我认为您有点误解了编码参数的用法。如果要指定编码“二进制”，则需要一致地进行编码。但实际上您根本不需要它。您似乎对Buffer和二进制字符串的用法感到困惑。
// This tells node to load the file into a Buffer 'original_data' because you// have not specified an encoding for the returned values. If you provided an// encoding, then original_data would be a string with that encoding.fs.readFile(image_origial, function(err, original_data){ // This tells node to take that buffer, and write it to the new filename. // Again no encoding is provided, so it will assume a Buffer or utf8 string. fs.writeFile('image_orig.jpg', original_data, function(err) {}); // This tells node to create a new buffer from the old buffer, which means // it will iterate over original_data copying the bytes one at a time. But // they will be identical buffers. It will ignore the 'binary' argument // since the object you are passing isn't a string. // Then it enpres the content of that Buffer to base64, which is fine. var base64Image = new Buffer(original_data, 'binary').toString('base64'); // Here you depre the base64 to a buffer, which is fine, but then you // convert the buffer into a string with encoding 'binary'. This means that // it is a string object whose pre points are bytes of the buffer. var depredImage = new Buffer(base64Image, 'base64').toString('binary'); // Here you try to write that String object to a file. Since the argument you // have given is a string and you have not given an encoding argument for the // write command, then it will assume that 'utf8' is the encoding. It will try to // depre your binary string into a utf8 enpred buffer, and write that buffer. // This will cause it to fail because that encoding conversion is wrong. // Really through, 'binary' is just wrong to use. Buffers are already binary. fs.writeFile('image_depred.jpg', depredImage, function(err) {});});下一个示例将起作用，但是效率很低，因为不需要一直更改编码，但是我只是想表明它是清楚的。如果您真的DID想要使用特定的编码，则需要确保您保持一致。这些功能中的每一个都有一个编码参数。
fs.readFile(image_origial, 'binary', function(err, original_data){ fs.writeFile('image_orig.jpg', original_data, 'binary', function(err) {}); var base64Image = new Buffer(original_data, 'binary').toString('base64'); var depredImage = new Buffer(base64Image, 'base64').toString('binary'); fs.writeFile('image_depred.jpg', depredImage, 'binary', function(err) {});});这是正确的方法。将所有内容保留为Buffer，除非将其设为base64。
fs.readFile(image_origial, function(err, original_data){ fs.writeFile('image_orig.jpg', original_data, function(err) {}); var base64Image = original_data.toString('base64'); var depredImage = new Buffer(base64Image, 'base64'); fs.writeFile('image_depred.jpg', depredImage, function(err) {});});
