library_name: pytorch
license: apache-2.0
pipeline_tag: object-detection
tags:
- real_time
- android
MediaPipe-Hand-Detection: Optimized for Mobile Deployment
Real-time hand detection optimized for mobile and edge
The MediaPipe Hand Landmark Detector is a machine learning pipeline that predicts bounding boxes and pose skeletons of hands in an image.
This model is an implementation of MediaPipe-Hand-Detection found here. This repository provides scripts to run MediaPipe-Hand-Detection on Qualcomm® devices. More details on model performance across various devices, can be found here.
Model Details
- Model Type: Object detection
- Model Stats:
- Input resolution: 256x256
- Number of parameters (MediaPipeHandDetector): 1.76M
- Model size (MediaPipeHandDetector): 6.76 MB
- Number of parameters (MediaPipeHandLandmarkDetector): 2.01M
- Model size (MediaPipeHandLandmarkDetector): 7.71 MB
Device | Chipset | Target Runtime | Inference Time (ms) | Peak Memory Range (MB) | Precision | Primary Compute Unit | Target Model |
---|---|---|---|---|---|---|---|
Samsung Galaxy S23 Ultra (Android 13) | Snapdragon® 8 Gen 2 | TFLite | 0.762 ms | 0 - 3 MB | FP16 | NPU | MediaPipeHandDetector.tflite |
Samsung Galaxy S23 Ultra (Android 13) | Snapdragon® 8 Gen 2 | TFLite | 1.017 ms | 0 - 2 MB | FP16 | NPU | MediaPipeHandLandmarkDetector.tflite |
Samsung Galaxy S23 Ultra (Android 13) | Snapdragon® 8 Gen 2 | QNN Model Library | 0.82 ms | 1 - 6 MB | FP16 | NPU | MediaPipeHandDetector.so |
Samsung Galaxy S23 Ultra (Android 13) | Snapdragon® 8 Gen 2 | QNN Model Library | 1.088 ms | 1 - 51 MB | FP16 | NPU | MediaPipeHandLandmarkDetector.so |
Installation
This model can be installed as a Python package via pip.
pip install "qai-hub-models[mediapipe_hand]"
Configure Qualcomm® AI Hub to run this model on a cloud-hosted device
Sign-in to Qualcomm® AI Hub with your
Qualcomm® ID. Once signed in navigate to Account -> Settings -> API Token
.
With this API token, you can configure your client to run models on the cloud hosted devices.
qai-hub configure --api_token API_TOKEN
Navigate to docs for more information.
Demo off target
The package contains a simple end-to-end demo that downloads pre-trained weights and runs this model on a sample input.
python -m qai_hub_models.models.mediapipe_hand.demo
The above demo runs a reference implementation of pre-processing, model inference, and post processing.
NOTE: If you want running in a Jupyter Notebook or Google Colab like environment, please add the following to your cell (instead of the above).
%run -m qai_hub_models.models.mediapipe_hand.demo
Run model on a cloud-hosted device
In addition to the demo, you can also run the model on a cloud-hosted Qualcomm® device. This script does the following:
- Performance check on-device on a cloud-hosted device
- Downloads compiled assets that can be deployed on-device for Android.
- Accuracy check between PyTorch and on-device outputs.
python -m qai_hub_models.models.mediapipe_hand.export
Profile Job summary of MediaPipeHandDetector
--------------------------------------------------
Device: Samsung Galaxy S23 Ultra (13)
Estimated Inference Time: 0.76 ms
Estimated Peak Memory Range: 0.01-3.13 MB
Compute Units: NPU (151) | Total (151)
Profile Job summary of MediaPipeHandLandmarkDetector
--------------------------------------------------
Device: Samsung Galaxy S23 Ultra (13)
Estimated Inference Time: 1.02 ms
Estimated Peak Memory Range: 0.02-2.30 MB
Compute Units: NPU (158) | Total (158)
Profile Job summary of MediaPipeHandDetector
--------------------------------------------------
Device: Samsung Galaxy S23 Ultra (13)
Estimated Inference Time: 0.82 ms
Estimated Peak Memory Range: 0.77-5.97 MB
Compute Units: NPU (196) | Total (196)
Profile Job summary of MediaPipeHandLandmarkDetector
--------------------------------------------------
Device: Samsung Galaxy S23 Ultra (13)
Estimated Inference Time: 1.09 ms
Estimated Peak Memory Range: 0.55-51.09 MB
Compute Units: NPU (209) | Total (209)
How does this work?
This export script leverages Qualcomm® AI Hub to optimize, validate, and deploy this model on-device. Lets go through each step below in detail:
Step 1: Compile model for on-device deployment
To compile a PyTorch model for on-device deployment, we first trace the model
in memory using the jit.trace
and then call the submit_compile_job
API.
import torch
import qai_hub as hub
from qai_hub_models.models.mediapipe_hand import Model
# Load the model
torch_model = Model.from_pretrained()
torch_model.eval()
# Device
device = hub.Device("Samsung Galaxy S23")
# Trace model
input_shape = torch_model.get_input_spec()
sample_inputs = torch_model.sample_inputs()
pt_model = torch.jit.trace(torch_model, [torch.tensor(data[0]) for _, data in sample_inputs.items()])
# Compile model on a specific device
compile_job = hub.submit_compile_job(
model=pt_model,
device=device,
input_specs=torch_model.get_input_spec(),
)
# Get target model to run on-device
target_model = compile_job.get_target_model()
Step 2: Performance profiling on cloud-hosted device
After compiling models from step 1. Models can be profiled model on-device using the
target_model
. Note that this scripts runs the model on a device automatically
provisioned in the cloud. Once the job is submitted, you can navigate to a
provided job URL to view a variety of on-device performance metrics.
profile_job = hub.submit_profile_job(
model=target_model,
device=device,
)
Step 3: Verify on-device accuracy
To verify the accuracy of the model on-device, you can run on-device inference on sample input data on the same cloud hosted device.
input_data = torch_model.sample_inputs()
inference_job = hub.submit_inference_job(
model=target_model,
device=device,
inputs=input_data,
)
on_device_output = inference_job.download_output_data()
With the output of the model, you can compute like PSNR, relative errors or spot check the output with expected output.
Note: This on-device profiling and inference requires access to Qualcomm® AI Hub. Sign up for access.
Deploying compiled model to Android
The models can be deployed using multiple runtimes:
TensorFlow Lite (
.tflite
export): This tutorial provides a guide to deploy the .tflite model in an Android application.QNN (
.so
export ): This sample app provides instructions on how to use the.so
shared library in an Android application.
View on Qualcomm® AI Hub
Get more details on MediaPipe-Hand-Detection's performance across various devices here. Explore all available models on Qualcomm® AI Hub
License
- The license for the original implementation of MediaPipe-Hand-Detection can be found here.
- The license for the compiled assets for on-device deployment can be found here.
References
Community
- Join our AI Hub Slack community to collaborate, post questions and learn more about on-device AI.
- For questions or feedback please reach out to us.