标签：
/*
* Copyright 2014 Google Inc. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.android.grafika;
import android.graphics.SurfaceTexture;
import android.hardware.Camera;
import android.opengl.GLES20;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
import android.app.Activity;
import com.android.grafika.gles.EglCore;
import com.android.grafika.gles.FullFrameRect;
import com.android.grafika.gles.Texture2dProgram;
import com.android.grafika.gles.WindowSurface;
import java.io.File;
import java.io.IOException;
import java.lang.ref.WeakReference;
/**
* Demonstrates capturing video into a ring buffer. When the "capture" button is clicked,
* the buffered video is saved.
* <p>
* Capturing and storing raw frames would be slow and require lots of memory. Instead, we
* feed the frames into the video encoder and buffer the output.
* <p>
* Whenever we receive a new frame from the camera, our SurfaceTexture callback gets
* notified. That can happen on an arbitrary thread, so we use it to send a message
* through our Handler. That causes us to render the new frame to the display and to
* our video encoder.
*/
public class ContinuousCaptureActivity extends Activity implements SurfaceHolder.Callback,
SurfaceTexture.OnFrameAvailableListener {
private static final String TAG = MainActivity.TAG;
private static final int VIDEO_WIDTH = 1280; // dimensions for 720p video
private static final int VIDEO_HEIGHT = 720;
private static final int DESIRED_PREVIEW_FPS = 15;
private EglCore mEglCore;
private WindowSurface mDisplaySurface;
private SurfaceTexture mCameraTexture; // receives the output from the camera preview
private FullFrameRect mFullFrameBlit;
private final float[] mTmpMatrix = new float[16];
private int mTextureId;
private int mFrameNum;
private Camera mCamera;
private int mCameraPreviewThousandFps;
private File mOutputFile;
private CircularEncoder mCircEncoder;
private WindowSurface mEncoderSurface;
private boolean mFileSaveInProgress;
private MainHandler mHandler;
private float mSecondsOfVideo;
/**
* Custom message handler for main UI thread.
* <p>
* Used to handle camera preview "frame available" notifications, and implement the
* blinking "recording" text. Receives callback messages from the encoder thread.
*/
private static class MainHandler extends Handler implements CircularEncoder.Callback {
public static final int MSG_BLINK_TEXT = 0;
public static final int MSG_FRAME_AVAILABLE = 1;
public static final int MSG_FILE_SAVE_COMPLETE = 2;
public static final int MSG_BUFFER_STATUS = 3;
private WeakReference<ContinuousCaptureActivity> mWeakActivity;
public MainHandler(ContinuousCaptureActivity activity) {
mWeakActivity = new WeakReference<ContinuousCaptureActivity>(activity);
}
// CircularEncoder.Callback, called on encoder thread
@Override
public void fileSaveComplete(int status) {
sendMessage(obtainMessage(MSG_FILE_SAVE_COMPLETE, status, 0, null));
}
// CircularEncoder.Callback, called on encoder thread
@Override
public void bufferStatus(long totalTimeMsec) {
sendMessage(obtainMessage(MSG_BUFFER_STATUS,
(int) (totalTimeMsec >> 32), (int) totalTimeMsec));
}
@Override
public void handleMessage(Message msg) {
ContinuousCaptureActivity activity = mWeakActivity.get();
if (activity == null) {
Log.d(TAG, "Got message for dead activity");
return;
}
switch (msg.what) {
case MSG_BLINK_TEXT: {
TextView tv = (TextView) activity.findViewById(R.id.recording_text);
// Attempting to make it blink by using setEnabled() doesn‘t work --
// it just changes the color. We want to change the visibility.
int visibility = tv.getVisibility();
if (visibility == View.VISIBLE) {
visibility = View.INVISIBLE;
} else {
visibility = View.VISIBLE;
}
tv.setVisibility(visibility);
int delay = (visibility == View.VISIBLE) ? 1000 : 200;
sendEmptyMessageDelayed(MSG_BLINK_TEXT, delay);
break;
}
case MSG_FRAME_AVAILABLE: {
activity.drawFrame();
break;
}
case MSG_FILE_SAVE_COMPLETE: {
activity.fileSaveComplete(msg.arg1);
break;
}
case MSG_BUFFER_STATUS: {
long duration = (((long) msg.arg1) << 32) |
(((long) msg.arg2) & 0xffffffffL);
activity.updateBufferStatus(duration);
break;
}
default:
throw new RuntimeException("Unknown message " + msg.what);
}
}
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_continuous_capture);
SurfaceView sv = (SurfaceView) findViewById(R.id.continuousCapture_surfaceView);
SurfaceHolder sh = sv.getHolder();
sh.addCallback(this);
mHandler = new MainHandler(this);
mHandler.sendEmptyMessageDelayed(MainHandler.MSG_BLINK_TEXT, 1500);
mOutputFile = new File(getFilesDir(), "continuous-capture.mp4");
mSecondsOfVideo = 0.0f;
updateControls();
}
@Override
protected void onResume() {
super.onResume();
// Ideally, the frames from the camera are at the same resolution as the input to
// the video encoder so we don‘t have to scale.
openCamera(VIDEO_WIDTH, VIDEO_HEIGHT, DESIRED_PREVIEW_FPS);
}
@Override
protected void onPause() {
super.onPause();
releaseCamera();
if (mCircEncoder != null) {
mCircEncoder.shutdown();
mCircEncoder = null;
}
if (mCameraTexture != null) {
mCameraTexture.release();
mCameraTexture = null;
}
if (mDisplaySurface != null) {
mDisplaySurface.release();
mDisplaySurface = null;
}
if (mFullFrameBlit != null) {
mFullFrameBlit.release(false);
mFullFrameBlit = null;
}
if (mEglCore != null) {
mEglCore.release();
mEglCore = null;
}
Log.d(TAG, "onPause() done");
}
/**
* Opens a camera, and attempts to establish preview mode at the specified width and height.
* <p>
* Sets mCameraPreviewFps to the expected frame rate (which might actually be variable).
*/
private void openCamera(int desiredWidth, int desiredHeight, int desiredFps) {
if (mCamera != null) {
throw new RuntimeException("camera already initialized");
}
Camera.CameraInfo info = new Camera.CameraInfo();
// Try to find a front-facing camera (e.g. for videoconferencing).
int numCameras = Camera.getNumberOfCameras();
for (int i = 0; i < numCameras; i++) {
Camera.getCameraInfo(i, info);
if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
mCamera = Camera.open(i);
break;
}
}
if (mCamera == null) {
Log.d(TAG, "No front-facing camera found; opening default");
mCamera = Camera.open(); // opens first back-facing camera
}
if (mCamera == null) {
throw new RuntimeException("Unable to open camera");
}
Camera.Parameters parms = mCamera.getParameters();
CameraUtils.choosePreviewSize(parms, desiredWidth, desiredHeight);
// Try to set the frame rate to a constant value.
mCameraPreviewThousandFps = CameraUtils.chooseFixedPreviewFps(parms, desiredFps * 1000);
// Give the camera a hint that we‘re recording video. This can have a big
// impact on frame rate.
parms.setRecordingHint(true);
mCamera.setParameters(parms);
Camera.Size cameraPreviewSize = parms.getPreviewSize();
String previewFacts = cameraPreviewSize.width + "x" + cameraPreviewSize.height +
" @" + (mCameraPreviewThousandFps / 1000.0f) + "fps";
Log.i(TAG, "Camera config: " + previewFacts);
// Set the preview aspect ratio.
AspectFrameLayout layout = (AspectFrameLayout) findViewById(R.id.continuousCapture_afl);
layout.setAspectRatio((double) cameraPreviewSize.width / cameraPreviewSize.height);
}
/**
* Stops camera preview, and releases the camera to the system.
*/
private void releaseCamera() {
if (mCamera != null) {
mCamera.stopPreview();
mCamera.release();
mCamera = null;
Log.d(TAG, "releaseCamera -- done");
}
}
/**
* Updates the current state of the controls.
*/
private void updateControls() {
String str = getString(R.string.secondsOfVideo, mSecondsOfVideo);
TextView tv = (TextView) findViewById(R.id.capturedVideoDesc_text);
tv.setText(str);
boolean wantEnabled = (mCircEncoder != null) && !mFileSaveInProgress;
Button button = (Button) findViewById(R.id.capture_button);
if (button.isEnabled() != wantEnabled) {
Log.d(TAG, "setting enabled = " + wantEnabled);
button.setEnabled(wantEnabled);
}
}
/**
* Handles onClick for "capture" button.
*/
public void clickCapture(@SuppressWarnings("unused") View unused) {
Log.d(TAG, "capture");
if (mFileSaveInProgress) {
Log.w(TAG, "HEY: file save is already in progress");
return;
}
// The button is disabled in onCreate(), and not enabled until the encoder and output
// surface is ready, so it shouldn‘t be possible to get here with a null mCircEncoder.
mFileSaveInProgress = true;
updateControls();
TextView tv = (TextView) findViewById(R.id.recording_text);
String str = getString(R.string.nowSaving);
tv.setText(str);
mCircEncoder.saveVideo(mOutputFile);
}
/**
* The file save has completed. We can resume recording.
*/
private void fileSaveComplete(int status) {
Log.d(TAG, "fileSaveComplete " + status);
if (!mFileSaveInProgress) {
throw new RuntimeException("WEIRD: got fileSaveCmplete when not in progress");
}
mFileSaveInProgress = false;
updateControls();
TextView tv = (TextView) findViewById(R.id.recording_text);
String str = getString(R.string.nowRecording);
tv.setText(str);
if (status == 0) {
str = getString(R.string.recordingSucceeded);
} else {
str = getString(R.string.recordingFailed, status);
}
Toast toast = Toast.makeText(this, str, Toast.LENGTH_SHORT);
toast.show();
}
/**
* Updates the buffer status UI.
*/
private void updateBufferStatus(long durationUsec) {
mSecondsOfVideo = durationUsec / 1000000.0f;
updateControls();
}
@Override // SurfaceHolder.Callback
public void surfaceCreated(SurfaceHolder holder) {
Log.d(TAG, "surfaceCreated holder=" + holder);
// Set up everything that requires an EGL context.
//
// We had to wait until we had a surface because you can‘t make an EGL context current
// without one, and creating a temporary 1x1 pbuffer is a waste of time.
//
// The display surface that we use for the SurfaceView, and the encoder surface we
// use for video, use the same EGL context.
mEglCore = new EglCore(null, EglCore.FLAG_RECORDABLE);
mDisplaySurface = new WindowSurface(mEglCore, holder.getSurface(), false);
mDisplaySurface.makeCurrent();
mFullFrameBlit = new FullFrameRect(
new Texture2dProgram(Texture2dProgram.ProgramType.TEXTURE_EXT));
mTextureId = mFullFrameBlit.createTextureObject();
mCameraTexture = new SurfaceTexture(mTextureId);
mCameraTexture.setOnFrameAvailableListener(this);
Log.d(TAG, "starting camera preview");
try {
mCamera.setPreviewTexture(mCameraTexture);
} catch (IOException ioe) {
throw new RuntimeException(ioe);
}
mCamera.startPreview();
// TODO: adjust bit rate based on frame rate?
// TODO: adjust video width/height based on what we‘re getting from the camera preview?
// (can we guarantee that camera preview size is compatible with AVC video encoder?)
try {
mCircEncoder = new CircularEncoder(VIDEO_WIDTH, VIDEO_HEIGHT, 6000000,
mCameraPreviewThousandFps / 1000, 7, mHandler);
} catch (IOException ioe) {
throw new RuntimeException(ioe);
}
mEncoderSurface = new WindowSurface(mEglCore, mCircEncoder.getInputSurface(), true);
updateControls();
}
@Override // SurfaceHolder.Callback
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
Log.d(TAG, "surfaceChanged fmt=" + format + " size=" + width + "x" + height +
" holder=" + holder);
}
@Override // SurfaceHolder.Callback
public void surfaceDestroyed(SurfaceHolder holder) {
Log.d(TAG, "surfaceDestroyed holder=" + holder);
}
@Override // SurfaceTexture.OnFrameAvailableListener; runs on arbitrary thread
public void onFrameAvailable(SurfaceTexture surfaceTexture) {
//Log.d(TAG, "frame available");
mHandler.sendEmptyMessage(MainHandler.MSG_FRAME_AVAILABLE);
}
/**
* Draws a frame onto the SurfaceView and the encoder surface.
* <p>
* This will be called whenever we get a new preview frame from the camera. This runs
* on the UI thread, which ordinarily isn‘t a great idea -- you really want heavy work
* to be on a different thread -- but we‘re really just throwing a few things at the GPU.
* The upside is that we don‘t have to worry about managing state changes between threads.
* <p>
* If there was a pending frame available notification when we shut down, we might get
* here after onPause().
*/
private void drawFrame() {
//Log.d(TAG, "drawFrame");
if (mEglCore == null) {
Log.d(TAG, "Skipping drawFrame after shutdown");
return;
}
// Latch the next frame from the camera.
mDisplaySurface.makeCurrent();
mCameraTexture.updateTexImage();
mCameraTexture.getTransformMatrix(mTmpMatrix);
// Fill the SurfaceView with it.
SurfaceView sv = (SurfaceView) findViewById(R.id.continuousCapture_surfaceView);
int viewWidth = sv.getWidth();
int viewHeight = sv.getHeight();
GLES20.glViewport(0, 0, viewWidth, viewHeight);
mFullFrameBlit.drawFrame(mTextureId, mTmpMatrix);
drawExtra(mFrameNum, viewWidth, viewHeight);
mDisplaySurface.swapBuffers();
// Send it to the video encoder.
if (!mFileSaveInProgress) {
mEncoderSurface.makeCurrent();
GLES20.glViewport(0, 0, VIDEO_WIDTH, VIDEO_HEIGHT);
mFullFrameBlit.drawFrame(mTextureId, mTmpMatrix);
drawExtra(mFrameNum, VIDEO_WIDTH, VIDEO_HEIGHT);
mCircEncoder.frameAvailableSoon();
mEncoderSurface.setPresentationTime(mCameraTexture.getTimestamp());
mEncoderSurface.swapBuffers();
}
mFrameNum++;
}
/**
* Adds a bit of extra stuff to the display just to give it flavor.
*/
private static void drawExtra(int frameNum, int width, int height) {
// We "draw" with the scissor rect and clear calls. Note this uses window coordinates.
int val = frameNum % 3;
switch (val) {
case 0: GLES20.glClearColor(1.0f, 0.0f, 0.0f, 1.0f); break;
case 1: GLES20.glClearColor(0.0f, 1.0f, 0.0f, 1.0f); break;
case 2: GLES20.glClearColor(0.0f, 0.0f, 1.0f, 1.0f); break;
}
int xpos = (int) (width * ((frameNum % 100) / 100.0f));
GLES20.glEnable(GLES20.GL_SCISSOR_TEST);
GLES20.glScissor(xpos, 0, width / 32, height / 32);
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
GLES20.glDisable(GLES20.GL_SCISSOR_TEST);
}
}
标签：
原文地址：http://www.cnblogs.com/jymblog/p/5521931.html
