I am trying to create a low latency method to use an android device as a secondary display for a PC. So far all I have found has been either wireless streaming, or a slow usb connection (i.e. using iDisplay).
However, I found a DSLR camera contoller app (https://play.google.com/store/apps/details?id=com.dslr.dashboard/) that is able to stream a live feed of the camera to an android display via USB. Would it be possible to edit the source code of this application so it can read the video output of PC via USB? If so, how would you go about this? Do you think that this would be a low latency alternative?
Thank you!
Lots of fantasy in your question. Have you ever seen a PC outputting data from one of its USB ports to another device? How are you supposed to do that? With a plain male-to-male USB cable, in case you find one? Sorry but things don't go that way. To transfer data (files, or a network) via USB between two computers you'd need some propietary/specific software. Of course, once you have acomplished that is technically possible to transfer files with the screen content. Buy you'd need to develop a software that would capture the computer screen, compress it in real time, and send it through USB with enough low latency to be usable. That's going to be resource intensive.
A better, easier approach would be, maybe, using some sort of remote desktop or VNC on the Android machine, with the computer acting as a server. At least far more feasible than trying to implement a similar protocol by yourself.
Sorry but what you are trying to achieve is flawed from the beginning.
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First of all, I am extremely new to coding and I just learned the basics of java. I want to do an android app as my first project. The idea of the app would be to have buttons on your phone which would work as keyboard macros. I was wondering if I also needed to create specific windows drivers for it or if I could just make it run on the default windows keyboard drivers? As I said I am super new to all of this (about 10hrs of programming experience), so feel free to correct me and educate me as much as you want! I won't take it personally, I'm looking to learn :)
You would need to set up some sort of communication between the app and your PC. You wouldn't need to do anything with the keyboard drivers. Java has something called the "Robot class" which allows you to simulate a keypress.
Here is the documentation on the robot class: https://docs.oracle.com/javase/7/docs/api/java/awt/Robot.html
As for the communications, you will need to create a server/client connection. One of your devices will act as the client (probably your phone) and one will act as the server (probably your PC).
This is just a rough idea of how it would work but:
When you tap the button on your phone, it would send some specified data to your server that is running on your PC. You should set the data that gets sent from the client to the server as the key(s) keycode that you would like it to simulate so it will be easier to implement. When the server gets data from the client, it should send that data to the robot.keypress(data) function.
This honestly sounds like it will be a big project for your skill level but I wish you the best of luck on this. This will probably be a frustrating experience but don't let it get the better of you.
I am a web programmer and I am just wondering how software and hardware can communicate. I have basic knowledge in Java but I am not an expert.
Let's make it simple. I have a device which is just a simple lamp that can get switched on and off and it is connected via USB. My software has only one function - pressing enter.
By pressing enter I want the software to communicate with the USB port and tell it to activate the device. How would that be possible? Where do I have to start and what do I need to learn?
I understand that my question and my example sound silly but I am just trying to understand how it works.
I appreciate any help!
I think that if you using arduino or other prototyping board you might use rxtx serial library.
If I answer simply, then I should tell, you need to have microcontroller to do this by your own.
A microcontroller is a small computer on a single integrated circuit. A microcontroller contains one or more CPUs (processor cores) along with memory and programmable input/output peripherals. So, there are input, output pins for different operations you want to do with your physical hardware and also a memory to store the commands or program. That means a microcontroller is a third party which keeps communication active between the hardware and software in this case.
In the market, you can find many microcontroller integrated boards for building digital devices and interactive objects that can sense and control objects in the physical world.
To make your work easy as a beginner, I suggest you to buy an arduino board from the market. If you google it and search for arduino tutorials in youtube, you will find how they work. Hope these help you.
i'm doin my project in 8th sem telecomm engineering, and i'm plannin to create a DUPLEX(not confident whether it'd be full or half) communication app using bluetooth and wifi as channels,something more advanced than a simple walkie talkie, and i was wondering if this is possible for a one man army??? also i was wondering if it is possible to do so with android versions 2.2 and above... can i just program the bluetooth settings in app in such a way, that, it doesn't pop up for user permission to accept a voice message from the calling party??
and is there a possibility for creating multiple channels(one for Forward Voice Channel and one for Reverse Voice Channel) using bluetooth or wifi?? here's a list of few knowledge i possess:
JAVA: basics, done some gui in desktops, know some imp classes,only SE6...
WIRELESS COMMUNICATION: learning it this semester, stuff like how base station accepts incoming mobile station request and redirects it to dest, mostly 1g in our portions...
OPERATING SYSTEMS: general, looking forward to learning android and linux os...
C,C++,DSP,and SOME ELECTRONICS...
oh, and iwoul like to implement these well within 7 months duration...
people please ENLIGTHEN me with your wisdom and references to useful websites ASAP...
my THANKS AND WISHES to thee...:)
The first big problem i see is that on using wifi for this, and as i understood it is some sort of (advanced) walkie-talkie app with no rooter inbetween the communicating phones, you have to implement adhoc-wlan on your android device, which is not supported by android, so you will need a rooted device for that, and the implementation of adhoc-wlan on android is definitve possible (have a look at this code: http://code.google.com/p/android-wifi-tether/) but nothing easy (i have done it myself for an university project).
And you asked if you can avoid the permission pop-up for an incoming message, but on an android phone activating your bluetooth or pairing it with an other device will always ask for permission from the user.
I cant help about the multiple channels you were asking for.
As Answer to your big Question: "is it possible for a one man army?" i would say generelly yes, but it depends on how much other stuff you have to do. Since you were writing this is an project for university, i dont know if this is your only project and you can invest a lot of time in it. If so i guess it is possible, but it will be an quite big project and you should be willing to work yourself relativly deep into networking stuff.
On google.Code you can find some projects similar (at least the wifi part) to what you think about to do, take a look at them...
Idea: create a remote control for your android phone.
Why: I like listening music on my phone in a dock station with speakers connected. Now sometimes I want to turn the volume up/down, change the song, etc. So I need to unlock the phone, locate app that is playing music (Music player, internet radio app, etc.). Sometimes I manage to undock the phone or just mess something up and generally this s*cks.
So I would like to control my phone (on a data connection, not wifi) from the laptop (on wifi).
I had investigated couple of approaches and would like to get some recommendations on them:
Use XMPP. This is nice as there a lots of free XMPP services I can use. Two libraries (both based on smack) that I tried work just fine (Flow aSmack port and Beem smack port). I could automatically create new user on device and present some id/password combination that I (user) would enter on a desktop side to link both devices.
Use JXTA. Should be the next real deal but could be an overkill. I would imagine running a rendezvous&relay server somewhere (need to get hosting to work around firewall/NAT) and creating a peer group protected with password. Use device unique id and password (withing group) to link to the desktop application. (A great eBook explaining p2p and JXTA can be downloaded from here).
Use C2DM. Could be the answer, but notification delivery sometimes can take more then couple of seconds to deliver and there would be no feedback mechanism.
So far first solutions looks like a lot easier choice. Create custom extension or just create chat between both endpoints and use that for relaying commands/messages. But I wonder if I would be abusing XMPP system?
JXTA sounds great, but from all the reading I done it is apparent that it is designed for group communication and service sharing and not a solution for connecting two endpoints.
What do you guys think? I welcome all suggestions too.
UPDATE I do not want to remote to a phone and interactively control it. I want to establish a connection (socket connection) between laptop and phone even if both of them are on different networks secured behind firewalls, routers. With this I could define a protocol to issue commands to the phone (lower volume, mute, start app, etc.).
UPDATE 2 I'm giving JXTA a shot. It is a nice solution but lack of documentation is a bit of a downer. Got VPS FreeBSD server to test RDV/relay side of things. I keep updating this question further as it may be helpful for others.
UPDATE 3 Some more reading:
How to make two android devices to communicate through TCP
Connection between two computers without opening ports using a third computer
UPDATE 4
So far I did not have enough time to further continue my project. I did find an interesting project. At the moment project owners are re-writing their library, you can track their progress here.
why do not you try installing VNC server on machine and then use VNC client on laptop to access mobile
Mobile Shell (Mosh) maybe just the tool you are looking for. I have been looking for a good project to use Mosh, your idea seems pretty interesting :)
I want to make an app where it allows the user to give remote access to viewing their phone (first-person view of user using the phone). Kind of like how tech support can sometimes see what you're doing on your computer to help you with problems. Think "remote desktop for phone" is what I'd like to do.
Does anyone know if this would be possible?
My current idea to do this is screen scraping - somehow take a screenshot of the user's phone (like how DDMS does) every millisecond or something. This seems terribly inefficient though, and again I don't know if it's possible.
Note - the "receiver" of this first-person phone view can be a computer or website or whatever, along as they connect remotely.
It would be possible: extremely difficult, but possible, to implement an Android activity that uses a FrameLayout and hosts another Activity. You could then fetch the image buffer of the FrameLayout as shown here and you'd then have to feed that into a video encoder and stream the output of the encoder to a remote server, but that might work.
I actually wanted to create something like that as well...
First of all, it will only work on rooted devices, since access to the "screenshot" (framebuffer) is allowed only to rooted devices.
Now as to reading events from the controlling device - that's easy... The hard part would be to generate these events on the controlled device. But I'm absolutely sure it's possible for rooted devices, as I saw some similar program for Windows which controls the connected device (can't remember its name).
Anyway, the reason I stopped thinking about this app is its complexity and the fact only Rooted devices could be controlled.
Hope this helps