我正在使用GPUImage库函数来操纵CVPixelbuffer的高度和宽度。我正在以纵向录制视频,当用户旋转设备时,我的屏幕将自身调整为横向模式。我希望横向框架在屏幕上适合宽高比。
例如: - 我在纵向模式320x568中启动视频,当我将设备转为横向时,我的画面是568x320,我想要适合320x568。为了调整这个东西,我想操纵CVPixelBuffer。但这会占用大量内存,最后我的应用程序崩溃了。
- (CVPixelBufferRef) GPUImageCreateResizedSampleBufferWithBuffer:(CVPixelBufferRef)cameraFrame withBuffer:(CGSize)finalSize withSampleBuffer:(CMSampleBufferRef)sampleBuffer
{
CVPixelBufferRef pixel_buffer = NULL;
// CVPixelBufferCreateWithPlanarBytes for YUV input
@autoreleasepool {
CGSize originalSize = CGSizeMake(CVPixelBufferGetWidth(cameraFrame), CVPixelBufferGetHeight(cameraFrame));
CVPixelBufferLockBaseAddress(cameraFrame, 0);
GLubyte *sourceImageBytes = (GLubyte *)CVPixelBufferGetBaseAddress(cameraFrame);
CGDataProviderRef dataProvider = CGDataProviderCreateWithData(NULL, sourceImageBytes, CVPixelBufferGetBytesPerRow(cameraFrame) * originalSize.height, NULL);
CGColorSpaceRef genericRGBColorspace = CGColorSpaceCreateDeviceRGB();
CGImageRef cgImageFromBytes = CGImageCreate((int)originalSize.width, (int)originalSize.height, 8, 32, CVPixelBufferGetBytesPerRow(cameraFrame), genericRGBColorspace, kCGBitmapByteOrder32Little | kCGImageAlphaPremultipliedFirst, dataProvider, NULL, NO, kCGRenderingIntentDefault);
GLubyte *imageData = (GLubyte *) calloc(1, ((int)finalSize.width * (int)finalSize.height * 4));
CGContextRef imageContext = CGBitmapContextCreate(imageData, (int)finalSize.width, (int)finalSize.height, 8, (int)finalSize.width * 4, genericRGBColorspace, kCGBitmapByteOrder32Little | kCGImageAlphaPremultipliedFirst);
CGRect scaledRect = AVMakeRectWithAspectRatioInsideRect(originalSize, CGRectMake(0, 0, finalSize.width, finalSize.height));
CGContextDrawImage(imageContext, scaledRect, cgImageFromBytes);
CGImageRelease(cgImageFromBytes);
CGContextRelease(imageContext);
CGColorSpaceRelease(genericRGBColorspace);
CGDataProviderRelease(dataProvider);
CVPixelBufferCreateWithBytes(kCFAllocatorDefault, finalSize.width, finalSize.height, kCVPixelFormatType_32BGRA, imageData, finalSize.width * 4, stillImageDataReleaseCallback, NULL, NULL, &pixel_buffer);
CMVideoFormatDescriptionRef videoInfo = NULL;
CMVideoFormatDescriptionCreateForImageBuffer(NULL, pixel_buffer, &videoInfo);
CMTime frameTime = CMTimeMake(1, 30);
CMSampleTimingInfo timing = {frameTime, frameTime, kCMTimeInvalid};
CMSampleBufferCreateForImageBuffer(kCFAllocatorDefault, pixel_buffer, YES, NULL, NULL, videoInfo, &timing, &sampleBuffer);
CVPixelBufferUnlockBaseAddress(cameraFrame, 0);
CFRelease(videoInfo);
// CVPixelBufferRelease(pixel_buffer);
}
return pixel_buffer;
}
答案 0 :(得分:0)
CG * - CoreGraphics使用CPU并且对于实时视频而言太慢,使用CV *和GPU
// - (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection
CVPixelBufferLockBaseAddress(pixelBuffer, kCVPixelBufferLock_ReadOnly);
CIImage *baseImg = [CIImage imageWithCVPixelBuffer:pixelBuffer];
CIImage *resultImg = [baseImg imageByCroppingToRect:outputFrameCropRect];
resultImg = [resultImg imageByApplyingTransform:outputFrameTransform];
// created once
// glCtx = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES2];
// ciContext = [CIContext contextWithEAGLContext:glCtx options:@{kCIContextWorkingColorSpace:[NSNull null]}];
// ciContextColorSpace = CGColorSpaceCreateDeviceRGB();
// CVReturn res = CVPixelBufferPoolCreatePixelBuffer(kCFAllocatorDefault, VTCompressionSessionGetPixelBufferPool(compressionSession), &finishPixelBuffer);
[ciContext render:resultImg toCVPixelBuffer:finishPixelBuffer bounds:resultImg.extent colorSpace:ciContextColorSpace];
CVPixelBufferUnlockBaseAddress(pixelBuffer, kCVPixelBufferLock_ReadOnly);