Implement AndroidTextureBuffer::NativeToI420.

talk/app/webrtc/java/android/org/webrtc/SurfaceTextureHelper.java

Index: talk/app/webrtc/java/android/org/webrtc/SurfaceTextureHelper.java
diff --git a/talk/app/webrtc/java/android/org/webrtc/SurfaceTextureHelper.java b/talk/app/webrtc/java/android/org/webrtc/SurfaceTextureHelper.java
index 2df7716446cb11bd5e2560feb87b9fe879ef038b..31833c598b3564bae4e22f06e78efc62a35399b0 100644
--- a/talk/app/webrtc/java/android/org/webrtc/SurfaceTextureHelper.java
+++ b/talk/app/webrtc/java/android/org/webrtc/SurfaceTextureHelper.java
@@ -35,6 +35,10 @@ import android.os.Handler;
 import android.os.HandlerThread;
 import android.os.SystemClock;
 
+import org.webrtc.Logging;
+
+import java.nio.ByteBuffer;
+import java.nio.FloatBuffer;
 import java.util.concurrent.Callable;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
@@ -94,11 +98,305 @@ class SurfaceTextureHelper {
     });
   }
 
+  // State for RGBA conversion, instantiated on demand.
+  static private class ConvertRGBA {

[magjed_webrtc, 2015/12/03 12:33:58]

I don't want to land a ConvertToRGBA until we need it, so you can remove it from
this CL.

[nisse-webrtc, 2015/12/03 13:35:20]

I'll do. I wonder if it's worth the effort to keep the code around in some local
branch, though.

[magjed_webrtc, 2015/12/03 14:30:46]

Yes, do that :) It is also saved in the patch history here.

+    private final EglBase eglBase;
+    private GlRectDrawer drawer;
+    ConvertRGBA (EGLContext sharedContext) {
+      eglBase = new EglBase(sharedContext, EglBase.CONFIG_PIXEL_BUFFER);
+      drawer = null;
+    }
+
+    public void convert(ByteBuffer buf,
+        int width, int height, int textureId, float [] transformMatrix) {
+      synchronized(this) {
+        int size = 4 * width * height;
+        if (buf.capacity() < size) {
+          Logging.e(TAG, "needed size: " + size + ", available size: " + buf.capacity());
+          throw new IllegalStateException("ConvertRGBA.convert called with too small buffer");
+        }
+        // Produce a frame buffer starting at top-left corner, not
+        // bottom-left.
+        transformMatrix =
+            RendererCommon.multiplyMatrices(transformMatrix,
+                RendererCommon.verticalFlipMatrix());
+
+        try {
+          // Reuse surface, if possible.
+          if (eglBase.hasSurface()) {
+            if (eglBase.surfaceWidth() != width ||
+                eglBase.surfaceHeight() != height){
+              eglBase.releaseSurface();
+              eglBase.createPbufferSurface(width, height);
+            }
+          } else {
+            eglBase.createPbufferSurface(width, height);
+          }
+
+          eglBase.makeCurrent();
+          GLES20.glViewport(0, 0, width, height);
+          GlUtil.checkNoGLES2Error("Viewport");
+
+          if (drawer == null)
+            drawer = new GlRectDrawer();
+
+          drawer.drawOes(textureId, transformMatrix);
+          GLES20.glReadPixels(0, 0, width, height, GLES20.GL_RGBA, GLES20.GL_UNSIGNED_BYTE, buf);
+          GlUtil.checkNoGLES2Error("glReadPixels");
+        }
+        finally {
+          eglBase.detachCurrent();
+        }
+      }
+    }
+    public void release() {
+      synchronized(this) {
+        eglBase.makeCurrent();
+        if (drawer != null)
+          drawer.release();
+        eglBase.release();
+      }
+    }
+  }
+
+  // State for YUV conversion, instantiated on demand.
+  static private class ConvertYUV {
+    private final EglBase eglBase;
+    private final GlShader shader;
+    private boolean released = false;
+
+    // Vertex coordinates in Normalized Device Coordinates, i.e.
+    // (-1, -1) is bottom-left and (1, 1) is top-right.
+    private static final FloatBuffer DEVICE_RECTANGLE =
+        GlUtil.createFloatBuffer(new float[] {
+              -1.0f, -1.0f,  // Bottom left.
+               1.0f, -1.0f,  // Bottom right.
+              -1.0f,  1.0f,  // Top left.
+               1.0f,  1.0f,  // Top right.
+            });
+
+    // Texture coordinates - (0, 0) is bottom-left and (1, 1) is top-right.
+    private static final FloatBuffer TEXTURE_RECTANGLE =
+        GlUtil.createFloatBuffer(new float[] {
+              0.0f, 0.0f,  // Bottom left.
+              1.0f, 0.0f,  // Bottom right.
+              0.0f, 1.0f,  // Top left.
+              1.0f, 1.0f   // Top right.
+            });
+
+    private static final String VERTEX_SHADER =
+        "varying vec2 interp_tc;\n"
+      + "attribute vec4 in_pos;\n"
+      + "attribute vec4 in_tc;\n"
+      + "\n"
+      + "uniform mat4 texMatrix;\n"
+      + "\n"
+      + "void main() {\n"
+      + "    gl_Position = in_pos;\n"
+      + "    interp_tc = (texMatrix * in_tc).xy;\n"
+      + "}\n";
+
+    private static final String FRAGMENT_SHADER =
+        "#extension GL_OES_EGL_image_external : require\n"
+      + "precision mediump float;\n"
+      + "varying vec2 interp_tc;\n"
+      + "\n"
+      + "uniform samplerExternalOES oesTex;\n"
+      // Difference in texture coordinate corresponding to one
+      // sub-pixel in the x direction.
+      + "uniform vec2 xUnit;\n"
+      // Color conversion coefficients, including constant term
+      + "uniform vec4 coeffs;\n"
+      + "\n"
+      + "void main() {\n"
+      // TODO(nisse): Arrange color values into a matrix?
+      + "  gl_FragColor.r = coeffs.a + dot(coeffs.rgb,\n"
+      + "      texture2D(oesTex, interp_tc - 1.5 * xUnit).rgb);\n"

[magjed_webrtc, 2015/12/03 12:33:58]

The alpha value from the texture2D should always be 1, so just do a full dot,
i.e. dot(coeffs, texture2D(oesTex, interp_tc).
You can also experiment with:
gl_FragColor = 
    mat4(texture2D(oesTex, interp_tc - 1.5 * xUnit),
         texture2D(oesTex, interp_tc - 0.5 * xUnit),
         texture2D(oesTex, interp_tc + 0.5 * xUnit),
         texture2D(oesTex, interp_tc + 1.5 * xUnit))
    * coeffs;

+      + "  gl_FragColor.g = coeffs.a + dot(coeffs.rgb,\n"
+      + "      texture2D(oesTex, interp_tc - 0.5 * xUnit).rgb);\n"
+      + "  gl_FragColor.b = coeffs.a + dot(coeffs.rgb,\n"
+      + "      texture2D(oesTex, interp_tc + 0.5 * xUnit).rgb);\n"
+      + "  gl_FragColor.a = coeffs.a + dot(coeffs.rgb,\n"
+      + "      texture2D(oesTex, interp_tc + 1.5 * xUnit).rgb);\n"
+      + "}\n";
+
+    private int texMatrixLoc;
+    private int xUnitLoc;
+    private int coeffsLoc;;
+
+    ConvertYUV (EGLContext sharedContext) {
+      eglBase = new EglBase(sharedContext, EglBase.CONFIG_PIXEL_RGBA_BUFFER);
+      eglBase.createDummyPbufferSurface();
+      eglBase.makeCurrent();
+      try {

[magjed_webrtc, 2015/12/03 12:33:58]

You don't need this try-finally. Detaching the EGLContext is not critical when a
RuntimeException is thrown.

[nisse-webrtc, 2015/12/04 09:40:34]

Done.

+        shader = new GlShader(VERTEX_SHADER, FRAGMENT_SHADER);
+        shader.useProgram();
+        texMatrixLoc = shader.getUniformLocation("texMatrix");
+        xUnitLoc = shader.getUniformLocation("xUnit");
+        coeffsLoc = shader.getUniformLocation("coeffs");
+        GLES20.glUniform1i(shader.getUniformLocation("oesTex"), 0);
+        GlUtil.checkNoGLES2Error("Initialize fragment shader uniform values.");
+        // Initialize vertex shader attributes.
+        shader.setVertexAttribArray("in_pos", 2, DEVICE_RECTANGLE);
+        // If the width is not a multiple of 4 pixels, the texture
+        // will be scaled up slightly and clipped at the right border.
+        shader.setVertexAttribArray("in_tc", 2, TEXTURE_RECTANGLE);
+      }
+      finally {
+        eglBase.detachCurrent();
+      }
+    }
+
+    public void convert(ByteBuffer buf,
+        int width, int height, int stride, int textureId, float [] transformMatrix) {

[magjed_webrtc, 2015/12/03 12:33:58]

why do you need a stride value? width/height should be enough?

[nisse-webrtc, 2015/12/03 13:35:20]

To allow for some additional alignment, and at the same time avoid duplicating
the code which selects the stride.

+      synchronized(this) {

[magjed_webrtc, 2015/12/03 12:33:58]

If the whole function is synchronized on |this|, you can just write public void
synchronized convert() instead.

[nisse-webrtc, 2015/12/03 13:35:20]

Acknowledged.

[nisse-webrtc, 2015/12/04 09:40:34]

Done.

+        // TODO(nisse): For now only produces the Y plane.
+        if (released) {
+          throw new IllegalStateException(
+              "ConvertYUV.convert called on released object");
+        }
+        if (stride % 8 != 0) {
+          throw new IllegalArgumentException(
+              "Invalid stride, must be a multiple of 8");

[magjed_webrtc, 2015/12/03 12:33:58]

why?

[nisse-webrtc, 2015/12/03 13:35:20]

Because we do a split in half for drawing u and v, and the v part must start at
an x coordinate which is a multiple of 4.

I ought to write a comment somewhere explaining the layout.

+        }
+        if (stride < width){
+          throw new IllegalArgumentException(
+              "Invalid stride, must >= width");
+        }
+
+        int y_width = (width+3) / 4;
+        int uv_width = (width+7) / 8;
+        int uv_height = (height+1)/2;
+        int total_height = height + uv_height;
+        int size = stride * total_height;
+
+        Logging.e(TAG, "width: " + width + ", height: " + height +
+            ", y-width: " + y_width + ", stride: " + stride);
+
+        Logging.e(TAG, "matrix: \n " + transformMatrix[0]
+            + " " + transformMatrix[1]
+            + " " + transformMatrix[2]
+            + " " + transformMatrix[3]
+            + "\n " + transformMatrix[4]
+            + " " + transformMatrix[5]
+            + " " + transformMatrix[6]
+            + " " + transformMatrix[7]
+            + "\n " + transformMatrix[8]
+            + " " + transformMatrix[9]
+            + " " + transformMatrix[10]
+            + " " + transformMatrix[11]
+            + "\n " + transformMatrix[12]
+            + " " + transformMatrix[13]
+            + " " + transformMatrix[14]
+            + " " + transformMatrix[15]);
+
+        if (buf.capacity() < size) {
+          Logging.e(TAG, "needed size: " + size + ", available size: " + buf.capacity());
+          throw new IllegalStateException("ConvertYUV.convert called with too small buffer");

[magjed_webrtc, 2015/12/03 12:33:58]

IllegalArgument

[nisse-webrtc, 2015/12/04 09:40:34]

Done.

+        }
+        // Produce a frame buffer starting at top-left corner, not
+        // bottom-left.
+        transformMatrix =
+            RendererCommon.multiplyMatrices(transformMatrix,
+                RendererCommon.verticalFlipMatrix());
+
+        try {
+          // Reuse surface, if possible. TODO(nisse): Add an eglBase
+          // helper function, say, makeCurrentWithSize.
+          if (eglBase.hasSurface()) {
+            if (eglBase.surfaceWidth() != stride/4 ||
+                eglBase.surfaceHeight() != total_height){
+              eglBase.releaseSurface();
+              eglBase.createPbufferSurface(stride/4, total_height);
+            }
+          } else {
+            eglBase.createPbufferSurface(stride/4, total_height);
+          }
+
+          eglBase.makeCurrent();
+
+          GlUtil.checkNoGLES2Error("Initialize fragment shader uniform values.");
+
+          GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
+          GlUtil.checkNoGLES2Error("Active texture");
+          GLES20.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, textureId);
+          GLES20.glUniformMatrix4fv(texMatrixLoc, 1, false, transformMatrix, 0);
+
+          // Draw Y */
+          GLES20.glViewport(0, 0, y_width, height);
+          GlUtil.checkNoGLES2Error("Viewport");
+          // Matrix * (1;0;0;0) / width. Note that opengl uses column major order.
+          GLES20.glUniform2f(xUnitLoc,
+              transformMatrix[0] / width,
+              transformMatrix[1] / width);
+          // Y'UV444 to RGB888, see
+          // https://en.wikipedia.org/wiki/YUV#Y.27UV444_to_RGB888_conversion
+          GLES20.glUniform4f(coeffsLoc, 0.299f, 0.587f, 0.114f, 0.0f);
+          GlUtil.checkNoGLES2Error("Binding texture and matrix");
+
+          Logging.e(TAG, "ConvertYUV: glDrawArrays");
+          GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
+          GlUtil.checkNoGLES2Error("glDrawArrays, Y");
+
+          // Draw U */
+          GLES20.glViewport(0, height, uv_width, uv_height);
+          GlUtil.checkNoGLES2Error("Viewport");
+          // Matrix * (1;0;0;0) / (2*width). Note that opengl uses column major order.
+          GLES20.glUniform2f(xUnitLoc,
+              transformMatrix[0] / (2.0f*width),
+              transformMatrix[1] / (2.0f*width));
+          /* Use ITU-R coefficients for U and V */
+          GLES20.glUniform4f(coeffsLoc, -0.169f, -0.331f, 0.499f, 0.5f);
+          GlUtil.checkNoGLES2Error("Binding texture and matrix");
+
+          Logging.e(TAG, "ConvertYUV: glDrawArrays");
+          GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
+          GlUtil.checkNoGLES2Error("glDrawArrays, U");
+
+          // Draw V */
+          GLES20.glViewport(stride/8, height, uv_width, uv_height);
+          GlUtil.checkNoGLES2Error("Viewport");
+          /* Use ITU-R coefficients for U and V */
+          GLES20.glUniform4f(coeffsLoc, 0.499f, -0.418f, -0.0813f, 0.5f);
+          GlUtil.checkNoGLES2Error("Binding texture and matrix");
+
+          Logging.e(TAG, "ConvertYUV: glDrawArrays");
+          GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
+          GlUtil.checkNoGLES2Error("glDrawArrays, V");
+
+          Logging.e(TAG, "ConvertYUV: glReadPixels");
+          GLES20.glReadPixels(0, 0, stride/4, total_height, GLES20.GL_RGBA,
+              GLES20.GL_UNSIGNED_BYTE, buf);
+          GlUtil.checkNoGLES2Error("glReadPixels");
+
+          // Unbind texture. Reportedly needed on some devices to get
+          // the texture updated from the camera.
+          GLES20.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, 0);
+        }
+        finally {
+          eglBase.detachCurrent();
+        }
+      }
+    }
+
+    public void release() {
+      synchronized(this) {
+        released = true;
+        shader.release();
+        eglBase.makeCurrent();

[magjed_webrtc, 2015/12/03 12:33:58]

shader.release() need an EGLContext current, so you need to move makeCurrent()
above.

[nisse-webrtc, 2015/12/04 09:40:34]

Done.

+        eglBase.release();
+      }
+    }
+  }
+
   private final Handler handler;
   private boolean isOwningThread;
   private final EglBase eglBase;
   private final SurfaceTexture surfaceTexture;
   private final int oesTextureId;
+  private ConvertRGBA convertRGBA;
+  private ConvertYUV convertYUV;
+
   private OnTextureFrameAvailableListener listener;
   // The possible states of this class.
   private boolean hasPendingTexture = false;
@@ -112,7 +410,7 @@ class SurfaceTextureHelper {
     this.handler = handler;
     this.isOwningThread = isOwningThread;
 
-    eglBase = new EglBase(sharedContext, EglBase.ConfigType.PIXEL_BUFFER);
+    eglBase = new EglBase(sharedContext, EglBase.CONFIG_PIXEL_BUFFER);
     eglBase.createDummyPbufferSurface();
     eglBase.makeCurrent();
 
@@ -120,6 +418,30 @@ class SurfaceTextureHelper {
     surfaceTexture = new SurfaceTexture(oesTextureId);
   }
 
+  private ConvertRGBA getConvertRGBA() {
+    // convertRGBA is assign once
+    if (convertRGBA != null)
+      return convertRGBA;
+
+    synchronized(this) {
+      if (convertRGBA == null)
+        convertRGBA = new ConvertRGBA(eglBase.getContext());
+      return convertRGBA;
+    }
+  }
+
+  private ConvertYUV getConvertYUV() {
+    // convertYUV is assign once
+    if (convertYUV != null)
+      return convertYUV;
+
+    synchronized(this) {
+      if (convertYUV == null)
+        convertYUV = new ConvertYUV(eglBase.getContext());
+      return convertYUV;
+    }
+  }
+
   /**
    *  Start to stream textures to the given |listener|.
    *  A Listener can only be set once.
@@ -207,6 +529,27 @@ class SurfaceTextureHelper {
     disconnect();
   }
 
+  public void textureToRGBA(ByteBuffer buf,
+      int width, int height, int textureId, float [] transformMatrix) {
+
+    Logging.e(TAG, "textureToRGBA called");
+
+    if (textureId != oesTextureId)
+      throw new IllegalStateException("textureToByteBuffer called with unexpected textureId");
+
+    getConvertRGBA().convert(buf, width, height, textureId, transformMatrix);
+  }
+
+  public void textureToYUV(ByteBuffer buf,
+      int width, int height, int stride, int textureId, float [] transformMatrix) {
+    Logging.e(TAG, "textureToYUV called");
+
+    if (textureId != oesTextureId)
+      throw new IllegalStateException("textureToByteBuffer called with unexpected textureId");
+
+    getConvertYUV().convert(buf, width, height, stride, textureId, transformMatrix);
+  }
+
   private void tryDeliverTextureFrame() {
     if (handler.getLooper().getThread() != Thread.currentThread()) {
       throw new IllegalStateException("Wrong thread.");
@@ -235,6 +578,12 @@ class SurfaceTextureHelper {
     if (isTextureInUse || !isQuitting) {
       throw new IllegalStateException("Unexpected release.");
     }
+    synchronized (this) {
+      if (convertRGBA != null)
+        convertRGBA.release();
+      if (convertYUV != null)
+        convertYUV.release();
+    }
     eglBase.makeCurrent();
     GLES20.glDeleteTextures(1, new int[] {oesTextureId}, 0);
     surfaceTexture.release();