3D-QAE

This is the official repository for the project "3D-QAE: A Fully Quantum Auto-Encoder for 3D Shapes". This project introduces the first quantum auto-encoder for 3D point sets, using data normalisation techniques and by introducing auxiliary values to combat the input and output restrictions of quantum circuits. For more details, refer to the project page.

The codebase is implemented using the Pytorch interface in Pennylane, for noise-less quantum simulation on the CPU.

Create environment

The code can be run by creating an environment torch using the given environment.yml file (or installing the requirements using pip).

We recommend using miniconda to set up the environment:

conda env create -f environment.yml

This conda environment can then be activate with conda activate torch

Dataset

Downloading the data

The data can be downloaded from the AMASS website and saved in a folder named as Amass_files. For this project we used the CMU Graphics Lab Motion Capture Database downloaded as .npz files.

Downloading the SMPLify-X model

To extract the joints from the motion capture data, we need SMPLify-X models which can be downloaded from their website. The path for this downloaded model needs to be updated inside the find_joints.py file in the bm_fname variable.

Processing AMASS data

Next, we extract joints from the AMASS data files . To do this activate the torch environment and run,

python3 find_joints.py

Training and Testing

After the dataset preparation, the quantum models can be trained by running the given python files.

• To train with a repeat architecture, run: python repeat_architecture.py --config <path_to_config_file>
• To train with an identity architecture, run: python identity_architecture.py --config <path_to_config_file>

The config file allows us to set the training options.

• The parameter initialisation for the model can be set as random or identity in the params_initialization argument. For example, to set the parameter initialisation as random, run: python <filename.py> --config <path_to_config_file> --params_initialization random
• The basic building blocks of the quantum circuit can be chosen out of "A", "B", "C" or "D" in the basic_block argument. For example, the basic_block "B" can be chosen, by running: python <filename.py> --config <path_to_config_file> --basic_block B.
• The number of training epochs can be set using num_epochs argument.
• The number of blocks each in the encoder/decoder of the model is set using num_reps argument.
• The encoder or decoder can be replaced by classical fully-connected layers to build a hybrid model by setting the corresponding arguments. For example to build a hybrid model with classical encoder and quantum decoder, run: python <filename.py> --config <path_to_config_file> --classical_encoder True

Best Results

Evaluating the different combinations, we observe that the basic block "B" alongwith the "repeat" architecture and "identity" parameter initialisation scheme works the best. Using 8 blocks each in the encoder and decoder, we report a mean euclidean distance of 10.86 cm.

Citation

@InProceedings{Rathi2023, 
    author={Rathi, Lakshika  and Tretschk, Edith and Theobalt, Christian and Dabral, Rishabh  and Golyanik, Vladislav}, 
    title={{3D-QAE}: Fully Quantum Auto-Encoding of 3D Point Clouds}, 
    booktitle={The British Machine Vision Conference (BMVC)}, 
    year={2023} 
}