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* Documents of INC TF 3x New API

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123 changes: 123 additions & 0 deletions docs/3x/TF_Quant.md
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TensorFlow Quantization
===============

1. [Introduction](#introduction)
2. [Usage](#usage)
2.1 [Without Accuracy Aware Tuning](#without-accuracy-aware-tuning)
2.2 [With Accuracy Aware Tuning](#with-accuracy-aware-tuning)
2.3 [Specify Quantization Rules](#specify-quantization-rules)
3. [Examples](#examples)

## Introduction

The INC 3x New API supports quantizing both TensorFlow and Keras model with or without accuracy aware tuning.

For the detailed quantization fundamentals, please refer to the document for [Quantization](../quantization.md).


## Get Started


### Without Accuracy Aware Tuning


This means user could leverage Intel(R) Neural Compressor to directly generate a fully quantized model without accuracy aware tuning. It's user responsibility to ensure the accuracy of the quantized model meets expectation.

``` python
# main.py

# Original code
model = tf.keras.applications.resnet50.ResNet50(weights="imagenet")
val_dataset = ...
val_dataloader = MyDataloader(dataset=val_dataset)

# Quantization code
from neural_compressor.tensorflow import quantize_model, StaticQuantConfig

quant_config = StaticQuantConfig()
qmodel = quantize_model(
model=model,
quant_config=quant_config,
calib_dataloader=val_dataloader,
)
qmodel.save("./output")
```

### With Accuracy Aware Tuning

This means user could leverage the advance feature of Intel(R) Neural Compressor to tune out a best quantized model which has best accuracy and good performance. User should provide `eval_fn` and `eval_args`.

``` python
# main.py

# Original code
model = tf.keras.applications.resnet50.ResNet50(weights="imagenet")
val_dataset = ...
val_dataloader = MyDataloader(dataset=val_dataset)


def eval_acc_fn(model) -> float:
...
return acc


# Quantization code
from neural_compressor.common.base_tuning import TuningConfig
from neural_compressor.tensorflow import autotune

# it's also supported to define custom_tune_config as:
# TuningConfig(StaticQuantConfig(weight_sym=[True, False], act_sym=[True, False]))
custom_tune_config = TuningConfig(
config_set=[
StaticQuantConfig(weight_sym=True, act_sym=True),
StaticQuantConfig(weight_sym=False, act_sym=False),
]
)
best_model = autotune(
model=model,
tune_config=custom_tune_config,
eval_fn=eval_acc_fn,
calib_dataloader=val_dataloader,
)
best_model.save("./output")
```

### Specify Quantization Rules
Intel(R) Neural Compressor support specify quantization rules by operator name or operator type. Users can set `local` in dict or use `set_local` method of config class to achieve the above purpose.

1. Example of setting `local` from a dict
```python
quant_config = {
"static_quant": {
"global": {
"weight_dtype": "int8",
"weight_sym": True,
"weight_granularity": "per_tensor",
"act_dtype": "int8",
"act_sym": True,
"act_granularity": "per_tensor",
},
"local": {
"conv1": {
"weight_dtype": "fp32",
"act_dtype": "fp32",
}
},
}
}
config = StaticQuantConfig.from_dict(quant_config)
```
2. Example of using `set_local`
```python
quant_config = StaticQuantConfig()
conv2d_config = StaticQuantConfig(
weight_dtype="fp32",
act_dtype="fp32",
)
quant_config.set_local("conv1", conv2d_config)
```

## Examples

Users can also refer to [examples](https://github.com/intel/neural-compressor/blob/master/examples/3.x_api/tensorflow) on how to quantize a TensorFlow model with INC 3x API.
52 changes: 52 additions & 0 deletions docs/3x/TF_SQ.md
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# Smooth Quant

1. [Introduction](#introduction)
2. [Usage](#usage)
2.1 [Using a Fixed alpha](#using-a-fixed-alpha)
2.2 [Determining the alpha through auto-tuning](#determining-the-alpha-through-auto-tuning)
3. [Examples](#examples)


## Introduction

Quantization is a common compression operation to reduce memory and accelerate inference by converting the floating point matrix to an integer matrix. For large language models (LLMs) with gigantic parameters, the systematic outliers make quantification of activations difficult. [SmoothQuant](https://arxiv.org/abs/2211.10438), a training free post-training quantization (PTQ) solution, offline migrates this difficulty from activations to weights with a mathematically equivalent transformation.

Please refer to the document of [Smooth Quant](../quantization.md/#smooth-quant) for detailed fundamental knowledge.


## Usage
There are two ways to apply smooth quantization: 1) using a fixed `alpha` for the entire model or 2) determining the `alpha` through auto-tuning.

### Using a Fixed `alpha`
To set a fixed alpha for the entire model, users can follow this example:

```python
from neural_compressor.tensorflow import SmoothQuantConfig, StaticQuantConfig

quant_config = [SmoothQuantConfig(alpha=0.5), StaticQuantConfig()]
q_model = quantize_model(output_graph_def, [sq_config, static_config], calib_dataloader)
```
The `SmoothQuantConfig` should be combined with `StaticQuantConfig` in a list because we still need to insert QDQ and apply pattern fusion after the smoothing process.


### Determining the `alpha` through auto-tuning
Users can search for the best `alpha` for the entire model.The tuning process looks for the optimal `alpha` value from a list of `alpha` values provided by the user.

Here is an example:

```python
from neural_compressor.tensorflow import StaticQuantConfig, SmoothQuantConfig

custom_tune_config = TuningConfig(config_set=[SmoothQuantConfig(alpha=[0.5, 0.6, 0.7]), StaticQuantConfig()])
best_model = autotune(
model="fp32_model",
tune_config=custom_tune_config,
eval_fn=eval_fn_wrapper,
calib_dataloader=calib_dataloader,
)
```
> Please note that, it may a considerable amount of time as the tuning process applies each `alpha` to the entire model and uses the evaluation result on the entire dataset as the metric to determine the best `alpha`.
## Examples

Users can also refer to [examples](https://github.com/intel/neural-compressor/blob/master/examples/3.x_api/tensorflow/nlp/large_language_models\quantization\ptq\smoothquant) on how to apply smooth quant to a TensorFlow model with INC 3x API.
206 changes: 206 additions & 0 deletions docs/3x/TensorFlow.md
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TensorFlow
===============


1. [Introduction](#introduction)
2. [API for TensorFlow](#api-for-tensorflow)
3. [Support Matrix](#support-matrix)
3.1 [Quantization Scheme](#quantization-scheme)
3.2 [Quantization Approaches](#quantization-approaches)
3.3 [Backend and Device](#backend-and-device)

## Introduction

<div align="center">
<img src="https://www.tensorflow.org/images/tf_logo_horizontal.png">
</div>

[TensorFlow](https://www.tensorflow.org/) is an end-to-end open source platform for machine learning. It has a comprehensive, flexible ecosystem of [tools](https://www.tensorflow.org/resources/tools), [libraries](https://www.tensorflow.org/resources/libraries-extensions), and [community](https://www.tensorflow.org/community) resources that lets researchers push the state-of-the-art in ML and developers easily build and deploy ML-powered applications. It provides stable [Python](https://www.tensorflow.org/api_docs/python) and [C++](https://www.tensorflow.org/api_docs/cc) APIs, as well as a non-guaranteed backward compatible API for [other languages](https://www.tensorflow.org/api_docs).

Keras is a multi-backend deep learning framework , supporting JAX, TensorFlow, and PyTorch. It serves as a dependency of TensorFlow, providing high-level API. Effortlessly build and train models for computer vision, natural language processing, audio processing, timeseries forecasting, recommender systems, etc.



## API for TensorFlow

Intel(R) Neural Compressor provides `quantize_model` and `autotune` as main interfaces for supported algorithms on TensorFlow framework.


**quantize_model**

The design philosophy of the `quantize_model` interface is easy-of-use. With minimal parameters requirement, including `model`, `quant_config`, `calib_dataloader` and `calib_iteration`, it offers a straightforward choice of quantizing TF model in one-shot.

```python
def quantize_model(
model: Union[str, tf.keras.Model, BaseModel],
quant_config: Union[BaseConfig, list],
calib_dataloader: Callable = None,
calib_iteration: int = 100,
):
```
`model` should be a string of the model's location, the object of Keras model or INC TF model wrapper class.

`quant_config` is either the `StaticQuantConfig` object or a list contains `SmoothQuantConfig` and `StaticQuantConfig` to indicate what algorithm should be used and what specific quantization rules should be applied.

`calib_dataloader` is used to load the data samples for calibration phase. In most cases, it could be the partial samples of the evaluation dataset.

`calib_iteration` is used to decide how many iterations the calibration process will be run.

Here is a simple example of using `quantize_model` interface with a dummy calibration dataloader and the default `StaticQuantConfig`:
```python
from neural_compressor.tensorflow import StaticQuantConfig, quantize_model
from neural_compressor.tensorflow.utils import DummyDataset

dataset = DummyDataset(shape=(100, 32, 32, 3), label=True)
calib_dataloader = MyDataLoader(dataset=dataset)
quant_config = StaticQuantConfig()

qmodel = quantize_model("fp32_model.pb", quant_config, calib_dataloader)
```
**autotune**

The `autotune` interface, on the other hand, provides greater flexibility and power. It's particularly useful when accuracy is a critical factor. If the initial quantization doesn't meet the tolerance of accuracy loss, `autotune` will iteratively try quantization rules according to the `tune_config`.

Just like `quantize_model`, `autotune` requires `model`, `calib_dataloader` and `calib_iteration`. And the `eval_fn`, `eval_args` are used to build evaluation process.



```python
def autotune(
model: Union[str, tf.keras.Model, BaseModel],
tune_config: TuningConfig,
eval_fn: Callable,
eval_args: Optional[Tuple[Any]] = None,
calib_dataloader: Callable = None,
calib_iteration: int = 100,
) -> Optional[BaseModel]:
```
`model` should be a string of the model's location, the object of Keras model or INC TF model wrapper class.

`tune_config` is the `TuningConfig` object which contains multiple quantization rules.

`eval_fn` is the evaluation function that measures the accuracy of a model.

`eval_args` is the supplemental arguments required by the defined evaluation function.

`calib_dataloader` is used to load the data samples for calibration phase. In most cases, it could be the partial samples of the evaluation dataset.

`calib_iteration` is used to decide how many iterations the calibration process will be run.

Here is a simple example of using `autotune` interface with different quantization rules defined by a list of `StaticQuantConfig`:
```python
from neural_compressor.common.base_tuning import TuningConfig
from neural_compressor.tensorflow import StaticQuantConfig, autotune

calib_dataloader = MyDataloader(dataset=Dataset())
custom_tune_config = TuningConfig(
config_set=[
StaticQuantConfig(weight_sym=True, act_sym=True),
StaticQuantConfig(weight_sym=False, act_sym=False),
]
)
best_model = autotune(
model="baseline_model",
tune_config=custom_tune_config,
eval_fn=eval_acc_fn,
calib_dataloader=calib_dataloader,
)
```

### Support Matrix

#### Quantization Scheme

| Framework | Backend Library | Symmetric Quantization | Asymmetric Quantization |
| :-------------- |:---------------:| ---------------:|---------------:|
| TensorFlow | [oneDNN](https://github.com/oneapi-src/oneDNN) | Activation (int8/uint8), Weight (int8) | - |
| Keras | [ITEX](https://github.com/intel/intel-extension-for-tensorflow) | Activation (int8/uint8), Weight (int8) | - |


+ Symmetric Quantization
+ int8: scale = 2 * max(abs(rmin), abs(rmax)) / (max(int8) - min(int8) - 1)
+ uint8: scale = max(rmin, rmax) / (max(uint8) - min(uint8))


+ oneDNN: [Lower Numerical Precision Deep Learning Inference and Training](https://software.intel.com/content/www/us/en/develop/articles/lower-numerical-precision-deep-learning-inference-and-training.html)

#### Quantization Approaches

The supported Quantization methods for TensorFlow and Keras are listed below:
<table class="center">
<thead>
<tr>
<th>Types</th>
<th>Quantization</th>
<th>Dataset Requirements</th>
<th>Framework</th>
<th>Backend</th>
</tr>
</thead>
<tbody>
<tr>
<td rowspan="2" align="center">Post-Training Static Quantization (PTQ)</td>
<td rowspan="2" align="center">weights and activations</td>
<td rowspan="2" align="center">calibration</td>
<td align="center">Keras</td>
<td align="center"><a href="https://github.com/intel/intel-extension-for-tensorflow">ITEX</a></td>
</tr>
<tr>
<td align="center">TensorFlow</td>
<td align="center"><a href="https://github.com/tensorflow/tensorflow">TensorFlow</a>/<a href="https://github.com/Intel-tensorflow/tensorflow">Intel TensorFlow</a></td>
</tr>
<tr>
<td rowspan="2" align="center">Smooth Quantization(SQ)</td>
<td rowspan="2" align="center">weights</td>
<td rowspan="2" align="center">calibration</td>
<td align="center">Tensorflow</td>
<td align="center"><a href="https://github.com/tensorflow/tensorflow">TensorFlow</a>/<a href="https://github.com/Intel-tensorflow/tensorflow">Intel TensorFlow</a></td>
</tr>
</tbody>
</table>
<br>
<br>

##### Post Training Static Quantization

The min/max range in weights and activations are collected offline on a so-called `calibration` dataset. This dataset should be able to represent the data distribution of those unseen inference dataset. The `calibration` process runs on the original fp32 model and dumps out all the tensor distributions for `Scale` and `ZeroPoint` calculations. Usually preparing 100 samples are enough for calibration.

Refer to the [PTQ Guide](./TF_Quant.md) for detailed information.

##### Smooth Quantization

Smooth Quantization (SQ) is an advanced quantization technique designed to optimize model performance while maintaining high accuracy. Unlike traditional quantization methods that can lead to significant accuracy loss, SQ focuses on a more refined approach by taking a balance between the scale of activations and weights.

Refer to the [SQ Guide](./TF_SQ.md) for detailed information.

#### Backend and Device
Intel(R) Neural Compressor supports TF GPU with [ITEX-XPU](https://github.com/intel/intel-extension-for-tensorflow). We will automatically run model on GPU by checking if it has been installed.

<table class="center">
<thead>
<tr>
<th>Framework</th>
<th>Backend</th>
<th>Backend Library</th>
<th>Backend Value</th>
<th>Support Device(cpu as default)</th>
</tr>
</thead>
<tbody>
<tr>
<td rowspan="2" align="left">TensorFlow</td>
<td align="left">TensorFlow</td>
<td align="left">OneDNN</td>
<td align="left">"default"</td>
<td align="left">cpu</td>
</tr>
<tr>
<td align="left">ITEX</td>
<td align="left">OneDNN</td>
<td align="left">"itex"</td>
<td align="left">cpu | gpu</td>
</tr>
</tbody>
</table>
<br>
<br>
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