Store LUT bitmap as texture with processor creation.

* Before this CL, the texture was stored during the construction of the LUT processor. This failed since if one creates a list of GlEffects on the application thread, the texture will get stored in the application thread during the effect creation and not on the GL thread, which executes the FrameProcessors.
* This is an issue since the executing thread then can't index from the texture stored on a different thread.

PiperOrigin-RevId: 476388021
(cherry picked from commit f745c6ee0ea0b610cfdf6a146818b0da7d06326a)

google3/third_party/java_src/android_libs/media/libraries/effect/src/main/java/androidx/media3/effect/ColorLut.java

@@ -17,6 +17,7 @@
 package androidx.media3.effect;
 
 import android.content.Context;
+import androidx.annotation.WorkerThread;
 import androidx.media3.common.FrameProcessingException;
 import com.google.android.exoplayer2.util.GlUtil;
 
@@ -38,7 +39,9 @@ public interface ColorLut extends GlEffect {
   /** Releases the OpenGL texture of the LUT. */
   void release() throws GlUtil.GlException;
 
+  /** This method must be executed on the same thread as other GL commands. */
   @Override
+  @WorkerThread
   default ColorLutProcessor toGlTextureProcessor(Context context, boolean useHdr)
       throws FrameProcessingException {
     return new ColorLutProcessor(context, /* colorLut= */ this, useHdr);

google3/third_party/java_src/android_libs/media/libraries/effect/src/main/java/androidx/media3/effect/SingleColorLut.java

@@ -24,13 +24,14 @@ import android.graphics.Bitmap;
 import android.opengl.GLES20;
 import android.opengl.GLUtils;
 import androidx.media3.common.FrameProcessingException;
+import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.util.GlUtil;
 import com.google.android.exoplayer2.util.Util;
 
 /** Transforms the colors of a frame by applying the same color lookup table to each frame. */
 public class SingleColorLut implements ColorLut {
-  private final int lutTextureId;
-  private final int length;
+  private final Bitmap lut;
+  private int lutTextureId;
 
   /**
    * Creates a new instance.
@@ -38,7 +39,7 @@ public class SingleColorLut implements ColorLut {
    * <p>{@code lutCube} needs to be a {@code N x N x N} cube and each element is an integer
    * representing a color using the {@link Bitmap.Config#ARGB_8888} format.
    */
-  public static SingleColorLut createFromCube(int[][][] lutCube) throws GlUtil.GlException {
+  public static SingleColorLut createFromCube(int[][][] lutCube) {
     checkArgument(
         lutCube.length > 0 && lutCube[0].length > 0 && lutCube[0][0].length > 0,
         "LUT must have three dimensions.");
@@ -58,7 +59,7 @@ public class SingleColorLut implements ColorLut {
    * N^2}. Each element must be an integer representing a color using the {@link
    * Bitmap.Config#ARGB_8888} format.
    */
-  public static SingleColorLut createFromBitmap(Bitmap lut) throws GlUtil.GlException {
+  public static SingleColorLut createFromBitmap(Bitmap lut) {
     checkArgument(
         lut.getWidth() * lut.getWidth() == lut.getHeight(),
         Util.formatInvariant(
@@ -70,18 +71,9 @@ public class SingleColorLut implements ColorLut {
     return new SingleColorLut(lut);
   }
 
-  private SingleColorLut(Bitmap lut) throws GlUtil.GlException {
-    length = lut.getWidth();
-    lutTextureId = storeLutAsTexture(lut);
-  }
-
-  private static int storeLutAsTexture(Bitmap bitmap) throws GlUtil.GlException {
-    int lutTextureId =
-        GlUtil.createTexture(
-            bitmap.getWidth(), bitmap.getHeight(), /* useHighPrecisionColorComponents= */ false);
-    GLUtils.texImage2D(GLES20.GL_TEXTURE_2D, /* level= */ 0, bitmap, /* border= */ 0);
-    GlUtil.checkGlError();
-    return lutTextureId;
+  private SingleColorLut(Bitmap lut) {
+    this.lut = lut;
+    lutTextureId = Format.NO_VALUE;
   }
 
   /**
@@ -134,14 +126,19 @@ public class SingleColorLut implements ColorLut {
         Bitmap.Config.ARGB_8888);
   }
 
+  /** Must be called after {@link #toGlTextureProcessor(Context, boolean)}. */
   @Override
   public int getLutTextureId(long presentationTimeUs) {
+    checkState(
+        lutTextureId != Format.NO_VALUE,
+        "The LUT has not been stored as a texture in OpenGL yet. You must to call"
+            + " #toGlTextureProcessor() first.");
     return lutTextureId;
   }
 
   @Override
   public int getLength(long presentationTimeUs) {
-    return length;
+    return lut.getWidth();
   }
 
   @Override
@@ -153,6 +150,22 @@ public class SingleColorLut implements ColorLut {
   public ColorLutProcessor toGlTextureProcessor(Context context, boolean useHdr)
       throws FrameProcessingException {
     checkState(!useHdr, "HDR is currently not supported.");
+
+    try {
+      lutTextureId = storeLutAsTexture(lut);
+    } catch (GlUtil.GlException e) {
+      throw new FrameProcessingException("Could not store the LUT as a texture.", e);
+    }
+
     return new ColorLutProcessor(context, /* colorLut= */ this, useHdr);
   }
+
+  private static int storeLutAsTexture(Bitmap bitmap) throws GlUtil.GlException {
+    int lutTextureId =
+        GlUtil.createTexture(
+            bitmap.getWidth(), bitmap.getHeight(), /* useHighPrecisionColorComponents= */ false);
+    GLUtils.texImage2D(GLES20.GL_TEXTURE_2D, /* level= */ 0, bitmap, /* border= */ 0);
+    GlUtil.checkGlError();
+    return lutTextureId;
+  }
 }

library/common/src/main/java/com/google/android/exoplayer2/util/GlUtil.java

@@ -355,12 +355,15 @@ public final class GlUtil {
     // TODO(b/201293185): Consider handling adjustments for sizes > GL_MAX_TEXTURE_SIZE
     //  (ex. downscaling appropriately) in a texture processor instead of asserting incorrect
     //  values.
-
     // For valid GL sizes, see:
     // https://www.khronos.org/registry/OpenGL-Refpages/es2.0/xhtml/glTexImage2D.xml
     int[] maxTextureSizeBuffer = new int[1];
     GLES20.glGetIntegerv(GLES20.GL_MAX_TEXTURE_SIZE, maxTextureSizeBuffer, 0);
     int maxTextureSize = maxTextureSizeBuffer[0];
+    checkState(
+        maxTextureSize > 0,
+        "Create a OpenGL context first or run the GL methods on an OpenGL thread.");
+
     if (width < 0 || height < 0) {
       throw new GlException("width or height is less than 0");
     }