OpenMV Python

Python library and CLI for communicating with OpenMV cameras.

Installation

pip install openmv

CLI Usage

Examples

# Basic usage - stream video from camera
openmv --port /dev/ttyACM0

# Run a custom script
openmv --port /dev/ttyACM0 --script my_script.py

# Adjust display scale (default is 4x)
openmv --port /dev/ttyACM0 --scale 5

# Run throughput benchmark
openmv --port /dev/ttyACM0 --bench

# Load firmware symbols for profiler function names
openmv --port /dev/ttyACM0 --firmware build/firmware.elf

# Quiet mode (suppress script output)
openmv --port /dev/ttyACM0 --quiet

# Debug mode (verbose logging)
openmv --port /dev/ttyACM0 --debug

# Preview a custom data channel
openmv --port /dev/ttyACM0 --channel ticks

Options

Protocol Options

Keyboard Controls

Library Usage

from openmv import Camera

script = """
import csi, time

csi0 = csi.CSI()
csi0.reset()
csi0.pixformat(csi.RGB565)
csi0.framesize(csi.QVGA)
clock = time.clock()
while True:
    clock.tick()
    img = csi0.snapshot()
    print(clock.fps(), "FPS")
"""

# Connect to camera
with Camera('/dev/ttyACM0') as camera:
    # Stop running script (if any)
    camera.stop()

    # Execute script and enable streaming
    camera.exec(script)
    camera.streaming(True)

    # Read frames and output
    while True:
        if frame := camera.read_frame():
            print(f"Frame: {frame['width']}x{frame['height']}")

        if text := camera.read_stdout():
            print(text, end='')

Custom Channels

Custom channels allow bidirectional data exchange between the camera and host.

Camera-side script (MicroPython):

import time
import protocol

class TicksChannel:
    def size(self):
        return 10

    def read(self, offset, size):
        return f'{time.ticks_ms():010d}'

    def poll(self):
        return True

protocol.register(name='ticks', backend=TicksChannel())

Host-side (Python):

from openmv import Camera

with Camera('/dev/ttyACM0') as camera:
    camera.exec(script)

    while True:
        # Check if channel has data
        if camera.has_channel('ticks'):
            size = camera.channel_size('ticks')
            if size > 0:
                data = camera.channel_read('ticks', size)
                print(f"Ticks: {data.decode()}")

Quick Reference

Camera

from openmv import Camera

Camera(
    port,               # Serial port (e.g., '/dev/ttyACM0')
    baudrate=921600,    # Serial baudrate
    crc=True,           # Enable CRC validation
    seq=True,           # Enable sequence number validation
    ack=True,           # Enable packet acknowledgment
    events=True,        # Enable event notifications
    timeout=1.0,        # Protocol timeout in seconds
    max_retry=3,        # Maximum retries
    max_payload=4096,   # Maximum payload size
    drop_rate=0.0,      # Packet drop simulation (testing only)
)

Methods

Profiler Methods (if available)

Exceptions

API documentation

Full API documentation: docs/api.md

Requirements

• Python 3.8+
• pyserial >= 3.5
• numpy >= 1.20.0
• pygame >= 2.0.0
• pyelftools

License

MIT License - Copyright (c) 2025 OpenMV, LLC.