通过编辑 EXIF 数据保存（覆盖）我的 jpg 文件答案

【问题标题】：Save (override) my jpg file with editing EXIF data通过编辑 EXIF 数据保存（覆盖）我的 jpg 文件
【发布时间】：2021-03-13 07:34:48
【问题描述】：

我打开并编辑我的 jpg 文件中的 EXIF（或 TIFF...）数据。请帮助我用编辑数据保存（覆盖）我的 jpg 文件。使用这个简单的代码：

let fileURL = URL(fileURLWithPath: "/Users/test/Pictures/IMG_2808.jpg")

if let imageSource = CGImageSourceCreateWithURL(fileURL as CFURL, nil) {
    var imageProperties = CGImageSourceCopyPropertiesAtIndex(imageSource, 0, nil) as Dictionary?
    let exifDict = imageProperties?[kCGImagePropertyExifDictionary]

    if let UserComment = exifDict?[kCGImagePropertyExifUserComment] ?? nil {
        print("kCGImagePropertyExifUserComment: \(UserComment)")
    }
    else {
        exifDict!.setValue("My comment...", forKey: kCGImagePropertyExifUserComment as String)
        imageProperties![kCGImagePropertyExifDictionary] = exifDict
        
//      What I should do in the next step for update and override my jpg file on disk?
//      Maybe this is not nice way for this realisation? Please help
//
    }
}

【问题讨论】：

见stackoverflow.com/questions/52810822/…

标签： swift image save jpeg exif

【解决方案1】：

经过一番测试，我找到了解决方案：

let fileURL = URL(fileURLWithPath: "/Users/test/Pictures/IMG_2808.jpg")

if let imageSource = CGImageSourceCreateWithURL(fileURL as CFURL, nil) {
    var imageProperties = CGImageSourceCopyPropertiesAtIndex(imageSource, 0, nil) as Dictionary?
    let exifDict = imageProperties?[kCGImagePropertyExifDictionary]

    if let UserComment = exifDict?[kCGImagePropertyExifUserComment] ?? nil {
        print("kCGImagePropertyExifUserComment: \(UserComment)")
    }
    else {
        exifDict!.setValue("My comment...", forKey: kCGImagePropertyExifUserComment as String)
        imageProperties![kCGImagePropertyExifDictionary] = exifDict
     
        if let imageDestination = CGImageDestinationCreateWithURL(fileURL as CFURL, kUTTypeJPEG, 1, nil) {

            CGImageDestinationAddImageFromSource(imageDestination, imageSource, 0, imageProperties as CFDictionary?)

            CGImageDestinationFinalize(imageDestination)
        }
    }
}

我不知道这个解决方案是否正确，但它确实有效！如果您知道更完善的方式，请发表评论

【讨论】：