使用 Dynamsoft Mobile Barcode SDK 的 iOS 条形码扫描仪
节省时间和金钱。使用 Dynamsoft 条码阅读器 SDK 加速 iOS 条码应用程序的开发。
引言
Dynamsoft 致力于为所有主流平台提供条码 SDK。目前，它已涵盖桌面平台的 Windows、Linux 和 macOS。对于移动平台，Dynamsoft 已经发布了移动 iOS 条码 SDK。无论您更喜欢免费软件还是专有软件，这都是一个全新的选择。在下面的段落中，我们将向您展示如何使用 iOS 条码 SDK。
Dynamsoft iOS 条码阅读器的特性
兼容性
- iOS 7.0 或更高版本
- Xcode 6.0 或更高版本
输入数据
- UIImage 或 NV21
支持的 1D/2D 条码类型
- 1D：Code 39, Code 93, Code 128, Codabar, EAN-8, EAN-13, UPC-A, UPC-E, Interleaved 2 of 5 (ITF), Industrial 2 of 5 (Code 2 of 5 Industry, Standard 2 of 5, Code 2 of 5), ITF-14
- 2D：QRCode, DataMatrix 和 PDF417
检测到的条码信息
- 条码类型
- 条码值（字符串形式）
- 条码原始数据（字节形式）
- 条码边界矩形
- 四个角的坐标
iOS 条码扫描器示例
打开 Xcode 7 并按下 Shift+Command+N 创建一个使用 Single View Application 模板的新项目。
将 DynamsoftBarcodeReader.framework 拖到您的项目中。 选中“如果需要则复制项目”选项
该框架将被复制到您的项目文件夹中。您需要这样做吗？ 打开项目属性并选择 Build Settings > Search Paths
如果您没有将框架复制到您的项目中，您需要更改 Framework Search Path。 否则，它将无法找到该框架。
添加依赖项。 选择 Build Phases > Link Binary With Libraries 以添加 DynamsoftBarcodeReader.framework 和 libc++.tbd(Xcode 6 的 libc++.dylib)
在 ViewDidLoad 中创建一个 DbrManager 实例
- (void)viewDidLoad {
[super viewDidLoad];
[[UIApplication sharedApplication] setIdleTimerDisabled: YES];
//register notification for UIApplicationDidBecomeActiveNotification
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(didBecomeActive:)
name:UIApplicationDidBecomeActiveNotification
object:nil];
//init DbrManager with Dynamsoft Barcode Reader mobile license
dbrManager = [[DbrManager alloc] initWithLicense:@"<license>"];
[dbrManager setRecognitionCallback:self :@selector(onReadImageBufferComplete:)];
[dbrManager beginVideoSession];
[self configInterface];
}
使用有效的许可证初始化 Dynamsoft 条码阅读器
-(id)initWithLicense:(NSString *)license{
self = [super init];
if(self)
{
m_videoCaptureSession = nil;
m_barcodeReader = [[BarcodeReader alloc] initWithLicense:license];
isPauseFramesComing = NO;
isCurrentFrameDecodeFinished = YES;
barcodeFormat = [Barcode UNKNOWN];
startRecognitionDate = nil;
m_recognitionReceiver = nil;
}
return self;
}
使用后置摄像头作为捕获设备
-(AVCaptureDevice *)getAvailableCamera {
NSArray *videoDevices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
AVCaptureDevice *captureDevice = nil;
for (AVCaptureDevice *device in videoDevices) {
if (device.position == AVCaptureDevicePositionBack) {
captureDevice = device;
break;
}
}
if (!captureDevice)
captureDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
return captureDevice;
}
创建一个视频捕获会话
-(void)beginVideoSession {
AVCaptureDevice *inputDevice = [self getAvailableCamera];
AVCaptureDeviceInput *captureInput = [AVCaptureDeviceInput
deviceInputWithDevice:inputDevice
error:nil];
AVCaptureVideoDataOutput *captureOutput = [[AVCaptureVideoDataOutput alloc] init];
captureOutput.alwaysDiscardsLateVideoFrames = YES;
dispatch_queue_t queue;
queue = dispatch_queue_create("dbrCameraQueue", NULL);
[captureOutput setSampleBufferDelegate:self queue:queue];
// Enable continuous autofocus
if ([inputDevice isFocusModeSupported:AVCaptureFocusModeContinuousAutoFocus]) {
NSError *error = nil;
if ([inputDevice lockForConfiguration:&error]) {
inputDevice.focusMode = AVCaptureFocusModeContinuousAutoFocus;
[inputDevice unlockForConfiguration];
}
}
// Enable AutoFocusRangeRestriction
if([inputDevice respondsToSelector:@selector(isAutoFocusRangeRestrictionSupported)] &&
inputDevice.autoFocusRangeRestrictionSupported) {
if([inputDevice lockForConfiguration:nil]) {
inputDevice.autoFocusRangeRestriction = AVCaptureAutoFocusRangeRestrictionNear;
[inputDevice unlockForConfiguration];
}
}
[captureOutput setVideoSettings:[NSDictionary dictionaryWithObject:[NSNumber numberWithInt:kCVPixelFormatType_420YpCbCr8BiPlanarFullRange] forKey:(id)kCVPixelBufferPixelFormatTypeKey]];
if(captureInput == nil || captureOutput == nil)
{
return;
}
m_videoCaptureSession = [[AVCaptureSession alloc] init];
[m_videoCaptureSession addInput:captureInput];
[m_videoCaptureSession addOutput:captureOutput];
if ([m_videoCaptureSession canSetSessionPreset:AVCaptureSessionPreset1920x1080])
{
[m_videoCaptureSession setSessionPreset :AVCaptureSessionPreset1920x1080];
cameraResolution.width = 1920;
cameraResolution.height = 1080;
}
else if ([m_videoCaptureSession canSetSessionPreset:AVCaptureSessionPreset1280x720])
{
[m_videoCaptureSession setSessionPreset :AVCaptureSessionPreset1280x720];
cameraResolution.width = 1280;
cameraResolution.height = 720;
}
else if([m_videoCaptureSession canSetSessionPreset:AVCaptureSessionPreset640x480])
{
[m_videoCaptureSession setSessionPreset :AVCaptureSessionPreset640x480];
cameraResolution.width = 640;
cameraResolution.height = 480;
}
[m_videoCaptureSession startRunning];
}
在预览层上显示视频
AVCaptureSession* captureSession = [dbrManager getVideoSession];
if(captureSession == nil)
return;
previewLayer = [AVCaptureVideoPreviewLayer layerWithSession:captureSession];
[previewLayer setVideoGravity:AVLayerVideoGravityResizeAspectFill];
previewLayer.frame = mainScreenLandscapeBoundary;
cameraPreview = [[UIView alloc] init];
[cameraPreview.layer addSublayer:previewLayer];
[self.view insertSubview:cameraPreview atIndex:0];
根据环境亮度，切换闪光灯
- (void) turnFlashOn: (BOOL) on {
// validate whether flashlight is available
Class captureDeviceClass = NSClassFromString(@"AVCaptureDevice");
if (captureDeviceClass != nil) {
AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
if (device != nil && [device hasTorch] && [device hasFlash]){
[device lockForConfiguration:nil];
if (on == YES) {
[device setTorchMode:AVCaptureTorchModeOn];
[device setFlashMode:AVCaptureFlashModeOn];
[flashButton setImage:[UIImage imageNamed:@"flash_on"] forState:UIControlStateNormal];
[flashButton setTitle:NSLocalizedString(@"flash-on", @"flash on string") forState:UIControlStateNormal];
} else {
[device setTorchMode:AVCaptureTorchModeOff];
[device setFlashMode:AVCaptureFlashModeOff];
[flashButton setImage:[UIImage imageNamed:@"flash_off"] forState:UIControlStateNormal];
[flashButton setTitle:NSLocalizedString(@"flash-off", @"flash off string") forState:UIControlStateNormal];
}
[device unlockForConfiguration];
}
}
}
保持相机自动对焦
if ([inputDevice isFocusModeSupported:AVCaptureFocusModeContinuousAutoFocus]) {
NSError *error = nil;
if ([inputDevice lockForConfiguration:&error]) {
inputDevice.focusMode = AVCaptureFocusModeContinuousAutoFocus;
[inputDevice unlockForConfiguration];
}
}
if([inputDevice respondsToSelector:@selector(isAutoFocusRangeRestrictionSupported)] &&
inputDevice.autoFocusRangeRestrictionSupported) {
if([inputDevice lockForConfiguration:nil]) {
inputDevice.autoFocusRangeRestriction = AVCaptureAutoFocusRangeRestrictionNear;
[inputDevice unlockForConfiguration];
}
}
使用 AVCaptureVideoDataOutputSampleBufferDelegate 接收捕获的视频，并在 captureOutput 中读取条码
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection;
{
@autoreleasepool {
if(isPauseFramesComing == YES || isCurrentFrameDecodeFinished == NO) return;
isCurrentFrameDecodeFinished = NO;
void *imageData = NULL;
uint8_t *copyToAddress;
CVImageBufferRef imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
OSType pixelFormat = CVPixelBufferGetPixelFormatType(imageBuffer);
if (!(pixelFormat == '420v' || pixelFormat == '420f'))
{
isCurrentFrameDecodeFinished = YES;
return;
}
CVPixelBufferLockBaseAddress(imageBuffer, 0);
int numPlanes = (int)CVPixelBufferGetPlaneCount(imageBuffer);
int bufferSize = (int)CVPixelBufferGetDataSize(imageBuffer);
int imgWidth = (int)CVPixelBufferGetWidthOfPlane(imageBuffer, 0);
int imgHeight = (int)CVPixelBufferGetHeightOfPlane(imageBuffer, 0);
if(numPlanes < 1)
{
isCurrentFrameDecodeFinished = YES;
return;
}
uint8_t *baseAddress = (uint8_t *) CVPixelBufferGetBaseAddressOfPlane(imageBuffer, 0);
size_t bytesToCopy = CVPixelBufferGetHeightOfPlane(imageBuffer, 0) * CVPixelBufferGetBytesPerRowOfPlane(imageBuffer, 0);
imageData = malloc(bytesToCopy);
copyToAddress = (uint8_t *) imageData;
memcpy(copyToAddress, baseAddress, bytesToCopy);
CVPixelBufferUnlockBaseAddress(imageBuffer, 0);
NSData *buffer = [NSData dataWithBytesNoCopy:imageData length:bufferSize freeWhenDone:YES];
startRecognitionDate = [NSDate date];
// read frame using Dynamsoft Barcode Reader in async manner
[m_barcodeReader readSingleAsync:buffer width:imgWidth height:imgHeight barcodeFormat: barcodeFormat sender:m_recognitionReceiver onComplete:m_recognitionCallback];
}
}
应用下载
您可以从 iTunes App Store 安装该应用。
获取 iOS 条码 SDK
您想快速开发 iOS 条码应用程序吗？ 现在就开始动手吧
支持
如果您对上述示例或 iOS 条码 SDK 有任何疑问，请随时联系 support@dynamsoft.com。