拍照并将其上传到服务器，无需任何压缩 android

Question

我正在尝试从设备相机拍摄照片或从图库中获取照片并通过 volley 将其上传到服务器 一切正常，但图像质量太差了

private void dispatchTakePictureIntent()
{
    Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    startActivityForResult(intent , CAMERA_REQUEST_CODE);
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data { 
    switch (requestCode) {
    case CAMERA_REQUEST_CODE:
    if ( resultCode == RESULT_OK){                 
    Bundle bundle = data.getExtras();
    bitmap = (Bitmap) bundle.get("data");
    ByteArrayOutputStream stream = new ByteArrayOutputStream();
    bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream);                    
}
break;

和 getParams 方法：

    byte[] a = convertBitmapToByteArrayUncompressed(bitmap);
    params.put("img" , Base64.encodeToString(a , Base64.DEFAULT));

public static byte[] convertBitmapToByteArrayUncompressed(Bitmap bitmap){
    ByteBuffer byteBuffer = ByteBuffer.allocate(bitmap.getByteCount());
    bitmap.copyPixelsToBuffer(byteBuffer);
    byteBuffer.rewind();
    return byteBuffer.array();
}

Answer 1

从 Naugat 拍照会有所不同。

创建一个图像文件拳头：

String mCurrentPhotoPath;

private File createImageFile() throws IOException {
    // Create an image file name
    String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
    String imageFileName = "JPEG_" + timeStamp + "_";
    File storageDir = getExternalFilesDir(Environment.DIRECTORY_PICTURES);
    File image = File.createTempFile(
        imageFileName,  /* prefix */
        ".jpg",         /* suffix */
        storageDir      /* directory */
    );

    // Save a file: path for use with ACTION_VIEW intents
    mCurrentPhotoPath = image.getAbsolutePath();
    return image;
}

然后发送拍照意图

static final int REQUEST_TAKE_PHOTO = 1;

private void dispatchTakePictureIntent() {
    Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    // Ensure that there's a camera activity to handle the intent
    if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
        // Create the File where the photo should go
        File photoFile = null;
        try {
            photoFile = createImageFile();
        } catch (IOException ex) {
            // Error occurred while creating the File
            ...
        }
        // Continue only if the File was successfully created
        if (photoFile != null) {
            Uri photoURI = FileProvider.getUriForFile(this,
                                                  "com.example.android.fileprovider",
                                                  photoFile);
            takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoURI);
            startActivityForResult(takePictureIntent, REQUEST_TAKE_PHOTO);
        }
    }
}

在您的 onActivity 结果中检查 RESULT_OK 是否成功捕获。

if (requestCode == REQUEST_TAKE_PHOTO && resultCode == Activity.RESULT_OK)

您已经获得了图像路径。现在使用mCurrentPhotoPath进行上传。

另外，你需要实现文件提供者。

在您的清单中添加：

<application>
   ...
   <provider
        android:name="android.support.v4.content.FileProvider"
        android:authorities="com.example.android.fileprovider"
        android:exported="false"
        android:grantUriPermissions="true">
        <meta-data
            android:name="android.support.FILE_PROVIDER_PATHS"
            android:resource="@xml/file_paths"></meta-data>
    </provider>
    ...
</application>

在资源目录中的 XML 中添加：

<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <external-path name="my_images" path="Android/data/com.example.package.name/files/Pictures" />
</paths>

现在您将获得来自相机的全尺寸图像。

来源：https://developer.android.com/training/camera/photobasics.html

Answer 2

您应该必须使用多部分实体来发送未经压缩的图像。使用多部分实体，您的图像质量也将保持不变。请按照此使用凌空发送图像

public class MultipartReq extends JsonObjectRequest {

    private static final String FILE_PART_NAME = "file";
    private static final String STRING_PART_NAME = "text";

    private final File mFilePart;
    //private final String mStringPart;


    MultipartEntityBuilder entityBuilder = MultipartEntityBuilder.create();
    HttpEntity httpEntity;
    Context context;

    private Map<String, String> params;
    public MultipartReq(Context context, int method, String url, JSONObject jsonRequest, Response.Listener<JSONObject> listener, Response.ErrorListener errorListener, File file, Map<String, String> params) {
        super(method, url, jsonRequest, listener, errorListener);

        this.context = context;
        mFilePart = file;
        entityBuilder.setMode(HttpMultipartMode.BROWSER_COMPATIBLE);    
        this.params = params;
        buildMultipartEntity();
        httpEntity = entityBuilder.build();

    }


    private void buildMultipartEntity() {

        try {
            if (mFilePart.exists()) {                                           entityBuilder.addBinaryBody(FILE_PART_NAME, mFilePart, ContentType.create(mimeType), mFilePart.getName());

                }
                try {
                    if(!params.isEmpty()){
                        for (String key: params.keySet()){
                             entityBuilder.addPart(key, new StringBody(params.get(key),ContentType.TEXT_PLAIN));

                        }
                    }
                } catch (Exception e) {
                    VolleyLog.e("UnsupportedEncodingException");
                }


            } else {
                ShowLog.e("no such file");
            }
        } catch (Exception e) {
            ShowLog.e("UnsupportedEncodingException");
        }
    }

    @Override
    public Map<String, String> getHeaders() throws AuthFailureError {
        HashMap<String, String> params = new HashMap<String, String>();

        return params;
    }


    @Override
    public String getBodyContentType() {
        return httpEntity.getContentType().getValue();
    }

    @Override
    public byte[] getBody() {
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        try {
            httpEntity.writeTo(bos);
        } catch (IOException e) {
            VolleyLog.e("IOException writing to ByteArrayOutputStream");
        }
        return bos.toByteArray();
    }


    @Override
    protected void deliverResponse(JSONObject response) {
        super.deliverResponse(response);
    }
}

Answer 3

使用getParcelableExtra()，而不是getExtras() 用于小尺寸图片。

Bitmap bitmap = (Bitmap) intent.getParcelableExtra("data");

如果您的图像太大，您必须压缩它们并发送到其他活动。然后你可以得到压缩的位图并在第二个活动中解压缩它。试试下面的代码。

第一次活动

Intent intent = new Intent(this, SecondActivity.class);
ByteArrayOutputStream stream = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.JPG, 100, stream);
byte[] bytes = stream.toByteArray(); 
intent.putExtra("bitmap",bytes);

第二次活动

byte[] bytes = getIntent().getByteArrayExtra("bitmap");
Bitmap bitmap = BitmapFactory.decodeByteArray(bytes, 0, bytes.length);