2010-10-17 85 views
3

我正在使用Apple的AVCaptureSession示例代码,并且创建的UIImage完全是空白的。这只是发生在iPhone 3G,具有独特的错误显示出来的控制台,上面写着沿 -仅在iPhone 3G上返回空白图像的AVCaptureSession

Error: CGDataProviderCreateWithCopyOfData: vm_copy failed: status 2.

我在网上研究了错误,发现这个StackOverflow answer,它摆脱了错误的...但图像仍然是空白的。

有没有其他人经历过这一点,并知道如何解决它?

在此先感谢。

我的代码 -

CVImageBufferRef imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer); 
CVPixelBufferLockBaseAddress(imageBuffer, 0); 

void *baseAddress = CVPixelBufferGetBaseAddress(imageBuffer); 
size_t bytesPerRow = CVPixelBufferGetBytesPerRow(imageBuffer); 
size_t width = CVPixelBufferGetWidth(imageBuffer); 
size_t height = CVPixelBufferGetHeight(imageBuffer); 

CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB(); 

CGContextRef context = CGBitmapContextCreate(baseAddress, width, height, 8, bytesPerRow, colorSpace, kCGBitmapByteOrder32Little | kCGImageAlphaPremultipliedFirst); 
CGImageRef quartzImage = CGBitmapContextCreateImage(context); 
CVPixelBufferUnlockBaseAddress(imageBuffer,0); 

CGContextRelease(context); 
CGColorSpaceRelease(colorSpace); 

UIImage *image = [UIImage imageWithCGImage:quartzImage]; 

CGImageRelease(quartzImage); 

return image; 

回答

6

东西API在时髦所以周围的工作,我使用的是:

//void *baseAddress = CVPixelBufferGetBaseAddress(imageBuffer);  
size_t bytesPerRow = CVPixelBufferGetBytesPerRow(imageBuffer);  
size_t width = CVPixelBufferGetWidth(imageBuffer);  
size_t height = CVPixelBufferGetHeight(imageBuffer);  

// vm_copy fails on older model phones...  
//  
uint8_t *baseAddress = malloc(bytesPerRow * height);  
memcpy(baseAddress, CVPixelBufferGetBaseAddress(imageBuffer), bytesPerRow * height); 

CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();  

// NO ALPHA CHANNEL ON OLDER MODELS  
// CGContextRef context = CGBitmapContextCreate(baseAddress, width, height, 8, bytesPerRow, colorSpace, kCGBitmapByteOrder32Little | kCGImageAlphaPremultipliedFirst);  
CGContextRef context = CGBitmapContextCreate(baseAddress, width, height, 8, bytesPerRow, colorSpace, kCGBitmapByteOrder32Little | kCGImageAlphaNoneSkipFirst);  
CGImageRef quartzImage = CGBitmapContextCreateImage(context);  

CVPixelBufferUnlockBaseAddress(imageBuffer,0);  
CGContextRelease(context);  
CGColorSpaceRelease(colorSpace);  
free(baseAddress); 

UIImage *image = [UIImage imageWithCGImage:quartzImage];  
CGImageRelease(quartzImage); 

return image;