Question

我尝试在chplay中编写像ipcam app这样的应用程序（使用我的智能手机就像无线网络摄像头），我使用相机API捕获1张图片并将其发送到网站确定。

但现在，我想拍摄照片并不断将它们发送到我的网站。通常情况下，我使用一个按钮来捕获图像，使用一个按钮上传图像，但是当我不使用按钮时，它将无法运行。

如何解决此问题并将图片连续流式传输到我的网站？

这是我的所有代码：

public class MainActivity extends AppCompatActivity {
    private Camera camera;
    private LinearLayout scrollImages;
    Button btnCapture, btnSave, btnUpload, btnExit;
    SurfaceView surfaceView;
    SurfaceHolder holder;
    Bitmap bitmap, scaledBitmap, rotatedBitmap;
    String path, MyImage_Encode;
    byte[] MyImage;
    boolean tt = false;
    ImageView imageView;
    InputStream inputStream;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        scrollImages = (LinearLayout)findViewById(R.id.scrollImages);
        btnCapture = (Button) findViewById(R.id.btnCapture);
        btnSave = (Button) findViewById(R.id.btnSave);
        btnUpload = (Button) findViewById(R.id.btnUpload);
        btnExit = (Button) findViewById(R.id.btnExit);
        surfaceView = (SurfaceView) findViewById(R.id.surfaceView);
        holder = surfaceView.getHolder();

        holder.addCallback(new SurfaceHolder.Callback() {

            @Override
            public void surfaceCreated(SurfaceHolder holder) {
                camera = camera.open();
            }

            @Override
            public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {

                try {
                    camera.setPreviewDisplay(holder);
                    camera.startPreview();
                    camera.setDisplayOrientation(90);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }

            @Override
            public void surfaceDestroyed(SurfaceHolder holder) {
                camera.stopPreview();
                camera.release();
                camera = null;
            }
        });

        btnCapture.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                camera.takePicture(null, null, new Camera.PictureCallback() {
                    @Override
                    public void onPictureTaken(byte[] data, Camera camera) {
                        BitmapFactory.Options options = new BitmapFactory.Options();
                        options.inSampleSize = 4;
                        bitmap = BitmapFactory.decodeByteArray(data, 0, data.length, options);

                        Matrix matrix = new Matrix();
                        matrix.postRotate(90);
                        scaledBitmap = Bitmap.createScaledBitmap(bitmap, bitmap.getWidth(), bitmap.getHeight(), true);
                        rotatedBitmap = Bitmap.createBitmap(scaledBitmap, 0, 0, scaledBitmap.getWidth(), scaledBitmap.getHeight(), matrix, true);

                        imageView = new ImageView(getApplicationContext());
                        imageView.setImageBitmap(rotatedBitmap);

                        ByteArrayOutputStream bao = new ByteArrayOutputStream();
                        rotatedBitmap.compress(Bitmap.CompressFormat.JPEG, 100, bao);
                        MyImage = bao.toByteArray();
                    }
                });
            }
        });

        btnSave.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                File file = new File(Environment.getExternalStorageDirectory()+File.separator + "image.jpg");
                try {
                    FileOutputStream fos = new FileOutputStream(file);
                    fos.write(MyImage);
                    fos.close();
                    Toast.makeText(MainActivity.this, "New Image saved", Toast.LENGTH_LONG).show();
                } catch (Exception error) {
                    Toast.makeText(MainActivity.this, "Image could not be saved.", Toast.LENGTH_LONG).show();
                }
            }
        });

        btnUpload.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                MyImage_Encode = Base64.encodeToString(MyImage, Base64.DEFAULT);
                final ArrayList<NameValuePair> nameValuePairs = new  ArrayList<NameValuePair>();
                nameValuePairs.add(new BasicNameValuePair("image",MyImage_Encode));
                Thread t = new Thread(new Runnable() {

                    @Override
                    public void run() {
                        try{
                            HttpClient httpclient = new DefaultHttpClient();
                            HttpPost httppost = new HttpPost("http://nns12151069.esy.es/upload_image.php");
                            httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
                            HttpResponse response = httpclient.execute(httppost);
                            runOnUiThread(new Runnable() {

                                @Override
                                public void run() {
                                    Toast.makeText(MainActivity.this, "Image Upload Successful", Toast.LENGTH_LONG).show();
                                }
                            });
                        } catch(Exception e) {
                            runOnUiThread(new Runnable() {
                                @Override
                                public void run() {
                                    Toast.makeText(MainActivity.this, "Image Upload Failed", Toast.LENGTH_LONG).show();
                                }
                            });
                        }
                    }
                });
                t.start();
            }
        });

        LinearLayout layoutBackground = (LinearLayout) findViewById(R.id.background);
        layoutBackground.setOnClickListener(new LinearLayout.OnClickListener() {

            @Override
            public void onClick(View v) {
                camera.autoFocus(myAutoFocusCallback);
            }

            Camera.AutoFocusCallback myAutoFocusCallback = new Camera.AutoFocusCallback() {
                @Override
                public void onAutoFocus(boolean success, Camera camera) {
                }
            };
        });
    }
}

Answer 1

拍摄照片时，相机预览会自动停止。如果您没有运行相机预览，则无法拍照。

因此，您应该在每次takePicture操作后重新开始预览。

Answer 2

我建议只发送预览帧。看看PreviewCallback

http://developer.android.com/reference/android/hardware/Camera.PreviewCallback.html

如何在Android相机API中连续捕获图像

2 个答案: