fix image2test args forwarding (#19648)

* fix image2test args forwarding

* fix issues

* Proposing the update to the PR.

* Fixup.
Co-authored-by: Nicolas Patry <patry.nicolas@protonmail.com>

src/transformers/pipelines/image_to_text.py

@@ -44,8 +44,20 @@ class ImageToTextPipeline(Pipeline):
             TF_MODEL_FOR_VISION_2_SEQ_MAPPING if self.framework == "tf" else MODEL_FOR_VISION_2_SEQ_MAPPING
         )
 
-    def _sanitize_parameters(self, **kwargs):
-        return {}, {}, {}
+    def _sanitize_parameters(self, max_new_tokens=None, generate_kwargs=None):
+        forward_kwargs = {}
+        if generate_kwargs is not None:
+            forward_kwargs["generate_kwargs"] = generate_kwargs
+        if max_new_tokens is not None:
+            if "generate_kwargs" not in forward_kwargs:
+                forward_kwargs["generate_kwargs"] = {}
+            if "max_new_tokens" in forward_kwargs["generate_kwargs"]:
+                raise ValueError(
+                    "'max_new_tokens' is defined twice, once in 'generate_kwargs' and once as a direct parameter,"
+                    " please use only one"
+                )
+            forward_kwargs["generate_kwargs"]["max_new_tokens"] = max_new_tokens
+        return {}, forward_kwargs, {}
 
     def __call__(self, images: Union[str, List[str], "Image.Image", List["Image.Image"]], **kwargs):
         """
@@ -61,6 +73,12 @@ class ImageToTextPipeline(Pipeline):
 
                 The pipeline accepts either a single image or a batch of images.
 
+            max_new_tokens (`int`, *optional*):
+                The amount of maximum tokens to generate. By default it will use `generate` default.
+
+            generate_kwargs (`Dict`, *optional*):
+                Pass it to send all of these arguments directly to `generate` allowing full control of this function.
+
         Return:
             A list or a list of list of `dict`: Each result comes as a dictionary with the following key:
 
@@ -73,13 +91,15 @@ class ImageToTextPipeline(Pipeline):
         model_inputs = self.feature_extractor(images=image, return_tensors=self.framework)
         return model_inputs
 
-    def _forward(self, model_inputs):
+    def _forward(self, model_inputs, generate_kwargs=None):
+        if generate_kwargs is None:
+            generate_kwargs = {}
         # FIXME: We need to pop here due to a difference in how `generation_utils.py` and `generation_tf_utils.py`
         #  parse inputs. In the Tensorflow version, `generate` raises an error if we don't use `input_ids` whereas
         #  the PyTorch version matches it with `self.model.main_input_name` or `self.model.encoder.main_input_name`
         #  in the `_prepare_model_inputs` method.
         inputs = model_inputs.pop(self.model.main_input_name)
-        model_outputs = self.model.generate(inputs, **model_inputs)
+        model_outputs = self.model.generate(inputs, **model_inputs, **generate_kwargs)
         return model_outputs
 
     def postprocess(self, model_outputs):

tests/pipelines/test_pipelines_image_to_text.py

@@ -86,6 +86,12 @@ class ImageToTextPipelineTests(unittest.TestCase, metaclass=PipelineTestCaseMeta
             ],
         )
 
+        outputs = pipe(image, max_new_tokens=1)
+        self.assertEqual(
+            outputs,
+            [{"generated_text": "growth"}],
+        )
+
     @require_torch
     def test_small_model_pt(self):
         pipe = pipeline("image-to-text", model="hf-internal-testing/tiny-random-vit-gpt2")