我正在开发一个小型项目,该项目将被包含在一个新项目中。它基本上是一个测试单元。
我的做法是创建一个AVCaptureSession,然后创建一个OutputSampleBufferDelegate方法。在这个方法中,我将sampleBuffer转换为UIImage并保存UIImage。当我在我的iPhone 4上运行应用程序时,它每秒只能保存2-3张图像。肯定有更有效的方法来保存图像。
有人可以帮我加速吗?
谢谢! 代码大部分来自此处
我的做法是创建一个AVCaptureSession,然后创建一个OutputSampleBufferDelegate方法。在这个方法中,我将sampleBuffer转换为UIImage并保存UIImage。当我在我的iPhone 4上运行应用程序时,它每秒只能保存2-3张图像。肯定有更有效的方法来保存图像。
有人可以帮我加速吗?
谢谢! 代码大部分来自此处
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection
{
UIImage *resultUIImage = [self imageFromSampleBuffer:sampleBuffer];
NSData *imageData = [NSData dataWithData:UIImagePNGRepresentation(resultUIImage)];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *path = [paths objectAtIndex:0];
CMTime frameTime = CMSampleBufferGetPresentationTimeStamp(sampleBuffer);
NSString *filename = [NSString stringWithFormat:@"%f.png", CMTimeGetSeconds(frameTime)];
NSString *finalPath = [path stringByAppendingString:filename];
[imageData writeToFile:finalPath atomically:YES];
}
// Create a UIImage from sample buffer data
- (UIImage *)imageFromSampleBuffer:(CMSampleBufferRef)sampleBuffer
{
// Get a CMSampleBuffer's Core Video image buffer for the media data
CVImageBufferRef imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
// Lock the base address of the pixel buffer
CVPixelBufferLockBaseAddress(imageBuffer, 0);
// Get the number of bytes per row for the pixel buffer
void *baseAddress = CVPixelBufferGetBaseAddress(imageBuffer);
// Get the number of bytes per row for the pixel buffer
size_t bytesPerRow = CVPixelBufferGetBytesPerRow(imageBuffer);
// Get the pixel buffer width and height
size_t width = CVPixelBufferGetWidth(imageBuffer);
size_t height = CVPixelBufferGetHeight(imageBuffer);
// Create a device-dependent RGB color space
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
// Create a bitmap graphics context with the sample buffer data
CGContextRef context = CGBitmapContextCreate(baseAddress, width, height, 8, bytesPerRow, colorSpace, kCGBitmapByteOrder32Little | kCGImageAlphaPremultipliedFirst);
// Create a Quartz image from the pixel data in the bitmap graphics context
CGImageRef quartzImage = CGBitmapContextCreateImage(context);
// Unlock the pixel buffer
CVPixelBufferUnlockBaseAddress(imageBuffer,0);
// Free up the context and color space
CGContextRelease(context);
CGColorSpaceRelease(colorSpace);
// Create an image object from the Quartz image
UIImage *image = [UIImage imageWithCGImage:quartzImage];
// Release the Quartz image
CGImageRelease(quartzImage);
return image;
}