Increased FPS 25 on Dahua SD59225U-HNI smoothed auto tracking????

CCTVCam

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In one way this wouldn't surprise me as with a higher frame rate there are more frames to sample the change of position from.

What does surprise me from all these cameras though is the fact that the cameras never seem to track continuously. As you say, there's always a jerkiness where the subject moves and the camera then moves to catch up, then the same again in a kind of cat and mouse action. I suspect it might be down to the type of motors used. I'm guessing because these cameras have to move quickly to acquire a new target, the motors are designed for high speed movement so the turret can spin around quickly, whereas the movement required to track an object such as a person requires a low speed continuous movement, the motor can't replicate. So it moves in small on / off jerks to achieve the small movement increments.

Nice find on the frame rate though.
 

J Sigmo

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That is a good find. And it shouldn't be surprising.

If the frame rate we set not only sets the rate at which frames are compressed and streamed, but also sets the rate at which frames are captured by the camera and thus available to the camera's "brain" for use in performing tracking, then it should be no surprise that a higher frame rate should allow the camera's tracking to work better and more smoothly.

For a PTZ camera with autotracking, it would be nice if the camera could operate at its fastest frame rate for the purposes of analyzing targets for the autotracking, BUT also allow the user to set a separate frame rate for the purposes of compressing and transmitting the video over the Ethernet connection. That frame rate would need to be an integral factor of the main frame rate, of course, but that would likely be just fine.

So, for example, the camera could sample at 60 frames per second, and use all of that information for autotracking. But then you could select, 5, 6, 10, 12, 15, etc. FPS to be compressed and sent out the ethernet connection.

Of course, one fly in the ointment for this would be that you would always have a maximum frame rate imposed by using long shutter speeds. You obviously can't shoot 60 FPS if you're using a shutter speed of, say, 1/30th of a second. So you'd have to (as usual) make some tradeoffs when selecting the "real" and "transmitted" frame rates.
 
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Wildcat_1

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I noticed the same thing when I used 60fps On my SD6xxx even to the point of capturing an individual through an open window in their moving car. Now as we all know, there are a lot of other factors to ‘trying’ to get continually great tracking WITH a great image to boot, luck being a huge player ;)

I will say that I was playing with a different PTZ the other night and was super impressed with its abilities to track even the eraser on the end of a pencil. Was tracking smooth, continuous and fast. Will hopefully be testing more on this cam in a real world, non pencil test ;) but like all of us here would love to have auto tracking perfected a little more. Even things like setting horizontal boundaries, manual calibration within a target zone etc would be nice.



Could be a fluke will test more in next few days but increasing fps to 25 seems to smoothed tracking

That is a good find. And it shouldn't be surprising.

If the frame rate we set not only sets the rate at which frames are compressed and streamed, but also sets the rate at which frames are captured by the camera and thus available to the camera's "brain" for use in performing tracking, then it should be no surprise that a higher frame rate should allow the camera's tracking to work better and more smoothly.

For a PTZ camera with autotracking, it would be nice if the camera could operate at its fastest frame rate for the purposes of analyzing targets for the autotracking, BUT also allow the user to set a separate frame rate for the purposes of compressing and transmitting the video over the Ethernet connection. That frame rate would need to be an integral factor of the main frame rate, of course, but that would likely be just fine.

So, for example, the camera could sample at 60 frames per second, and use all of that information for autotracking. But then you could select, 5, 6, 10, 12, 15, etc. FPS to be compressed and sent out the ethernet connection.

Of course, one fly in the ointment for this would be that you would always have a maximum frame rate imposed by using long shutter speeds. You obviously can't shoot 60 FPS if you're using a shutter speed of, say, 1/30th of a second. So you'd have to (as usual) make some tradeoffs when selecting the "real" and "transmitted" frame rates.
Could be a fluke will test more in next few days but increasing fps to 25 seems to smoothed tracking
 
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