Is there a universal USB API for smartphones? - usb

Just what the title states - Is there such a thing as a USB framework for smartphones s.a Android, BB, WP?

No there is not. Most platforms will expose part of the device as removable storage so you can transfer files but everything else is custom

Related

Sony Alpha 77M2 Remote control over USB

I have three Sony Alpha 77M2 cameras, and I'm trying to take photos with all three simultaneously, and retrieve these photos. I can do the simultaneous shutter release using commercial remote triggers synced off a single transmitter, and I can control a single camera over USB using the Sony Remote Camera Control software - however this can't control more than one camera, and it won't let me run more than one instance on a single machine.
My question, therefore, is whether there is an API available for the USB remote control interface for these cameras? They don't support the WiFi API, so I can't use that (and WiFi isn't much use for the environment this system will be used in, due to the likelyhood of interference)
It turned out that the camera supports enough of the PTP protocol for libgphoto to recognise it and retrieve the images in tethered mode - but not to control the shutter.

Camera Remote API beta SDK: How to synchronize multiple DSC QX 100 cameras

Can we control multiple DSC-QX100 cameras using the Camera Remote API SDK from an iPad OS7?
The objective is to cause multiple cameras to "snap" picture at the exact same time. Perhaps each camera has an address (serial number)...can the software communicate with all cameras at the same time using multiple addresses? Need is limited to still photos and so-called fast, rapid photography. Video not necessary.
If so, how?
Unfortunately you can only control one QX100 lens at a time. This is because the lens connects over WiFi and you are limited to only a single WiFi connection at once on an iPad. It may be possible using a desktop PC with multiple wireless cards installed but that would be the only way.
As the Sony rep said, there's no way to do this with "officially supported" techniques.
The reason for this is that the camera acts as a WiFi Access Point (AP) - so while multiple devices can connect to it, most mobile devices can only connect to it and not anything else (since iOS and Android don't support connection to multiple APs simultaneously). This is also why you can't use other network interfaces when connected to the camera. (I don't know about iOS, but Android always prioritizes WiFi over cell network data, for example.)
Android devices have a feature called "WiFi Direct" that provides more flexibility in terms of peer-to-peer interconnection, but iOS does not support WFD. The QX100 DOES respond to WFD invites, and you can accept a pairing request with (if I remember correctly) a long-press of the shutter button. However, the official app only supports normal WiFi AP connections.
I have not yet attempted to see if using Sony's remote API in combination with the (unsupported but apparently present) WiFi Direct capability works.
More info on Wifi Direct and Android can be found at http://developer.android.com/guide/topics/connectivity/wifip2p.html
Marlin SONY, I disagree, wifi is Ethernet and by definition can handle multiple devices on the same network. If you run a phone or iPad as a hotspot and connect multiple devices, it works.
Multicam Switcher Basic is an example of a free app that supports cutting together multiple camera angles live. Unfortunately the app is still being developed so features like third party camera support isn't included, but it does show what is possible and awaits development.
I think this should be possible. Apps like CollabraCamâ„¢ (Multicam Social Video Production) or RecoLive MultiCam prove that is possible to use mulitple cams simultaneous.
I need someone too to develop an App to be able to use "two" sony dsc-qx for 3D shoots. Please, if You know how or who can do this contact me email#3-d.re

Why can a SD card be read/write by both the phone and a computer

Some phones carry a SD card and can read/write files on it. If the phone is connected to a computer and placed in mass storage mode, the computer can also read/write files on the SD card as if it's a USB drive. So my question is, how can the computer access a peripheral that belongs to another device (the phone)?
To my understanding, there should be a physical switch in the phone that routes the data buses of the SD card to either the bus of the phone or the micro-USB port? Then there's also a driver that controls this switch? If so, where's such driver (in Android OS or iOS for examples)? If not, what's the mechanism to share this SD card?
Note that I'm not talking about MTP, but the mass storage class. I know that the phone and computer may not be able to access the SD card simultaneously - probably one at a time, depending on the status of USB connection. I'm interested in the mechanism to control/switch the access/connection to the SD card from two hosts.
Comments: The similar mechanism may be found in a mp3 player: when it's plugged into the computer, we can add/remove musics. The mp3 player cannot play musics until it's unplugged from the computer - at least mine is like this. Android OS should do the same but I can't find the related source codes.
To my understanding, there should be a physical switch
No, the switch is in the software.
what's the mechanism to share this SD card?
A piece of the software does the umount of the sdcard and connects
it as a USB Mass storage device to the PC - like a card reader would do.
The Linux kernel itself contains a driver that works as a USB mass storage device, but I don't know whether Android actually uses this.

Detect new video and audio inputs

I want to create application where I can record video with audio and save it to disk.
When application start I detect all video and audio sources and show this list on the UI.
But when I disconnect one of webcams (or unplug mic), this device still remain in list.
How I can get notifications of device connect/disconnect, both for video devices(USB) and audio devices(jack 3.5).
Thank you.
WBR
Maxim
You might find some useful tips in this other question, here IOKit device adding/removal notifications - only fire once?
I also have an example of an app that uses the IOKit framework to detect adding and removing USB devices on my github account here: https://github.com/tjarratt/Panic-Button
Baring that, the apple developer site has a lot of documentation on using USB devices:
https://developer.apple.com/library/mac/documentation/devicedrivers/conceptual/USBBook/USBDeviceInterfaces/USBDevInterfaces.html

Developing an app with Camera Access and GPS

I need to develop a symbian application in which the app is triggered while taking a photo and upload to a web location with the GPS location of the phone. I would like to know which all devices can support this and is there any API restrictions or licence required to do this.
Sorry for the relevant plug but what you are looking for is basically 3 chapters (Networking, Multimedia and Location Based Services) of the Quick Recipes on Symbian OS book.
Since your application will use Networking APIs (and therefore cost the application user money), you will have to go through the Symbian Signed process.
As far as how many Symbian-powered phones contain both a camera and a GPS, I am afraid you are going to need to look at the invidual handset manufacturers websites to come up with an exhaustive list. Outside Japan, they are Nokia, Sony-Ericsson and Samsung.
Here is a list of Nokia models and their info
Here is a list of capabilities and what signing method they need