I want BI to send me a very short video via email when an alert is triggered. Currently I have BI configured to send me 7 seconds videos. This part is working, but the first 4-5 seconds are wasted because there is never any motion in them during this time. Why do the videos start several seconds before alert motion is detected? Can this be fixed so the videos start when the alert is triggered?
Videos via email start 4-5 seconds before motion is detected ...
- Thread starter ken1970
- Start date
looney2ns
IPCT Contributor
See Pre-trigger record time. If Fully INclude with alert is checked, un check it.
Otherwise, reduce the Pre-trigger time to your liking.
Otherwise, reduce the Pre-trigger time to your liking.
+1^^.
From BI's built-in "Help", under "Recording Options" => "Video Options":
From BI's built-in "Help", under "Recording Options" => "Video Options":
Video Options
The pre-trigger record time applies only to when triggered or when alerted recording. This isa useful feature for capturing the moments leading up to a trigger event. There are a coupleof considerations when using this however, depending on whether or not you are using“direct-to-disc” recording (discussed in the format and compression topic below). Without direct-to-disc, all pre-tigger frames will be encoded at once upon trigger—as this has the potential to require time and CPU resources, you should keep the pre-trigger time to a minimum, ideally just a few frames. If you are using direct-to-disc recording, this is not a concern, as the frames are pre-encoded—however you must be mindful that recording can only begin on a key frame and not any arbitrary time in the stream. Key frames are generally spaced at 1 second intervals, but you should take a look at the Cameras pages in Status to see what your camera is sending.
When an alert is replayed or exported, by default up-to 2 seconds of the pre-trigger record time is included as part of the playback. This allows you to see movement immediately leading up to the trigger while still recording the full pre-trigger time. If you’d prefer that alert playback begin earlier, at the beginning of the pre-trigger time, select the option to Fully include with alert.
In my old version of BI dated June 2020 (5.2.9.19) I do NOT have a setting called "Pre-trigger record time" as shown in the image above. Instead I have a "Pre-trigger video buffer" setting, and it does not come with the "Fully include with alert" checkbox option. Also my Video drop-down does not offer "Continuous + Triggered" so I use Continuous , and BI is set to use the camera's substream as my main stream so I can minimize the size of saved video files (is there a better way to deal with this?).
My BI "Pre-trigger video buffer" setting is checked with a 0.5 second value. When I UNcheck this setting the emailed videos still waste several seconds before motion begins. I am currently using BI with one (eventually five) Reolink RLC-410 5MP camera(s). Apparently these cameras do not allow me to set my own key frame interval ... or at least I have not found a key frame setting in the Reolink admin interface yet. And yes, I am using direct-to-disc, so apparently the following key frame info is important in this situation:
"If you are using direct-to-disc ... recording can only begin on a key frame and not any arbitrary time in the stream. Key frames are generally spaced at 1 second intervals, but you should take a look at the Cameras pages in Status to see what your camera is sending."
When I look at the Cameras page in Status, my FPS/key column shows values that are constantly changing. Here's one screenshot:
The FPS value actually ranges from 6.49-6.70 while the key value ranges from 0.20-0.30. I do not know how to interpret these values, but I will "guess" that when they are 6.59/0.20 (as in the screenshot above) it means that the key frame interval is 20% of the FPS value or 1.32 seconds. Is this correct? If not, can someone please tell me how to interpret these values so I can understand what key frame interval (in seconds) my camera is sending to BI?
Since I cannot set my own key frame interval in the camera itself, does this mean it's going to be impossible for me to get rid of most of the wasted time at the beginning of my emailed video files? Or is there a different way to approach this issue that I'm still not aware of ... aside from replacing my cameras or not recording direct-to-disc?
My BI "Pre-trigger video buffer" setting is checked with a 0.5 second value. When I UNcheck this setting the emailed videos still waste several seconds before motion begins. I am currently using BI with one (eventually five) Reolink RLC-410 5MP camera(s). Apparently these cameras do not allow me to set my own key frame interval ... or at least I have not found a key frame setting in the Reolink admin interface yet. And yes, I am using direct-to-disc, so apparently the following key frame info is important in this situation:
"If you are using direct-to-disc ... recording can only begin on a key frame and not any arbitrary time in the stream. Key frames are generally spaced at 1 second intervals, but you should take a look at the Cameras pages in Status to see what your camera is sending."
When I look at the Cameras page in Status, my FPS/key column shows values that are constantly changing. Here's one screenshot:
The FPS value actually ranges from 6.49-6.70 while the key value ranges from 0.20-0.30. I do not know how to interpret these values, but I will "guess" that when they are 6.59/0.20 (as in the screenshot above) it means that the key frame interval is 20% of the FPS value or 1.32 seconds. Is this correct? If not, can someone please tell me how to interpret these values so I can understand what key frame interval (in seconds) my camera is sending to BI?
Since I cannot set my own key frame interval in the camera itself, does this mean it's going to be impossible for me to get rid of most of the wasted time at the beginning of my emailed video files? Or is there a different way to approach this issue that I'm still not aware of ... aside from replacing my cameras or not recording direct-to-disc?
looney2ns
IPCT Contributor
fenderman
Staff member
- Mar 9, 2014
- 36,892
- 21,408
Other than the "videos via email" starting a few seconds earlier than desired, everything else seems to be working fine. When I view alerts directly in BI or via UI3 they always seem to start exactly when I would expect them to based on my settings. It is only the emailed videos that start sooner than expected. Then again, if I had known earlier what you guys just taught me, I would never have expected the emailed videos to exactly match my alert start times in the first place. So thank you all for helping me to better understand this situation!
I hope to switch to better cameras some day, upgrade BI to the latest version, and get a new computer to better handle the load. But for now I am resigned to use what I have. So the best solution I can think of right now is to have BI email me 10-second videos (instead of 5-seconds videos) and just live with the fact that the first few seconds of "no motion" on these videos will precede the activity that triggered the alerts.
I hope to switch to better cameras some day, upgrade BI to the latest version, and get a new computer to better handle the load. But for now I am resigned to use what I have. So the best solution I can think of right now is to have BI email me 10-second videos (instead of 5-seconds videos) and just live with the fact that the first few seconds of "no motion" on these videos will precede the activity that triggered the alerts.