Request to Increase Data Acquisition Rate for Hands

[ark338]

Hello,

Thank you for the great work done previously!

I encountered an issue while using this project. The data acquisition rate for both hands from Vision Pro is 30Hz, which is insufficient for precise control. Is it possible to increase the reading frequency?

Thank you very much.

[Hao-Starrr]

@ark338 I have same questions. Do you solve it?

[Hao-Starrr]

Update: I measured the stream frequency. It receives data at 60-70hz. But the different data is received at about 30hz.

[LufanM]

I have a similar problem. How can I optimize the parameters of the gRPC protocol to reduce frame loss and stuttering during communication?

[younghyopark]

Hi @LufanM @Hao-Starrr @ark338 ,

With the recently updated app, I'm getting

Results:
Duration: 10.00 seconds
Total Messages Received: 1391
Unique Messages Received: 904
Average Message Rate: 139.04 Hz
Average Unique Data Rate: 90.36 Hz

which the 90Hz cap is coming from ARKit's hand tracking acquisition rate rather than the gRPC side.

---

I've used this script:

import time
import argparse
from avp_stream import VisionProStreamer


class BenchmarkStreamer(VisionProStreamer):
    def __init__(self, *args, **kwargs):
        self.message_count = 0
        self.unique_count = 0
        self.last_position = None
        self.measuring = False
        super().__init__(*args, **kwargs)
        
    def _process_hand_update(self, hand_update, source="grpc"):
        super()._process_hand_update(hand_update, source)
        
        if not self.measuring:
            return
            
        self.message_count += 1
        
        current_pos = (
            hand_update.right_hand.wristMatrix.m03,
            hand_update.right_hand.wristMatrix.m13,
            hand_update.right_hand.wristMatrix.m23
        )
        
        if self.last_position != current_pos:
            self.unique_count += 1
            self.last_position = current_pos


def main():
    parser = argparse.ArgumentParser(description="Benchmark Hand Tracking Data Rate")
    parser.add_argument("--ip", type=str, required=True, help="Vision Pro IP address")
    parser.add_argument("--duration", type=float, default=10.0, help="Duration of the benchmark in seconds")
    args = parser.parse_args()

    print(f"Connecting to Vision Pro at {args.ip}...")
    streamer = BenchmarkStreamer(ip=args.ip, record=False)
    
        
    print(f"Collecting data for {args.duration} seconds...")
    streamer.measuring = True
    start_time = time.time()
    time.sleep(args.duration)
    streamer.measuring = False
    duration = time.time() - start_time
    
    print(f"\nResults:")
    print(f"Duration: {duration:.2f} seconds")
    print(f"Total Messages: {streamer.message_count}")
    print(f"Unique Messages: {streamer.unique_count}")
    print(f"Message Rate: {streamer.message_count / duration:.2f} Hz")
    print(f"Unique Data Rate: {streamer.unique_count / duration:.2f} Hz")

if __name__ == "__main__":
    main()