diff --git a/data_juicer/config/config.py b/data_juicer/config/config.py
index eac02065c..aba3dd31c 100644
--- a/data_juicer/config/config.py
+++ b/data_juicer/config/config.py
@@ -429,7 +429,7 @@ def init_setup_from_cfg(cfg: Namespace):
         cfg.np = sys_cpu_count
         logger.warning(
             f'Number of processes `np` is not set, '
-            f'Set it to cpu count [{sys_cpu_count}] as default value.')
+            f'set it to cpu count [{sys_cpu_count}] as default value.')
     if cfg.np > sys_cpu_count:
         logger.warning(f'Number of processes `np` is set as [{cfg.np}], which '
                        f'is larger than the cpu count [{sys_cpu_count}]. Due '
diff --git a/tests/tools/test_process_data.py b/tests/tools/test_process_data.py
index 1c923a87b..ee032adce 100644
--- a/tests/tools/test_process_data.py
+++ b/tests/tools/test_process_data.py
@@ -66,5 +66,102 @@ def test_status_code_1(self):
         self.assertFalse(osp.exists(tmp_out_path))
 
 
+class ProcessDataRayTest(DataJuicerTestCaseBase):
+
+    def setUp(self):
+        super().setUp()
+
+        self._auto_create_ray_cluster()
+
+        self.tmp_dir = tempfile.TemporaryDirectory().name
+        if not osp.exists(self.tmp_dir):
+            os.makedirs(self.tmp_dir)
+
+    def _auto_create_ray_cluster(self):
+        if not subprocess.call('ray status', shell=True):
+            # ray cluster already exists, return
+            self.tmp_ray_cluster = False
+            return
+
+        self.tmp_ray_cluster = True
+        head_port = '6379'
+        head_addr = '127.0.0.1'
+        rank = int(os.environ.get('RANK', 0))
+
+        if rank == 0:
+            cmd = f"ray start --head --port={head_port} --node-ip-address={head_addr}"
+        else:
+            cmd = f"ray start --address={head_addr}:{head_port}"
+
+        print(f"current rank: {rank}; execute cmd: {cmd}")
+
+        result = subprocess.call(cmd, shell=True)
+        if result != 0:
+            raise subprocess.CalledProcessError(result, cmd)
+        
+    def _close_ray_cluster(self):
+        subprocess.call('ray stop', shell=True)
+
+    def tearDown(self):
+        super().tearDown()
+
+        if osp.exists(self.tmp_dir):
+            shutil.rmtree(self.tmp_dir)
+
+        import ray
+        ray.shutdown()
+
+        if self.tmp_ray_cluster:
+            self._close_ray_cluster()
+
+    def test_ray_image(self):
+        tmp_yaml_file = osp.join(self.tmp_dir, 'config_0.yaml')
+        tmp_out_path = osp.join(self.tmp_dir, 'output_0.json')
+        text_keys = 'text'
+
+        data_path = osp.join(osp.dirname(osp.dirname(osp.dirname(osp.realpath(__file__)))),
+            'demos', 'data', 'demo-dataset-images.jsonl')
+        yaml_config = {
+            'dataset_path': data_path,
+            'executor_type': 'ray',
+            'ray_address': 'auto',
+            'text_keys': text_keys,
+            'image_key': 'images',
+            'export_path': tmp_out_path,
+            'process': [
+                {
+                    'image_nsfw_filter': {
+                        'hf_nsfw_model': 'Falconsai/nsfw_image_detection',
+                        'trust_remote_code': True,
+                        'score_threshold': 0.5,
+                        'any_or_all': 'any',
+                        'mem_required': '8GB'
+                    },
+                    'image_aspect_ratio_filter':{
+                        'min_ratio': 0.5,
+                        'max_ratio': 2.0
+                    }
+                }
+            ]
+        }
+
+        with open(tmp_yaml_file, 'w') as file:
+            yaml.dump(yaml_config, file)
+
+        status_code = subprocess.call(
+            f'python tools/process_data.py --config {tmp_yaml_file}', shell=True)
+
+        self.assertEqual(status_code, 0)
+        self.assertTrue(osp.exists(tmp_out_path))
+
+        import ray
+        res_ds = ray.data.read_json(tmp_out_path)
+        res_ds = res_ds.to_pandas().to_dict(orient='records')
+
+        self.assertEqual(len(res_ds), 3)
+        for item in res_ds:
+            self.assertIn('aspect_ratios', item['__dj__stats__'])
+
+
 if __name__ == '__main__':
     unittest.main()