GRIT: Faster and Better Image captioning Transformer (ECCV 2022)

This is the code implementation for the paper titled: "GRIT: Faster and Better Image-captioning Transformer Using Dual Visual Features" (Accepted to ECCV 2022) [Arxiv].

Introduction

This paper proposes a Transformer neural architecture, dubbed GRIT (Grid- and Region-based Image captioning Transformer), that effectively utilizes the two visual features to generate better captions. GRIT replaces the CNN-based detector employed in previous methods with a DETR-based one, making it computationally faster.

Model Zoo

Installation

Requirements

• Python >= 3.9, CUDA >= 11.3

• PyTorch >= 1.12.0, torchvision >= 0.6.1

• Other packages: pycocotools, tensorboard, tqdm, h5py, nltk, einops, hydra, spacy, and timm

• First, clone the repository locally:

  git clone https://github.com/davidnvq/grit.git
  cd grit

• Then, create an environment and install PyTorch and torchvision:

  conda create -n grit python=3.9
  conda activate grit
  pip install torch torchvision --extra-index-url https://download.pytorch.org/whl/cu113
  # ^ if the CUDA version is not compatible with your system; visit pytorch.org for compatible matches.

• Install other requirements:

  pip install -r requirements.txt
  python -m spacy download en

• Install Deformable Attention:

  cd models/ops/
  python setup.py build develop
  python test.py

Usage

Data preparation

Download and extract COCO 2014 for image captioning including train, val, and test images with annotations from http://cocodataset.org. We expect the directory structure to be the following:

path/to/coco_caption/
├── annotations/  # annotation json files and Karapthy files
├── train2014/    # train images
├── val2014/      # val images
└── test2014/     # test images

• Copy the files in data/ to the above annotations folder. It includes vocab.json and some files containing Karapthy ids.

Training

The model is trained with default settings in the configurations file in configs/caption/coco_config.yaml: The training process takes around 16 hours on a machine with 8 A100 GPU. We also provide the code for extracting pretrained features (freezed object detector), which will speed up the training significantly.

• With default configurations (e.g., 'parallel Attention', pretrained detectors on VG or 4DS, etc):

  
  export DATA_ROOT=path/to/coco_dataset
  # with pretrained object detector on 4 datasets
  python train_caption.py exp.name=caption_4ds model.detector.checkpoint=4ds_detector_path

with pretrained object detector on Visual Genome

python train_caption.py exp.name=caption_4ds model.detector.checkpoint=vg_detector_path

<!-- * **More configurations will be added here for obtaining ablation results**. -->
* To freeze the backbone and detector, we can extract the region features and initial grid features first, saving it to `dataset.hdf5_path` in the config file.

**Noted that: this additional strategy will only achieve about 134 CIDEr (as reported by some researchers). To obtain 139.2 CIDEr, please train the model with freezed backbone/detector (in Pytorch, using `if 'backbone'/'detector' in n: p.requires_grad = False`) with image augmentation at every iteration. It means that we read and process every image during training rather than loading `extracted features` from hdf5.**

Then we can run the following script to train the model:
```shell
export DATA_ROOT=path/to/coco_dataset
# with pretrained object detector on 4 datasets
python train_caption.py exp.name=caption_4ds model.detector.checkpoint=4ds_detector_path \
optimizer.freezing_xe_epochs=10 \
optimizer.freezing_sc_epochs=10 \
optimizer.finetune_xe_epochs=0 \
optimizer.finetune_sc_epochs=0 \
optimizer.freeze_backbone=True \
optimizer.freeze_detector=True

Evaluation

The evaluation will be run on a single GPU.

• Evaluation on Karapthy splits:

  
  export DATA_ROOT=path/to/coco_caption
  # evaluate on the validation split
  python eval_caption.py +split='valid' exp.checkpoint=path_to_caption_checkpoint

evaluate on the test split

python eval_caption.py +split='test' exp.checkpoint=path_to_caption_checkpoint

* Evaluation on the **online splits**:
```shell
export DATA_ROOT=path/to/coco_caption
# evaluate on the validation split
python eval_caption_online.py +split='valid' exp.checkpoint=path_to_caption_checkpoint

# evaluate on the test split
python eval_caption_online.py +split='test' exp.checkpoint=path_to_caption_checkpoint

Inference on RGB Image

• Perform Inference for a single image using the script inference_caption.py:

  python inference_caption.py +img_path='notebooks/COCO_val2014_000000000772.jpg' \
  +vocab_path='data/vocab.json' \
  exp.checkpoint='path_to_caption_checkpoint'

• Perform Inference for a single image using the Jupyter notebook notebooks/Inference.ipynb

  
  # Require installing Jupyter(lab)
  pip install jupyterlab

cd notebooks

Open jupyter notebook

jupyter lab

### Finetune / Retrain GRIT on your own Dataset
We provide an example of how we finetune GRIT on the custom dataset (here is Vietnamese Image Captioning). 
Interestingly, the result shows that the GRIT checkpoint on COCO (English) benefits another language captioning task.
You may need to modify a few files only. For exapmle, we prepare 3 files in the [vicap branch](https://github.com/davidnvq/grit/tree/vicap):
* https://github.com/davidnvq/grit/blob/vicap/train_vicap.py
* https://github.com/davidnvq/grit/blob/vicap/vicap_dataset.py
* https://github.com/davidnvq/grit/blob/vicap/configs/caption/vicap_config.yaml

## Citation
If you find this code useful, please kindly cite the paper with the following bibtex:
```bibtex
@inproceedings{nguyen2022grit,
  title={Grit: Faster and better image captioning transformer using dual visual features},
  author={Nguyen, Van-Quang and Suganuma, Masanori and Okatani, Takayuki},
  booktitle={Computer Vision--ECCV 2022: 17th European Conference, Tel Aviv, Israel, October 23--27, 2022, Proceedings, Part XXXVI},
  pages={167--184},
  year={2022},
  organization={Springer}
}

Acknowledgement

We have inherited several open source projects into ours: i) implmentation of Swin Transformer, ii) implementation of Deformable DETR, and iii) implementation of image captioning base from M2-Transformer. We thank the authors of these open source projects.