Rather new to Bluetooth Low-energy devices, and having recently purchased a bunch of trackers off Amazon, decided to write a little application to see what type of information I can get from these.
The trackers are from a Chinese company, and they don't have a ton of information around advertisement information, so I'm playing by best guess here.
What I've been able to achieve so far, through Flutter Reactive BLE, is to find the devices by their ID (filter out additional noise I don't care about) and pull information like RSSI, Name and ID from it.
Now I want to interpret the manufacturerData object, screenshot attached of just one of them, and can't seem to get anything concrete from it.
I half assumed that reactive_ble would've stripped the leading checks and only supplied the the necessary portions of the data object that's relevant to interpret, however, this does not seem to be the case.
My first feel was to just convert this UInt8List to String utf8.decode(device.manufacturerData), however, this returns either a 1x spaced string or nothing at all.
I've tried using ByteData with a start of 3 and end of 4, and that's not very helpful either.
Is there something I'm missing in it's interpretation? I've read the Bluetooth spec and as I don't come from a CompSci background, is rather foreign to me, so would appreciate a layman response.
The first 16 bits (little endian) in manufacturer data contain the manufacturer id (Bluetooth SIG's web site has a list). The layout of the rest of the bytes are totally up to the manufacturer. If you can't guess what they mean, you'll have to ask the manufacturer.
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I have been handed many GC Dev boards and SOMs at work but there seems to be no external way to tell them apart from looking at part/model numbers. My coworkers are disorganized and have mixed three different orders together and we cannot tell which is which anymore. I could turn them all on and look in the terminal but certainly there must be an easier way. I dont know why there is no label or discerning factor on the packages or SOM itself. The Datasheet says this only: These numbers don't correlate to any numbers on the actual SOM Board I have a model number that's the same for all of them, "AA1" but at the top is "09JF001TK" which contains the date it was manufactured but I cannot decipher what the other letters/numbers mean. I sent in a support request but have not heard back, hope you can help. Both QR codes don't seem to yield any results
We're looking to share AR experiences (ARWorldMap) over the web (not necessarily to devices nearby, I'm referring to data that can be stored to some server and then retrieved by another user).
Right now we're looking into ARWorldMap which is pretty awesome, but I think it only works on the same device AND with devices nearby. We want to be able to delete these constraints (and therefore save the experience over the web on some server) so that everyone else can automatically see 3D things with their devices (not necessarily at the same time) exactly where they were places.
Do you know if it's possible to send the archived data (ARWorldMap) to some server in some kind of format so that another user can later retrieve that data and load the AR experience on their device?
The ARWorldMap contains the feature points in the enviroment around the user. For example, the exact position and size of a table but including all the other points found by the camera. You can visualize those with the debugOptions.
It does not make sense to share those to a user that is not in the same room.
What you want to do is share the interactions between the users, eg when an object was placed or rotated.
This is something you would need to implement yourself anyway since ARWorldMap only contains anchors and features.
I can recommend Inside Swift Shot from last years WWDC as a starting point.
Yep technically it’s possible as according to docs here. You will have to use the nsssecure coding protocol, might have to extend if you aren’t using a swift backend though. It’s still possible as the arkit anchors are defined by a mix of point maps, rotational data , and image algos. Just implement portions of codable to JSON and voila it’s viable for most backends. Of course this is easier said then done.
I'm in charge of technology at my local camera club, a not-for-profit charity in Malvern UK. We have a database-centric competition management system which is home-brewed by me in Delphi 6 and now we wish to add a scoring system to it. This entails attaching 5 x cheap-and-standard USB numeric keypads to a PC (using a USB hub) and being able to programmatically read the keystrokes from each keyboard as they are entered by the 5 judges. Of course, they will hit their keys in a completely parallel and asynchronous way, so I need to identify which key has been struck by which judge, so as to assemble the scores (i.e. possible multiple keystrokes each) they have entered individually.
From what I can gather, Windows grabs the attention of keyboard devices and looks after the characer strings they produce, simply squirting the chars into the normal keyboard queue (and I have confirmed that by experiment!). This won't do for my needs, as I really must collect the 5 sets of (possibly multiple) key-presses and allocate the received characters as 5 separate variables for the scoring system to manipulate thereafter.
Can anyone (a) suggest a method for doing this in Delphi and (b) offer some guide to the code that might be needed? Whilst I am pretty Delphi-aware, I have no experience of accessing USB devices, or capturing their data.
Any help or guidance would be most gratefully received!
Windows provides a Raw Input API, which can be used for this purpose. In the reference at the link provided, one of the advantages is listed as:
An application can distinguish the source of the input even if it is
from the same type of device. For example, two mouse devices.
While this is more work than regular Windows input messages, it is a lot easier than writing USB device drivers.
One example of its use (while not written in Delphi) demonstrates what it can do, and provides some information on using it:
Using Raw Input from C# to handle multiple keyboards.
Local travel cards in Saint-Petersburg, Russia have got huge id numbers that aren't easy to read and type into a web page when topping up the card online. So I want to build a small app that would take a photo of a travel card and parse the number out.
The task is a bit easier than a free form recognition:
card is of the very well known size
id numbers are of known size, are located in the very well known location on a card and they are number only, no letters (okay, there are two variations I think and maybe they will add 1-2 more in the future)
even the font is known in advance
even the first several numbers are the same for most of the card (so far there are only two prefixes used)
How would you do it? Are there any libraries tuned not for the general OCR, but for a "hinted" OCR like I need?
Best regards,
Artem.
P.S.
Actually a free/cheap web service for this task would also be good enough
Yes Google has a library called Tesseract and there is an iOS SDK on Github you can import into your application. So you can use this SDK and it has some documentation that you can read that will explain how to set it up in your app. It has methods that will return you a string with the text of the card in the string. BUT it will be ALL of the text from the card. So best thing to do would be to:
1 "clip" the original image to extract a sub image that displays only the portion of the card you wish to get the numbers from.
2 Process this sub image through Tesseract to retrieve the string you are looking for.
3 Then parse through the string and pick out the data that you need.
But just be warned, it can be a bit quirky. This SDK tends to recognize words best from images that are scanned, not "taken a picture of". Because although it is an advance piece of technology, it isn't perfect. So to get it to work as perfectly as possible for you, try to get scanned copies of the originals.
Best of luck.
The ideal solution for you would have three components:
1) Detection of the card. This is useful because if you have the detection, then the end users have much easier time actually using the scanner, because they can place the phone above the card in an arbitrary direction
2) Accurate OCR component. Ideally, customizable for this exact font you have on the card, for the exact position on the card.
3) Parsing mechanism. This would enable you to obtain the exact string written on the card without writing huge amount of OCR parsing code.
BlinkID SDK has all this. It has a preset for detection cards in the ID-1 format. It has integrated OCR engine. And it provides RegexParser, where you can define the exact format of the text which you're trying to extract from the document.
BlinkID was initially built for scanning ID documents which have very similar properties as the problem you're trying to solve.
Note. I'm one of the developers working on BlinkID.
Is it possible to get location data out of Google Gears, Google Gelocation API or any other web location API (such as Fire Eagle) in such a format that it appears to other software as a GPS device?
It occured to me reading these answers to my question regarding WiFi location finding, on Super User, that if I could emulate a GPS unit, many of these web services could act as a 'poor-mans' GPS to otherwise less useful software that requires it.
Is GPSD an option?
Preferably OSX & Python, but I would be interested in any implementation.
There is a very similar thread on a Python mailinglist that mentions Windows virtual COM ports and discusses Unix's pseudo-tty capabilities. If the app(s) you want to use let you type in a specific tty device file, this may be the easiest route. (Short of asking the authors to provide a plugin API for what you're trying to do, or buying yourself a $20 bluetooth GPS mouse.)
Are you using OS X?
There is a project macosxvirtualserialport on Google code that provides a graphical wrapper around some of the features of a utility called socat. I'd recommend taking a look at socat if you see potential in the pseudo-tty route. I believe you could use socat to link a pipe from a Python program to a pseudo-tty.
Most native Mac apps will be querying IOServiceMatching for a device with kIOSerialBSDRS232Type, and I doubt that a pseudo-tty will show up as an IOKit service.
In this case, unless you can find a project that has already implemented such a thing, you will need to implement a driver as described in this How to create virtual COM port thread. If you're going to the trouble of create a device driver, you would want to base it on IOKit because of that likely IOServiceMatching query. You can find the Apple16X50Serial project mentioned in that post at the top of Apple's open source code list (go to the main page and pick an older OS release if you want to target something pre-10.6).
If your app is most useful with realtime data (e.g. the RouteBuddy app mentioned in the Python mailinglist thread can log current positions) then you will want to fetch updates from your web sources (hopefully they support long-polling) and convert them to basic NMEA RMC sentences. You do not want to do this from inside your driver code. Instead, divide your work up into kernel-land and user-land pieces that can communicate, and put as little of the code as possible into the kernel part.
If you want to let apps both read and write to these web services, your best bet would probably be to simulate a Garmin device. Garmin has more-or-less documented their protocol in the IntfSpec.pdf file included with their Device Interface SDK. Again, you'd want to split as much as you could into user-space code.
I was unable to find a project or utility that implements the kernel side of an IOKit-based virtual serial interface, but I'd be surprised if there wasn't one hiding somewhere out there. Unfortunately, most of the answers I found to that question were like this, with the developer being told to get busy writing a kext.
I'm not exactly sure how to accomplish what you're asking, but I may be able to lend some insight as to how you might begin to get it done. So here goes:
A GPS device shows up to most systems as nothing more than a serial device -- a.k.a. a COM port if you're dealing with Windows, /dev/ttySx if you're in *nix. By definition, a serial port's specific duty is to stream data across a bus, one block at a time. So, it would then follow logically that if you want to emulate the presence of a GPS device, you should gather the data you're consuming and put it into a stream that somehow acts like an active serial port.
There are, however, some complications you might want to consider:
Most GPS devices don't just send out location data; there's also information on satellite locations, fix quality, bearing, and so on. Then again, nobody's made any rules saying you have to make all that data available. There's probably more to this, but I'll admit that I need to do more research in this area myself.
I'm not sure how fast you can receive data when dealing with Google Latitude, etc., but any delays in receiving would definitely result in visible pauses in your "serial port"'s data stream. Again, this may not be as big a complication as it seems, because GPS devices are known to "burst" data across the bus anyway, but I'd definitely keep an eye on that. You want to make sure there's always a surplus of data coming across, not a shortage.
Along the way you'll also have to transform the coordinates you receive into valid GPS sentences, as well. You can find specifications for those, but I would definitely make friends with the NMEA standard -- even though it is a flawed standard, it's the one everyone seems to agree on anyway.
Hope this helped you, at least a little bit. Are there anymore details specific to your problem that you think could be useful in answering this question?
Take a look to Franson GPS Gate which allows you to connect to Google Earth among other things (like simulating GPS and so on). Is windows only though but I think you could get some useful ideas from it.
I haven't looked into it very much, but have you considered using Skyhook's SDK? It might provide you with some of what you are looking for. It's available for every major desktop and mobile OS.