find设备的相机分辨率的方法iOS
什么是最好的方法来find图像分辨率将被捕获使用设置AVCaptureSessionPresetPhoto 。
我正在尝试在捕捉图像之前find分辨率。
捕捉图像之前，可能没有办法直接获取相机分辨率。
苹果为各种设备和预设提供了一个表格：
捕捉静止图像
以下是支持iOS 9的设备上所有经过testing的相机sessionPreset的表格
+-----------------------+--------------+---------------------------------+---------------+ | 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 | +-----------------------+--------------+---------------------------------+---------------+
码
+ (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; }
使用下面的函数，您可以在捕获开始之前以编程方式从activeFormat获取分辨率，但在添加input和输出之前不需要： 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 }
可以这样做：
/* 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); }
尝试下面的代码来获得最大的设备相机的图像分辨率：
- (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: %dx %d", res.width, res.height); res = [self getCameraMaxStillImageResolution:AVCaptureDevicePositionFront]; NSLog(@" Front Camera max Image resolution: %dx %d", res.width, res.height); }