fix cpp_infer in SSD (#231)

tools/cpp_infer.py

@@ -78,7 +78,9 @@ def get_extra_info(im, arch, shape, scale):
         logger.info('Extra info: im_size')
         info.append(im_size)
     elif 'SSD' in arch:
-        pass
+        im_shape = np.array([shape[:2]]).astype('int32')
+        logger.info('Extra info: im_shape')
+        info.append([im_shape])
     elif 'RetinaNet' in arch:
         input_shape.extend(im.shape[2:])
         im_info = np.array([input_shape + [scale]]).astype('float32')
@@ -190,6 +192,7 @@ def Preprocess(img_path, arch, config):
 def infer():
     model_path = FLAGS.model_path
     config_path = FLAGS.config_path
+    res = {}
     assert model_path is not None, "Model path: {} does not exist!".format(
         model_path)
     assert config_path is not None, "Config path: {} does not exist!".format(
@@ -198,6 +201,9 @@ def infer():
         conf = yaml.safe_load(f)
 
     img_data = Preprocess(FLAGS.infer_img, conf['arch'], conf['Preprocess'])
+    if 'SSD' in conf['arch']:
+        img_data, res['im_shape'] = img_data
+        img_data = [img_data]
 
     if conf['use_python_inference']:
         place = fluid.CUDAPlace(0)
@@ -253,7 +259,6 @@ def infer():
         is_bbox_normalized = True if 'SSD' in conf['arch'] else False
 
         out = outs[-1]
-        res = {}
         lod = out.lod() if conf['use_python_inference'] else out.lod
         lengths = offset_to_lengths(lod)
         np_data = np.array(out) if conf[