add trigger example2

Jetson/Jetvariety/external_trigger/arducam_external_trigger_demo2.py

@@ -0,0 +1,113 @@
+import cv2
+import numpy as np
+from datetime import datetime
+import array
+import fcntl
+import os
+import argparse
+import time
+from utils import ArducamUtils
+
+def resize(frame, dst_width):
+    width = frame.shape[1]
+    height = frame.shape[0]
+    scale = dst_width / width
+    return cv2.resize(frame, (int(scale * width), int(scale * height)))
+
+def display(cap, arducam_utils, device_num):
+    counter = 0
+    frame_count = 0
+    start_time = datetime.now()
+    cv2.namedWindow("Arducam")
+    start = time.time()
+    while True:
+        ret, frame = cap.read()
+        if ret:
+            counter += 1
+
+            frame = arducam_utils.convert(frame)
+
+            frame = resize(frame, 640.0)
+            # frame = cv2.rotate(frame, cv2.ROTATE_180)
+            # display
+            cv2.imshow("Arducam", frame)
+            frame_count += 1
+        ret = cv2.waitKey(10)
+        # press 'q' to exit.
+        if ret == ord('q'):
+            break
+
+        if time.time() - start >= 1:
+            print("fps: {}".format(frame_count))
+            start = time.time()
+            frame_count = 0 
+
+    end_time = datetime.now()
+    elapsed_time = end_time - start_time
+    avgtime = elapsed_time.total_seconds() / counter
+    print ("Average time between frames: " + str(avgtime))
+    print ("Average FPS: " + str(1/avgtime))
+
+
+def fourcc(a, b, c, d):
+    return ord(a) | (ord(b) << 8) | (ord(c) << 16) | (ord(d) << 24)
+
+def pixelformat(string):
+    if len(string) != 3 and len(string) != 4:
+        msg = "{} is not a pixel format".format(string)
+        raise argparse.ArgumentTypeError(msg)
+    if len(string) == 3:
+        return fourcc(string[0], string[1], string[2], ' ')
+    else:
+        return fourcc(string[0], string[1], string[2], string[3])
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(description='Arducam Jetson Nano MIPI Camera Sensor.')
+
+    parser.add_argument('-d', '--device', default=0, type=int, nargs='?',
+                        help='/dev/videoX default is 0')
+    parser.add_argument('-f', '--pixelformat', type=pixelformat,
+                        help="set pixelformat")
+    parser.add_argument('--width', type=lambda x: int(x,0),
+                        help="set width of image")
+    parser.add_argument('--height', type=lambda x: int(x,0),
+                        help="set height of image")
+
+    args = parser.parse_args()
+
+    # open camera
+    cap = cv2.VideoCapture(args.device, cv2.CAP_V4L2)
+    # set pixel format
+    # cap.set(cv2.CAP_PROP_FOURCC, cv2.VideoWriter_fourcc('Y', '1', '6', ' '))
+
+    if args.pixelformat != None:
+        if not cap.set(cv2.CAP_PROP_FOURCC, args.pixelformat):
+            print("Failed to set pixel format.")
+
+    arducam_utils = ArducamUtils(args.device)
+    # turn off RGB conversion
+    if arducam_utils.convert2rgb == 0:
+        cap.set(cv2.CAP_PROP_CONVERT_RGB, arducam_utils.convert2rgb)
+    cap.set(cv2.CAP_PROP_BUFFERSIZE, 4)
+    # set width
+    if args.width != None:
+        cap.set(cv2.CAP_PROP_FRAME_WIDTH, args.width)
+    # set height
+    if args.height != None:
+        cap.set(cv2.CAP_PROP_FRAME_HEIGHT, args.height)
+    cap.grab()
+    time.sleep(1)
+    os.system("v4l2-ctl -d {} -c trigger_mode=1".format(args.device))
+    os.system("v4l2-ctl -d {} -c frame_timeout=10000".format(args.device))
+    cap.grab()
+
+    # After the above operation, there are still two frames of data in the buffer, 
+    # and one frame can be read out every time one frame is triggered.Therefore, 
+    # there is a two-frame delay from triggering to reading the image.
+    #　The first two frames are not the triggered image.
+
+    # begin display
+    display(cap, arducam_utils, args.device)
+
+    # release camera
+    cap.release()