig:RightHandMiddle3', 'mixamorig:RightHandThumb1', 'mixamorig:RightHandThumb2', 'mixamorig:RightHandThumb3', 'mixamorig:RightHandIndex1', 'mixamorig:RightHandIndex2', 'mixamorig:RightHandIndex3', 'mixamorig:RightHandRing1', 'mixamorig:RightHandRing2', 'mixamorig:RightHandRing3', 'mixamorig:RightHandPinky1', 'mixamorig:RightHandPinky2', 'mixamorig:RightHandPinky3', 'mixamorig:RightUpLeg', 'mixamorig:RightLeg', 'mixamorig:RightFoot', 'mixamorig:RightToeBase', 'mixamorig:LeftUpLeg', 'mixamorig:LeftLeg', 'mixamorig:LeftFoot', 'mixamorig:LeftToeBase']

Get single JOINT name

>>> mocap.get_joints_names()[17]
'mixamorig:LeftHandThumb2'

Get JOINT parent index

>>> mocap.joint_parent_index('mixamorig:Neck')
3

Get JOINT parent name

>>> mocap.joint_parent('mixamorig:Head').name
'mixamorig:Neck'

Search single item

>>> [str(node) for node in mocap.search('JOINT', 'LeftShoulder')]
['JOINT LeftShoulder']

Search all items

>>> [str(node) for node in mocap.search('JOINT')]
['JOINT mixamorig:Spine', 'JOINT mixamorig:Spine1', 'JOINT mixamorig:Spine2', 'JOINT mixamorig:Neck', 'JOINT mixamorig:Head', 'JOINT mixamorig:HeadTop_End', 'JOINT mixamorig:LeftEye', 'JOINT mixamorig:RightEye', 'JOINT mixamorig:LeftShoulder', 'JOINT mixamorig:LeftArm', 'JOINT mixamorig:LeftForeArm', 'JOINT mixamorig:LeftHand', 'JOINT mixamorig:LeftHandMiddle1', 'JOINT mixamorig:LeftHandMiddle2', 'JOINT mixamorig:LeftHandMiddle3', 'JOINT mixamorig:LeftHandThumb1', 'JOINT mixamorig:LeftHandThumb2', 'JOINT mixamorig:LeftHandThumb3', 'JOINT mixamorig:LeftHandIndex1', 'JOINT mixamorig:LeftHandIndex2', 'JOINT mixamorig:LeftHandIndex3', 'JOINT mixamorig:LeftHandRing1', 'JOINT mixamorig:LeftHandRing2', 'JOINT mixamorig:LeftHandRing3', 'JOINT mixamorig:LeftHandPinky1', 'JOINT mixamorig:LeftHandPinky2', 'JOINT mixamorig:LeftHandPinky3', 'JOINT mixamorig:RightShoulder', 'JOINT mixamorig:RightArm', 'JOINT mixamorig:RightForeArm', 'JOINT mixamorig:RightHand', 'JOINT mixamorig:RightHandMiddle1', 'JOINT mixamorig:RightHandMiddle2', 'JOINT mixamorig:RightHandMiddle3', 'JOINT mixamorig:RightHandThumb1', 'JOINT mixamorig:RightHandThumb2', 'JOINT mixamorig:RightHandThumb3', 'JOINT mixamorig:RightHandIndex1', 'JOINT mixamorig:RightHandIndex2', 'JOINT mixamorig:RightHandIndex3', 'JOINT mixamorig:RightHandRing1', 'JOINT mixamorig:RightHandRing2', 'JOINT mixamorig:RightHandRing3', 'JOINT mixamorig:RightHandPinky1', 'JOINT mixamorig:RightHandPinky2', 'JOINT mixamorig:RightHandPinky3', 'JOINT mixamorig:RightUpLeg', 'JOINT mixamorig:RightLeg', 'JOINT mixamorig:RightFoot', 'JOINT mixamorig:RightToeBase', 'JOINT mixamorig:LeftUpLeg', 'JOINT mixamorig:LeftLeg', 'JOINT mixamorig:LeftFoot', 'JOINT mixamorig:LeftToeBase']

Get joint's direct children

>>> mocap.joint_direct_children('mixamorig:Hips')
[JOINT mixamorig:Spine, JOINT mixamorig:RightUpLeg, JOINT mixamorig:LeftUpLeg]