如何从ALAsset获取exif信息？

Question

我需要从选定资产中获取exif信息，并将其一部分显示在屏幕上。

Answer 1

[[asset defaultRepresentation] metadata];

返回给定资产表示形式的元数据词典字典。 请查看此词典中是否有您感兴趣的数据。我不确定，但是我认为该词典（和子词典）中的键与CGImageProperties Reference中列出的键相同。

Answer 2

这是一个完整的答案。。。

NSDictionary *nsd = [[asset3 defaultRepresentation] metadata];
    NSString *widthStr = [nsd objectForKey: @"PixelWidth"];
    NSString *heightStr = [nsd objectForKey: @"PixelHeight"];

    NSLog(@"nsd: %@ ... widthStr: %@ ... heightStr: %@ ...", nsd, widthStr, heightStr);

输出：

nsd: {
    ColorModel = RGB;
    DPIHeight = 72;
    DPIWidth = 72;
    Depth = 8;
    Orientation = 1;
    PixelHeight = 1136;
    PixelWidth = 642;
    "{Exif}" =     {
        ColorSpace = 1;
        ComponentsConfiguration =         (
            1,
            2,
            3,
            0
        );
        ExifVersion =         (
            2,
            2,
            1
        );
        FlashPixVersion =         (
            1,
            0
        );
        PixelXDimension = 642;
        PixelYDimension = 1136;
        SceneCaptureType = 0;
    };
    "{TIFF}" =     {
        Orientation = 1;
        ResolutionUnit = 2;
        XResolution = 72;
        YResolution = 72;
    };
} ... widthStr: 642 ... heightStr: 1136 ...