Laser distance measuring is useful, especially in architecture and engineering.
Professional, high accuracy tools are expensive however, so, as an architectue student, im looking for a way to use the LG V30's Focus laser to pull distance measurements.
The first question that arises is what its range is. Theres no need for a measurement tool thats limited to 4 meters when I'm trying to measure a house.
The second question is how the data itself is aquired. Does it beam a laser point onto the surface and lets the camera focus until the point is sharp or does the laser itself measure the distance. It does have a receiver by the looks of it, which means there must be some sort of data thats being processed, which we should be able to pull out. Seeing how the focus is very accurate (at least within the range of the cameras effective focussing distance, after all it goes to infinity focus at a distance of around 5 meters)
Finally, does anyone know the frequency of the diodes? This might be the ultimate limiting factor, if it is UV (which I doubt), it won't get very far considering it is fairly weak.
PyxelDE said:
Laser distance measuring is useful, especially in architecture and engineering.
Professional, high accuracy tools are expensive however, so, as an architectue student, im looking for a way to use the LG V30's Focus laser to pull distance measurements.
The first question that arises is what its range is. Theres no need for a measurement tool thats limited to 4 meters when I'm trying to measure a house.
The second question is how the data itself is aquired. Does it beam a laser point onto the surface and lets the camera focus until the point is sharp or does the laser itself measure the distance. It does have a receiver by the looks of it, which means there must be some sort of data thats being processed, which we should be able to pull out. Seeing how the focus is very accurate (at least within the range of the cameras effective focussing distance, after all it goes to infinity focus at a distance of around 5 meters)
Finally, does anyone know the frequency of the diodes? This might be the ultimate limiting factor, if it is UV (which I doubt), it won't get very far considering it is fairly weak.
Click to expand...
Click to collapse
This is a great question! I was wondering as well if its IR. Maybe if it is, we could some how make it into an IR blaster. I recorded a short video showing the laser light. I believe this is what you are talking about PyxelDE right?
Related
Reading all the gps threads at the moment got me thinking. Is it possible to create a program that could access the camera and use the information to provide exposure information?
Maybe even using it to create a light meter type tool?
Not asking if any one wants to do this, just the possiblity? Although if anyone does feel like a challenge!
I think given the nature of the sensor, you'd probably just have to sample the video data from the camera and average into a light level - however, you'd either have to disable or account for the auto-exposure control in the camera driver.
At least using the camera is quite easy from Camera API though!
V
ok, that would be useful! Is it possible to access the exposure meter of the camera?
hey,
I am down for helping. I could defiantly use a light meter in my phone. and im sure other would use it as wel.
Yeah, as semi-pro photographer i never walk out the door without my Hermes and at least 1kg of camera gear, so gadgets like this are always handy.
had a look at the api stuff, it seems that although there are commands to do with setting exposure they only refer to center-weighted or average. Would appear that we'd have to delve deeper than the camera api to impliment something like this...
I searched for this very thing a few weeks ago. There are software programs that will calculate exposure based on ISO, time of day, etc using standard exposure tables but this isn't very useful really. To me, I don't see using the tytn as a general exposure meter being very useful either as it's more accurate to just use your D-SLR's exposure meter.
However.. what WOULD be useful is if I could turn the tytn into a flash meter. My D-SLR can't do that and a pro flash meter is very expensive.
Any comments?
For those that don't know the difference, a flash meter waits for you to fire a strobe then gives you the meter reading based on that flash whereas a regular meter gives you a reading based only on ambient light conditions.
Several things, firstly I think the first step would be to create a standard exposure meter and work from there to see if anything could be done with flash metering.
Also not all my cameras are DSLR's. I have a thing about old cameras that half the time don't have a light meter or it doesn't work.
And finally it would be very education to create a light meter program. If the necessary information could be gathered from the camera there would be no limit to the ways in which the information could be used to calculate exposure. Imagine being able to take an image then highlight a certain area with the stylus and either weight the exposure in favour of that area or choose a "zone" to expose it to.
Still enough dreaming, does any know if enough information can be gathered from the camera?
We would need; an exposure time and a sensitivity setting for the sensor. None of these appear to be controlled through the API.
James
Interesting stuff in cool camera...
Just been playing with coolcamera to see what can be done with a 3rd part camera app. Looks interesting, although there is no way to control the exposure directly, the exposure can be "locked" allowing you to recompose and keep the same exposure.
If a default exposure could be "locked" in then it would be possible to use the resulting image to calculate the exposure.
Ok,
so i had an idea and not being that technically minded i thought id post it as a question instead of a statement...
Why wouldn't we be able to use the 3D's dual cameras just like the Kinect uses its?
Perhaps we could port software from one to the other...
Maybe on a 3d Windows phone.. but who knows...
sent from anything but an iPhone
That's not how it works.
The cameras are used for the 3D depth, sure, but the Kinect also uses an IR sensor to shoot tiny dots of IR light, covering the room. Your movements to block this light are also recorded by the Kinect and used in translating your motion on screen.
I'm sure there will be some cool uses for a 3D camera--but it won't ever be as easy as "porting straight over" or anything like that.
vegaobscura said:
That's not how it works.
The cameras are used for the 3D depth, sure, but the Kinect also uses an IR sensor to shoot tiny dots of IR light, covering the room. Your movements to block this light are also recorded by the Kinect and used in translating your motion on screen.
I'm sure there will be some cool uses for a 3D camera--but it won't ever be as easy as "porting straight over" or anything like that.
Click to expand...
Click to collapse
He is right, the technology you are talking about just isn't fully inside the Evo 3D like it is in the Kinect sensor, although I do have a few ideas on what to do with the added 3D capabilities as a developer myself. Nice job, thinking outside the box OP.
I mean, a 2D camera can do depth and motion sensing if you calibrate it properly and SPECIFICALLY (with say, ONE object to focus on like a ball, Playstation Move I'm looking at you).
A 3D camera will offer you the depth, but calibration might offer you problems. Sure it can sense and translate depth, but I think the point of the IR in the Kinect is to take away most of the calibration and calculations necessary from there, as well as increase the accuracy of the translation.
Put another way:
If I move in front of my 2D camera, it sees me get larger and smaller--stuff like that.
If I move in front of a 3D camera, it sees me move on an axis, as it can sense what's also around me--a front and a back, as it were.
If I move in front of a Kinect, not only can it see what's in front and in back of me to sense the depth, but it also knows exactly how many IR lights it's shooting out across the room, the exact distance between each one--and which ones I am violating with my motions.
Surely it is easier to say, "He's blocking these lights, which means he's at point (x,y,z)," than it is to say, "If the table is 5 meters away and is 1.5 meters tall, but it looks like it is x meters tall from this distance, and the man here is approximately 2 meters tall, and he's shrinking and growing by this much--that means he's approximately this far from us and this far from the table...."
In pure logical terms, it seems like there would be a LOT of calculations need to be done if you were to want to use a 3D camera for the ENTIRE of the motion sensing--which would limit the amount of resources available to the rest of your program and...etc.
On a computer, this might not be a problem, given enough resources and given what you aim to achieve. On a console...I remember hearing that the Kinect did use the Xbox SPUs to run calculations and that that DID limit the overall system resources in some way. On a phone? I expect some problems.
Not only with how you might intend to use it, functionally (hold camera so other people could play games? Use it for AR purposes?), but with the resources available to do it with. These are all interesting ideas, but I'm not convinced that a phone is yet up to snuff to do such constant calculation and dynamic calibration on the fly.
But I've been known to be wrong.
...from time to time.
My thought was to eventually be able to run motion sensitive games directly form the Evo 3D in 3D. Put the phone in a central position above or below my tv, connect a compatible controller and play BAD ASS 3D games or semi cool 2D games.
... you know seeing my idea spelled out like this really shows me how farfetched it really is, oh well maybe in 5 years you never know.
The kinect also uses some proprietary technology that they own. Well they did once they bought the company who designed it.
i think this can be done and someone should try it
one_mic_only said:
i think this can be done and someone should try it
Click to expand...
Click to collapse
vegaobscura said:
That's not how it works.
The cameras are used for the 3D depth, sure, but the Kinect also uses an IR sensor to shoot tiny dots of IR light, covering the room.
Click to expand...
Click to collapse
ten chars!
Doesn't the kinect also have a infrared beam to tell depth.... I think we are missing that..
Hi,
I have an e-bike. Just to test the GPS accuracy of my new watch i used the "bike" sport program. The top speed of my bike is around 20-24 km/h. The GPS tracking went really well, I am impressed there. However I saw rather strange and high heart rate readings. It was 113 bpm in average and 146 bpm as highest. I actually do not have much physical activity using the e-bike in full assist mode. I really have to push hard myself to get my heart rate to about 150 pbm.
I did repeat the test and got the same result.
So I have to conclude that, the watch checks my speed and thinks I am pushing hard on a "real" bike. It does not take the actual sensor reading, but something "pre-programmed" = fake one.
ventura1977 said:
Hi,
I have an e-bike. Just to test the GPS accuracy of my new watch i used the "bike" sport program. The top speed of my bike is around 20-24 km/h. The GPS tracking went really well, I am impressed there. However I saw rather strange and high heart rate readings. It was 113 bpm in average and 146 bpm as highest. I actually do not have much physical activity using the e-bike in full assist mode. I really have to push hard myself to get my heart rate to about 150 pbm.
I did repeat the test and got the same result.
So I have to conclude that, the watch checks my speed and thinks I am pushing hard on a "real" bike. It does not take the actual sensor reading, but something "pre-programmed" = fake one.
Click to expand...
Click to collapse
Hmm, it's probably that. Although it gives me approx. the same readings on my regular bike, but I'm just a fat bastard.
If you have a chance to wear some other heart rate bracelet simultaneously, do that, and compare results.
Sent from my LG-D858HK using Tapatalk
Their faking algorithm is well known to be very advanced... it also takes temperature, atmospheric pressure, activity duration, your weight, height, and age into account. It also manages to pass comparative tests to other similar devices and external heart rate monitors, and detects when you give your watch to another person and measures his HR correctly. Ah, yes, and yesterday I saw some bright lights in the sky - be prepared, the aliens are coming.
trueruer said:
Their faking algorithm is well known to be very advanced... it also takes temperature, atmospheric pressure, activity duration, your weight, height, and age into account. It also manages to pass comparative tests to other similar devices and external heart rate monitors, and detects when you give your watch to another person and measures his HR correctly. Ah, yes, and yesterday I saw some bright lights in the sky - be prepared, the aliens are coming.
Click to expand...
Click to collapse
Hi,
Can't decide what you are saying... So you mean the measurements should be correct and I am "making up" the complaints on the bad readings? Or else?
ventura1977 said:
Hi,
and I am "making up" the complaints on the bad readings?
Click to expand...
Click to collapse
it's different to say that "i get bad readings" (or not very accurate) and different "i get fake readings"
btw gps has nothing to do with the hr measures (common sense , gps is only for outdoor activities)
ventura1977 said:
Hi,
Can't decide what you are saying... So you mean the measurements should be correct and I am "making up" the complaints on the bad readings? Or else?
Click to expand...
Click to collapse
I've just showed you what happens when way of thinking is flawed, based on what I see when using only my amazfit device and taking your hypothesis that there is a faking algorithm involved. Nothing more. I suggest you read this article: https://en.wikipedia.org/wiki/Scientific_method , then continue your investigation into why in your case the watch is showing faulty(if it is faulty) data and in what conditions. Otherwise your proposition about faking is no different than the one about an alien invasion coming every time there is a bright light in the sky.
I kinda ran into a similar issue. I was wearing the Pace past the wristbone and had my Schosche Rythmm+ on the forearm connected to my Under Amour App on my smartphone and went for a walk/Run - the heartrate readings and caloric burn were way off. The highest my Pace Watch would show is about 110 or 120, but i was running 400M intevals with 2:30 minutes of rest in between. My Rythm was showing 140-160 on the sprints. Which is about accurate.
So I am question the ability and accuracy of the device. If we could connect to an external HRM via Bluetooth this watch would be killa!
I really like the watch and not trying to make up stories guys. It was a simple observation about an odd behaviour.
Somewhere I have saw posted that single measurements seems to be accurate, but if you ran a sport program it is way off.
I suppose the easiest way is to verify this is to run a program while sitting in the car or bus with gps good signal.
Is there a possibility that while on your bike felt adrenaline when you were going fast causing your heart rate to go up?
Honestly, if you want accurate heart rates get an Amazfit Health Band w/it's ECG sensor. http://amazfitcentral.com/amazfit-health-band-specifications/
I use mine for jogging. The first firmware was very accurate but after the OTA update it always said that heart rate too high, over 170. Then I have to keep the strap pretty tight to get better reading.
Then I changed the firmware to PACIfied version. Reading was good again & without too much tightening of strap.
I think the watch fakes it too.
I think it fakes it too.
Did some tests. Ran an intervall where it got all the way up to 195. Which was 10 beats off what the treadmill shows. Which is fine, not expecting it to be that accurate so high.
Then I walked flat for 6kmh and it detected 110 which is also OK. Then I walked 6kmh with 10 degree uphill.
Now watch still show 110, mill showing 150.
It doesn't detect the uphill.
I'm so extremely disappointed in this thing. Wasted 110$
jhenrikb said:
I think it fakes it too.
Did some tests. Ran an intervall where it got all the way up to 195. Which was 10 beats off what the treadmill shows. Which is fine, not expecting it to be that accurate so high.
Then I walked flat for 6kmh and it detected 110 which is also OK. Then I walked 6kmh with 10 degree uphill.
Now watch still show 110, mill showing 150.
It doesn't detect the uphill.
I'm so extremely disappointed in this thing. Wasted 110$
Click to expand...
Click to collapse
I'm going to run on the treadmill for thirty minutes, then put the watch on as soon as i stop the machine and see what the heart rate is.
FYI, had a Cambridge University educated doctor take my pulse and he said it was a lot less than what the amazefit watch was saying.
[Amazfit][Bip] heart rate sensor is a joke (firmware 0.9.40)
Hi, I have purchased the Amazfit Bip recently, it was cheap.
Several threads on the heart rate sensor of the Pace have try to warn against a possible fake feature.
I would like to extend this notice on the Bip after few tests.
I have posted a video on youtube to illustrate. unfortunately I am not able to post the link, here the title :
"Amazfit Bip heart rate sensors test."
Hope this helps.
here the description of the video :
A video of a heart rate test of the Huami Amazfit Bip watch. It can be seen that the watch does not offer a measurement but an estimate of the heart rate. This estimation rely on the time elapsed in the activity as seen in the first part of the video; but also on the information that can give the optical sensor, in the second part of the video. After turning off the camera, I started to move and put away my stuff and thus stress the accelerometer: the estimate of the heart rate has recovered.
The problem is that my heart rate could not exceed 60 bpm during the whole test (nothing doing it is around 54).
After several tests, this estimate seems made from several parameters:
- time: over time the heart rate increases in the effort
- what the optical sensor gives.
- the accelerometer : to detect an activity. (although in the first part of the video the watch does not move)
- parameters on age, weight, height, reported in mi fit, to establish a range of variation in the estimation of the heart rate.
Why that ? Maybe the sensor is unable to provide a measurement: the flash intensity is very low on this watch, the sensor covers a very small area.
What I expected: a measure like my polar f6
(without signal nothing is displayed: "--")
With a phone that has GPS and pedometer, it would have been better to invest in a Bluetooth module with electrodes.
Toni Maltes said:
Hi, I have purchased the Amazfit Bip recently, it was cheap.
Several threads on the heart rate sensor of the Pace have try to warn against a possible fake feature.
I would like to extend this notice on the Bip after few tests.
I have posted a video on youtube to illustrate. unfortunately I am not able to post the link, here the title :
"Amazfit Bip heart rate sensors test."
Hope this helps.
Click to expand...
Click to collapse
You're right, when missing data, the BIPseems to interpole the resullts with the data available.
If you put the BIP on your wrist during that time, it sloooooowwly go down to the HR. It's still rely to the old incomplete data that globally at this moment gives a false result.
That could be improved by software I hope.
EMPTY
RisenVe said:
Same here,
shaved my hairy arm at the bip position. Measured while riding my bike. Drived with 23km/h over all time and some sprinting intervalls to vo2/max. The Bip says at normal riding 110bpm +/-5 beats. But then, holy moly, at sprinting.... 130bpm +/-5 beats. On right arm i have used my mi band 2, on same height compared to bip. It says heart rate is between 80bpm at start up to 180bpm in sprint intervalls.
Click to expand...
Click to collapse
Are you sure it's tighten well ?
The sensor, is fully on your skin and doesn't move while riding?
Toni Maltes said:
Hi, I have purchased the Amazfit Bip recently, it was cheap.
Several threads on the heart rate sensor of the Pace have try to warn against a possible fake feature.
I would like to extend this notice on the Bip after few tests.
I have posted a video on youtube to illustrate. unfortunately I am not able to post the link, here the title :
"Amazfit Bip heart rate sensors test."
Hope this helps.
here the description of the video :
A video of a heart rate test of the Huami Amazfit Bip watch. It can be seen that the watch does not offer a measurement but an estimate of the heart rate. This estimation rely on the time elapsed in the activity as seen in the first part of the video; but also on the information that can give the optical sensor, in the second part of the video. After turning off the camera, I started to move and put away my stuff and thus stress the accelerometer: the estimate of the heart rate has recovered.
The problem is that my heart rate could not exceed 60 bpm during the whole test (nothing doing it is around 54).
After several tests, this estimate seems made from several parameters:
- time: over time the heart rate increases in the effort
- what the optical sensor gives.
- the accelerometer : to detect an activity. (although in the first part of the video the watch does not move)
- parameters on age, weight, height, reported in mi fit, to establish a range of variation in the estimation of the heart rate.
Why that ? Maybe the sensor is unable to provide a measurement: the flash intensity is very low on this watch, the sensor covers a very small area.
What I expected: a measure like my polar f6
(without signal nothing is displayed: "--")
With a phone that has GPS and pedometer, it would have been better to invest in a Bluetooth module with electrodes.
Click to expand...
Click to collapse
very interesting test, I already realized that the cardiac sensor of this watch gives me strange results sometimes.
I have no idea if it's the right forum, but this is a subject impossible to find answers for.
I had an idea for app development which requires acquiring information using the phone's camera. Smartphone cameras use CMOS sensors, which (usually) work with an electronic rolling shutter, that is, the pixels are exposed to light and then read and reset line-by-line, going from one end of the sensor to the other.
This leads to a delay in moment of light capture between the first line of pixels and the last. I wanted to make use of that effect by recording several points of time in one picture across several tenths of a second. The issue is that the "shutter travel" happens very quickly, too quickly for what I need; I don't know the exact number, but it's at least as quick as 1/90,000 of a second on my Mi 6 as I can get an image exposed for this little. My question is whether anyone familiar with development of camera-using applications knows if you can control the speed of that operation. It's not like performing something more slowly should be an issue in-and-of-itself, but someone elsewhere claimed it might be hard-coded by the camera manufacturer (Sony for example) to perform as quickly as determined possible. I need the electronic shutter to be slow moving and one pixel-line wide (which basically involves setting the exposure time to the shutter travel time divided by the number of scanned lines of pixels).
Now, if that's impossible to encode, my other idea is to record very high FPS (several thousands a second) at very low resolution, perhaps by reading only the middle portion of the sensor. Even 10x10 pixels might be enough. The question is also whether that is possible? A simple observance of the fact 2MP can be recorded today by most smartphones at (at least) 30fps shows that the bandwidth at least is well within the limit with 100pixels at 10,000fps. Also the shutter of course scans the pixels much more quickly if it can open about 3,000 lines of pixels in >1/90,000 of a second, but I don't know whether the process of saving a pixel takes a determined minimal amount of time regardless of how many pixels are handled in parallel.
Sorry for the long-winded questions. Thanks in advance.
Up.
Having liked the BIP so much it was soon joined by a Stratos and, most recently, by a 47mm Amazfit GTR. Reading the forum, of which I am a very new member, I saw that the GTR has been criticised for the performance of its GPS, something which is important to me.
The first thing I did was to check the 'static' accuracy of the GTR against a known standard. The readout from the GTR is only available to the nearest second of arc and when compared with a device with a known accuracy of 1/10th second of arc, it was accurate to the nearest second of arc. Here in the tropics a second of arc is pretty close to 30m in any direction. In short, the GPS is certainly accurate to that extent, but whether it has greater accuracy is a question I cannot answer.
Stationary, with my arm held out in front of me, time to fix is between 12 and 17 seconds in a less than perfect location. Time to fix with my arm held out in front of me while walking is longer. Time to fix with my arm swinging (ex-military) is a good deal longer. I use the walking exercise exclusively (at my age that's about the limit) so, having got a gps fix, my arm is swinging all the time and the resulting track is rather like that of a drunken man. As an experiment, while walking along the edge of a straight main highway, I held my arm out in front of me for a period of time and when later I looked at the track it was very accurate indeed, showing me exactly on the edge of the highway. An excellent result. This was repeated later during the walk, in a location that was less than ideal, with similar results.
As someone who has been involved in the reception of weak radio signals for almost 60 years, I am well aware of the extraordinary demands made on a tiny device but other, rather more expensive, watches seem to do better by all accounts. The inference that I draw from all of this is that the device has adequate accuracy but needs some tweaking to handle irregular motion of the watch on the wrist.... if that is possible.
In respect of the HR monitor, I see a considerable improvement over the Stratos and, over the normal range for resting heart rates 60-100 bpm, I have found it to be very accurate. This all assumes that it is worn correctly. To check its accuracy I simply performed simultaneous ECGs.
Sai Lang Kham
sailangkham said:
Having liked the BIP so much it was soon joined by a Stratos and, most recently, by a 47mm Amazfit GTR. Reading the forum, of which I am a very new member, I saw that the GTR has been criticised for the performance of its GPS, something which is important to me.
The first thing I did was to check the 'static' accuracy of the GTR against a known standard. The readout from the GTR is only available to the nearest second of arc and when compared with a device with a known accuracy of 1/10th second of arc, it was accurate to the nearest second of arc. Here in the tropics a second of arc is pretty close to 30m in any direction. In short, the GPS is certainly accurate to that extent, but whether it has greater accuracy is a question I cannot answer.
Stationary, with my arm held out in front of me, time to fix is between 12 and 17 seconds in a less than perfect location. Time to fix with my arm held out in front of me while walking is longer. Time to fix with my arm swinging (ex-military) is a good deal longer. I use the walking exercise exclusively (at my age that's about the limit) so, having got a gps fix, my arm is swinging all the time and the resulting track is rather like that of a drunken man. As an experiment, while walking along the edge of a straight main highway, I held my arm out in front of me for a period of time and when later I looked at the track it was very accurate indeed, showing me exactly on the edge of the highway. An excellent result. This was repeated later during the walk, in a location that was less than ideal, with similar results.
As someone who has been involved in the reception of weak radio signals for almost 60 years, I am well aware of the extraordinary demands made on a tiny device but other, rather more expensive, watches seem to do better by all accounts. The inference that I draw from all of this is that the device has adequate accuracy but needs some tweaking to handle irregular motion of the watch on the wrist.... if that is possible.
In respect of the HR monitor, I see a considerable improvement over the Stratos and, over the normal range for resting heart rates 60-100 bpm, I have found it to be very accurate. This all assumes that it is worn correctly. To check its accuracy I simply performed simultaneous ECGs.
Sai Lang Kham
Click to expand...
Click to collapse
Got me thinking. If there was a way to disable the motion step monitor, would it stop interfiering?