Multi camera system operation

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Recording

Example for 2 cameras (2 X-Cams) - list comma-separated addresses in the GET line:

http://192.168.0.39/multicam/?ip=192.168.0.39,192.168.0.38
  • tests button to get some diagnostics
  • record button - starts recording on raw paritions (camera internal)
  • snapshot button - saves a zip archive to host pc

Howto

Basic

  1. Power on
  2. Refresh multicam gui to get camogm started
  3. Record-button the recording will be started from the Current LBA (in /mnt/sda1/camogm.disk)

Start from the beginning of raw partition

  1. Power on
  2. Remove /mnt/sda1/camogm.disk on each camera (a new one is created by camogm on recording start)
  3. Refresh multicam gui to get camogm started
  4. Record-button

Note: Steps 2 and 3 can be swapped. Camogms will recreate camogm.disks on recording start. The free space in the multicam gui will also update to correct value on recording start.


Download footage

  • /dev/sda1 - ext4
  • /dev/sda2 - raw

raw partition write pointer position

root@elphel393:~# cat /mnt/sda1/camogm.disk    
Device          Start LBA       Current LBA     End LBA 
/dev/sda2       12500992        38196200        250068992

How much is written:

(Current - Start)*512/2^30 GB

scripts for downloading from internal SSD (via eSATA)

~$ ssh-copy-id root@192.168.0.39
~$ ssh-copy-id root@192.168.0.38
~$ python3 int_ssd_download.py -h
# Download 100GB from each
~$ python3 int_ssd_download.py -c root@192.168.0.39 -n 10 /path
~$ python3 int_ssd_download.py -c root@192.168.0.38 -n 10 /path

This script:

  • creates a UID (/path/UID) directory, where UID - ID of the SSD
  • switched the SSD to eSATA port

Note: Essentially the script does dd. If there is no eSATA cable it's possible to run dd over network. Something like:

ssh root@192.168.0.39 "dd if=/dev/sda2 bs=20M count=10 | gzip -1 -" | dd of=image.bin.gz

scripts for extraction

~$ cd /path/UID-of-192.168.0.39
~$ /path-to-script/split_mov_jp4.php 0
~$ cd /path/UID-of-192.168.0.38
~$ /path-to-script/split_mov_jp4.php 4