Calculating your own bowling speed using video

[bajrang]

rather then counting pixel count frames. put two measured landmark and count how many frame did the ball took to cross them. u will only have to know at what FPS (frames per second) does your camera shoot. rest is simple math.

[jaypatel33]

rather then counting pixel count frames. put two measured landmark and count how many frame did the ball took to cross them. u will only have to know at what FPS (frames per second) does your camera shoot. rest is simple math.

That is a good idea, but I use windows media center to replay my video, which has a frame rate of 0.04sec. So it would only be very lucky for the ball to match the landmarks at that given timeframe.

[Crookbond]

If you have a Mac, Final Cut Pro is an industry standard http://www.apple.com/finalcutpro/

[Magneto]

That is a good idea' date=' but I use windows media center to replay my video, which has a frame rate of 0.04sec. So it would only be very lucky for the ball to match the landmarks at that given timeframe.[/quote'] WTF is a frame rate of 0.04 sec? Download a Premier Pro, and start editing properly.

[jaypatel33]

WTF is a frame rate of 0.04 sec? Download a Premier Pro, and start editing properly.

Thanks man, finally a relevant answer, cheers

[jaypatel33]

WTF is a frame rate of 0.04 sec? Download a Premier Pro, and start editing properly.

On second thought, if I was measuring it my way, using arm length to determine length per pixel, the frame rate is irrelevant right, just need to consecutive frames of a known time difference.

[Pioneer]

Seems accurate enough

[bajrang]

That is a good idea' date=' but I use windows media center to replay my video, which has a frame rate of 0.04sec. So it would only be very lucky for the ball to match the landmarks at that given timeframe.[/quote'] player has absolutely nothing to do with this. frame rate of the video would be in the media information option that is provided in almost every player. now if you say your frame rate is 0.04 sec then that obviously mean you have no clue of what you are doing. you just need to re-shoot your video. put two markers on the grounds. for example 10 meter apart. draw a line between then and set camera perpendicular to that line making sure that both of the marker are easily visible in the camera frame. assume one marker as bowling crease. now bowl and record. count how many frames did it took for a ball to reach from one marker to another (can be easily done with quick time player). lets say it took 30 frames. now if your camera shoots at 30 frames per second it means you bowled at 10 meter per second. convert it to miles per hour via Google. done. for example 90 miles an hour balll would cross 10 meter markers in 7.5 frames on 30 frames per second camera. but most of the home camera i have seen now shoot at 60 frames per second. it means 15 frames for 10 meter for a ball going 90 miles an hour.

[Asim]

Why to take so much tension, say you got precisely accurate result e.g. 44.83 or 45.19, then what?

[jaypatel33]

player has absolutely nothing to do with this. frame rate of the video would be in the media information option that is provided in almost every player. now if you say your frame rate is 0.04 sec then that obviously mean you have no clue of what you are doing. you just need to re-shoot your video. put two markers on the grounds. for example 10 meter apart. draw a line between then and set camera perpendicular to that line making sure that both of the marker are easily visible in the camera frame. assume one marker as bowling crease. now bowl and record. count how many frames did it took for a ball to reach from one marker to another (can be easily done with quick time player). lets say it took 30 frames. now if your camera shoots at 30 frames per second it means you bowled at 10 meter per second. convert it to miles per hour via Google. done. for example 90 miles an hour balll would cross 10 meter markers in 7.5 frames on 30 frames per second camera. but most of the home camera i have seen now shoot at 60 frames per second. it means 15 frames for 10 meter for a ball going 90 miles an hour.

OK, I don't really follow, so maybe I don't quite get it. How do I know the frame rate then? Also if you could explain why my current method is wrong. Thanks

[bajrang]

OK' date=' I don't really follow, so maybe I don't quite get it. How do I know the frame rate then? Also if you could explain why my current method is wrong. Thanks[/quote'] if you are using window 7 left click on video file in window explorer go to properteies and under detail you would have frame rate option. now with regarding to your pixel method if your hand is closer to camera it would take more pixel then when it is far away from the camera. any sort of angle with camera would also mean that pixels will not represent equal distance. so chances of having any constant and acurate reading are nill with your method.