add preprocess for h36m camera

scripts/dataset/pre_h36m_camera.py

@@ -0,0 +1,105 @@
+import os
+from os.path import join
+from glob import glob
+import numpy as np
+import cv2
+from easymocap.mytools.camera_utils import write_camera
+
+def rotation_matrix(args):
+
+    (x, y, z) = args
+
+    X = np.vstack([[1, 0, 0], [0, np.cos(x), -np.sin(x)],
+                   [0, np.sin(x), np.cos(x)]])
+    Y = np.vstack([[np.cos(y), 0, np.sin(y)], [0, 1, 0],
+                   [-np.sin(y), 0, np.cos(y)]])
+    Z = np.vstack([[np.cos(z), -np.sin(z), 0], [np.sin(z),
+                                                np.cos(z), 0], [0, 0, 1]])
+
+    return (X.dot(Y)).dot(Z)
+
+def read_cam_parameters(xml_path, sbj_id, cam_id):
+    import xml.etree.ElementTree
+
+    # use the notation from 0 -- more practical to access array
+    sbj_id = sbj_id - 1
+    cam_id = cam_id - 1
+
+    n_sbjs = 11
+    n_cams = 4
+
+    root = xml.etree.ElementTree.parse(xml_path).getroot()
+
+    for child in root:
+        if child.tag == 'w0':
+            all_cameras = child.text
+            tokens = all_cameras.split(' ')
+            tokens[0] = tokens[0].replace('[', '')
+            tokens[-1] = tokens[-1].replace(']', '')
+
+            start = (cam_id * n_sbjs) * 6 + sbj_id * 6
+            extrs = tokens[start:start + 6]
+
+            start = (n_cams * n_sbjs * 6) + cam_id * 9
+            intrs = tokens[start:start + 9]
+
+            rot = rotation_matrix(np.array(extrs[:3], dtype=float))
+
+            rt = rot
+            t = np.array(extrs[3:], dtype=float)
+
+            f = np.array(intrs[:2], dtype=float)
+            c = np.array(intrs[2:4], dtype=float)
+
+            distortion = np.array(intrs[4:], dtype=float)
+
+            k = np.hstack((distortion[:2], distortion[3:5], distortion[2:3]))
+            return (rt, t, f, c, k)
+
+def process_camera(xml_path, seq, act, cams):
+    cameras = {}
+    for i, cam in enumerate(cams, 1):
+        (rt, t, f, c, k) = read_cam_parameters(xml_path, int(seq.replace('S', '')), i)
+        K = np.eye(3)
+        K[0, 0] = f[0]
+        K[1, 1] = f[1]
+        K[0, 2] = c[0]
+        K[1, 2] = c[1]
+        cameras[cam] = {
+            'K': K,
+            'R': rt,
+            'T': t.reshape(3, 1)/1000,
+            'dist': k.reshape(1, 5)
+        }
+    return cameras
+
+def convert_h36m_easymocap(H36M_ROOT, OUT_ROOT, seqs, cams):
+    xml_path = join(H36M_ROOT, 'metadata.xml')
+    for seq in seqs:
+        print('convert {}'.format(seq))
+        # path with GT 3D pose
+        pose_path = join(H36M_ROOT, seq, 'MyPoseFeatures', 'D3_Positions_mono')
+        action_list = glob(join(pose_path, '*.cdf'))
+        action_list = list(set([os.path.basename(seq).split('.')[0] for seq in action_list]))
+        action_list.sort()
+
+        for action in action_list:
+            print('  ', action)
+            outdir = join(OUT_ROOT, seq, action)
+            # conver cameras
+            cameras = process_camera(xml_path, seq, action, cams)
+            write_camera(cameras, outdir)
+
+if __name__ == '__main__':
+    import argparse
+    parser = argparse.ArgumentParser()
+    parser.add_argument('path', type=str, help='path to h36m dataset')
+    parser.add_argument('out', type=str, help='path to output')
+    parser.add_argument('--num', type=int, default=1)
+    parser.add_argument('--debug', action='store_true')
+    args = parser.parse_args()
+
+    seqs = ['S1', 'S5', 'S6', 'S7', 'S8', 'S9', 'S11']
+    cams = ['54138969', '55011271', '58860488', '60457274']
+    XML_PATH = join(args.path, 'metadata.xml')
+    convert_h36m_easymocap(args.path, args.out, seqs, cams)