enh: add ability to read json file for info

Author: satra

examples/fmri_ants_openfmri.py

@@ -562,13 +562,22 @@ def get_subjectinfo(subject_id, base_dir, task_id, model_id):
                                          'task%03d_run*' % (idx + 1))))
         runs = [int(val[-3:]) for val in files]
         run_ids.insert(idx, runs)
-    task_scan_key = os.path.join(base_dir, subject_id, 'BOLD', 
+    json_info = os.path.join(base_dir, subject_id, 'BOLD', 
                                  'task%03d_run%03d' % (task_id, run_ids[0]), 
-                                 'scan_key.txt')
-    if os.path.exists(task_scan_key):
-        TR = np.genfromtxt(task_scan_key)[1]
+                                 'bold_scaninfo.json')
+    if os.path.exists(json_info):
+        import json
+        with open(json_info, 'rt') as fp:
+            data = json.loads(fp)
+            TR = data['global']['const']['RepetitionTime']/1000.
     else:
-        TR = np.genfromtxt(os.path.join(base_dir, 'scan_key.txt'))[1]
+        task_scan_key = os.path.join(base_dir, subject_id, 'BOLD', 
+                                 'task%03d_run%03d' % (task_id, run_ids[0]), 
+                                 'scan_key.txt')
+        if os.path.exists(task_scan_key):
+            TR = np.genfromtxt(task_scan_key)[1]
+        else:
+            TR = np.genfromtxt(os.path.join(base_dir, 'scan_key.txt'))[1]
     return run_ids[task_id - 1], conds[task_id - 1], TR
 
 """