是否可以通过检测对象的base64编码的变化来检测对象的变化程度。
假设我将文档附件发送给多个用户，每个用户都对其进行了更改并通过电子邮件发回给我，我可以使用原始 Base64 和接收到的 Base64 之间的字符串距离来检测哪个版本的更改最多。这是一个有效的指标吗？
如果没有，是否还有其他指标来量化增量？
Is it possible to detect changes in the base64 encoding of an object to detect the degree of changes in the object.
Suppose I send a document attachment to several users and each makes changes to it and emails back to me, can I use the string distance between original base64 and the received base64s to detect which version has the most changes. Would that be a valid metric?
If not, would there be any other metrics to quantify the deltas?
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这完全取决于您编码的文档的类型。如果它是一个文本文件，那么当然，base64 编码的差异可能与实际更改相同。但是，您可能有一种文件格式，其中内容的更改实际上会产生完全不同的二进制文件。 ZIP 文件就是一个例子。
That would depend entirely on the type of the document you had encoded. If it was a text file, then sure, the base64 encoded difference are probably on a par with the actual changes. However, you may have a format of a file where changes to the contents effectively produce a completely different binary file. An example of this would be a ZIP file.
您应该执行与 diff 相同的操作。然后例如对差异字段大小进行度量。
you should do the same that diff does. Then for example do the metrics on diff fiel size.
从理论上讲，是的，如果进行智能差异（检测插入、删除和修改）。
实际上，不会，除非文档绝对是纯文本。二进制格式无法进行有意义的比较。
In theory, yes, if do a smart diff (detecting inserts, deletions, and modifications).
In practice, no, unless the documents are absolutely plain text. Binary formats can't be meaningfully diff'd.
Base64 将 3x8 位值组打包为 4x6。如果将一个 8 位值更改一位位，则只会影响 6 位值中的一个。如果更改两位，则大约有 5/12 的机会达到其他 6 位值之一。所以如果你计算位数，它是完全等价的；否则，您将根据您使用的指标引入噪音。
Base64 packs groups of 3x8 bit values into 4x6. If you change one 8 bit value by one bit, then you'll impact only one of the 6 bit values. If you change by two bits, then you have about a 5/12 chance of hitting one of the other 6 bit values. So if you're counting bits, it is entirely equivalent; otherwise, you will introduce noise depending on the metric you use.