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Machine Vision

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how to increase avi read rate

Hi, Im reading in an existing video file and then analysing each frame for when an led comes on. This will be done using histograms or intensity methods. The problem i have is that it does this in real time. As in when i run the program it will pull each frame and analyse at the frame rate of the video. Ideally I would like to do this as fast a possible instead of waiting the 10 or so seconds it takes for the LED to come on. 

 

In short I would like to know how to read the frames faster than the frame rate, and analyse these so that I can find the frame of interest?

 

Thanks for any suggestions. 

Labview 14.0, Labview 12.0
CLAD
Mechanical Engineering Student
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Message 1 of 13
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Remove the delay.. 🙂
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Message 2 of 13
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there is some method to increase it 
send your vi I could tell you witch one is better for you 

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Message 3 of 13
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Here is the VI. As far as I know i haven't done anything with a delay

Labview 14.0, Labview 12.0
CLAD
Mechanical Engineering Student
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Message 4 of 13
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I can see the delay of 25ms.. o.O
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Message 5 of 13
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I thought about that but it doesnt affect it. When i set the delay to 0 nothing changes. the producer loop is what I need to speed up. the images I believe are being sent out to the queue at the frame rate per second of the video

Labview 14.0, Labview 12.0
CLAD
Mechanical Engineering Student
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Message 6 of 13
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i use there method for incease speed 
1 cut ROI

2 use all CPU core 

3 reduce number of frame that you need

for example some times you just need half of frame or every there frame just one 

check witch is better for you 

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Message 7 of 13
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A trick I would consider is to do two iterations.  In the first iteration, look at every tenth or twentieth image, and check if the LED is on.  Once you find an image with the LED on, you have to go back and analyze the last ten or twenty images to see which one the LED turned on in.  This will be much faster than checking every single image.

 

Bruce

Bruce Ammons
Ammons Engineering
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hi im now going to use histograms but my problem is the same. I'm using a producer and consumer arctitecture. How would i be able to implement your suggestion of using two iterations?

 

Thanks

Labview 14.0, Labview 12.0
CLAD
Mechanical Engineering Student
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Message 9 of 13
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did you check last vi that i sent to you ?
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Message 10 of 13
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