ios - 从 Adob​​eLabsUXMagicSelectionView (Adobe Creative SDK) 获取前景

Question

我正在尝试使用 AdobeLabsUXMagicSelectionView我面临两个问题。我想使用以下两种方法“剪切”选定区域(前景):

方法一)getForeground:andMatte:它没有给我正确的前景。当我选择一个区域并调用getForeground:andMatte我给了我前景和背景(混合)。

选择狗的脸


剪狗的脸


文档说:

Alternatively, if you don’t need to process the underlying bitmap directly, and intend to use the results as inputs to CoreGraphics or CoreImage, you can call:

方法2)在此之后，我试图像文档一样“剪切”

extension AdobeLabsUXMagicSelectionView {

    func foregroundCGImage() -> CGImage {
        let w = size_t(self.image.size.width)
        let h = size_t(self.image.size.height)
        let data = UnsafeMutablePointer<UInt8>(malloc(4 * w * h * sizeof(UInt8)))
        self.readForegroundAndMatteIntoBuffer(data)

        for var i = 0; i < 4 * w * h; i += 4 {
            let alpha: UInt8 = UInt8(data[i + 3]) / 255
            data[i] *= alpha
            data[i + 1] *= alpha
            data[i + 2] *= alpha
        }

        let bitmapInfo = CGBitmapInfo(rawValue: CGImageAlphaInfo.NoneSkipLast.rawValue)
        let ctx = CGBitmapContextCreate(data, w, h, 8, 4 * w, CGColorSpaceCreateDeviceRGB(), bitmapInfo.rawValue)
        let imageRef = CGBitmapContextCreateImage(ctx)!

        return imageRef
    }

}

但它只绘制(黑色)图像的未选择部分(背景)。

任何人都可以帮忙吗？我想要的是获得选定区域的最终图像。

更新:

正如@DonWoodward 所说，我创建了这个类别:

@implementation AdobeLabsUXMagicSelectionView (Foreground)

- (UIImage *)getForeground {
    // show the results
    // first create a UIImage of just the foreground bits per the documentation in AdobeLabsUXMagicSelectionView.h
    size_t w = self.image.size.width;
    size_t h = self.image.size.height;

    uint8_t *data = (uint8_t *)malloc(4*w*h*sizeof(uint8_t));
    [self readForegroundAndMatteIntoBuffer:data];

    // Paint the non-selected portion of the image black
    for (int i = 0; i < 4*w*h; i += 4) {
        float alpha = (float)data[i + 3] / 255;
        data[i    ] *= alpha;
        data[i + 1] *= alpha;
        data[i + 2] *= alpha;
    }
    CGContextRef ctx = CGBitmapContextCreate(data, w, h, 8, 4*w, CGColorSpaceCreateDeviceRGB(), (CGBitmapInfo)kCGImageAlphaNoneSkipLast);
    CGImageRef imageRef = CGBitmapContextCreateImage(ctx);
    UIImage * foregroundBits = [UIImage imageWithCGImage:imageRef];
    CGImageRelease(imageRef);

    return foregroundBits;
}

@end

但是结果在“前景”周围有很多黑色像素。




我需要的？获得一个“干净”的前景(没有黑色像素的选定区域)放在 UIImageView 上

Answer 1

我认为问题在于您的比例因子类型为 uint8_t所以你将比例因子剪裁为零。让它成为一个 float ，它应该工作。这是来自 MagicPuppy(在 objective-c 中)的代码:

    // show the results
    // first create a UIImage of just the foreground bits per the documentation in AdobeLabsUXMagicSelectionView.h
    size_t w = _magicSelectionView.image.size.width;
    size_t h = _magicSelectionView.image.size.height;

    uint8_t *data = (uint8_t *)malloc(4*w*h*sizeof(uint8_t));
    [_magicSelectionView readForegroundAndMatteIntoBuffer:data];

    // Paint the non-selected portion of the image black
    for (int i = 0; i < 4*w*h; i += 4)
    {
        float alpha = (float)data[i + 3] / 255;
        data[i    ] *= alpha;
        data[i + 1] *= alpha;
        data[i + 2] *= alpha;
    }
    CGContextRef ctx = CGBitmapContextCreate(data, w, h, 8, 4*w, CGColorSpaceCreateDeviceRGB(), (CGBitmapInfo)kCGImageAlphaNoneSkipLast);
    CGImageRef imageRef = CGBitmapContextCreateImage(ctx);
    UIImage * foregroundBits = [UIImage imageWithCGImage:imageRef];
    CGImageRelease(imageRef);

    // show the results
    _resultsView = [[UIImageView alloc] initWithFrame: CGRectMake(0, VIEW_Y_OFFSET, self.view.bounds.size.width, self.view.bounds.size.height-VIEW_Y_OFFSET)];
    _resultsView.contentMode = UIViewContentModeScaleAspectFit;
    [_resultsView setImage: foregroundBits];
    [self.view addSubview: _resultsView];