# Zero Shot Image Classification

## 任务描述

零样本图像分类：模型在基于图文对的预训练后，可以在给定任意图片与候选标签列表的情况下，完成对图像的分类，而无需任何微调。

[相关论文](https://arxiv.org/abs/2103.00020) Alec Radford, Jong Wook Kim, et al., Learning Transferable Visual Models From Natural Language Supervision, 2021.

## 已支持数据集性能

| model |                                   type                                   | datasets |                Top1-accuracy                 |      stage       |                                                                                          example                                                                                          |
|:-----:|:------------------------------------------------------------------------:|:--------:|:--------------------------------------------:|:----------------:|:-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------:|
| clip  | clip_vit_b_32 <br/>clip_vit_b_16<br/>clip_vit_l_14<br/>clip_vit_l_14@336 | Cifar100 | 57.24% <br/> 61.41% <br/> 69.67%<br/> 68.19% | eval<br/>predict | [link](../../examples/zero_shot_image_classification/clip_vit_b_32_eval_on_cifar100.sh) <br/> [link](../../examples/zero_shot_image_classification/clip_vit_b_32_predict_on_cifar100.sh) |

### [Cifar100](http://www.cs.toronto.edu/~kriz/cifar-100-python.tar.gz)

- 数据集大小：161M，共60000张图片，100个类别
    - 训练集：50000张图片
    - 测试集：10000张图片
- 数据格式：二进制文件

 ```bash
数据集目录格式
└─cifar-100-python
    ├─meta
    ├─test  
    └─train  
 ```

## 快速任务接口

- Trainer接口开启评估/推理：

```python
from mindformers import MindFormerBook
from mindformers.trainer import Trainer
from mindformers.tools.image_tools import load_image

# 显示Trainer的模型支持列表
MindFormerBook.show_trainer_support_model_list("zero_shot_image_classification")
# INFO - Trainer support model list for zero_shot_image_classification task is:
# INFO -    ['clip_vit_b_32', 'clip_vit_b_16', 'clip_vit_l_14', 'clip_vit_l_14@336']
# INFO - -------------------------------------

# 初始化trainer
trainer = Trainer(task='zero_shot_image_classification',
    model='clip_vit_b_32',
    eval_dataset='cifar-100-python'
)
img = load_image("https://ascend-repo-modelzoo.obs.cn-east-2."
          "myhuaweicloud.com/XFormer_for_mindspore/clip/sunflower.png")
trainer.evaluate()  #下载权重进行评估
# INFO - Top1 Accuracy=57.24%
trainer.predict(input_data=img)  #下载权重进行推理
# INFO - output result is saved at ./results.txt
```

- pipeline接口开启快速推理

```python
from mindformers import pipeline, MindFormerBook
from mindformers.tools.image_tools import load_image

# 显示pipeline支持的模型列表
MindFormerBook.show_pipeline_support_model_list("zero_shot_image_classification")
# INFO - Pipeline support model list for zero_shot_image_classification task is:
# INFO -    ['clip_vit_b_32', 'clip_vit_b_16', 'clip_vit_l_14', 'clip_vit_l_14@336']
# INFO - -------------------------------------

# pipeline初始化
classifier = pipeline("zero_shot_image_classification",
                      model="clip_vit_b_32"
                      candidate_labels=["sunflower", "tree", "dog", "cat", "toy"])
img = load_image("https://ascend-repo-modelzoo.obs.cn-east-2."
          "myhuaweicloud.com/XFormer_for_mindspore/clip/sunflower.png")
classifier(img)
# 输出
# [[{'score': 0.99995565, 'label': 'sunflower'}, {'score': 2.5318595e-05, 'label': 'toy'},
# {'score': 9.903885e-06, 'label': 'dog'}, {'score': 6.75336e-06, 'label': 'tree'},
# {'score': 2.396818e-06, 'label': 'cat'}]]
```