Added iOS test for quantized embedding

mediapipe/tasks/ios/test/text/text_embedder/MPPTextEmbedderTests.m

@@ -23,7 +23,7 @@ static NSString *const kText1 = @"it's a charming and often affecting journey";
 static NSString *const kText2 = @"what a great and fantastic trip";
 static NSString *const kExpectedErrorDomain = @"com.google.mediapipe.tasks";
 static const float kFloatDiffTolerance = 1e-4;
-static const float kDoubleDiffTolerance = 1e-4;
+static const float kSimilarityDiffTolerance = 1e-4;
 
 #define AssertEqualErrors(error, expectedError)                                               \
   XCTAssertNotNil(error);                                                                     \
@@ -38,13 +38,24 @@ static const float kDoubleDiffTolerance = 1e-4;
   XCTAssertNotNil(textEmbedderResult.embeddingResult);              \
   XCTAssertEqual(textEmbedderResult.embeddingResult.embeddings.count, 1);
 
-#define AssertEmbeddingIsFloat(embedding)    \
+#define AssertEmbeddingType(embedding, quantized)    \
+  if (quantized) { \
+    XCTAssertNil(embedding.floatEmbedding);                                              \
+    XCTAssertNotNil(embedding.quantizedEmbedding);   \
+  } \
+  else { \
     XCTAssertNotNil(embedding.floatEmbedding); \
-  XCTAssertNil(embedding.quantizedEmbedding);
+    XCTAssertNil(embedding.quantizedEmbedding);\
+  }           
 
-#define AssertFloatEmbeddingHasExpectedValues(floatEmbedding, expectedLength, expectedFirstValue) \
+#define AssertEmbeddingHasExpectedValues(embedding, expectedLength, expectedFirstValue, quantize) \
-  XCTAssertEqual(floatEmbedding.count, expectedLength);                                           \
+  XCTAssertEqual(embedding.count, expectedLength);                                           \
-  XCTAssertEqualWithAccuracy(floatEmbedding[0].floatValue, expectedFirstValue, kFloatDiffTolerance);
+  if (quantize) { \
+     XCTAssertEqual(embedding[0].charValue, expectedFirstValue); \
+  } \
+  else { \
+    XCTAssertEqualWithAccuracy(embedding[0].floatValue, expectedFirstValue, kFloatDiffTolerance); \
+  } \
 
 @interface MPPTextEmbedderTests : XCTestCase
 @end
@@ -69,15 +80,55 @@ static const float kDoubleDiffTolerance = 1e-4;
   return textEmbedder;
 }
 
+- (MPPTextEmbedderOptions *)textEmbedderOptionsWithModelName:(NSString *)modelName {
+  NSString *modelPath = [self filePathWithName:modelName extension:@"tflite"];
+  MPPTextEmbedderOptions *textEmbedderOptions = [[MPPTextEmbedderOptions alloc] init];
+  textEmbedderOptions.baseOptions.modelAssetPath = modelPath;
+
+  return textEmbedderOptions;
+}
+
 - (NSArray<NSNumber *> *)assertFloatEmbeddingResultsOfEmbedText:(NSString *)text
                                               usingTextEmbedder:(MPPTextEmbedder *)textEmbedder
                                                        hasCount:(NSUInteger)embeddingCount
                                                      firstValue:(float)firstValue {
   MPPTextEmbedderResult *embedderResult = [textEmbedder embedText:text error:nil];
   AssertTextEmbedderResultHasOneEmbedding(embedderResult);
-  AssertEmbeddingIsFloat(embedderResult.embeddingResult.embeddings[0]);
+  
-  AssertFloatEmbeddingHasExpectedValues(embedderResult.embeddingResult.embeddings[0].floatEmbedding,
+  AssertEmbeddingType(
-                                        embeddingCount, firstValue);
+    embedderResult.embeddingResult.embeddings[0], // embedding
+    NO                                            // quantized
+  );
+  
+  AssertEmbeddingHasExpectedValues(
+    embedderResult.embeddingResult.embeddings[0].floatEmbedding, // embedding
+    embeddingCount,                                              // expectedLength              
+    firstValue,                                                  // expectedFirstValue
+    NO                                                           // quantize
+  );
+  
+  return embedderResult.embeddingResult.embeddings[0];
+}
+
+- (NSArray<NSNumber *>*)assertQuantizedEmbeddingResultsOfEmbedText:(NSString *)text
+                usingTextEmbedder:(MPPTextEmbedder *)textEmbedder
+                   hasCount:(NSUInteger)embeddingCount 
+                   firstValue:(char)firstValue {
+  MPPTextEmbedderResult *embedderResult = [textEmbedder embedText:text error:nil];
+  AssertTextEmbedderResultHasOneEmbedding(embedderResult);
+  
+  AssertEmbeddingType(
+    embedderResult.embeddingResult.embeddings[0], // embedding
+    YES                                           // quantized
+  );
+  
+  AssertEmbeddingHasExpectedValues(
+    embedderResult.embeddingResult.embeddings[0].quantizedEmbedding, // embedding
+    embeddingCount,                                                  // expectedLength              
+    firstValue,                                                      // expectedFirstValue
+    YES                                                              // quantize
+  );
+  
   return embedderResult.embeddingResult.embeddings[0];
 }
 
@@ -97,7 +148,10 @@ static const float kDoubleDiffTolerance = 1e-4;
                    @"INVALID_ARGUMENT: ExternalFile must specify at least one of 'file_content', "
                    @"'file_name', 'file_pointer_meta' or 'file_descriptor_meta'."
              }];
-  AssertEqualErrors(error, expectedError);
+  AssertEqualErrors(
+    error,        // error        
+    expectedError // expectedError
+  );
 }
 
 - (void)testEmbedWithBertSucceeds {
@@ -116,7 +170,7 @@ static const float kDoubleDiffTolerance = 1e-4;
   NSNumber *cosineSimilarity = [MPPTextEmbedder cosineSimilarityBetweenEmbedding1:embedding1
                                                                     andEmbedding2:embedding2
                                                                             error:nil];
-  XCTAssertEqualWithAccuracy(cosineSimilarity.doubleValue, 0.96386, kDoubleDiffTolerance);
+  XCTAssertEqualWithAccuracy(cosineSimilarity.doubleValue, 0.96386, kSimilarityDiffTolerance);
 }
 
 - (void)testEmbedWithRegexSucceeds {
@@ -136,7 +190,7 @@ static const float kDoubleDiffTolerance = 1e-4;
   NSNumber *cosineSimilarity = [MPPTextEmbedder cosineSimilarityBetweenEmbedding1:embedding1
                                                                     andEmbedding2:embedding2
                                                                             error:nil];
-  XCTAssertEqualWithAccuracy(cosineSimilarity.doubleValue, 0.999937f, kDoubleDiffTolerance);
+  XCTAssertEqualWithAccuracy(cosineSimilarity.doubleValue, 0.999937f, kSimilarityDiffTolerance);
 }
 
 - (void)testEmbedWithBertAndDifferentThemesSucceeds {
@@ -163,7 +217,28 @@ static const float kDoubleDiffTolerance = 1e-4;
                                                                             error:nil];
 
   // TODO: The similarity should likely be lower
-  XCTAssertEqualWithAccuracy(cosineSimilarity.doubleValue, 0.963203f, kDoubleDiffTolerance);
+  XCTAssertEqualWithAccuracy(cosineSimilarity.doubleValue, 0.963203f, kSimilarityDiffTolerance);
+}
+
+- (void)testEmbedWithQuantizeSucceeds {
+  MPPTextEmbedderOptions *options =
+      [self textEmbedderOptionsWithModelName:kBertTextEmbedderModelName];
+  options.quantize = YES;
+
+  MPPTextEmbedder *textEmbedder = [[MPPTextEmbedder alloc] initWithOptions:options error:nil];
+  XCTAssertNotNil(textEmbedder);
+
+  MPPEmbedding *embedding1 = [self assertQuantizedEmbeddingResultsOfEmbedText:@"it's a charming and often affecting journey"
+                usingTextEmbedder:textEmbedder
+                   hasCount:512
+                   firstValue:127];
+
+  MPPEmbedding *embedding2 = [self assertQuantizedEmbeddingResultsOfEmbedText:@"what a great and fantastic trip"
+                usingTextEmbedder:textEmbedder
+                   hasCount:512
+                   firstValue:127];
+  NSNumber *cosineSimilarity = [MPPTextEmbedder cosineSimilarityBetweenEmbedding1:embedding1 andEmbedding2:embedding2 error:nil];  
+  XCTAssertEqualWithAccuracy(cosineSimilarity.doubleValue, 0.864113, kSimilarityDiffTolerance); 
 }
 
 @end