[Feature request] Linux named pipe for motion detection

[k1x0r]

Introduction

Currently it isn't possible to get the motion detection events from Majestic streamer from 3rd party applications. The solution of running a "motion-detect" example from Hi3516EV200 MPP alongside Majestic isn't possible, because of the implementation of the SDK. Having a 3rd-party app on the camera side would allow the user to send "motion detect" events to the server.

The suitable approach for this would be a linux pipe, because the implementation of sending "motion detect" event wouldn't depend on implementation in majestic. Analyzing such stream, a 3rd party app would send a request to the server, which will trigger the recording of the video on the server side.

Detailed design

The most straightforward approach is to create a pipe named e.g "/tmp/majestic_md" and send current motion detection status if it's changed. To keep the protocol simple, the pipe should output only '1' and '0' characters with the meaning: "Motion detection is present" and "Motion detection is absent".

A 'dummy' implementation for sending events to the pipe:

int main(int argc, char *argv[]) {
    signal(SIGPIPE, SIG_IGN); // Not to exit the app when the last reading process has been killed
    const char* pipeName = "/tmp/majestic_md";
    mkfifo(pipeName, 0777);                     
    int fd = open(pipeName, O_CREAT | O_WRONLY); 
    const char kOne = '1';
    const char kZero = '0';      
    for (int i = 0; i < 10000; i++) {         
       write(fd, &(i % 2 == 0 ? kZero : kOne), sizeof(char));
       usleep(1000);
    }
    close(fd);
    unlink(pipeName);
}

In order to test this sample, one should run the following command line: cat /tmp/majestic_md

And reading such pipe programmatically in blocking mode should also be also pretty straightforward:

int main(int argc, char *argv[]) {
  const char* file = "/tmp/majestic_md";
  int fd = open(file, O_RDONLY);
  if (fd < 0) return -1;
  char motionDetected;
  while (1) {
    ssize_t count = read(fd, &motionDetected, sizeof(char));
    if (count > 0) { 
        printf("Motion Detected: %c\r\n", motionDetected);
    } else {
        break;
    }
  }
  close(fd);
  unlink(file);
}

[flyrouter]

Please use md_detect param in /metrics setting

More params:

# HELP md_rects_recv_total Number of rectangles returned by HW MD algorithm.
# TYPE md_rects_recv_total counter
md_rects_recv_total 0
# HELP md_rects_acc_total Number of rectangles fit into ROI.
# TYPE md_rects_acc_total counter
md_rects_acc_total 0
# HELP md_status Motion detect activation status.
# TYPE md_status gauge
md_status 0

[flyrouter]

The request is opened again because it becomes relevant and overlaps with others.

[flyrouter]

In the new Majestic dated 2023.10.24

If motion detect is enabled (for Hisilion/Goke, Ingenic and Sigmastar), the first check is for an executable file: /etc/majestic_motion.sh

Then the following will be called: /etc/majestic_motion.sh 1163 0 400 275 &

The usage is: /etc/majestic_motion.sh [x coordinate] [y coordinate] [region width] [region height]

Example script:

#!/bin/sh

echo 0:[$0] 1:[$1] 2:[$2] 3:[$3] 4:[$4]

Final diagnosis

20:37:02  <SED_IVE_DETCTOR> [  motion] motion_update@155             Motion detected: [1163x0] -> [690x475]
20:37:02  <SED_IVE_DETCTOR> [   tools] motion_event@615              Execute motion script: /etc/majestic_motion.sh
0:[/etc/majestic_motion.sh] 1:[1163] 2:[0] 3:[690] 4:[475]

[flyrouter]

Updated the following 2023.11.02

• script name: /etc/motion_detect.sh
• script usage: [object count] [x coordinate] [y coordinate] [region width] [region height]