Access the camera flash?

Whitehk · 06-29-2010, 11:56 AM

Hi. I can't figure out how to access the camera flash on the iPhone 4 for my app. Is anyone able to figure this out? I looked through the developer documentation and still can't figure it out. Thanks.

EDIT:When I try to import the <AVFoundation/AVFoundation.h, it's almost as if it doesn't detect it. For instance, I will type AVCaptureDevice in the .h file and it won't recognize it and give me an error. It detects that I've imported some classes (such as the ones that were in 3.0) but not the ones that are new to 4.0 (which one I need).

**JasonR** · 06-29-2010, 01:06 PM

HAve you tried the AVCaptureDevice class? I don't have an iPhone4, so I can't try it, but it looks like the way to go.

Whitehk · 06-29-2010, 02:03 PM

Quote:

Originally Posted by JasonR

HAve you tried the AVCaptureDevice class? I don't have an iPhone4, so I can't try it, but it looks like the way to go.

Yeah. That's the one I was looking at. I'm kind of a newbie and I'm trying to learn how to use the developer documentation. I just couldn't figure out how to implement it.

**JasonR** · 06-29-2010, 02:38 PM

Since you are doing something that's not standard, there's not going to be sample code. So your choice is either try it yourself, or wait until someone else does and posts it. (If you can wait 3-4 weeks, that's when I get my iPhone 4).

If I were you, I would play with the devices array, taking each element and setting flashMode until one of them turned on the flash. IT might look something like this:

Code:

NSArray *devices = [AVCaptureDevice devices];
for (AVCaptureDevice *device in devices) {
     device.flashMode = AVCaptureFlashModeOn;
}

Keep in mind, I'm guessing since I don't have the hardware, but see if that gets you started.

Whitehk · 06-29-2010, 02:42 PM

Quote:

Originally Posted by JasonR

Since you are doing something that's not standard, there's not going to be sample code. So your choice is either try it yourself, or wait until someone else does and posts it. (If you can wait 3-4 weeks, that's when I get my iPhone 4).

If I were you, I would play with the devices array, taking each element and setting flashMode until one of them turned on the flash. IT might look something like this:

Code:

NSArray *devices = [AVCaptureDevice devices];
for (AVCaptureDevice *device in devices) {
     device.flashMode = AVCaptureFlashModeOn;
}

Keep in mind, I'm guessing since I don't have the hardware, but see if that gets you started.

Ok. I will look at it and see if I can get it working. Thanks for your help.

ioiiooo · 06-30-2010, 12:02 AM

Quote:

Originally Posted by Whitehk

Ok. I will look at it and see if I can get it working. Thanks for your help.

Did you end up figuring it out?

harrytheshark · 06-30-2010, 04:59 AM

You need to take a look at AVCaptureSession, AVCaptureDevice, AVCaptureDeviceInput and AVCaptureVideoDataOutput in the documentation.

Everything you need is in there

Whitehk · 06-30-2010, 02:04 PM

Quote:

Originally Posted by ioiiooo

Did you end up figuring it out?

Yes, I found that there was a WWDC session on iTunes over this, so I'm on my way to figuring it out.

Quote:

Originally Posted by harrytheshark

You need to take a look at AVCaptureSession, AVCaptureDevice, AVCaptureDeviceInput and AVCaptureVideoDataOutput in the documentation.

Everything you need is in there

Thanks. Like I said above, I figured this out when I watched the WWDC session.

thecyberduck · 06-30-2010, 02:16 PM

tell us if you find something interesting

mire3212 · 07-05-2010, 12:16 AM

I'm having a very similar problem with trying to access the AVCaptureDevice class. I've imported the AVFoundation.framework into my project and also did an import statement of the AVFoundation/AVFoundation.h, but XCode just keeps saying AVCaptureDevice is undeclared. Also if I look at the header files within the framework itself, it's missing half of the 4.0 specific AVFoundation classes found within the documentation. Any ideas?

Andrew

Tentoxa · 07-08-2010, 02:27 AM

I have the same problem. Who can help us?

I found a free version of a iP4 flashlight:
LED-Light

Works perfect!

mikevh · 07-09-2010, 01:17 AM

Quote:

Originally Posted by Whitehk

Yes, I found that there was a WWDC session on iTunes over this, so I'm on my way to figuring it out.

Thanks. Like I said above, I figured this out when I watched the WWDC session.

Which session?

tavobartientos · 07-09-2010, 04:28 AM

You try your codde on the real iphone 4?

I have one, and my code doesnt work in simulator, but in the iphone4, works....

Tentoxa · 07-09-2010, 08:23 AM

@tavobartientos Could you show us your code, please? I have the same problem adding the AVFoundation.framework. (AVCaptureDevice is undeclared)

darkangelbhv · 07-10-2010, 06:31 AM

Before we can use the flashMode we must use lockForConfiguration.

My Code:

Code:

NSArray* devices = [AVCaptureDevice devices];
AVCaptureDevice* captDevice = nil;
NSLog(@"%d devices found", [devices count]);

for(AVCaptureDevice* device in devices)
{
	if([device hasFlash])
	{
		NSLog(@"device has flash");
		
		
		if ([device isFlashModeSupported:AVCaptureFlashModeOn]) {

			if([device lockForConfiguration:&error])
			{
				device.flashMode = AVCaptureFlashModeOn;
			}
			
		}
	}
}

}

But the flashlight is off :/ What´s wrong ?

Quote:

I have the same problem adding the AVFoundation.framework. (AVCaptureDevice is undeclared)

Test your Code on a iPhone 4. If you run this Code in Simulator it shows this error. If you use a Device it show´s no error

MacBuddy · 07-10-2010, 01:42 PM

I too am having difficulties. I have tried the above methods and just get 2 errors. I came up with this but can't seem to get it to work.

Code:

	AVCaptureSession *captureSession = [[AVCaptureSession alloc] init];
	AVCaptureDevice *videoCaptureDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
	NSError *error = nil;
	AVCaptureDeviceInput *videoInput = [AVCaptureDeviceInput deviceInputWithDevice:videoCaptureDevice error:&error];
	
	if (videoInput) {
		[captureSession addInput:videoInput];
		
		AVCaptureVideoDataOutput* videoOutput = [[AVCaptureVideoDataOutput alloc] init];
		[videoOutput setSampleBufferDelegate:self queue:dispatch_get_current_queue()];
		
		[captureSession addOutput:videoOutput];
		
		[captureSession startRunning];
		
		videoCaptureDevice.torchMode = AVCaptureTorchModeOn;
	}

Any ideas?

EDIT:
It wont compile when building for the sim but builds and runs on my iPhone 4. When I tap the button with this action it returns SIGBART on it. telling me

Code:

videoCaptureDevice.torchMode = AVCaptureTorchModeOn;

this failed.

harrytheshark · 07-10-2010, 02:25 PM

You have to set an output as well as an input for this to work.

MacBuddy · 07-10-2010, 03:18 PM

Quote:

Originally Posted by harrytheshark

You have to set an output as well as an input for this to work.

what do you mean set an output and input?

harrytheshark · 07-10-2010, 03:33 PM

Look in the documentation at AVCaptureSession, you should see an addOutput: method. Follow that through and you'll find what needs to be done

MacBuddy · 07-10-2010, 04:08 PM

Quote:

Originally Posted by harrytheshark

Look in the documentation at AVCaptureSession, you should see an addOutput: method. Follow that through and you'll find what needs to be done

Kay Thanks!

MacBuddy · 07-10-2010, 04:32 PM

Quote:

Originally Posted by harrytheshark

Look in the documentation at AVCaptureSession, you should see an addOutput: method. Follow that through and you'll find what needs to be done

Code:

		AVCaptureSession *captureSession = [[AVCaptureSession alloc] init];
		AVCaptureDevice *videoCaptureDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
		NSError *error = nil;
		AVCaptureDeviceInput *videoInput = [AVCaptureDeviceInput deviceInputWithDevice:videoCaptureDevice error:&error];
		if (videoInput) {
			[captureSession addInput:videoInput];
			
			AVCaptureVideoDataOutput* videoOutput = [[AVCaptureVideoDataOutput alloc] init];
			[videoOutput setSampleBufferDelegate:self queue:dispatch_get_current_queue()];
			
			[captureSession addOutput:videoOutput];
			
			[captureSession startRunning];
			
			videoCaptureDevice.torchMode = AVCaptureTorchModeOn;
		}

Output and Input are their

harrytheshark · 07-10-2010, 05:00 PM

Sorry, I was talking more generally, in regards to your code, you need to run lockForConfiguration and unlockForConfiguration before and after changing device properties.

Code:

[videoCaptureDevice lockForConfiguration:nil];
videoCaptureDevice.torchMode = AVCaptureTorchModeOn;
[videoCaptureDevice unlockForConfiguration];

crivoli · 07-11-2010, 11:34 PM

Anyone get the LED flash to turn on yet?

I have tried all of these suggestions and got nothing to turn on. All of the calls work without errors and the flash modes are tuned on but nothing happens.

Any success for anyone?

agentBangla · 07-12-2010, 02:10 AM

A question which is a little out of topic; do anyone know how can I set the video encoding format as H264 when recording video using AVCaptureSession, AVCaptureInput and AVCaptureOutput?

harrytheshark · 07-12-2010, 02:49 AM

Quote:

Originally Posted by crivoli

Anyone get the LED flash to turn on yet?

I have tried all of these suggestions and got nothing to turn on. All of the calls work without errors and the flash modes are tuned on but nothing happens.

Any success for anyone?

Yeah, I've managed it.