ios - 释放CGImageRef以避免内存泄漏

Question

我想每秒多次调用图像方法，但出现内存泄漏。

我尝试执行 CFRelease(rawImageRef); 但返回下一个错误:

-[Not A Type retain]: message sent to deallocated instance 0x14dd3770

使用代码更新:

- (CGColorRef)averageColorRect:(CGRect)rect {

    CGImageRef rawImageRef = CGImageCreateWithImageInRect(_imageRaster, rect);

    // This function returns the raw pixel values
    CFDataRef data = CGDataProviderCopyData(CGImageGetDataProvider(rawImageRef));
    const UInt8 *rawPixelData = CFDataGetBytePtr(data);

    NSUInteger imageHeight = CGImageGetHeight(rawImageRef);
    NSUInteger imageWidth  = CGImageGetWidth(rawImageRef);
    NSUInteger bytesPerRow = CGImageGetBytesPerRow(rawImageRef);
    NSUInteger stride = CGImageGetBitsPerPixel(rawImageRef) / 8;

    // Here I sort the R,G,B, values and get the average over the whole image
    unsigned int red   = 0;
    unsigned int green = 0;
    unsigned int blue  = 0;

    for (int row = 0; row < imageHeight; row++) {
        const UInt8 *rowPtr = rawPixelData + bytesPerRow * row;
        for (int column = 0; column < imageWidth; column++) {
            red    += rowPtr[0];
            green  += rowPtr[1];
            blue   += rowPtr[2];
            rowPtr += stride;

        }
    }
    CFRelease(data);

    CGFloat f = 1.0f / (255.0f * imageWidth * imageHeight);
    return [UIColor colorWithRed:f * red  green:f * green blue:f * blue alpha:1].CGColor;

}

Answer 1

你永远不会释放rawImageRef。

我会在释放数据后立即调用CGImageRelease(rawImageRef);。