我有一个基于grafika's examples的直播应用,我通过RTMP发送视频直播进行直播。
我现在想通过在视频流上叠加文字或徽标来为我的视频添加水印。我知道这可以通过GLSL过滤来完成,但我不知道如何根据我链接的样本来实现它。
我尝试使用Alpha混合,但似乎两种纹理格式在某种程度上不兼容(一种是TEXTURE_EXTERNAL_OES,另一种是TEXTURE_2D),我只是得到了一个黑框。
编辑:
我的代码基于Kickflip API:
class CameraSurfaceRenderer implements GLSurfaceView.Renderer {
private static final String TAG = "CameraSurfaceRenderer";
private static final boolean VERBOSE = false;
private CameraEncoder mCameraEncoder;
private FullFrameRect mFullScreenCamera;
private FullFrameRect mFullScreenOverlay; // For texture overlay
private final float[] mSTMatrix = new float[16];
private int mOverlayTextureId;
private int mCameraTextureId;
private boolean mRecordingEnabled;
private int mFrameCount;
// Keep track of selected filters + relevant state
private boolean mIncomingSizeUpdated;
private int mIncomingWidth;
private int mIncomingHeight;
private int mCurrentFilter;
private int mNewFilter;
boolean showBox = false;
/**
* Constructs CameraSurfaceRenderer.
* <p>
* @param recorder video encoder object
*/
public CameraSurfaceRenderer(CameraEncoder recorder) {
mCameraEncoder = recorder;
mCameraTextureId = -1;
mFrameCount = -1;
SessionConfig config = recorder.getConfig();
mIncomingWidth = config.getVideoWidth();
mIncomingHeight = config.getVideoHeight();
mIncomingSizeUpdated = true; // Force texture size update on next onDrawFrame
mCurrentFilter = -1;
mNewFilter = Filters.FILTER_NONE;
mRecordingEnabled = false;
}
/**
* Notifies the renderer that we want to stop or start recording.
*/
public void changeRecordingState(boolean isRecording) {
Log.d(TAG, "changeRecordingState: was " + mRecordingEnabled + " now " + isRecording);
mRecordingEnabled = isRecording;
}
@Override
public void onSurfaceCreated(GL10 unused, EGLConfig config) {
Log.d(TAG, "onSurfaceCreated");
// Set up the texture blitter that will be used for on-screen display. This
// is *not* applied to the recording, because that uses a separate shader.
mFullScreenCamera = new FullFrameRect(
new Texture2dProgram(Texture2dProgram.ProgramType.TEXTURE_EXT));
// For texture overlay:
GLES20.glEnable(GLES20.GL_BLEND);
GLES20.glBlendFunc(GLES20.GL_SRC_ALPHA, GLES20.GL_ONE_MINUS_SRC_ALPHA);
mFullScreenOverlay = new FullFrameRect(
new Texture2dProgram(Texture2dProgram.ProgramType.TEXTURE_2D));
mOverlayTextureId = GlUtil.createTextureWithTextContent("hello!");
mOverlayTextureId = GlUtil.createTextureFromImage(mCameraView.getContext(), R.drawable.red_dot);
mCameraTextureId = mFullScreenCamera.createTextureObject();
mCameraEncoder.onSurfaceCreated(mCameraTextureId);
mFrameCount = 0;
}
@Override
public void onSurfaceChanged(GL10 unused, int width, int height) {
Log.d(TAG, "onSurfaceChanged " + width + "x" + height);
}
@Override
public void onDrawFrame(GL10 unused) {
if (VERBOSE){
if(mFrameCount % 30 == 0){
Log.d(TAG, "onDrawFrame tex=" + mCameraTextureId);
mCameraEncoder.logSavedEglState();
}
}
if (mCurrentFilter != mNewFilter) {
Filters.updateFilter(mFullScreenCamera, mNewFilter);
mCurrentFilter = mNewFilter;
mIncomingSizeUpdated = true;
}
if (mIncomingSizeUpdated) {
mFullScreenCamera.getProgram().setTexSize(mIncomingWidth, mIncomingHeight);
mFullScreenOverlay.getProgram().setTexSize(mIncomingWidth, mIncomingHeight);
mIncomingSizeUpdated = false;
Log.i(TAG, "setTexSize on display Texture");
}
// Draw the video frame.
if(mCameraEncoder.isSurfaceTextureReadyForDisplay()){
mCameraEncoder.getSurfaceTextureForDisplay().updateTexImage();
mCameraEncoder.getSurfaceTextureForDisplay().getTransformMatrix(mSTMatrix);
//Drawing texture overlay:
mFullScreenOverlay.drawFrame(mOverlayTextureId, mSTMatrix);
mFullScreenCamera.drawFrame(mCameraTextureId, mSTMatrix);
}
mFrameCount++;
}
public void signalVertialVideo(FullFrameRect.SCREEN_ROTATION isVertical) {
if (mFullScreenCamera != null) mFullScreenCamera.adjustForVerticalVideo(isVertical, false);
}
/**
* Changes the filter that we're applying to the camera preview.
*/
public void changeFilterMode(int filter) {
mNewFilter = filter;
}
public void handleTouchEvent(MotionEvent ev){
mFullScreenCamera.handleTouchEvent(ev);
}
}
这是在屏幕上渲染图像的代码(GLSurfaceView),但实际上并没有覆盖在视频上。如果我没有记错的话,可以在CameraEncoder上完成。
事实是,将CameraSurfaceRenderer中的代码复制到CameraEncoder中(它们在过滤器时都有类似的代码)不提供重叠的文本/图像。
答案 0 :(得分:0)
纹理对象使用GL_TEXTURE_EXTERNAL_OES纹理目标,该目标由GL_OES_EGL_image_external OpenGL ES扩展定义。这限制了纹理的使用方式。每次绑定纹理时,它必须绑定到GL_TEXTURE_EXTERNAL_OES目标而不是GL_TEXTURE_2D目标。此外,任何从纹理中采样的OpenGL ES 2.0着色器必须使用例如“#extension GL_OES_EGL_image_external:require”指令声明其对此扩展的使用。此类着色器还必须使用samplerExternalOES GLSL采样器类型访问纹理。
https://developer.android.com/reference/android/graphics/SurfaceTexture.html
发布您用于进行Alpha混合的代码,我可以修复它。
我可能会覆盖Texture2dProgram并将其传递给FullFrame渲染器。它具有使用GL_TEXTURE_EXTERNAL_OES
扩展名进行渲染的示例代码。基本上,@ Overver draw
函数,调用基本实现,绑定水印并绘制。
应该在相机和视频编码器之间。