TLDR: I want some way to read HDMI data directly in code, rather than output it to a monitor. Doesn't really matter what language.
Background:
A friend of mine was curious about trying to write an AI for a video game we play, so we were discussing how to do it. At first he suggested to use a camera to read it and then feed that to the AI, but I was thinking there'd be less latency if you could just pull the visual data directly from the hdmi cable to use instead of adding another camera to the mix.
There seem to be some similar questions here, but all the one's I've found were unanswered.
After much google, I'm left with an unclear idea if it's even possible. There are some usb data analyzers, so if you could convert HDMI to USB, that's a possiblity. I'm just trying to figure out if
A) What I'm trying to do is possible.
B) What the best way to do it is.
Related
I am going to read the PC's music output and getting basic information (beat/tone/..) of the song played (then flash the lights accordingly etc). Can NAudio be used for the purpose and any samples? Sorry for this too general question at the moment.
TIA
-d
You can access your PC's output using WasapiLoopbackCapture. However, NAudio does not include a beat detection algorithm, so you'd need to find one yourself. There is a FFT class though which could be used to determine frequencies present.
I want to embed a video stream into my web page, which is part of our own cloud based software. The video should be low-latency (like video conferencing), and it would be preferable, but not required, for it to include audio. I am comfortable serving streaming binary data from the server-side, and embedding it into the page using HTML5 video.
What I am not comfortable with is the ability to capture the video data to begin with. The client does not already have a solution in place, and is looking to us for assistance. The video would be routed through our server equipment, and not be an embedded peice that connects directly to the video source.
It is a known quantity for us to use a USB or built-in camera from the computer. What I would like more information is about stand-alone cameras.
Some models of cameras have their own API documentation (example). It would seem from what I am reading that a manufacturer would typically have their own API which they repeat on many or all of their models, and that each manufacturer would be different in their API. However, I have only done surface reading and hope to gain more knowledge from someone who has already researched this, or perhaps even had first hand experience.
Do stand-alone cameras generally include an API? (Wouldn't this is a common requirement, so that security software can use multiple lines of cameras?) Or if not an API, how is the data retrieved from the on-board webserver? Is it usually flash based? Perhaps there is a re-useable video stream I could capture from there? Or is the stream formatting usually diverse?
What would I run into when trying to get the server-side to capture that data?
How does latency on a stand-alone device compare with a USB camera solution?
Do you have tips on picking out a stand-alone camera that would be a good fit for streaming through a server?
I am experienced at using JavaScript (both HTML5 and Node.JS), Perl and Java.
Each camera manufacturer has their own take on this from the point of access points; generally you should be able to ask for a snapshot or a MJPEG stream, but it can vary. Take a look at this entry on CodeProject; it tackles two common methodologies. Here's another one targeted at Foscam specifically.
Get a good NAS, I suggest Synology, check out their long list of supported IP Web Cams. You can connect them with a hub or with a router or whatever you wish. It's not a "computer" as-in "tower", but it does many computer jobs, and it can stay on while your computer is off or away, and do thing like like video feeds, torrents, backups, etc.
I'm not an expert on all the features, so I don't know how to get it to broadcast without recording, but even if it does then at least it's separate. Synology is a popular brand and there are lot of authorized and un-authorized plugins for it. Check them out and see if one suits you.
Let's imagine that we have any of popular photocameras (like Canon or whatever) installed on a mechanical platform. This platform allows us to accurately adjust camera's lens direction to any interesting object. This platform is controlled from PC via microcontroller board. But we need a feedback from a photocamera - the image which currently appears on camera's display. Obviously, this feedback is required to be sure that the camera looks in a right direction. At the moment I don't know how to get a single shot image from photocamera by a microcontroller.
Could you please recommend me any directions to dig to ? Any recommendations on how to select photo camera (web cameras are not allowed) ? Any tips ?
Thank you in advance =)
Dwelch is right, you need to pick a "friendly" camera and work from there - google CHDK for a starter.
You could use the SPI interface of a micro to spoof being an SD card, and accept image data from the camera straight into the micro, but you would probably need quite a fast micro with a fair amount of RAM, especially if you want to do any processing on it.
Other than that, you could sample the camera's AV-output (if it has one), either into the micro or straight into the PC via a USB capture stick (or USB capture stick into micro if you're being a show-off), or maybe interrogate the camera over its USB or (insert name of proprietary port here) IO port.
Getting more hacky (yes, even more!) you could sniff the LCD data bus of the camera and steal the image from that, but that brings all sorts of pain, and tiny, tiny screws.
It seems that a lot of small business people have a need for some customized embedded systems, but don't really know too much about the possibilities and cannot quite envisage them.
I had the same problem when trying to explain what Android could do; I was generally met with glazed eyes - and then I made a few demos. Somehow, being able to see something - to be able to touch it and play around with it – people have that cartoon lightbulb moment.
Even if it is not directly applicable to them, a demo starts them thinking about what could be useful to them.
The sort of person I am talking about may or may not be technical, but is certainly intelligent, having built from scratch a business which turns over millions.
Their needs are varied, from RFID or GPS asset & people tracking, to simple stock control systems, displays, communications, sometime satellite, sometimes VPN or LAN (wifi or RJ45). A lot of it needs a good back-end database with a web-site to display, query, data-mine …
So, to get to the question, I am looking for a simple project, or projects, which will cause that cartoon lightbulb moment. It need not be too complicated as those who need complicated solutions are generally tech-savvy, just something straightforward & showing what could be done to streamline their business and make it more profitable.
It would be nice it if could include some wifi/RJ45 comms, communicate across the internet (e.g not just a micro-controller attached to a single PC – that should then communicate with a server/web-site), an RFID reader would be nice, something actually happening (LEDs, sounds, etc), plus some database, database analysis/data-ming – something end-to-end, preferably in both directions.
A friend was suggesting a Rube Goldberg like contraption with a Lego Mindstorms attached to a local PC, but also controllable from a remote PC (representing head office) or web site. That would show remote control of devices. Maybe it could pick up some RFID tags and move them around (at random, or on command), representing stock control (or maybe employee/asset movement within a factory or warehouse (Location Based Services/GIS)), which cold then be shown on the web site, with some nice charts & graphs etc.
Any other ideas?
How best to implement it? One of those micro-controller starter kites like http://www.nerdkits.com/ ? Maybe some Lego, or similar robot kit, a few cheap RFID readers … anything else?
And – the $409,600 question – what's a good, representative demo which demonstrate as many functionalities as possible, as impressively as possible, with the least effort? (keeping it modular and allowing for easy addition of features, since there is such a wide area to cover)
p.s a tie with an Adroid slate PC would be welcome too
Your customers might respond better to a solid looking R/C truck which seeks RFID tags than to a Lego robot. Lego is cool, but it has a bit of a slapped-together 'kiddie' feel.
What if you:
scatter some RFID tags across the conference room.
add a GPS & wifi transmitter to your truck.
drive the truck to the tag
(manually - unless you want to invest a lot of time in steering algorithms).
have a PC drawing a real-time track of the trucks path.
every the truck gets within range of the tag, add it to an inventory list on the screen, showing item id, location, time recorded, total units so far.
indicate the position of the item on the map.
I'd be impressed.
Is it 'least effort'? I don't know, but I'd hope that if this is the type of solution you are pitching, that you already have a good handle on how to read GPS and RFID devices, how to establish a TCP or UDP connection with wifi, how to send and decode packets. Add some simple graphics and database lookup, and you are set.
Regarding hardware, I don't have any first hand experience with any of these, but the GadgetPC Wi-Fi G Kit + a USB RFID reader + a USB GPS reciever looks like a nice platform for experimenting with this.
Many chip manufactures have off-the-shelf demo boards. Microchip has some great demo boards for TCP/IP communications on an embedded system. I haven't seen one yet for RFID. Showing potential customers some of these demos could get them thinking about what is possible.
I'm looking into writing an app that runs as a background process and detects when an app (say, Safari) is playing audio. I can use NSWorkspace to get the process ID's of the currently running applications but I'm at a loss when it comes to detecting what those processes are doing. I assume that there is a way to listen in on a process and detect what public messages the objects are sending. I apologize for my ignorance on the subject.
Has anyone attempted anything like this or are aware of any resources that can help?
I don't think that your "answer" is an answer at all...
and there IS an answer (which is not "42")
your best bet for doing this would be to write a pass-through audio output device. Much like soundflower, actually. so your audio output device would then load the actual (physical) audio output device and pass the audio data along to it directly (after first having a look at the audio stream, of course!). then you only need to convince your users to configure your audio device as the default audio output device so that the majority of applications which play sound will use it automatically. and voila...
your audio processing function will probably just do a quick RMS on the buffer before passing it along to the actual output device. and when the audio power crosses a certain threshold (probably something like -54dB with apple audio hardware), then you know that some app is making sound.
|K<
SoundFlower is an open-source project that allows Mac OS X applications to pass audio to each other. It almost certainly does something similar to what you describe.
I've been informed on another thread that while this is possible, it is an extremely advanced technique and not recommended. It would involve using Application Enhancer (APE) and is considered a not 'nice' thing to do. Looks like that app idea is destined for the big recycling bin in the sky :)