PRIMER: What's needed to record a golf swing?

[FaultyClubs]

Every few months there's a new thread asking what hardware and software is available to record our golf swings. The usual suspects get discussed from cheap to expensive with no clear winners. It's a sad lot so I don't have any particular recommendations. BUT the subject does require specialized knowledge. It's the knowledge aspect I'll attempt to cover in this thread.

For me, a reasonable golf swing recording package should be able to do:

• "High speed" recording (ie more than 30 fps).
• Automatic capture
• At least two views possible, Down The Line and Face-On. But not necessarily at the same time.
• Immediate slow motion playback including frame by frame and smooth scrolling (ie jog shuttle).
• Ability to annotate basic lines, angles and maybe track paths (ie hands/club etc).

There is a lot more one could ask for but this list is a decent place to start.

The next several posts will cover the background knowledge needed to select such a system. They will also cover how to set up properly to record a golf swing. Finally I will recommend an el cheapo system to get you started.

[Ironstrokes]

Awesome write up here! Gonna start with the cheap ps3eye set up you mentioned after reading this and the other threads on automatic capture and play back. Cameras coming today and got the day off, so hopefully I get everything up and going by days end.

[Sascha1818]

would you mind posting a video of it ? and maybe how you set it up. Once my new room is complete i'm looking into doing the same

[inorkuo]

hey FaultyClubs, could you give me some pointers on how to set up tonedet? i've played around with it but i'm having trouble with the trigger thresholds, specifically the tone adjustment. what are your settings for golf ball strike detection? also is there a way for tonedet require a certain time to pass before triggering again?

[FaultyClubs]

hey FaultyClubs, could you give me some pointers on how to set up tonedet? i've played around with it but i'm having trouble with the trigger thresholds, specifically the tone adjustment. what are your settings for golf ball strike detection?

The key pieces to sort out are:

1. Make sure the sample rate is at least 2.5x whatever tone frequency you are trying to detect or it may not work. The default window length should be OK
2. Figure out the dominant/loudest frequency of your impact sound and set the tone frequency to that.
3. Make sure your soundcard settings drive the signal close to max without going over (ie clipping)

For item #2 you can guess at the dominant/loudest frequency values but could be there a long time. Best to actually measure it. There are probably spectrum analyzer type apps on a smartphone that will work but I've never looked. Find one with a peak hold capability.

NOTE: A while back I posted some pictures of my club/screen noise. You can look at that to get a clearer idea of what is happening. The link is: http://golfsimulatorforum.com/forum/...9174#post69174 and a few posts later. I use REW (and ARTA) on the PC to measure the noise since I'm familiar with those. It is a lot more complicated than you need though. Android spectrum analyzer apps should be fine.

I would guess it is probably simplest for most people to put the mic very near the club and trigger off the club sound. My iron's peak sound is in the 1-3kHz range and my driver is around 5.5kHz so I would pick a trigger tone in that range. Basically I'm looking for a frequency range that overlaps all my clubs and has the most impact energy. The default sampling rate would have to be raised given these frequencies.

NOTE: If triggering off club impact with a close microphone the Window Length could be shortened. One also has to make sure the soundcard isn't overloading.

Personally I don't like the mic where it can be stepped on so leave it on the shelf and trigger on the impact screen noise. My screen is the HQ hanging in front of heavy canvas so it has a low and loud THUMP. Screen noise from other setups could be significantly different. I doubt hitting into a net would work at all for example. That's why I'm saying putting the mic close to the club is probably the easiest although I haven't done it that way so you never know. .

The optimum threshold level setting depends on your mic/soundcard system and actual microphone location. For my setup with onboard sound and a separate microphone on my shelf, I set the Windows soundcard microhpone gain to 100%, turn off any boost and auto leveling and it works out to needing the -36dB threshold setting. On my laptop using the PS3eye built in microphones I use -24 dB threshold setting. A microphone a few inches from the club would need different settings.

I'm not sure my settings will help but FWIW, they are:

• Sample rate and Window length at their default settings (8000hz and 150ms)
• Tone Frequency set to 100 hz
• Detect level to -36 dB.
• Detection is on the leading edge (ie when the sound comes on).

Remember I'm triggering of the screen impact noise which is a loud THUMP in the 100-300 hz range in my setup. If yours is different then these values probably won't work.

I will say that if you are having problems with multiple triggering then it isn't right. It indicates you are triggering on a tone that has too little differentiation between background noise and impact noise. Probably because it is not actually set to the frequency of the impact noise loudest sound. But it may also be due to clipping in your microphone / soundcard setup.

A microphone near the club should be reliable because ToneDet (with default settings of 150ms window) looks for a very narrow frequency band.

If you still have trouble maybe describe your setup and we can go from there.

[FaultyClubs]

>> 3. Make sure your soundcard settings drive the signal close to max without going over (ie clipping)


A the risk of stating the obvious, also make sure ToneDet is actually using the correct microphone (ie the one you are intending to use).

[FaultyClubs]

hey FaultyClubs...also is there a way for tonedet require a certain time to pass before triggering again?

I don't know, don't think so.

Suggest making sure your script won't allow multiple instances. That way false triggers will be ignored. Something like the following at the start of your script:

-----------------------------------------------------------------------------------------------
#include <Misc.au3> ; For the Singleton function

;ignore multiple attempts to start script if already running
If _Singleton("mutex", 1) = 0 Then

;another script is running so exit
MsgBox($MB_OK, "Warning", "Script already running. Exiting.")
Exit

EndIf
------------------------------------------------------------------------------------------------

[inorkuo]

I will modify the script. Definitely a good idea as I locked up my computer when I set the thresholds in tonedet too low.

[Shardak]

Here is a sample of my new IDS 3140 camera. This is 1280x1024 @ 120fps, although youtube converts it down to 30fps it appears. My garage is lit by an overhead 60w light, and I have a small lamp shining on me. I will need to get some better lighting installed I have to turn gain and gamma all the way up, and that makes the image grainy. The focus is a bit off...need to adjust that a bit.

https://www.youtube.com/watch?v=5VHcWYjLGSM

It only does 60fps in Kinovea, with no options to modify its framerate, gain, shutter speed etc.

It works brilliantly in SwingCatalyst however.

I really like SwingCatalyst. Hate the price of it, but man its good. The camera is fully configurable with it, and the auto swing capture (triggered by mic) is great. I also like that it adds tempo info to each captured swing.

I may try and build an IDS interface to Kineovea. I am a .Net developer by day, and Kinovea is open source, written in .Net. The IDS software package that comes with the camera includes a .Net SDK that appears to be fairly easy to implement....I am going to spend some time on this over xmas break. If I cant get it working, I will probably pay for SwingCatalyst.

The Computar 4-8mm lens that I got for $40 is just OK. There is a fair amount of fish-eye distortion at the edges.

Here is a screenshot of Swing Catalyst:

[Shardak]

>>Why did you record at 1280x1024 @ 120fps?

I dont see any option in Swing Catalyst to change resolution, so it records at the default camera resolution. Also, until I get more lighting installed, even 120fps is too dark.


>>Does it work at the full frame rate of 224 fps?

No, it is limited to 170fps in Swing Catalyst. The reason for this is that SC only allows a max pixel clock of 288. The 224fps limit of the camera has only been enabled in the latest IDS software, which allows you to boost pixel clock to 320. This works fine in uEyeCockpit, but is not a setting that is enabled within Swing Catalyst.


>>How about the reduced resolution (ie 640x480) higher frame rate modes?

I dont see any way in Swing Catalyst to run at different resolutions.


>>No dropped frames?

Correct. Even at max 224fps mode, I see no dropped frames in uEyeCockpit. The same for 170fps mode in SwingCatalyst. I will be adding a 2nd camera and hope that my laptop can keep up with both.


>>Kinovea stuff

I am running 8.25, and it has strange behavior with the IDS camera. Sometimes the image is upside down during capture. So I dont think the DirectShow filter in Kineova works well with the latest IDS software. There may be a combination of Kinovea + IDS drivers that work better, but I have not experimented with it enough.

[pgapro0825]

Hi Shardak, I have been looking at Swing Catalyst and have a quick question. How far back is your camera positioned? I have limited space as most and likely running at the minimums for the recommended camera placement.

Thx

[Shardak]

pgapro0825:

My camera is 9 feet back from where I stand.

I would guess it would work fine with 7 feet of space. Closer than that and it might be too close.

[awisnia]

Great stuff - This one works really well and has the most important feature - automatic capture and replay in slow mo.

http://www.swingprofile.com/

[Shardak]

I have started work on adding IDS camera support to Kinovea. After some struggles getting the code to build, I have everything building correctly.

My only progress so far is to build the core interface to the app that will detect a plugged in IDS camera. Its working well. I can see my IDS camera listed in Kinovea, and can see the IDS API code is loading and exposing all the configuration options that the camera supports.

My plan will be:

1) Build core functionality: Capture snapshot, capture video (using camera default configuration).

2) Build basic camera configuration screen in Kinovea. This will allow user to configure: resolution, pixel clock, frame rate, shutter speed (exposure), gain, gamma.

3) Build a settings import that will take a full .ucp file exported from the IDS uEye Cockpit app, and use it to configure the camera. There are many dozens of options that you can configure in uEye Cockpit. Instead of trying to duplicate a UI for all those options in Kinovea, I will just load the config file that was exported from uEye Cockpit, and use it to configure the IDS API.

I have passed the first 2 hurdles...getting the Kinovea source code to build, and plugging in IDS API. Hopefully I can make this work.

[Wigalo]

Great thread guys. Video capture is my next sim room upgrade. Question...when I had the GSA sim, I used infra red lights for my h and v cams. Would IR lighting work with with the high speed cams so that I don't have to flood the room with incandescent light?

[aja]

Not sure about IR but incandescent is not your only other choice.

I have CFLs (compact fluorescent) and LED floodlights and neither affects my ProTee sensor which relies on the overhead Halogens.

[FaultyClubs]

Great question! I don't know anyone who has done it.

Most of these image sensors respond into 700nm range so if your lights are around there then it will probably work. Some sensors are better than others in the IR range so you'd want to verify with your chosen sensor. In general you'll give up a bit of sensitivity though. And a lot if your lights are into the 800nm range.

You'll also need a lens that responds to IR (typically lenses on these cameras are designed to block IR). And of course it won't be color, it will be a slightly weird looking monochromatic IR image.

You'd also want to make sure that much IR light in the room doesn't mess up the GC2.

Anyway given all those caveats it could work. Sounds like an interesting experiment!

[FaultyClubs]

Shardak reminded me of something i should have mentioned in the theoretical section. Once frame rates get over 50/60 fps then flickering from lighting starts to become an issue.

Solutions are use DC lighting, LEDs designed to be flicker free (film industry), high frequency electronic ballasts for cfl, flicker free hmi lights (again film industry). Also regular tungsten becomes flicker free once the power gets high enough so element doesn't cool down (500w to 5000w depending on your frame rate).

[Shardak]

I have made some progress getting IDS cameras integrated with Kinovea.

Here is my IDS 3140 running at 800x600 getting about 190 fps.

[Igor-247-golf]

IDS would be aweosme... I still have a lot of them left over but could never get them to work with Kinovea!

[Fhacker]

awisnia just downloaded swing profile on my iPad. Looks good I will try it tomorrow

[awisnia]

Fhacker I use it a few times a week. Have an ipad stand in my hitting bay. The auto replay feature is incredibly simple - you just hit, it beeps - and loop -replays your swing at 1/4, 1/2 or full speed until it senses the next hit. Saves them all, lets you annotate, compare with pros or yourself. Under-priced IMO. Also, I use it with one of my kids iPhone 5's with a cracked screen - right into hdmi converter into an old monitor.

[DWargo]

I'm looking for a little camera expertise and many of you have already been through this process. I am out of my element. I am setting up a swing replay system, likely with Swing Catalyst. I have ordered IDS 3140 color cameras and need to know what lenses to use for them. They are C-Mount but with my searches, I am a bit overwhelmed. My face on camera will be mounted on a wall a touch over 7' away and down the line camera is about 9.5'. Calculators indicate that I need slightly less than a 4mm lens on the FO view and slightly more than 4mm on the DTL view. The problem is I see a wide variety of lens types and cost and want to ensure I get the correct ones with good quality and minimal distortion. Shardak mentioned a cheap 4-8mm Computar option earlier but even with that search there are several types. Can you or someone else help with potential model numbers so I can narrow my search? Also, what are key criteria for "quality" for lenses that drive the variability in cost?

Thank you for any help that you can provide. This thread has been very helpful for me. Thanks guys!

[Baller]

I have a Tamron M12VM412 that seems to work fine for me. It's 4-12mm.

[Baller]

Shardak, I now have a 3140 and would love to know what your settings are and what lens you are using. Any tips would be appreciated including what lighting you added to get the best results between screen and video results. Thanks!

DWargo, what did you end up going with and how's it working out?

[FaultyClubs]

I've finally got around to trying the kayeton global shutter camera I've mentioned a few times elsewhere on the forum. Link here: https://www.amazon.com/gp/product/B0...6QRNEM25&psc=1

Forum experience has been the popular OV2710 ELP camera (640x480) reports 120 fps but actually only runs at 100 fps. This causes incorrect playback speed and jittery video due to internally dropping frames. Some have requested the manufacturer to modify the camera to run at 100 fps to solve these problems. This is a good solution if buying that camera. For people on a tight budget a 100fps version of the OV2710 ELP camera is a useful increment over the PSeye camera.

This Kayeton camera is another step up over the ubiquitous OV2710 ELP in that it has a GLOBAL shutter, improved resolution at 1280x720p, and runs at a true 120 fps. At $85 for the Kayeton versus $45 for the ELP I find the Kayeton well worth the price. Noticeably better quality image, brighter, a true 120 fps and of course the global shutter. It does have some downsides however in that the gain is fixed in manual mode so deliberately underexposing to reduce motion blur and compensating with increased gain does not work on this camera. In auto mode, it does seem to alter the gain as needed. Also I was unable to get enough light to freeze the club head with absolutely zero blur so the minimum shutter duration may be insufficient for zero blur. However this is somewhat moot in that the amount of light needed would be too much for indoors anyway (these small sensors need to be used outdoors if you want to freeze the club head). Another potential downside for some is the single video mode (1280x720p at 120fps) so if you need other resolutions this camera is not suitable. Overall the camera does exactly what it claims and does it well. It is UVC compliant so should work in all modern Windows software.

Kayeton made the Amazon link for me since I wanted the 2.1mm lens and they don't normally sell it with that lens (I have a range of other lenses plus a 2.8-12mm zoom lens). The 2.1mm lens is a high quality lens but does suffer from noticeable barrel distortion typical of these lenses. If you have the space get at least a 2.8mm lens or try the version with a 2.8-12mm zoom (I have what looks to be the same zoom on my ELP camera and find it to be very good quality).

EDIT: I should also mention Kayeton has a OV4689 based camera that squeaks out 330 fps at 640x360. It is a rolling shutter camera and is UVC compliant. I have little interest in this combination (small sensor, rolling shutter, low resolution) so haven't tried it but should work ok if you have enough light (not easy at 330 fps given such a small sensor). Make sure your software can handle the speed. Overall probably not the best option for most people although one could just use it at 120 fps and 1280x720p if they were happy with the rolling shutter. It would be useful to compare both cameras at 120 fps but someone else will have to do that given my lack of interest in this camera.

[FaultyClubs]

I don't know, sorry. Does the Trackman work with generic webcams? If so it should work being UVC compliant. It's a decent camera for the price if you can live with the limitations mentioned above.

I've asked if a version with manual control of the gain and an extra stop on the shutter speed would be possible.
They said they'd look into it but then went radio silent...we'll see how that goes.

[F.Trey]

AFAIK it does, but at times it seems finicky with some hardware for no apparent reason. Might not be TM related, more PC. For the price it looks like good value. What would you say is a step up from it? I liked the IDS 3240 apart from it being only 60fps but higher speed IDS global shutter cams seem to be expensive (got the 3240 second hand). I don't mind spending more for a noticeably better of more user friendly cam. I came across a IMX273 based cam for €200 without lens that looks promising for instance (http://www.daheng-imaging.com/en/pro...productid=3380).

[FaultyClubs]

I wouldn't say either camera is "better" than a 3240. If you liked the 3240 but want more fps then maybe a 3140. That's assuming the 3240 doesn't have a higher speed mode (most do). The smaller sensor cameras you mention will certainly be cheaper. And the driverless ones easier to use. But "better" really depends on your requirements. Suggest starting a new thread listing your requirements and see what people can suggest.