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Difference in Base64 encoding

I am trying to encode, Image to Base 64 string in AngularJS2
handleFileSelect(evt) {
var files = evt.target.files;
var file = files[0];
if (files && file) {
var reader = new FileReader();
reader.onload = this._handleReaderLoaded.bind(this);
reader.readAsBinaryString(file);
}
}
_handleReaderLoaded(readerEvt) {
var binaryString = readerEvt.target.result;
this.model.UserProfileImageBase64 = btoa(binaryString);
console.log(this.model.UserProfileImage);
}
I am receiving a different string,in compare to encoding it from Java
Base64.encodeToString(getBytesFromBitmap(bitmap),Base64.NO_WRAP);
Any Idea how can we match both Base64 encoding? I had tried same with base64 encoding in angular as well
this.model.UserProfileImageBase64 = Base64.encode(binaryString);
But no dfiference in result.
BtoA and Base64 producing same result and, if I am verifying it online I am getting image as well but I need it in the same format which is generated by Java

I am getting the same result with java and javascript.
With java I did:
byte[] imageBytes = IOUtils.toByteArray(new URL("https://www.w3schools.com/css/paris.jpg"));
String base64 = Base64.getEncoder().encodeToString(imageBytes);
System.out.println(base64);
With javascript I did:
const fileReader: FileReader = new FileReader();
fileReader.readAsDataURL(file);
fileReader.onloadend = () => {
retVal.next(fileReader.result);
};
NOTE: I would suggest not to use readBynaryAsString as it is deprecated and might not work. FileReader
NOTE: That in javascript I wait till the file is uploaded to get the data and I passed to an observable next(...)

changeListener($event) : void {
this.readThis($event.target);
}
readThis(inputValue: any): void {
var file:File = inputValue.files[0];
var myReader:FileReader = new FileReader();
myReader.onloadend = (e) => {
this.image = myReader.result;
}
myReader.readAsDataURL(file);
}
component.html
<input type="file" accept="image/*" (change)="changeListener($event)">
Follow this link Angular 2 encode image to base64

Image Orientation

I have been researching this for a long time.
I need to know how to get an image's orientation by reading it from the metadata tags.
I have looked at Exif, and other 3rd party code. I'am just interested to learn how to do it just from the reading the metadata tags.
I had a code that reads the IIOMetadata but the image dimension tag or orientation will just say normal.
Any suggestions?

https://github.com/exif-js/exif-js/blob/master/exif.js
function base64ToArrayBuffer (base64) {
base64 = base64.replace(/^data\:([^\;]+)\;base64,/gmi, '');
var binaryString = atob(base64);
var len = binaryString.length;
var bytes = new Uint8Array(len);
for (var i = 0; i < len; i++) {
bytes[i] = binaryString.charCodeAt(i);
}
return bytes.buffer;
}
reader.onload = function (e) {
var image = new Image();
image.src = e.target.result;
exif = EXIF.readFromBinaryFile(base64ToArrayBuffer(e.target.result));
console.log(exif.Orientation, exif.Make);

POST multipart/mixed in .NET

Just what the title says, if it helps in any way I have this java code (multipart consists of json object and file):
// Construct a MultiPart
MultiPart multiPart = new MultiPart();
multiPart.bodyPart(new BodyPart(inParams, MediaType.APPLICATION_JSON_TYPE));
multiPart.bodyPart(new BodyPart(fileToUpload, MediaType.APPLICATION_OCTET_STREAM_TYPE));
// POST the request
final ClientResponse clientResp = resource.type("multipart/mixed").post(ClientResponse.class, multiPart);
(using com.sun.jersey.multipart ) and I want to create the same in .NET (C#)
So far I managed to POST the json object like this:
Uri myUri = new Uri("http://srezWebServices/rest/ws0/test");
var httpWebRequest = (HttpWebRequest)WebRequest.Create(myUri);
httpWebRequest.Proxy = null;
httpWebRequest.Accept = "application/json";
httpWebRequest.ContentType = "application/json";
httpWebRequest.Method = "POST";
Console.Write("START!");
using (var streamWriter = new StreamWriter(httpWebRequest.GetRequestStream())){
string json = new JavaScriptSerializer().Serialize(new
{
wsId = "0",
accessId = "101",
accessCode = "x#ds!2"
});
streamWriter.Write(json);
streamWriter.Flush();
streamWriter.Close();
var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();
}
But I want to send the file together. The content type has to be "multipart/mixed" because that's what the web service gets. I tried to find some package that supports multiparts but I found nothing except maybe this http://www.example-code.com/csharp/mime_multipartMixed.asp (which is not free so I can't use it).

I finally managed to do it like this:
HttpContent stringStreamContent = new StringContent(json);
stringStreamContent.Headers.ContentType = new MediaTypeHeaderValue("application/json");
HttpContent fileStreamContent = new StreamContent(fileStream);
fileStreamContent.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");
// Construct a MultiPart
// 1st : JSON Object with IN parameters
// 2nd : Octet Stream with file to upload
var content = new MultipartContent("mixed");
content.Add(stringStreamContent);
content.Add(fileStreamContent);
// POST the request as "multipart/mixed"
var result = client.PostAsync(myUrl, content).Result;

Invalid value for ByteString for Update photo in Google Apps engine in java

I am trying to update photo using Google apps engine.I have imageurl i convert it into byte array and then encode
it using base64.i got encoded string,now i m trying to update photodata using directory API Reference
https://developers.google.com/admin-sdk/directory/v1/reference/users/photos#resource
after update i got error invalid byteString.I face this problem from yesterday.So Let me know where i did wrong? Below is my code.
import com.google.appengine.repackaged.org.apache.commons.codec.binary.Base64;
above class used for Base64.
URL url = new URL(myImageUrl);
ByteArrayOutputStream bais = new ByteArrayOutputStream();
InputStream is = null;
try {
is = url.openStream ();
byte[] byteChunk = new byte[4096]; // Or whatever size you want to read in at a time.
int n;
while ( (n = is.read(byteChunk)) > 0 ) {
bais.write(byteChunk, 0, n);
}
System.out.println(byteChunk);
byte[] encoded = Base64.encodeBase64(byteChunk);
String ecodedString = new String(encoded, "UTF-8");
ecodedString = ecodedString.replace("/", "_");
ecodedString = ecodedString.replace("+", "-");
ecodedString = ecodedString.replace("=", "*");
System.out.println(ecodedString);

Padding could be the problem, try not replacing "=" with "*". See also:
Converting string to web-safe Base64 format
p.s. repackaged libs are discouraged in app engine; you may use DatatypeConverter.printBase64Binary() instead.

How to send binary data from AS3 through Java to a filesystem?

I've got XML data in AS3 that needs to be compressed, validated on my Java Google App Engine servlet then saved to a file in Google Cloud Storage. Later that file will be opened and decompressed by the AS3 client. The process works if I do it with plain XML or text, but if I ByteArray#compress the data, it dies during ByteArray#uncompress with "There was an error decompressing the data".
I've tried setting the content type and mime type at various points, as well as encoding with Base64, but every attempt seems to break in a different way and I never get the same XML back that I sent in. Do I need to use multipart? Should I compress on the server? What's the best practice for doing this?
Sending the data from AS3:
// compress xml using zlib
var xml:XML = <contents><thing>value</thing></contents>;
var bytes:ByteArray = new ByteArray();
bytes.writeObject(xml);
bytes.position = 0;
bytes.compress();
var request:URLRequest = new URLRequest(url);
var urlVariables :URLVariables = new URLVariables();
urlVariables.filename = "somefile.bin";
urlVariables.contents = bytes;
request.data = urlVariables;
request.method = URLRequestMethod.POST;
loader = new URLLoader();
loader.load(request);
Receiving it in the Java servlet and creating the file:
public void doPost(HttpServletRequest req, HttpServletResponse resp) throws IOException {
String filename = req.getParameter("filename");
byte[] contents = req.getParameter("contents").getBytes();
GSFileOptionsBuilder optionsBuilder = new GSFileOptionsBuilder()
.setBucket("bucketname")
.setKey(filename)
.setAcl("public-read")
.setMimeType("binary/octet-stream");
AppEngineFile writableFile = fileService.createNewGSFile(optionsBuilder.build());
boolean lockForWrite = true;
FileWriteChannel writeChannel = fileService.openWriteChannel(writableFile, lockForWrite);
writeChannel.write(ByteBuffer.wrap(contents));
writeChannel.closeFinally();
}
Opening the new file in AS3:
var url :String = "http://commondatastorage.googleapis.com/bucketname/somefile.bin";
var request:URLRequest = new URLRequest(url);
request.method = URLRequestMethod.GET;
loader = new URLLoader();
loader.addEventListener(Event.COMPLETE, handleComplete);
loader.load(request);
protected function handleComplete (event:Event):void {
var bytes:ByteArray = new ByteArray();
bytes.writeObject(event.target.data);
// dies on this line with "There was an error decompressing the data."
bytes.uncompress();
var xml:XML = new XML(new String(bytes));
trace(xml);
}

Here is the code that I use to save an xml. I send the data to PHP but I would think it would work the same way for you... I haven't had any trouble with it.
var createXMLURL:URLRequest = new URLRequest("createXML.php");
createXMLURL.method = URLRequestMethod.POST;
var Variables:URLVariables = new URLVariables();
Variables.xmlString = xml.toXMLString();
Variables.filename = filename;
createXMLURL.data = Variables;
var loader:URLLoader = new URLLoader();
loader.dataFormat = "VARIABLES";
loader.addEventListener(Event.COMPLETE, xmlCreated);
loader.load(createXMLURL);
Let me know if you have any questions about what some of the variables are since I did not include their declarations (I think they are pretty easy to figure out).
Now this doesn't send that data in binary format like you were asking for, but I don't know why you wouldn't be able to convert the string to binary once you receive it in java if you really need the raw bytes.

I would base64 encode before you POST if from the client, store it that way in a TextProerty, then base64 decode / decompress when received back at the client. If you want to store it as binary on GAE, then base64 decode it into a Blob. Here are some code snippets I pieced together using your code, and something similar I do using HttpService -- apologies in advance for not extensively proofing it. HTH.
private var _serviceHttp:HTTPService = new HTTPService;
private function postBytes():void {
var xml:XML = <contents><thing>value</thing></contents>;
var bytes:ByteArray = new ByteArray();
bytes.writeObject(xml);
bytes.position = 0;
bytes.compress();
var enc:Base64Encoder = new Base64Encoder();
enc.encodeBytes(bytes, 0, bytes.length);
var myObj:Object = new Object();
myObj["bytes"] = enc.toString();
// myObj["other_variables"] = your_other_varaibles;
_serviceHttp.method = "POST";
_serviceHttp.resultFormat = "flashvars";
_serviceHttp.url = your_url_here;
_serviceHttp.addEventListener(ResultEvent.RESULT, urlHandler);
_serviceHttp.addEventListener(FaultEvent.FAULT, urlErrorHandler);
_serviceHttp.send(myObj);
}