调用 CGContextDrawImage 后内存泄漏

问：

我已经阅读了所有 CGContextDrawImage 内存峰值答案，我尝试过，但还没有任何解决方案有效。

这是我的代码，调用CGContextDrawImage后，内存增加10-40MB。我正在使用此代码从图像生成视频，如果我有 200 张图像，应用程序就会崩溃。

循环访问图像：

for(UIImage * img in imageArray)
{

    buffer = [self pixelBufferFromCGImage:[img CGImage] ImageSize:img.size];

    BOOL append_ok = NO;
    int j = 0;
    while (!append_ok) {
        if (adaptor.assetWriterInput.readyForMoreMediaData)  {
            //print out status:
            NSLog(@"Processing video frame (%d,%lu)",frameCount,(unsigned long)[imageArray count]);

            CMTime frameTime = CMTimeMake(frameCount*frameDuration,(int32_t) fps);
            append_ok = [adaptor appendPixelBuffer:buffer withPresentationTime:frameTime];
            if(!append_ok){
                NSError *error = videoWriter.error;
                if(error!=nil) {
                    NSLog(@"Unresolved error %@,%@.", error, [error userInfo]);
                }
            }
        }
        else {
            printf("adaptor not ready %d, %d\n", frameCount, j);
            [NSThread sleepForTimeInterval:0.1];
        }
    }
    if (!append_ok) {
        printf("error appending image %d times %d\n, with error.", frameCount, j);
    }
    frameCount++;
}

下面是 pixelBufferFromCGImage 函数

- (CVPixelBufferRef) pixelBufferFromCGImage: (CGImageRef) image ImageSize:(CGSize)size {

NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:
                         [NSNumber numberWithBool:YES], kCVPixelBufferCGImageCompatibilityKey,
                         [NSNumber numberWithBool:YES], kCVPixelBufferCGBitmapContextCompatibilityKey,
                         nil];
CVPixelBufferRef pxbuffer = NULL;

CVReturn status = CVPixelBufferCreate(kCFAllocatorDefault,
                                      size.width,
                                      size.height,
                                      kCVPixelFormatType_32ARGB,
                                      (__bridge CFDictionaryRef) options,
                                      &pxbuffer);
if (status != kCVReturnSuccess){
    NSLog(@"Failed to create pixel buffer");
}

CVPixelBufferLockBaseAddress(pxbuffer, 0);
void *pxdata = CVPixelBufferGetBaseAddress(pxbuffer);

CGColorSpaceRef rgbColorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = CGBitmapContextCreate(pxdata, size.width,
                                             size.height, 8, 4*size.width, rgbColorSpace,
                                             kCGImageAlphaPremultipliedFirst);
//kCGImageAlphaNoneSkipFirst);
CGContextConcatCTM(context, CGAffineTransformMakeRotation(0));
CGContextDrawImage(context, CGRectMake(0, 0, CGImageGetWidth(image),
                                       CGImageGetHeight(image)), image);
CGColorSpaceRelease(rgbColorSpace);
CGContextRelease(context);
CVPixelBufferUnlockBaseAddress(pxbuffer, 0);
return pxbuffer;
}