我为iOS使用opencv 2.4.9，需要帮助。
我想在拍摄高分辨率照片时用CVVideoCamera捕捉。我需要用于过程图像方法的摄像机，以通过边缘检测添加成熟的文档捕获。这也很好用，但是一旦检测到文档，我就需要一张已识别的高分辨率文档照片。
我发现了这个http://code.opencv.org/svn/gsoc2012/ios/trunk/HelloWorld_iOS/HelloWorld_iOS/VideoCameraController.m
这可以同时处理照片和视频，但是过程镜像方法与cvvideocamera委托(delegate)的方法不同，而我的算法不适用于此类:-/
但是我在OpenCV中搜索此photocamera / videocamera解决方案以获取CVVideoCamera。
希望获得帮助，对不起我的英语
最佳答案
我解决了这个问题，在cvVideoCamera类中添加了cvPhotoCamera类的一些方法。它对我有用，但可能需要一些改进才能应用于您的代码。
CvPhotoCameraMod.h:
#import <UIKit/UIKit.h>
#import <opencv2/highgui/cap_ios.h>
#import <opencv2/highgui/ios.h>
#define DEGREES_RADIANS(angle) ((angle) / 180.0 * M_PI)
@class CvPhotoCameraMod;
@protocol CvPhotoCameraDelegateMod <CvPhotoCameraDelegate>
- (void)processImage:(cv::Mat&)image;
@end
@interface CvPhotoCameraMod : CvPhotoCamera <AVCaptureVideoDataOutputSampleBufferDelegate>
@property (nonatomic, retain) CALayer *customPreviewLayer;
@property (nonatomic, retain) AVCaptureVideoDataOutput *videoDataOutput;
@property (nonatomic, weak) id <CvPhotoCameraDelegateMod> delegate;
- (void)createCustomVideoPreview;
@end
CvPhotoCameraMod.mm:
#import "CvPhotoCameraMod.h"
#import <CoreGraphics/CoreGraphics.h>
#define DEGREES_RADIANS(angle) ((angle) / 180.0 * M_PI)
@implementation CvPhotoCameraMod
-(void)createCaptureOutput;
{
[super createCaptureOutput];
[self createVideoDataOutput];
}
- (void)createCustomVideoPreview;
{
[self.parentView.layer addSublayer:self.customPreviewLayer];
}
//Method mostly taken from this source: https://github.com/Itseez/opencv/blob/b46719b0931b256ab68d5f833b8fadd83737ddd1/modules/videoio/src/cap_ios_video_camera.mm
-(void)createVideoDataOutput{
// Make a video data output
self.videoDataOutput = [AVCaptureVideoDataOutput new];
//Drop grayscale support here
self.videoDataOutput.videoSettings = [NSDictionary dictionaryWithObject:[NSNumber numberWithUnsignedInt:kCVPixelFormatType_32BGRA] forKey:(id)kCVPixelBufferPixelFormatTypeKey];
// discard if the data output queue is blocked (as we process the still image)
[self.videoDataOutput setAlwaysDiscardsLateVideoFrames:YES];
if ( [self.captureSession canAddOutput:self.videoDataOutput] ) {
[self.captureSession addOutput:self.videoDataOutput];
}
[[self.videoDataOutput connectionWithMediaType:AVMediaTypeVideo] setEnabled:YES];
// set video mirroring for front camera (more intuitive)
if ([self.videoDataOutput connectionWithMediaType:AVMediaTypeVideo].supportsVideoMirroring) {
if (self.defaultAVCaptureDevicePosition == AVCaptureDevicePositionFront) {
[self.videoDataOutput connectionWithMediaType:AVMediaTypeVideo].videoMirrored = YES;
} else {
[self.videoDataOutput connectionWithMediaType:AVMediaTypeVideo].videoMirrored = NO;
}
}
// set default video orientation
if ([self.videoDataOutput connectionWithMediaType:AVMediaTypeVideo].supportsVideoOrientation) {
[self.videoDataOutput connectionWithMediaType:AVMediaTypeVideo].videoOrientation = self.defaultAVCaptureVideoOrientation;
}
// create a custom preview layer
self.customPreviewLayer = [CALayer layer];
self.customPreviewLayer.bounds = CGRectMake(0, 0, self.parentView.frame.size.width, self.parentView.frame.size.height);
self.customPreviewLayer.position = CGPointMake(self.parentView.frame.size.width/2., self.parentView.frame.size.height/2.);
// create a serial dispatch queue used for the sample buffer delegate as well as when a still image is captured
// a serial dispatch queue must be used to guarantee that video frames will be delivered in order
// see the header doc for setSampleBufferDelegate:queue: for more information
dispatch_queue_t videoDataOutputQueue = dispatch_queue_create("VideoDataOutputQueue", DISPATCH_QUEUE_SERIAL);
[self.videoDataOutput setSampleBufferDelegate:self queue:videoDataOutputQueue];
}
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection
{
(void)captureOutput;
(void)connection;
if (self.delegate) {
// convert from Core Media to Core Video
CVImageBufferRef imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
CVPixelBufferLockBaseAddress(imageBuffer, 0);
void* bufferAddress;
size_t width;
size_t height;
size_t bytesPerRow;
CGColorSpaceRef colorSpace;
CGContextRef context;
int format_opencv;
OSType format = CVPixelBufferGetPixelFormatType(imageBuffer);
if (format == kCVPixelFormatType_420YpCbCr8BiPlanarFullRange) {
format_opencv = CV_8UC1;
bufferAddress = CVPixelBufferGetBaseAddressOfPlane(imageBuffer, 0);
width = CVPixelBufferGetWidthOfPlane(imageBuffer, 0);
height = CVPixelBufferGetHeightOfPlane(imageBuffer, 0);
bytesPerRow = CVPixelBufferGetBytesPerRowOfPlane(imageBuffer, 0);
} else { // expect kCVPixelFormatType_32BGRA
format_opencv = CV_8UC4;
bufferAddress = CVPixelBufferGetBaseAddress(imageBuffer);
width = CVPixelBufferGetWidth(imageBuffer);
height = CVPixelBufferGetHeight(imageBuffer);
bytesPerRow = CVPixelBufferGetBytesPerRow(imageBuffer);
}
// delegate image processing to the delegate
cv::Mat image((int)height, (int)width, format_opencv, bufferAddress, bytesPerRow);
CGImage* dstImage;
if ([self.delegate respondsToSelector:@selector(processImage:)]) {
[self.delegate processImage:image];
}
// check if matrix data pointer or dimensions were changed by the delegate
bool iOSimage = false;
if (height == (size_t)image.rows && width == (size_t)image.cols && format_opencv == image.type() && bufferAddress == image.data && bytesPerRow == image.step) {
iOSimage = true;
}
// (create color space, create graphics context, render buffer)
CGBitmapInfo bitmapInfo;
// basically we decide if it's a grayscale, rgb or rgba image
if (image.channels() == 1) {
colorSpace = CGColorSpaceCreateDeviceGray();
bitmapInfo = kCGImageAlphaNone;
} else if (image.channels() == 3) {
colorSpace = CGColorSpaceCreateDeviceRGB();
bitmapInfo = kCGImageAlphaNone;
if (iOSimage) {
bitmapInfo |= kCGBitmapByteOrder32Little;
} else {
bitmapInfo |= kCGBitmapByteOrder32Big;
}
} else {
colorSpace = CGColorSpaceCreateDeviceRGB();
bitmapInfo = kCGImageAlphaPremultipliedFirst;
if (iOSimage) {
bitmapInfo |= kCGBitmapByteOrder32Little;
} else {
bitmapInfo |= kCGBitmapByteOrder32Big;
}
}
if (iOSimage) {
context = CGBitmapContextCreate(bufferAddress, width, height, 8, bytesPerRow, colorSpace, bitmapInfo);
dstImage = CGBitmapContextCreateImage(context);
CGContextRelease(context);
} else {
NSData *data = [NSData dataWithBytes:image.data length:image.elemSize()*image.total()];
CGDataProviderRef provider = CGDataProviderCreateWithCFData((__bridge CFDataRef)data);
// Creating CGImage from cv::Mat
dstImage = CGImageCreate(image.cols, // width
image.rows, // height
8, // bits per component
8 * image.elemSize(), // bits per pixel
image.step, // bytesPerRow
colorSpace, // colorspace
bitmapInfo, // bitmap info
provider, // CGDataProviderRef
NULL, // decode
false, // should interpolate
kCGRenderingIntentDefault // intent
);
CGDataProviderRelease(provider);
}
// render buffer
dispatch_sync(dispatch_get_main_queue(), ^{
self.customPreviewLayer.contents = (__bridge id)dstImage;
});
// cleanup
CGImageRelease(dstImage);
CGColorSpaceRelease(colorSpace);
CVPixelBufferUnlockBaseAddress(imageBuffer, 0);
}
}
@end