1

我正在开发一个应用程序，我在其中记录了主屏幕并被SetNeedsDisplay method使用。

但问题是它需要大量内存，即使我没有录制屏幕。

我想减少下面提到的代码的内存使用量。

有什么解决办法吗？

提前致谢。

- (void) drawRect:(CGRect)rect
{
    NSDate* start = [NSDate date];
    CGContextRef context = [self createBitmapContextOfSize:self.frame.size];
    //NSLog(@"context value %@",context);
    //not sure why this is necessary...image renders upside-down and mirrored
    CGAffineTransform flipVertical = CGAffineTransformMake(1, 0, 0, -1, 0, self.frame.size.height);
    CGContextConcatCTM(context, flipVertical);

    [self.layer renderInContext:context];

    CGImageRef cgImage = CGBitmapContextCreateImage(context);
    UIImage* background = [UIImage imageWithCGImage: cgImage];
    CGImageRelease(cgImage);
    self.currentScreen = background;

    if (_recording) {
        float millisElapsed = [[NSDate date] timeIntervalSinceDate:startedAt] * 1000.0;
        [self writeVideoFrameAtTime:CMTimeMake((int)millisElapsed, 1000)];
    }

    float processingSeconds = [[NSDate date] timeIntervalSinceDate:start];
    delayRemaining = (1.0 / self.frameRate) - processingSeconds;

    //redraw at the specified framerate
    [self performSelector:@selector(setNeedsDisplay) withObject:nil afterDelay:delayRemaining > 0.0 ? delayRemaining : 0.01];
}

 -(CGContextRef) createBitmapContextOfSize:(CGSize) size 
{

    CGContextRef    context = NULL;
    CGColorSpaceRef colorSpace;
    int             bitmapByteCount;
    int             bitmapBytesPerRow;

    bitmapBytesPerRow   = (size.width * 4);
    bitmapByteCount     = (bitmapBytesPerRow * size.height);
    colorSpace = CGColorSpaceCreateDeviceRGB();
    if (bitmapData != NULL) {
        free(bitmapData);
    }
    bitmapData = malloc( bitmapByteCount );
    if (bitmapData == NULL) {
        fprintf (stderr, "Memory not allocated!");
        return NULL;
    }

    context = CGBitmapContextCreate (bitmapData,
                                     size.width,
                                     size.height,
                                     8,      // bits per component
                                     bitmapBytesPerRow,
                                     colorSpace,
                                     kCGImageAlphaNoneSkipFirst);

    CGContextSetAllowsAntialiasing(context,NO);
    if (context== NULL) {
        free (bitmapData);
        fprintf (stderr, "Context not created!");
        return NULL;
    }
    CGColorSpaceRelease( colorSpace );

    return context;
}
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1 回答 1

2

您每帧创建一个上下文，但从不释放它，尝试将其添加到末尾：

CGContextRelease(context);
于 2013-03-28T14:21:00.647 回答