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デバイスのカメラ解像度iOSを見つける方法

AVCaptureSessionPresetPhotoの設定を使用してキャプチャされる画像解像度を見つけるための最良の方法は何ですか。
画像をキャプチャする前に解像度を見つけようとしています。

18
thar_bun

以下の関数を使用すると、キャプチャを開始する前にプログラムでactiveFormatから解像度を取得できますが、入力と出力を追加する前ではありません。 https://developer.Apple.com/library/ios/documentation/ AVFoundation/Reference/AVCaptureDevice_Class/index.html#// Apple_ref/occ/instp/AVCaptureDevice/activeFormat

private func getCaptureResolution() -> CGSize {
    // Define default resolution
    var resolution = CGSize(width: 0, height: 0)

    // Get cur video device
    let curVideoDevice = useBackCamera ? backCameraDevice : frontCameraDevice

    // Set if video portrait orientation
    let portraitOrientation = orientation == .Portrait || orientation == .PortraitUpsideDown

    // Get video dimensions
    if let formatDescription = curVideoDevice?.activeFormat.formatDescription {
        let dimensions = CMVideoFormatDescriptionGetDimensions(formatDescription)
        resolution = CGSize(width: CGFloat(dimensions.width), height: CGFloat(dimensions.height))
        if portraitOrientation {
            resolution = CGSize(width: resolution.height, height: resolution.width)
        }
    }

    // Return resolution
    return resolution
}
14
Crashalot

以下は、iOS 9をサポートする、デバイス上でテストされたすべてのカメラsessionPresetの表です。

+-----------------------+--------------+---------------------------------+---------------+
|        Device         |    Camera    |     AVCaptureSessionPreset      |  Resolution   |
+-----------------------+--------------+---------------------------------+---------------+
| iPhone 4S             | FRONT        |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 640x480       |
|                       |              | AVCaptureSessionPresetHigh      | 640x480       |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | not supported |
|                       |              | AVCaptureSessionPreset1920x1080 | not supported |
|                       | BACK         |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 3264x2448     |
|                       |              | AVCaptureSessionPresetHigh      | 1920x1080     |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | 1280x720      |
|                       |              | AVCaptureSessionPreset1920x1080 | 1920x1080     |
+-----------------------+--------------+---------------------------------+---------------+
| iPhone 5/5C/5S/6/6+   |              |                                 |               |
|                       | FRONT        |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 1280x960      |
|                       |              | AVCaptureSessionPresetHigh      | 1280x720      |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | 1280x720      |
|                       |              | AVCaptureSessionPreset1920x1080 | not supported |
|                       | BACK         |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 3264x2448     |
|                       |              | AVCaptureSessionPresetHigh      | 1920x1080     |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | 1280x720      |
|                       |              | AVCaptureSessionPreset1920x1080 | 1920x1080     |
+-----------------------+--------------+---------------------------------+---------------+
| iPhone 6S/6S          |              |                                 |               |
|                       | FRONT camera |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 1280x960      |
|                       |              | AVCaptureSessionPresetHigh      | 1280x720      |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | 1280x720      |
|                       |              | AVCaptureSessionPreset1920x1080 | not supported |
|                       | BACK camera  |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 4032x3024     |
|                       |              | AVCaptureSessionPresetHigh      | 1920x1080     |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | 1280x720      |
|                       |              | AVCaptureSessionPreset1920x1080 | 1920x1080     |
+-----------------------+--------------+---------------------------------+---------------+
| iPad 2                |              |                                 |               |
|                       | FRONT        |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 640x480       |
|                       |              | AVCaptureSessionPresetHigh      | 640x480       |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | not supported |
|                       |              | AVCaptureSessionPreset1920x1080 | not supported |
|                       | BACK         |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 960x720       |
|                       |              | AVCaptureSessionPresetHigh      | 1280x720      |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | 1280x720      |
|                       |              | AVCaptureSessionPreset1920x1080 | not supported |
+-----------------------+--------------+---------------------------------+---------------+
| iPad 3                |              |                                 |               |
|                       | FRONT        |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 640x480       |
|                       |              | AVCaptureSessionPresetHigh      | 640x480       |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | not supported |
|                       |              | AVCaptureSessionPreset1920x1080 | not supported |
|                       | BACK         |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 2592x1936     |
|                       |              | AVCaptureSessionPresetHigh      | 1920x1080     |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | 1280x720      |
|                       |              | AVCaptureSessionPreset1920x1080 | 1920x1080     |
+-----------------------+--------------+---------------------------------+---------------+
| iPad 4/Air            |              |                                 |               |
| iPad Mini 1/2/3       |              |                                 |               |
| iPod 5G               |              |                                 |               |
|                       | FRONT        |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 1280x960      |
|                       |              | AVCaptureSessionPresetHigh      | 1280x720      |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | 1280x720      |
|                       |              | AVCaptureSessionPreset1920x1080 | not supported |
|                       | BACK         |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 2592x1936     |
|                       |              | AVCaptureSessionPresetHigh      | 1920x1080     |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | 1280x720      |
|                       |              | AVCaptureSessionPreset1920x1080 | 1920x1080     |
+-----------------------+--------------+---------------------------------+---------------+
| iPad Air 2            |              |                                 |               |
| iPad Mini 4           |              |                                 |               |
| iPad Pro              |              |                                 |               |
|                       | FRONT        |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 1280x960      |
|                       |              | AVCaptureSessionPresetHigh      | 1280x720      |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | 1280x720      |
|                       |              | AVCaptureSessionPreset1920x1080 | not supported |
|                       | BACK         |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 3264x2448     |
|                       |              | AVCaptureSessionPresetHigh      | 1920x1080     |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | 1280x720      |
|                       |              | AVCaptureSessionPreset1920x1080 | 1920x1080     |
+-----------------------+--------------+---------------------------------+---------------+
| iPod Touch 5          |              |                                 |               |
|                       | FRONT        |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 1280x960      |
|                       |              | AVCaptureSessionPresetHigh      | 1280x720      |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | 1280x720      |
|                       |              | AVCaptureSessionPreset1920x1080 | not supported |
|                       | BACK         |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 2592x1936     |
|                       |              | AVCaptureSessionPresetHigh      | 1920x1080     |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | 1280x720      |
|                       |              | AVCaptureSessionPreset1920x1080 | 1920x1080     |
+-----------------------+--------------+---------------------------------+---------------+
| iPod Touch 6          |              |                                 |               |
|                       | FRONT        |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 1280x960      |
|                       |              | AVCaptureSessionPresetHigh      | 1280x720      |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | 1280x720      |
|                       |              | AVCaptureSessionPreset1920x1080 | not supported |
|                       | BACK         |                                 |               |
|                       |              | AVCaptureSessionPresetPhoto     | 3264x2448     |
|                       |              | AVCaptureSessionPresetHigh      | 1920x1080     |
|                       |              | AVCaptureSessionPresetMedium    | 480x360       |
|                       |              | AVCaptureSessionPresetLow       | 192x144       |
|                       |              | AVCaptureSessionPreset640x480   | 640x480       |
|                       |              | AVCaptureSessionPreset1280x720  | 1280x720      |
|                       |              | AVCaptureSessionPreset1920x1080 | 1920x1080     |
+-----------------------+--------------+---------------------------------+---------------+

[〜#〜]コード[〜#〜]

+ (NSDictionary*) cameraResolutions {
    NSString* deviceModel = [self deviceModel];

    // iPhone 4S
    if ([deviceModel isEqualToString:@"iPhone4,1"]) {

        NSString* lFrontCam = @"640x480,480x360,192x144";
        NSString* lBackCam = @"3264x2448,1920x1080,1280x720,640x480,480x360,192x144";
        NSDictionary* lCamResolutions = @{@"front":lFrontCam,
                                          @"back":lBackCam};
        return lCamResolutions;
    }
    // iPhone 5/5C/5S/6/6+/iPod 6
    else if ([deviceModel isEqualToString:@"iPhone5,1"]
             || [deviceModel isEqualToString:@"iPhone5,2"]
             || [deviceModel isEqualToString:@"iPhone5,3"]
             || [deviceModel isEqualToString:@"iPhone5,4"]
             || [deviceModel isEqualToString:@"iPhone6,1"]
             || [deviceModel isEqualToString:@"iPhone6,2"]
             || [deviceModel isEqualToString:@"iPhone7,1"]
             || [deviceModel isEqualToString:@"iPhone7,2"]
             || [deviceModel isEqualToString:@"iPod7,1"]) {

        NSString* lFrontCam = @"1280x960,1280x720,640x480,480x360,192x144";
        NSString* lBackCam = @"3264x2448,1920x1080,1280x720,640x480,480x360,192x144";
        NSDictionary* lCamResolutions = @{@"front":lFrontCam,
                                          @"back":lBackCam};
        return lCamResolutions;
    }
    // iPhone 6S/6S+
    else if ([deviceModel isEqualToString:@"iPhone8,1"]
             || [deviceModel isEqualToString:@"iPhone8,2"]) {
        NSString* lFrontCam = @"1280x960,1280x720,640x480,480x360,192x144";
        NSString* lBackCam = @"4032x3024,1920x1080,1280x720,640x480,480x360,192x144";
        NSDictionary* lCamResolutions = @{@"front":lFrontCam,
                                          @"back":lBackCam};
        return lCamResolutions;
    }
    // iPad 2
    else if ([deviceModel isEqualToString:@"iPad2,1"]
             || [deviceModel isEqualToString:@"iPad2,2"]
             || [deviceModel isEqualToString:@"iPad2,3"]
             || [deviceModel isEqualToString:@"iPad2,4"]) {


        NSString* lFrontCam = @"640x480,480x360,192x144";
        NSString* lBackCam = @"1280x720,960x720,480x360,192x144,640x480";
        NSDictionary* lCamResolutions = @{@"front":lFrontCam,
                                          @"back":lBackCam};
        return lCamResolutions;
    }
    // iPad 3
    else if ([deviceModel isEqualToString:@"iPad3,1"]
             || [deviceModel isEqualToString:@"iPad3,2"]
             || [deviceModel isEqualToString:@"iPad3,3"]) {


        NSString* lFrontCam = @"640x480,480x360,192x144";
        NSString* lBackCam = @"2592x1936,1920x1080,1280x720,640x480,480x360,192x144";
        NSDictionary* lCamResolutions = @{@"front":lFrontCam,
                                          @"back":lBackCam};
        return lCamResolutions;
    }
    // iPad 4/Air/Mini/Mini 2/Mini 3/iPod 5G
    else if ([deviceModel isEqualToString:@"iPad3,4"]
             || [deviceModel isEqualToString:@"iPad3,5"]
             || [deviceModel isEqualToString:@"iPad3,6"]
             || [deviceModel isEqualToString:@"iPad4,1"]
             || [deviceModel isEqualToString:@"iPad4,2"]
             || [deviceModel isEqualToString:@"iPad4,3"]
             || [deviceModel isEqualToString:@"iPad4,4"]
             || [deviceModel isEqualToString:@"iPad4,5"]
             || [deviceModel isEqualToString:@"iPad4,6"]
             || [deviceModel isEqualToString:@"iPad4,7"]
             || [deviceModel isEqualToString:@"iPad4,8"]
             || [deviceModel isEqualToString:@"iPod5,1"]) {

        NSString* lFrontCam = @"1280x960,1280x720,640x480,480x360,192x144";
        NSString* lBackCam = @"2592x1936,1920x1080,1280x720,640x480,480x360,192x144";
        NSDictionary* lCamResolutions = @{@"front":lFrontCam,
                                           @"back":lBackCam};
        return lCamResolutions;
    }
    // iPad Air 2/Mini 4/Pro
    else if ([deviceModel isEqualToString:@"iPad5,3"]
             || [deviceModel isEqualToString:@"iPad5,4"]) {
        NSString* lFrontCam = @"1280x960,1280x720,640x480,480x360,192x144";
        NSString* lBackCam = @"3264x2448,1920x1080,1280x720,640x480,480x360,192x144";
        NSDictionary* lCamResolutions = @{@"front":lFrontCam,
                                          @"back":lBackCam};
        return lCamResolutions;
    }
    return nil;
}
102
Roman Slyepko

直接プログラムでカメラの解像度を取得する前に(== --- ==)取得する方法はおそらくありません画像。

Appleは、さまざまなデバイスとプリセットの表を提供しています。

静止画像のキャプチャ

8
CouchDeveloper

この方法で行うことができます:

/* Callback that is called when you activate the capture session. */
- (void) avCaptureInputPortFormatDescriptionDidChangeNotification:(NSNotification *)notification {
        CMFormatDescriptionRef formatDescription = nil;
        NSArray *ports = [deviceInput ports];
        AVCaptureInputPort *usePort = nil;

        for (AVCaptureInputPort *port in ports) {
                if (usePort == nil || [port.mediaType isEqualToString:AVMediaTypeVideo]) {
                        usePort = port;
                        break;
                }
        }

        if (usePort != nil)
                formatDescription = usePort.formatDescription;
        if (formatDescription != nil) {
                /*------------>>>>>>> THIS IS YOUR RESOLUTION */
                CMVideoDimensions dimensions = CMVideoFormatDescriptionGetDimensions(formatDescription);
                self.frameSize = CGSizeMake(dimensions.width, dimensions.height);
                [[NSNotificationCenter defaultCenter] removeObserver:self];
                NSLog(@"Capturing with %dx%d", (int)self.frameSize.width, (int)self.frameSize.height);
        } else {
                NSLog(@"Failed to detect resolution, using default one.");
                self.frameSize = CGSizeMake(640.0f, 480.0f);
        }
}

- (id) init {
        if ((self = [super init])) {
                /* Default framesize. */
                self.frameSize = CGSizeMake(640.0f, 480.0f);

                AVCaptureSession *capSession = [[AVCaptureSession alloc] init];
                /* -------->>>>>>> REQUESTED RESOLUTION, CAN BE SOMTHING ELSE */
                [capSession setSessionPreset:AVCaptureSessionPresetHigh];

//                if (([modelName rangeOfString:@"iPhone 5"].length != 0) || ([modelName rangeOfString:@"iPhone 6"].length != 0)) {
//                        [capSession setSessionPreset:AVCaptureSessionPresetHigh];
//                } else {
//                        [capSession setSessionPreset:AVCaptureSessionPreset640x480];
//                }
//                
                self.captureSession = capSession;

                [[NSNotificationCenter defaultCenter] addObserver:self
                                                         selector:@selector(avCaptureInputPortFormatDescriptionDidChangeNotification:)
                                                             name:AVCaptureInputPortFormatDescriptionDidChangeNotification object:nil];
        }
        return self;
}

- (void) dealloc
{
        [[NSNotificationCenter defaultCenter] removeObserver:self];
        if (self.captureSession.isRunning)
                [self.captureSession stopRunning];
        self.captureSession = nil;
}

- (void) addRawViewOutput
{
    /* We setup the output */
    AVCaptureVideoDataOutput *captureOutput = [[AVCaptureVideoDataOutput alloc] init];

        /* While a frame is processes in -captureOutput:didOutputSampleBuffer:fromConnection: delegate methods
           no other frames are added in the queue.
       If you don't want this behaviour set the property to NO */
    captureOutput.alwaysDiscardsLateVideoFrames = YES;

        /*We specify a minimum duration for each frame (play with this settings to avoid having too many frames waiting
     in the queue because it can cause memory issues). It is similar to the inverse of the maximum framerate.
     In this example we set a min frame duration of 1/10 seconds so a maximum framerate of 10fps. We say that
     we are not able to process more than 10 frames per second.*/
    //captureOutput.minFrameDuration = CMTimeMake(1, 10);

    /*We create a serial queue to handle the processing of our frames*/
    dispatch_queue_t queue;
    queue = dispatch_queue_create("com.YourApp.cameraQueue", NULL);
    [captureOutput setSampleBufferDelegate:self queue:queue];
//  dispatch_release(queue);

    // Set the video output to store frame in BGRA (It is supposed to be faster)
    NSString *key = (NSString*)kCVPixelBufferPixelFormatTypeKey;
    NSNumber *value = [NSNumber numberWithUnsignedInt:kCVPixelFormatType_32BGRA];
    NSDictionary *videoSettings = [NSDictionary dictionaryWithObject:value forKey:key];
    [captureOutput setVideoSettings:videoSettings];

        // Register an output
    [self.captureSession addOutput:captureOutput];
}

- (bool) startWithDevicePosition:(AVCaptureDevicePosition)devicePosition
{
        AVCaptureDevice *videoDevice = [self cameraWithPosition:devicePosition];

        if (!videoDevice)
                return FALSE;

        NSError *error;

        AVCaptureDeviceInput *videoIn = [AVCaptureDeviceInput deviceInputWithDevice:videoDevice error:&error];
        self.deviceInput = videoIn;

        if (!error)
        {
                if ([[self captureSession] canAddInput:videoIn])
                {
                        [[self captureSession] addInput:videoIn];
                }
                else
                {
                        NSLog(@"Couldn't add video input");
                        return FALSE;
                }
        }
        else
        {
                NSLog(@"Couldn't create video input");
                return FALSE;
        }

        [self addRawViewOutput];
        [self resume];
        return TRUE;
}

-(void) pause
{
        self.paused = YES;
        if (self.captureSession.isRunning)
                [captureSession stopRunning];
}

-(void) resume
{
        if (!self.captureSession.isRunning)
                [captureSession startRunning];
        self.paused = NO;
}

#pragma mark -
#pragma mark AVCaptureSession delegate
- (void)captureOutput:(AVCaptureOutput *)captureOutput
didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer
       fromConnection:(AVCaptureConnection *)connection
{
        CVImageBufferRef imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);

        /* Lock the image buffer */
        CVPixelBufferLockBaseAddress(imageBuffer,0);

        /* Get information about the image */
        uint8_t *baseAddress = (uint8_t *)CVPixelBufferGetBaseAddress(imageBuffer);
        size_t width = CVPixelBufferGetWidth(imageBuffer);
        size_t height = CVPixelBufferGetHeight(imageBuffer);
        size_t stride = CVPixelBufferGetBytesPerRow(imageBuffer);
        size_t size = CVPixelBufferGetDataSize(imageBuffer);

        BGRAVideoFrame frame = {(int)width, (int)height, (int)stride, (int)size, baseAddress};
        [delegate frameReady:frame];

        /* We unlock the image buffer */
        CVPixelBufferUnlockBaseAddress(imageBuffer,0);
}
1

デバイスカメラの最大画像解像度を取得するには、次のコードを試してください。

- (CMVideoDimensions) getCameraMaxStillImageResolution:(AVCaptureDevicePosition) cameraPosition {

    CMVideoDimensions max_resolution;
    max_resolution.width = 0;
    max_resolution.height = 0;

    AVCaptureDevice *captureDevice = nil;

    NSArray *devices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
    for (AVCaptureDevice *device in devices) {
        if ([device position] == cameraPosition) {
            captureDevice = device;
            break;
        }
    }
    if (captureDevice == nil) {
        return max_resolution;
    }

    NSArray* availFormats=captureDevice.formats;

    for (AVCaptureDeviceFormat* format in availFormats) {
        CMVideoDimensions resolution = format.highResolutionStillImageDimensions;
        int w = resolution.width;
        int h = resolution.height;
        if ((w * h) > (max_resolution.width * max_resolution.height)) {
            max_resolution.width = w;
            max_resolution.height = h;
        }
    }

    return max_resolution;
}

- (void) printCamerasInfo {
    CMVideoDimensions res;
    res = [self getCameraMaxStillImageResolution:AVCaptureDevicePositionBack];
    NSLog(@" Back  Camera max Image resolution: %d x %d", res.width, res.height);
    res = [self getCameraMaxStillImageResolution:AVCaptureDevicePositionFront];
    NSLog(@" Front Camera max Image resolution: %d x %d", res.width, res.height);
}
1