can motion-detect trigger a still frame capture, as well as video?

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cam235

Pulling my weight
Oct 5, 2016
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I have a 4MP camera, Dahua IPC-HF5421E. It's working fine with motion-detect triggering video record to the internal SD card. I'm using the MSIE web interface because I haven't fully figured out the SmartPSS program http://dahuawiki.com/Template:SmartPSS (I can't find a shutter speed setting there, for example) and the Chrome plugin won't allow login- I type user 'admin' but each character gets erased as soon as I type it, then 'no user found'. But the IE plugin works for most things at least.

Does anyone know, is it possible for motion-detect to trigger both a still frame as well as video? What steps are necessary to enable still frame capture? I see the time of day/day of week record schedule tabs, there is a video tab and still frame tab and both of mine look identical (all enabled 24/7).

I played around a little with the HTTP API (*) and was able to read out EventHandler, which showed RecordEnable=true and SnapshotEnable=false but so far have been unable to get "SnapshotEnable=True".

On my Hikvision, it did not capture a still frame until I enabled FTP upload even though I was going only to internal SD and not using FTP in any way. Maybe there's a similar obscure setting here?

* https://www.ipcamtalk.com/showthrea...node-dahua-api?p=118455&viewfull=1#post118455
 
not to local SD storage I dont think..
 
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In general, since there might be differences between firmware versions:
1. Enable snapshot on the specified event (motion, for example)
2. Check snapshot destination to be SD Card.
3. Check snapshot settings to be set to trigger.
 
yeah but where in the UI does it allow you to view those snapshots?
 
it should, but does it? Its been a while and it was on my first Dahua but IIRC I could playback recordings through the WebUI easy enough; but there was no method for obtaining snapshots.. mebe if you removed the SD card and looked at the filesystem; but thats not practical for anything but emergency recovery.

snapshot function seems mostly intended for sending emails and ftping to remote servers.. if you have a recording there is little point for a snapshot also.
 
I am happy to report that it works. Stills had indeed been captured in addition to video, but I just didn't know how to find them. In the MSIE browser plugin, under "Playback" you can select File Type: jpg and Data Src: SD Card and then you can see the files. The "play" control under the image does a (slow) slideshow through them.

Dahua-still-playback.jpg

Saving stills via FTP works too, but it certainly generates a deep folder tree. I'm used to one folder per day, not one per minute!
 
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I think a virtual beer is required. :) Should I send you our address at EVOSEC? :)

cam235 said:
Saving stills via FTP works too, but it certainly generates a deep folder tree. I'm used to one folder per day, not one per minute!
Click to expand...
In automation solutions/situations this is [very] useful...

P.S. As I stated before, this might be a firmware-dependent function... And it might be [or not] implemented.
P.S2. We've used it as a backup for slow connections/high-latency ones. What's your need?
 
I'm just playing around right now but the plan is to capture still images for remote analysis on another (local) machine, without needing to do external motion detection on video (even though that's probably the easiest route, it needs bigger hardware). Looking now like I should use an external trigger source to get the still to trigger at the right time. For example at night, motion is triggered by a car's headlights long before the car itself is in view.

I've been testing a lidar (older version of https://www.sparkfun.com/products/14032 ) which generally works OK if you can manage a fixed target on the other side of the street as a backstop, so you can trigger on a signal dropout even if your target is too dark to pick up directly.
 
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You can either fine tune the Motion Detection (zones, sensitivity etc) or use an external input to the camera (via alarms) - you might need to use a small hardware to add a delay for this.
 
why dont you just pull a jpeg directly from the camera feed? thats how I email all my alerts out..
 
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Thanks; I don't even know what is possible yet with this camera. is this what you're talking about?
Code: 
4.1.3 GetSnapshot

URL Syntax:   http://<ip>/cgi-bin/snapshot.cgi? [channel=<channelNo>]
Response:    A picture encoded by jpg

If that returns a JPEG captured more-or-less immediately after the HTTP request, that should work well. I will try it.
I do notice that the live feed shown in the browser has a few seconds of lag behind real-time.
If there is a big lag between JPEG request and the actual capture, that would make it not so useful.
 
your always going to have a second or two of lag, thats never going away with IP..

I just tested it on mine, ran it at the top of the min (11:37:00) and I got an image just a second behind (11:36:59)
 
Cool, so the JPEG is extracted after some amount of encoder/buffer delay, so it effectively looks backward in time. That's good so long as the delay is stable, then I can just wait approx. one second before sending the request, and I will get the moment I want.

Previously I have been using a MJPEG preview from a different camera that was low resolution but with very little lag, maybe under 1/2 second.
 
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