merlot

MERLOT: Multimodal Neural Script Knowledge Models

MERLOT is a model for learning what we are calling "neural script knowledge" -- representations about what is going on in videos, spanning multiple video frames with associated captions.

Visit our project page at rowanzellers.com/merlot, or read the full paper to learn more.

What's here

We are releasing the following:

• Code for the MERLOT model (in model/, with data processing in data/
• Code for running MERLOT over visual story ordering.

We plan to release:

• Information about the videos used in this work
• Code for adapting the model to other tasks (not strictly needed, but just to make things easier)

This is somewhat ongoing -- we hope to make it somewhat easier to adapt MERLOT to other tasks, please follow if interested!

Enviroment and setup

There are two different ways of running MERLOT right now

• Pretraining on videos This requires a TPU pod.
• Finetuning on downstream tasks We did this on TPU v3-8 machines. You can in theory do this on GPUs, however, this isn't tested or officially supported right now.
• Zero-shot visual-story ordering I have code for this on a TPU, but you should be able to do this on a GPU too.

conda create --name merlot python=3.7 && conda activate merlot
conda install -y python=3.7 tqdm numpy pyyaml scipy ipython cython typing h5py pandas

# If running on GPU
pip install tensorflow-gpu==1.15.5
# If running on TPU
pip install tensorflow==1.15.5

pip install --upgrade google-api-python-client oauth2client boto3 cloud-tpu-profiler regex opencv-python-headless Pillow seaborn
pip install numpy==1.17.0

Pretraining from scratch

This requires a large TPU pod for data-parallelism.

• First, you'll need to get a bunch of training data in "tfrecord" format -- see data processing in data/ for that. You'll then need to adjust the configuration of model/configs/merlot.yaml accordingly. You'll also need to add in your output path (where you want your newly pretrained model to be saved).
• Next, in the model directory, run python train.py configs/merlot.yaml

Finetuning on downstream tasks

• We used the configuration model/merlot.yaml and the checkpoint at gs://merlot/checkpoint_4segments/ for downstream task finetuning. This is slightly different than the checkpoint we used for story unshuffling (that we had to adapt to account for the 5 frame-caption segments for that task), but both should work.
• Actual finetuning code TBD -- you just create a MerlotModel model/modeling.py, set up your finetuning task (usually involving an additional output layer), and finetune.

Bibtex

@article{zellersluhessel2021merlot,
    title={MERLOT: Multimodal Neural Script Knowledge Models},
    author={Zellers, Rowan and Lu, Ximing and Hessel, Jack and Yu, Youngjae and Park, Jae Sung and Cao, Jize and Farhadi, Ali and Choi, Yejin},
    journal={arXiv preprint arXiv:2106.02636},
    year={2021}
}