feat: style transfer with openCV(ios) (#48)

## Description
This PR introduces implementation for style transfer module which is
using opencv under the hood, it allows to load images from external
sources, device storage and base64.

### Type of change
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to not work as expected)
- [ ] Documentation update (improves or adds clarity to existing
documentation)

### Tested on
- [x] iOS
- [ ] Android

### Testing instructions
<!-- Provide step-by-step instructions on how to test your changes.
Include setup details if necessary. -->

### Screenshots
<!-- Add screenshots here, if applicable -->

### Related issues
<!-- Link related issues here using #issue-number -->

### Checklist
- [x] I have performed a self-review of my code
- [ ] I have commented my code, particularly in hard-to-understand areas
- [x] I have updated the documentation accordingly
- [x] My changes generate no new warnings

### Additional notes
<!-- Include any additional information, assumptions, or context that
reviewers might need to understand this PR. -->

Author: NorbertKlockiewicz

examples/computer-vision/screens/StyleTransferScreen.tsx

@@ -34,10 +34,10 @@ export const StyleTransferScreen = ({
     }
   };
 
-  if (model.isModelLoading) {
+  if (!model.isModelReady) {
     return (
       <Spinner
-        visible={model.isModelLoading}
+        visible={!model.isModelReady}
         textContent={`Loading the model...`}
       />
     );

ios/ExecutorchLib.xcframework/ios-arm64-simulator/ExecutorchLib.framework/ExecutorchLib

@@ -6,6 +6,11 @@
 	objectVersion = 77;
 	objects = {
 
+/* Begin PBXBuildFile section */
+		55D6EA8C2D0987D2009BA408 /* ExecutorchLib.xcframework in Frameworks */ = {isa = PBXBuildFile; fileRef = 55D6EA8B2D0987D2009BA408 /* ExecutorchLib.xcframework */; };
+		55D6EA8E2D0987DF009BA408 /* opencv2.xcframework in Frameworks */ = {isa = PBXBuildFile; fileRef = 55D6EA8D2D0987DF009BA408 /* opencv2.xcframework */; };
+/* End PBXBuildFile section */
+
 /* Begin PBXCopyFilesBuildPhase section */
 		550986872CEF541900FECBB8 /* CopyFiles */ = {
 			isa = PBXCopyFilesBuildPhase;
@@ -20,6 +25,8 @@
 
 /* Begin PBXFileReference section */
 		550986892CEF541900FECBB8 /* libRnExecutorch.a */ = {isa = PBXFileReference; explicitFileType = archive.ar; includeInIndex = 0; path = libRnExecutorch.a; sourceTree = BUILT_PRODUCTS_DIR; };
+		55D6EA8B2D0987D2009BA408 /* ExecutorchLib.xcframework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.xcframework; path = ExecutorchLib.xcframework; sourceTree = "<group>"; };
+		55D6EA8D2D0987DF009BA408 /* opencv2.xcframework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.xcframework; name = opencv2.xcframework; path = ../../../opencv2.xcframework; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFileSystemSynchronizedGroupBuildPhaseMembershipExceptionSet section */
@@ -48,6 +55,8 @@
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				55D6EA8E2D0987DF009BA408 /* opencv2.xcframework in Frameworks */,
+				55D6EA8C2D0987D2009BA408 /* ExecutorchLib.xcframework in Frameworks */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -58,6 +67,7 @@
 			isa = PBXGroup;
 			children = (
 				5509868B2CEF541900FECBB8 /* RnExecutorch */,
+				55D6EA8A2D0987D2009BA408 /* Frameworks */,
 				5509868A2CEF541900FECBB8 /* Products */,
 			);
 			sourceTree = "<group>";
@@ -70,6 +80,15 @@
 			name = Products;
 			sourceTree = "<group>";
 		};
+		55D6EA8A2D0987D2009BA408 /* Frameworks */ = {
+			isa = PBXGroup;
+			children = (
+				55D6EA8D2D0987DF009BA408 /* opencv2.xcframework */,
+				55D6EA8B2D0987D2009BA408 /* ExecutorchLib.xcframework */,
+			);
+			name = Frameworks;
+			sourceTree = "<group>";
+		};
 /* End PBXGroup section */
 
 /* Begin PBXNativeTarget section */

ios/ExecutorchLib.xcframework/ios-arm64/ExecutorchLib.framework/ExecutorchLib

@@ -16,30 +16,30 @@ - (void)loadModule:(NSString *)modelSource
   if (!module) {
     module = [[ETModel alloc] init];
   }
-
+  
   [Fetcher fetchResource:[NSURL URLWithString:modelSource]
             resourceType:ResourceType::MODEL
        completionHandler:^(NSString *filePath, NSError *error) {
-         if (error) {
-           reject(@"init_module_error", @"-1", nil);
-           return;
-         }
-
-         NSNumber *result = [self->module loadModel:filePath];
-         if ([result isEqualToNumber:@(0)]) {
-           resolve(result);
-         } else {
-           NSError *error = [NSError
-               errorWithDomain:@"ETModuleErrorDomain"
-                          code:[result intValue]
-                      userInfo:@{
-                        NSLocalizedDescriptionKey : [NSString
-                            stringWithFormat:@"%ld", (long)[result longValue]]
-                      }];
-
-           reject(@"init_module_error", error.localizedDescription, error);
-         }
-       }];
+    if (error) {
+      reject(@"init_module_error", @"-1", nil);
+      return;
+    }
+    
+    NSNumber *result = [self->module loadModel:filePath];
+    if ([result isEqualToNumber:@(0)]) {
+      resolve(result);
+    } else {
+      NSError *error = [NSError
+                        errorWithDomain:@"ETModuleErrorDomain"
+                        code:[result intValue]
+                        userInfo:@{
+        NSLocalizedDescriptionKey : [NSString
+                                     stringWithFormat:@"%ld", (long)[result longValue]]
+      }];
+      
+      reject(@"init_module_error", error.localizedDescription, error);
+    }
+  }];
 }
 
 - (void)forward:(NSArray *)input
@@ -48,7 +48,7 @@ - (void)forward:(NSArray *)input
         resolve:(RCTPromiseResolveBlock)resolve
          reject:(RCTPromiseRejectBlock)reject {
   @try {
-      NSArray *result = [module forward:input shape:shape inputType:[NSNumber numberWithInt:inputType]];
+    NSArray *result = [module forward:input shape:shape inputType:[NSNumber numberWithInt:inputType]];
     resolve(result);
   } @catch (NSException *exception) {
     NSLog(@"An exception occurred: %@, %@", exception.name, exception.reason);
@@ -69,7 +69,7 @@ - (void)loadMethod:(NSString *)methodName
 }
 
 - (std::shared_ptr<facebook::react::TurboModule>)getTurboModule:
-    (const facebook::react::ObjCTurboModule::InitParams &)params {
+(const facebook::react::ObjCTurboModule::InitParams &)params {
   return std::make_shared<facebook::react::NativeETModuleSpecJSI>(params);
 }
 

ios/RnExecutorch.xcodeproj/project.pbxproj

@@ -1,7 +1,7 @@
 #import "LLM.h"
 #import <ExecutorchLib/LLaMARunner.h>
-#import "utils/ConversationManager.h"
-#import "utils/Constants.h"
+#import "utils/llms/ConversationManager.h"
+#import "utils/llms/Constants.h"
 #import "utils/Fetcher.h"
 #import "utils/LargeFileFetcher.h"
 #import <UIKit/UIKit.h>
@@ -47,77 +47,77 @@ - (void)onResult:(NSString *)token prompt:(NSString *)prompt {
 
 - (void)updateDownloadProgress:(NSNumber *)progress {
   dispatch_async(dispatch_get_main_queue(), ^{
-      [self emitOnDownloadProgress:progress];
+     [self emitOnDownloadProgress:progress];
   });
 }
 
 - (void)loadLLM:(NSString *)modelSource tokenizerSource:(NSString *)tokenizerSource systemPrompt:(NSString *)systemPrompt contextWindowLength:(double)contextWindowLength resolve:(RCTPromiseResolveBlock)resolve reject:(RCTPromiseRejectBlock)reject {
-    NSURL *modelURL = [NSURL URLWithString:modelSource];
-    NSURL *tokenizerURL = [NSURL URLWithString:tokenizerSource];
-      
-    if(self->runner || isFetching){
-      reject(@"model_already_loaded", @"Model and tokenizer already loaded", nil);
+  NSURL *modelURL = [NSURL URLWithString:modelSource];
+  NSURL *tokenizerURL = [NSURL URLWithString:tokenizerSource];
+  
+  if(self->runner || isFetching){
+    reject(@"model_already_loaded", @"Model and tokenizer already loaded", nil);
+    return;
+  }
+  
+  isFetching = YES;
+  [Fetcher fetchResource:tokenizerURL resourceType:ResourceType::TOKENIZER completionHandler:^(NSString *tokenizerFilePath, NSError *error) {
+    if(error){
+      reject(@"download_error", error.localizedDescription, nil);
       return;
     }
+    LargeFileFetcher *modelFetcher = [[LargeFileFetcher alloc] init];
+    modelFetcher.onProgress = ^(NSNumber *progress) {
+      [self updateDownloadProgress:progress];
+    };
 
-    isFetching = YES;
-    [Fetcher fetchResource:tokenizerURL resourceType:ResourceType::TOKENIZER completionHandler:^(NSString *tokenizerFilePath, NSError *error) {
-      if(error){
-        reject(@"download_error", error.localizedDescription, nil);
-        return;
-      }
-      LargeFileFetcher *modelFetcher = [[LargeFileFetcher alloc] init];
-      modelFetcher.onProgress = ^(NSNumber *progress) {
-        [self updateDownloadProgress:progress];
-      };
-      
-      modelFetcher.onFailure = ^(NSError *error){
-        reject(@"download_error", error.localizedDescription, nil);
-        return;
-      };
-      
-      modelFetcher.onFinish = ^(NSString *modelFilePath) {
-        self->runner = [[LLaMARunner alloc] initWithModelPath:modelFilePath tokenizerPath:tokenizerFilePath];
-          NSUInteger contextWindowLengthUInt = (NSUInteger)round(contextWindowLength);
-        
-        self->conversationManager = [[ConversationManager alloc] initWithNumMessagesContextWindow: contextWindowLengthUInt systemPrompt: systemPrompt];
-        self->isFetching = NO;
-        resolve(@"Model and tokenizer loaded successfully");
-        return;
-      };
+    modelFetcher.onFailure = ^(NSError *error){
+      reject(@"download_error", error.localizedDescription, nil);
+      return;
+    };
+    
+    modelFetcher.onFinish = ^(NSString *modelFilePath) {
+      self->runner = [[LLaMARunner alloc] initWithModelPath:modelFilePath tokenizerPath:tokenizerFilePath];
+      NSUInteger contextWindowLengthUInt = (NSUInteger)round(contextWindowLength);
 
-      [modelFetcher startDownloadingFileFromURL:modelURL];
-    }];
+      self->conversationManager = [[ConversationManager alloc] initWithNumMessagesContextWindow: contextWindowLengthUInt systemPrompt: systemPrompt];
+      self->isFetching = NO;
+      resolve(@"Model and tokenizer loaded successfully");
+      return;
+    };
+    
+    [modelFetcher startDownloadingFileFromURL:modelURL];
+  }];
 }
 
 
 - (void) runInference:(NSString *)input resolve:(RCTPromiseResolveBlock)resolve reject:(RCTPromiseRejectBlock)reject {
-    [conversationManager addResponse:input senderRole:ChatRole::USER];
-    NSString *prompt = [conversationManager getConversation];
-
-    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
-        NSError *error = nil;
-        [self->runner generate:prompt withTokenCallback:^(NSString *token) {
-            [self onResult:token prompt:prompt];
-        } error:&error];
-
-        // make sure to add eot token once generation is done
-        if (![self->tempLlamaResponse hasSuffix:END_OF_TEXT_TOKEN_NS]) {
-          [self onResult:END_OF_TEXT_TOKEN_NS prompt:prompt];
-        }
-
-        if (self->tempLlamaResponse) {
-          [self->conversationManager addResponse:self->tempLlamaResponse senderRole:ChatRole::ASSISTANT];
-          self->tempLlamaResponse = [NSMutableString string];
-        }
-
-        if (error) {
-            reject(@"error_in_generation", error.localizedDescription, nil);
-            return;
-        }
-        resolve(@"Inference completed successfully");
-        return;
-    });
+  [conversationManager addResponse:input senderRole:ChatRole::USER];
+  NSString *prompt = [conversationManager getConversation];
+  
+  dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
+    NSError *error = nil;
+    [self->runner generate:prompt withTokenCallback:^(NSString *token) {
+      [self onResult:token prompt:prompt];
+    } error:&error];
+    
+    // make sure to add eot token once generation is done
+    if (![self->tempLlamaResponse hasSuffix:END_OF_TEXT_TOKEN_NS]) {
+      [self onResult:END_OF_TEXT_TOKEN_NS prompt:prompt];
+    }
+    
+    if (self->tempLlamaResponse) {
+      [self->conversationManager addResponse:self->tempLlamaResponse senderRole:ChatRole::ASSISTANT];
+      self->tempLlamaResponse = [NSMutableString string];
+    }
+    
+    if (error) {
+      reject(@"error_in_generation", error.localizedDescription, nil);
+      return;
+    }
+    resolve(@"Inference completed successfully");
+    return;
+  });
 }
 
 

ios/RnExecutorch/ETModule.mm

@@ -1,10 +1,12 @@
 #import "StyleTransfer.h"
 #import "utils/Fetcher.h"
 #import "models/BaseModel.h"
+#import "utils/ETError.h"
+#import "ImageProcessor.h"
 #import <ExecutorchLib/ETModel.h>
 #import <React/RCTBridgeModule.h>
 #import "models/StyleTransferModel.h"
-#include <string>
+#import <opencv2/opencv.hpp>
 
 @implementation StyleTransfer {
   StyleTransferModel* model;
@@ -22,52 +24,34 @@ - (void)loadModule:(NSString *)modelSource
       return;
     }
 
-    NSError *error = [NSError
-                      errorWithDomain:@"StyleTransferErrorDomain"
-                      code:[errorCode intValue]
-                      userInfo:@{
-      NSLocalizedDescriptionKey : [NSString
-                                   stringWithFormat:@"%ld", (long)[errorCode longValue]]
-    }];
-    
-    reject(@"init_module_error", error.localizedDescription, error);
+    reject(@"init_module_error", [NSString
+                                  stringWithFormat:@"%ld", (long)[errorCode longValue]], nil);
     return;
   }];
 }
 
-- (std::shared_ptr<facebook::react::TurboModule>)getTurboModule:
-(const facebook::react::ObjCTurboModule::InitParams &)params {
-  return std::make_shared<facebook::react::NativeStyleTransferSpecJSI>(params);
-}
-
 - (void)forward:(NSString *)input
         resolve:(RCTPromiseResolveBlock)resolve
          reject:(RCTPromiseRejectBlock)reject {
   @try {
-    NSURL *url = [NSURL URLWithString:input];
-    NSData *data = [NSData dataWithContentsOfURL:url];
-    if (!data) {
-      reject(@"img_loading_error", @"Unable to load image data", nil);
-      return;
-    }
-    UIImage *inputImage = [UIImage imageWithData:data];
-    
-    UIImage* result = [model runModel:inputImage];
-    
-    // save img to tmp dir, return URI
-    NSString *outputPath = [NSTemporaryDirectory() stringByAppendingPathComponent:[@"test" stringByAppendingString:@".png"]];
-    if ([UIImagePNGRepresentation(result) writeToFile:outputPath atomically:YES]) {
-      NSURL *fileURL = [NSURL fileURLWithPath:outputPath];
-      resolve([fileURL absoluteString]);
-    } else {
-      reject(@"img_write_error", @"Failed to write processed image to file", nil);
-    }
+    cv::Mat image = [ImageProcessor readImage:input];
+    cv::Mat resultImage = [model runModel:image];
 
+    NSString* tempFilePath = [ImageProcessor saveToTempFile:resultImage];
+    resolve(tempFilePath);
+    return;
   } @catch (NSException *exception) {
     NSLog(@"An exception occurred: %@, %@", exception.name, exception.reason);
-    reject(@"result_error", [NSString stringWithFormat:@"%@", exception.reason],
+    reject(@"forward_error", [NSString stringWithFormat:@"%@", exception.reason],
            nil);
+    return;
   }
 }
 
+
+- (std::shared_ptr<facebook::react::TurboModule>)getTurboModule:
+(const facebook::react::ObjCTurboModule::InitParams &)params {
+  return std::make_shared<facebook::react::NativeStyleTransferSpecJSI>(params);
+}
+
 @end

ios/RnExecutorch/LLM.mm

@@ -1,14 +1,14 @@
 #import <Foundation/Foundation.h>
 #import <UIKit/UIKit.h>
-#import "ETModel.h"
+#import "ExecutorchLib/ETModel.h"
 
 @interface BaseModel : NSObject
 {
 @protected
-    ETModel *module;
+  ETModel *module;
 }
 
-- (NSArray *)forward:(NSArray *)input shape:(NSArray *)shape inputType:(NSNumber *)inputType error:(NSError **)error;
+- (NSArray *)forward:(NSArray *)input;
 - (void)loadModel:(NSURL *)modelURL completion:(void (^)(BOOL success, NSNumber *code))completion;
 
 @end