Example: 01-Camera/03-Event-Cameras/02-Genx320/genx320_event_mode_set_stc.py

# 本作品采用MIT许可证授权。
# Copyright (c) 2026 OpenMV LLC. All rights reserved.
# https://github.com/openmv/openmv/blob/master/LICENSE
#
# This example shows off using the genx320's spatio-temporal contrast (STC) filter.
# Includes examples on how to use STC mode, Trail mode, and STC + Trail mode

import csi
import time
# https://micropython-ulab.readthedocs.io/en/latest/index.html
from ulab import numpy as np
import image

# Surface to draw the histogram image on.
img = image.Image(320, 320, image.GRAYSCALE)

# Stores camera events # Shape: (EVT_res, 6) where EVT_res is the event resolution
# EVT_res: must be a power of two between 1024 and 65536.
# Columns:
# [0] Event type
# [1] Seconds timestamp
# [2] Milliseconds timestamp
# [3] Microseconds timestamp
# [4] X coordinate 0 to 319 for GENX320
# [5] Y coordinate 0 to 319 for GENX320
events = np.zeros((8192, 6), dtype=np.uint16)

# Initialize the sensor.
csi0 = csi.CSI(cid=csi.GENX320)
csi0.reset()
csi0.ioctl(csi.IOCTL_GENX320_SET_MODE, csi.GENX320_MODE_EVENT, events.shape[0])

# Sets the GENX320's STC filter to one of three available modes:
# GENX320_STC_DISABLE      - Disable the STC filter entirely
#                          - Parameter(s): None
# GENX320_STC_ONLY         - Mode that retains second event of an event burst from contrast edge
#                          - Parameter(s): stc_threshold
# GENX320_STC_TRAIL_ONLY   - Mode that retains first event of an event burst from contrast edge
#                          - Parameter(s): trail_threshold
# GENX320_STC_TRAIL        - Mode that retains multiple events of an event burst from a contrast edge
#                          - Parameters(s): stc_threshold, trail_threshold
stc_threshold = 1    # 1 ms threshold
trail_threshold = 2  # 2 ms threshold
csi0.ioctl(csi.IOCTL_GENX320_SET_STC, csi.GENX320_STC_TRAIL, stc_threshold, trail_threshold)
# Disable STC filter
# csi0.ioctl(csi.IOCTL_GENX320_SET_STC, csi.GENX320_STC_DISABLE)

clock = time.clock()

# Enable FIFO buffering to prevent event drops during processing.
# Triple-buffer mode prioritizes the latest data, while FIFO mode
# (buffer count > 3) queues events instead, avoiding drops if the
# processor keeps up, but possibly processing older data.
FIFO_DEPTH = 10
csi0.framebuffers(FIFO_DEPTH)

while True:
    clock.tick()

    # Reads up to 8192 events from the camera.
    # Returns the number of valid events (0-8192) or a negative error code.
    # Note that old events in the buffer are not cleared to save CPU time.
    event_count = csi0.ioctl(csi.IOCTL_GENX320_READ_EVENTS, events)

    # Render events into a histogram image.
    # If clear=True, the image is reset to "brightness" before drawing.
    # For each PIX_ON_EVENT, add "contrast" to the bin value;
    # for each PIX_OFF_EVENT, subtract it and clamp to [0, 255].
    # If clear=False, histogram accumulates over multiple calls.
    img.draw_event_histogram(events[:event_count], clear=True, brightness=128, contrast=64)

    # Push the image to the jpeg buffer for the IDE to pull and display.
    # The IDE pulls frames off the camera at a much lower rate than the
    # onboard camera frame rate printed below.
    img.flush()

    print(event_count, clock.fps())