Cách chuyển đổi Bitmap thành Base64 String

Question

Tôi đang phát triển một ứng dụng Android tải lên Base64 Chuỗi hình ảnh vào máy chủ web. Vì vậy, tôi đã sử dụng đoạn mã sau để chuyển đổi một Bitmap thành Base64 Chuỗi.

public String getEncoded64ImageStringFromBitmap(Bitmap bitmap) { 
    ByteArrayOutputStream stream = new ByteArrayOutputStream(); 
    bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream); 
    byte[] byteFormat = stream.toByteArray(); 
    String imgString = Base64.encodeToString(byteFormat, Base64.NO_WRAP); 
    return imgString; 
} 

Ví dụ: tôi cần chuyển đổi số image này. Sau khi chuyển đổi, tôi không nhận được chuỗi Base64 như tôi mong đợi.

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 

Các thực Base64 Chuỗi nó phải được điều này (tôi sử dụng này website để chuyển đổi)

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 

vấn đề trong chuyển đổi của tôi là gì? Cảm ơn bạn!

Answer 1

sử dụng đoạn mã sau đây để chuyển đổi bitmap để mảng byte:

ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream(); 
bitmap.compress(Bitmap.CompressFormat.PNG, 100, byteArrayOutputStream); 
byte[] byteArray = byteArrayOutputStream .toByteArray(); 

sau đó để mã hóa base64 từ mảng byte sử dụng câu lệnh sau:

String encoded = Base64.encodeToString(byteArray, Base64.DEFAULT); 

Answer 2

public static String encodeTobase64(Bitmap image) 
{ 
    Bitmap immagex=image; 
    ByteArrayOutputStream baos = new ByteArrayOutputStream(); 
    immagex.compress(Bitmap.CompressFormat.PNG, 100, baos); 
    byte[] b = baos.toByteArray(); 
    String imageEncoded = Base64.encodeToString(b,Base64.DEFAULT); 
    return imageEncoded; 
} 

public static Bitmap decodeBase64(String input) 
{ 
    byte[] decodedByte = Base64.decode(input, 0); 
    return BitmapFactory.decodeByteArray(decodedByte, 0, decodedByte.length); 
} 

Answer 3

public String getBase64ImageString(Bitmap photo) { 
     String imgString; 
     if(photo != null) { 
      ByteArrayOutputStream outputStream = new ByteArrayOutputStream(); 
      photo.compress(Bitmap.CompressFormat.PNG, 100, outputStream); 
      byte[] profileImage = outputStream.toByteArray(); 

      imgString = Base64.encodeToString(profileImage, 
        Base64.NO_WRAP); 
     }else{ 
      imgString = ""; 
     } 

     return imgString; 
    } 

Vượt qua Bitmap của bạn trong các tham số bạn sẽ nhận được chuỗi hình ảnh của mình.