[GSoC] Blockwise Quantization Tool (#265)

* Blockwise quantization tool

* add missing type hints

* add min python version check

* refactoring

Author: DaniAffCH

tools/quantize/README.md

@@ -7,7 +7,7 @@ Install dependencies before trying quantization:
 pip install -r requirements.txt
 ```
 
-## Usage
+## Quantization Usage
 
 Quantize all models in the Zoo:
 ```shell
@@ -52,6 +52,16 @@ models = dict(
 python quantize-inc.py model1
 ```
 
+## Blockwise quantization usage
+
+`block_quantize.py` requires Python>=3.7
+
+To perform weight-only blockwise quantization:
+
+```shell
+python block_quantize.py --input_model INPUT_MODEL.onnx --output_model OUTPUT_MODEL.onnx --block_size {block size} --bits {8,16}
+```
+
 ## Dataset
 Some models are quantized with extra datasets.
 - [MP-PalmDet](../../models/palm_detection_mediapipe) and [MP-HandPose](../../models/handpose_estimation_mediapipe) are quantized with evaluation set of [FreiHAND](https://lmb.informatik.uni-freiburg.de/resources/datasets/FreihandDataset.en.html). Download the dataset from [this link](https://lmb.informatik.uni-freiburg.de/data/freihand/FreiHAND_pub_v2_eval.zip). Unpack it and replace `path/to/dataset` with the path to `FreiHAND_pub_v2_eval/evaluation/rgb`.