def force(backend_name, bbox, childprocess):
backend_class = backend_dict[backend_name]
if select_childprocess(childprocess, backend_class):
log.debug('running "%s" in child process', backend_name)
return childprocess_grab(backend_name, bbox)
else:
obj = backend_class()
im = obj.grab(bbox)
return im
def _grab(childprocess, backend=None, bbox=None, filename=None):
if bbox:
x1, y1, x2, y2 = bbox
if x2 <= x1:
raise ValueError("bbox x2<=x1")
if y2 <= y1:
raise ValueError("bbox y2<=y1")
if childprocess:
log.debug('running "%s" in child process', backend)
return childprocess_grab(_grab_simple, backend, bbox)
else:
return _grab_simple(backend, bbox, filename)
def auto(bbox, childprocess):
im = None
for backend_class in backends(childprocess):
backend_name = backend_class.name
try:
if select_childprocess(childprocess, backend_class):
log.debug('running "%s" in child process', backend_name)
im = childprocess_grab(backend_name, bbox)
else:
obj = backend_class()
im = obj.grab(bbox)
break
except Exception:
msg = traceback.format_exc()
log.debug(msg)
if not im:
msg = "All backends failed!"
raise FailedBackendError(msg)
return im