[PyOV] Add torchvision to OpenVINO preprocessing converter docs (#20770)

Co-authored-by: Karol Blaszczak <karol.blaszczak@intel.com>

src/bindings/python/README.md

@@ -23,6 +23,7 @@ OpenVINO PYTHON API has the following structure:
 * [src](./src/) - folder with all source files for Python API.
     * [src/compatibility](./src/compatibility/) - sources for compatibility API, including older modules like `ngraph` and `openvino.inference_engine`.
     * [src/openvino](./src/openvino/) - Python sources for current API.
+    * [src/openvino/preprocess](./src/openvino/preprocess/) - Torchvision to OpenVINO preprocessing converter.
     * [src/pyopenvino](./src/pyopenvino/) - C++ sources for current API.
 * [tests](./tests/) - tests directory for current API.
 * [tests_compatibility](./tests_compatibility/) - tests directory for compatibility API.

src/bindings/python/docs/code_examples.md

@@ -411,4 +411,5 @@ To learn how to test your code, refer to the guide on [how to test OpenVINO™ P
 ## See also
  * [OpenVINO™ README](../../../../README.md)
  * [OpenVINO™ bindings README](../../README.md)
+ * [torchvision to OpenVINO™ preprocessing converter README](../src/openvino/preprocess/README.md)
  * [Developer documentation](../../../../docs/dev/index.md)

src/bindings/python/src/openvino/preprocess/README.md

@@ -0,0 +1,60 @@
+# Torchvision to OpenVINO preprocessing converter
+
+The Torchvision to OpenVINO preprocessing converter enables the use of an existing `torchvision.transforms` object to automatically translate it to OpenVINO preprocessing. It is then being embedded into the model, resulting in better inference performance.
+
+
+## Supported transforms
+
+Currently, the torchvision to OpenVINO preprocessing converter does not support all torchvision transforms.
+
+Supported operations:
+- `transforms.Compose`
+- `transforms.Normalize`
+- `transforms.ConvertImageDtype`
+- `transforms.Grayscale`
+- `transforms.Pad`
+- `transforms.ToTensor`
+- `transforms.CenterCrop`
+- `transforms.Resize`
+
+## Example usage
+
+```python
+preprocess_pipeline = torchvision.transforms.Compose(
+    [
+        torchvision.transforms.Resize(256, interpolation=transforms.InterpolationMode.NEAREST),
+        torchvision.transforms.CenterCrop((216, 218)),
+        torchvision.transforms.Pad((2, 3, 4, 5), fill=3),
+        torchvision.transforms.ToTensor(),
+        torchvision.transforms.ConvertImageDtype(torch.float32),
+        torchvision.transforms.Normalize(mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225]),
+    ]
+)
+
+torch_model = SimpleConvnet(input_channels=3)
+
+torch.onnx.export(torch_model, torch.randn(1, 3, 224, 224), "test_convnet.onnx", verbose=False, input_names=["input"], output_names=["output"])
+core = Core()
+ov_model = core.read_model(model="test_convnet.onnx")
+
+test_input = np.random.randint(255, size=(260, 260, 3), dtype=np.uint16)
+ov_model = PreprocessConverter.from_torchvision(
+    model=ov_model, transform=preprocess_pipeline, input_example=Image.fromarray(test_input.astype("uint8"), "RGB")
+)
+ov_model = core.compile_model(ov_model, "CPU")
+ov_input = np.expand_dims(test_input, axis=0)
+output = ov_model.output(0)
+ov_result = ov_model(ov_input)[output]
+```
+
+## Key contacts
+
+If you have any questions, feature requests or want us to review your PRs, send us a message or ping us on GitHub via [openvino-ie-python-api-maintainers](https://github.com/orgs/openvinotoolkit/teams/openvino-ie-python-api-maintainers). You can always directly contact everyone from this group.
+
+## See also
+
+* [OpenVINO™ README](../../../README.md)
+* [OpenVINO™ Core Components](../../README.md)
+* [OpenVINO™ Python API Reference](https://docs.openvino.ai/2023.0/api/ie_python_api/api.html)
+* [OpenVINO™ Python API Advanced Inference](https://docs.openvino.ai/2023.0/openvino_docs_OV_UG_Python_API_inference.html)
+* [OpenVINO™ Python API Exclusives](https://docs.openvino.ai/2023.0/openvino_docs_OV_UG_Python_API_exclusives.html)