Add SSIM support to AndroidTestUtil.

PiperOrigin-RevId: 431479473

library/transformer/src/androidTest/java/com/google/android/exoplayer2/transformer/AndroidTestUtil.java

@@ -58,19 +58,32 @@ public final class AndroidTestUtil {
    * @param transformer The {@link Transformer} that performs the transformation.
    * @param uriString The uri (as a {@link String}) that will be transformed.
    * @param timeoutSeconds The transformer timeout. An exception is thrown if this is exceeded.
+   * @param calculateSsim Whether to include SSIM in the {@link TestTransformationResult}. The
+   *     calculation involves decoding and comparing both the input and the output video.
+   *     Consequently this calculation is not cost-free. Requires the input and output video to be
+   *     the same size.
    * @return The {@link TestTransformationResult}.
    * @throws Exception The cause of the transformation not completing.
    */
   public static TestTransformationResult runTransformer(
-      Context context, String testId, Transformer transformer, String uriString, int timeoutSeconds)
+      Context context,
+      String testId,
+      Transformer transformer,
+      String uriString,
+      int timeoutSeconds,
+      boolean calculateSsim)
       throws Exception {
     JSONObject resultJson = new JSONObject();
     try {
       TestTransformationResult testTransformationResult =
-          runTransformerInternal(context, testId, transformer, uriString, timeoutSeconds);
+          runTransformerInternal(
+              context, testId, transformer, uriString, timeoutSeconds, calculateSsim);
       resultJson.put(
           "transformationResult",
           getTransformationResultJson(testTransformationResult.transformationResult));
+      if (testTransformationResult.ssim != TestTransformationResult.SSIM_UNSET) {
+        resultJson.put("ssim", testTransformationResult.ssim);
+      }
       return testTransformationResult;
     } catch (Exception e) {
       resultJson.put("exception", getExceptionJson(e));
@@ -81,7 +94,12 @@ public final class AndroidTestUtil {
   }
 
   private static TestTransformationResult runTransformerInternal(
-      Context context, String testId, Transformer transformer, String uriString, int timeoutSeconds)
+      Context context,
+      String testId,
+      Transformer transformer,
+      String uriString,
+      int timeoutSeconds,
+      boolean calculateSsim)
       throws Exception {
     AtomicReference<@NullableType TransformationException> transformationExceptionReference =
         new AtomicReference<>();
@@ -150,7 +168,15 @@ public final class AndroidTestUtil {
             .setFileSizeBytes(outputVideoFile.length())
             .build();
 
-    return new TestTransformationResult(transformationResult, outputVideoFile.getPath());
+    if (calculateSsim) {
+      return new TestTransformationResult(
+          transformationResult,
+          outputVideoFile.getPath(),
+          SsimHelper.calculate(
+              context, /* expectedVideoPath= */ uriString, outputVideoFile.getPath()));
+    } else {
+      return new TestTransformationResult(transformationResult, outputVideoFile.getPath());
+    }
   }
 
   private static void writeTestSummaryToFile(Context context, String testId, JSONObject resultJson)

library/transformer/src/androidTest/java/com/google/android/exoplayer2/transformer/SsimHelper.java

@@ -82,18 +82,17 @@ public final class SsimHelper {
   /**
    * Returns the mean SSIM score between the expected and the actual video.
    *
+   * <p>The method compares every {@link #DEFAULT_COMPARISON_INTERVAL n-th} frame from both videos.
+   *
    * @param context The {@link Context}.
    * @param expectedVideoPath The path to the expected video file, must be in {@link
    *     Context#getAssets() Assets}.
    * @param actualVideoPath The path to the actual video file.
-   * @param comparisonInterval The number of frames between the frames selected for comparison by
-   *     SSIM.
    * @throws IOException When unable to open the provided video paths.
    */
-  public static double calculate(
+  public static double calculate(Context context, String expectedVideoPath, String actualVideoPath)
-      Context context, String expectedVideoPath, String actualVideoPath, int comparisonInterval)
       throws IOException, InterruptedException {
-    return new SsimHelper(context, expectedVideoPath, actualVideoPath, comparisonInterval)
+    return new SsimHelper(context, expectedVideoPath, actualVideoPath, DEFAULT_COMPARISON_INTERVAL)
         .startCalculation();
   }
 

library/transformer/src/androidTest/java/com/google/android/exoplayer2/transformer/TestTransformationResult.java

@@ -17,11 +17,22 @@ package com.google.android.exoplayer2.transformer;
 
 /** A test only class for holding additional details alongside a {@link TransformationResult}. */
 public class TestTransformationResult {
+  /** Represents an unset or unknown SSIM score. */
+  public static final double SSIM_UNSET = -1.0d;
+
   public final TransformationResult transformationResult;
   public final String filePath;
+  /** The SSIM score of the transformation, {@link #SSIM_UNSET} if unavailable. */
+  public final double ssim;
 
   public TestTransformationResult(TransformationResult transformationResult, String filePath) {
+    this(transformationResult, filePath, /* ssim= */ SSIM_UNSET);
+  }
+
+  public TestTransformationResult(
+      TransformationResult transformationResult, String filePath, double ssim) {
     this.transformationResult = transformationResult;
     this.filePath = filePath;
+    this.ssim = ssim;
   }
 }

library/transformer/src/androidTest/java/com/google/android/exoplayer2/transformer/TransformerEndToEndTest.java

@@ -59,7 +59,8 @@ public class TransformerEndToEndTest {
         /* testId= */ "videoTranscoding_completesWithConsistentFrameCount",
         transformer,
         VP9_VIDEO_URI_STRING,
-        /* timeoutSeconds= */ 120);
+        /* timeoutSeconds= */ 120,
+        /* calculateSsim= */ false);
 
     FrameCountingMuxer frameCountingMuxer =
         checkNotNull(muxerFactory.getLastFrameCountingMuxerCreated());
@@ -92,7 +93,8 @@ public class TransformerEndToEndTest {
         /* testId= */ "videoEditing_completesWithConsistentFrameCount",
         transformer,
         AVC_VIDEO_URI_STRING,
-        /* timeoutSeconds= */ 120);
+        /* timeoutSeconds= */ 120,
+        /* calculateSsim= */ false);
 
     FrameCountingMuxer frameCountingMuxer =
         checkNotNull(muxerFactory.getLastFrameCountingMuxerCreated());

library/transformer/src/androidTest/java/com/google/android/exoplayer2/transformer/mh/RemoveAudioTransformationTest.java

@@ -40,6 +40,7 @@ public class RemoveAudioTransformationTest {
         /* testId= */ "removeAudioTransform",
         transformer,
         MP4_ASSET_WITH_INCREASING_TIMESTAMPS_URI_STRING,
-        /* timeoutSeconds= */ 120);
+        /* timeoutSeconds= */ 120,
+        /* calculateSsim= */ false);
   }
 }

library/transformer/src/androidTest/java/com/google/android/exoplayer2/transformer/mh/RemoveVideoTransformationTest.java

@@ -37,6 +37,7 @@ public class RemoveVideoTransformationTest {
         /* testId= */ "removeVideoTransform",
         transformer,
         MP4_ASSET_URI_STRING,
-        /* timeoutSeconds= */ 120);
+        /* timeoutSeconds= */ 120,
+        /* calculateSsim= */ false);
   }
 }

library/transformer/src/androidTest/java/com/google/android/exoplayer2/transformer/mh/RepeatedTranscodeTransformationTest.java

@@ -62,7 +62,8 @@ public final class RepeatedTranscodeTransformationTest {
               /* testId= */ "repeatedTranscode_givesConsistentLengthOutput_" + i,
               transformer,
               AndroidTestUtil.REMOTE_MP4_10_SECONDS_H264_MP3_URI_STRING,
-              /* timeoutSeconds= */ 120);
+              /* timeoutSeconds= */ 120,
+              /* calculateSsim= */ false);
       differentOutputSizesBytes.add(checkNotNull(testResult.transformationResult.fileSizeBytes));
     }
 
@@ -96,7 +97,8 @@ public final class RepeatedTranscodeTransformationTest {
               /* testId= */ "repeatedTranscodeNoAudio_givesConsistentLengthOutput_" + i,
               transformer,
               AndroidTestUtil.REMOTE_MP4_10_SECONDS_H264_MP3_URI_STRING,
-              /* timeoutSeconds= */ 120);
+              /* timeoutSeconds= */ 120,
+              /* calculateSsim= */ false);
       differentOutputSizesBytes.add(checkNotNull(testResult.transformationResult.fileSizeBytes));
     }
 
@@ -125,7 +127,8 @@ public final class RepeatedTranscodeTransformationTest {
               /* testId= */ "repeatedTranscodeNoVideo_givesConsistentLengthOutput_" + i,
               transformer,
               AndroidTestUtil.REMOTE_MP4_10_SECONDS_H264_MP3_URI_STRING,
-              /* timeoutSeconds= */ 120);
+              /* timeoutSeconds= */ 120,
+              /* calculateSsim= */ false);
       differentOutputSizesBytes.add(checkNotNull(testResult.transformationResult.fileSizeBytes));
     }
 

library/transformer/src/androidTest/java/com/google/android/exoplayer2/transformer/mh/SefTransformationTest.java

@@ -53,6 +53,7 @@ public class SefTransformationTest {
         /* testId = */ "sefTransform",
         transformer,
         SEF_ASSET_URI_STRING,
-        /* timeoutSeconds= */ 120);
+        /* timeoutSeconds= */ 120,
+        /* calculateSsim= */ false);
   }
 }

library/transformer/src/androidTest/java/com/google/android/exoplayer2/transformer/mh/SetTransformationMatrixTransformationTest.java

@@ -48,6 +48,7 @@ public class SetTransformationMatrixTransformationTest {
         /* testId= */ "setTransformationMatrixTransform",
         transformer,
         REMOTE_MP4_10_SECONDS_URI_STRING,
-        /* timeoutSeconds= */ 120);
+        /* timeoutSeconds= */ 120,
+        /* calculateSsim= */ false);
   }
 }

library/transformer/src/androidTest/java/com/google/android/exoplayer2/transformer/mh/TranscodeQualityTest.java

@@ -23,7 +23,6 @@ import android.content.Context;
 import androidx.test.core.app.ApplicationProvider;
 import androidx.test.ext.junit.runners.AndroidJUnit4;
 import com.google.android.exoplayer2.transformer.AndroidTestUtil;
-import com.google.android.exoplayer2.transformer.SsimHelper;
 import com.google.android.exoplayer2.transformer.TestTransformationResult;
 import com.google.android.exoplayer2.transformer.TransformationRequest;
 import com.google.android.exoplayer2.transformer.Transformer;
@@ -52,14 +51,9 @@ public final class TranscodeQualityTest {
             /* testId= */ "singleTranscode_ssim",
             transformer,
             AndroidTestUtil.MP4_ASSET_URI_STRING,
-            /* timeoutSeconds= */ 120);
+            /* timeoutSeconds= */ 120,
+            /* calculateSsim= */ true);
 
-    assertThat(
+    assertThat(result.ssim).isGreaterThan(0.95);
-            SsimHelper.calculate(
-                context,
-                AndroidTestUtil.MP4_ASSET_URI_STRING,
-                result.filePath,
-                SsimHelper.DEFAULT_COMPARISON_INTERVAL))
-        .isGreaterThan(0.95);
   }
 }

library/transformer/src/androidTest/java/com/google/android/exoplayer2/transformer/mh/TransformationTest.java

@@ -40,6 +40,7 @@ public class TransformationTest {
         /* testId= */ "transform",
         transformer,
         MP4_ASSET_WITH_INCREASING_TIMESTAMPS_URI_STRING,
-        /* timeoutSeconds= */ 120);
+        /* timeoutSeconds= */ 120,
+        /* calculateSsim= */ false);
   }
 }