feat : 다수결 스무딩 적용

HalfFifty_BE/src/main/java/HalfFifty/HalfFifty_BE/HalfFiftyBeApplication.java

@@ -2,8 +2,10 @@
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.scheduling.annotation.EnableScheduling;
 
 @SpringBootApplication
+@EnableScheduling
 public class HalfFiftyBeApplication {
 
 	public static void main(String[] args) {

HalfFifty_BE/src/main/java/HalfFifty/HalfFifty_BE/translation/bean/FrameBufferBean.java

@@ -0,0 +1,119 @@
+package HalfFifty.HalfFifty_BE.translation.bean;
+
+import HalfFifty.HalfFifty_BE.translation.domain.DTO.FrameBufferResult;
+import org.springframework.scheduling.annotation.Scheduled;
+import org.springframework.stereotype.Component;
+
+import java.time.LocalDateTime;
+import java.util.*;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+
+@Component
+public class FrameBufferBean {
+    private final Map<UUID, BufferData> userFrameBuffers = new ConcurrentHashMap<>();
+    private final int BUFFER_SIZE = 5;
+    private final int REQUIRED_MATCHES = 3;
+    private final int TIMEOUT_MINUTES = 10; // 10분 후 자동 삭제
+
+    // 버퍼 데이터와 타임스탬프를 함께 저장하는 내부 클래스
+    private static class BufferData {
+        List<String> buffer;
+        LocalDateTime lastAccess;
+
+        BufferData() {
+            this.buffer = new ArrayList<>();
+            this.lastAccess = LocalDateTime.now();
+        }
+
+        void updateAccess() {
+            this.lastAccess = LocalDateTime.now();
+        }
+    }
+
+    public FrameBufferResult addFrame(UUID userId, String predictedWord) {
+        if (userId == null || predictedWord == null || predictedWord.trim().isEmpty()) {
+            return new FrameBufferResult(false, null, 0, BUFFER_SIZE);
+        }
+
+        BufferData bufferData = userFrameBuffers.computeIfAbsent(userId, k -> new BufferData());
+        bufferData.updateAccess(); // 접근 시간 갱신
+
+        List<String> buffer = bufferData.buffer;
+        buffer.add(predictedWord.trim());
+
+        // 버퍼 크기 제한
+        if (buffer.size() > BUFFER_SIZE) {
+            buffer.remove(0);
+        }
+
+        // 다수결 확인
+        if (buffer.size() >= BUFFER_SIZE) {
+            return checkMajority(buffer, userId);
+        }
+
+        return new FrameBufferResult(false, null, buffer.size(), BUFFER_SIZE);
+    }
+
+    private FrameBufferResult checkMajority(List<String> buffer, UUID userId) {
+        try {
+            Map<String, Long> wordCounts = buffer.stream()
+                    .filter(Objects::nonNull)
+                    .filter(word -> !word.trim().isEmpty())
+                    .collect(Collectors.groupingBy(Function.identity(), Collectors.counting()));
+
+            Optional<Map.Entry<String, Long>> mostFrequent = wordCounts.entrySet().stream()
+                    .max(Map.Entry.comparingByValue());
+
+            if (mostFrequent.isPresent() && mostFrequent.get().getValue() >= REQUIRED_MATCHES) {
+                // 확정되면 해당 사용자의 버퍼 초기화
+                clearBuffer(userId);
+                return new FrameBufferResult(true, mostFrequent.get().getKey(), BUFFER_SIZE, BUFFER_SIZE);
+            }
+
+            return new FrameBufferResult(false, null, buffer.size(), BUFFER_SIZE);
+
+        } catch (Exception e) {
+            System.err.println("Error in checkMajority: " + e.getMessage());
+            return new FrameBufferResult(false, null, buffer.size(), BUFFER_SIZE);
+        }
+    }
+
+    public void clearBuffer(UUID userId) {
+        if (userId != null) {
+            userFrameBuffers.remove(userId);
+        }
+    }
+
+    public List<String> getBuffer(UUID userId) {
+        if (userId == null) {
+            return new ArrayList<>();
+        }
+        BufferData bufferData = userFrameBuffers.get(userId);
+        return bufferData != null ? new ArrayList<>(bufferData.buffer) : new ArrayList<>();
+    }
+
+    // 메모리 누수 방지: 10분마다 오래된 버퍼 자동 삭제
+    @Scheduled(fixedRate = 600000) // 10분마다 실행
+    public void cleanupOldBuffers() {
+        LocalDateTime cutoffTime = LocalDateTime.now().minusMinutes(TIMEOUT_MINUTES);
+
+        Iterator<Map.Entry<UUID, BufferData>> iterator = userFrameBuffers.entrySet().iterator();
+        int removedCount = 0;
+
+        while (iterator.hasNext()) {
+            Map.Entry<UUID, BufferData> entry = iterator.next();
+            if (entry.getValue().lastAccess.isBefore(cutoffTime)) {
+                iterator.remove();
+                removedCount++;
+            }
+        }
+
+        if (removedCount > 0) {
+            System.out.println("정리된 비활성 버퍼 개수: " + removedCount);
+        }
+
+        System.out.println("현재 활성 버퍼 개수: " + userFrameBuffers.size());
+    }
+}

HalfFifty_BE/src/main/java/HalfFifty/HalfFifty_BE/translation/controller/TranslationController.java

@@ -3,6 +3,7 @@
 import HalfFifty.HalfFifty_BE.translation.domain.DTO.RequestSignLanguageDTO;
 import HalfFifty.HalfFifty_BE.translation.domain.DTO.RequestTranslationDeleteDTO;
 import HalfFifty.HalfFifty_BE.translation.domain.DTO.ResponseTranslationGetDTO;
+import HalfFifty.HalfFifty_BE.translation.domain.DTO.TranslationStatusResponse;
 import HalfFifty.HalfFifty_BE.translation.service.TranslationService;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
@@ -24,19 +25,22 @@ public TranslationController(TranslationService translationService) {
     // 수화 번역 API
     @PostMapping
     public ResponseEntity<Map<String, Object>> translateSignLanguage(@RequestBody RequestSignLanguageDTO requestSignLanguageDTO) {
-        // 번역된 데이터 가져오기
-        ResponseTranslationGetDTO responseTranslationGetDTO = translationService.signLanguageTranslation(requestSignLanguageDTO);
+        TranslationStatusResponse response = translationService.getTranslationStatus(requestSignLanguageDTO);
 
-        // 번역 성공 여부 확인
-        boolean success = responseTranslationGetDTO != null;
-
-        // 응답 데이터 구성
         Map<String, Object> responseMap = new HashMap<>();
-        responseMap.put("success", success);
-        responseMap.put("message", success ? "수화 번역 성공" : "수화 번역 실패");
-        responseMap.put("translationId", success ? responseTranslationGetDTO.getTranslationId() : null);
-        responseMap.put("translatedWord", success ? responseTranslationGetDTO.getTranslationWord() : null);
-        responseMap.put("probability", success ? responseTranslationGetDTO.getProbability() : null);
+        responseMap.put("success", "success".equals(response.getStatus()));
+        responseMap.put("message", response.getMessage());
+        responseMap.put("status", response.getStatus());
+        responseMap.put("translationId", null);
+        responseMap.put("translatedWord", null);
+        responseMap.put("probability", null);
+
+        if ("success".equals(response.getStatus()) && response.getData() != null) {
+            ResponseTranslationGetDTO data = response.getData();
+            responseMap.put("translationId", data.getTranslationId());
+            responseMap.put("translatedWord", data.getTranslationWord());
+            responseMap.put("probability", data.getProbability());
+        }
 
         return ResponseEntity.status(HttpStatus.OK).body(responseMap);
     }

HalfFifty_BE/src/main/java/HalfFifty/HalfFifty_BE/translation/domain/DTO/FrameBufferResult.java

@@ -0,0 +1,15 @@
+package HalfFifty.HalfFifty_BE.translation.domain.DTO;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+@Data
+@AllArgsConstructor
+@NoArgsConstructor
+public class FrameBufferResult {
+    private boolean confirmed;        // 확정 여부
+    private String confirmedWord;     // 확정된 단어
+    private int currentBufferSize;    // 현재 버퍼 크기
+    private int requiredBufferSize;   // 필요한 버퍼 크기
+}

HalfFifty_BE/src/main/java/HalfFifty/HalfFifty_BE/translation/domain/DTO/TranslationStatus.java

@@ -0,0 +1,7 @@
+package HalfFifty.HalfFifty_BE.translation.domain.DTO;
+
+public enum TranslationStatus {
+    SUCCESS,        // 확정된 번역 결과
+    PROCESSING,     // AI 성공했지만 버퍼링 중
+    FAILED          // AI 실패 또는 오류
+}

HalfFifty_BE/src/main/java/HalfFifty/HalfFifty_BE/translation/domain/DTO/TranslationStatusResponse.java

@@ -0,0 +1,12 @@
+package HalfFifty.HalfFifty_BE.translation.domain.DTO;
+
+import lombok.Builder;
+import lombok.Data;
+
+@Data
+@Builder
+public class TranslationStatusResponse {
+    private String status;
+    private String message;
+    private ResponseTranslationGetDTO data;
+}

HalfFifty_BE/src/main/java/HalfFifty/HalfFifty_BE/translation/service/TranslationService.java

@@ -2,38 +2,79 @@
 
 import HalfFifty.HalfFifty_BE.translation.bean.DeleteTranslationBean;
 import HalfFifty.HalfFifty_BE.translation.bean.FlaskSignLanguageBean;
+import HalfFifty.HalfFifty_BE.translation.bean.FrameBufferBean;
 import HalfFifty.HalfFifty_BE.translation.bean.SaveTranslationBean;
-import HalfFifty.HalfFifty_BE.translation.domain.DTO.RequestSignLanguageDTO;
-import HalfFifty.HalfFifty_BE.translation.domain.DTO.RequestTranslationDeleteDTO;
-import HalfFifty.HalfFifty_BE.translation.domain.DTO.ResponseTranslationGetDTO;
+import HalfFifty.HalfFifty_BE.translation.domain.DTO.*;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
 
 import java.util.Map;
+import java.util.UUID;
 
 
 @Service
 public class TranslationService {
-    SaveTranslationBean saveTranslationBean;
-    FlaskSignLanguageBean flaskSignLanguageBean;
-    DeleteTranslationBean deleteTranslationBean;
+    private final SaveTranslationBean saveTranslationBean;
+    private final FlaskSignLanguageBean flaskSignLanguageBean;
+    private final DeleteTranslationBean deleteTranslationBean;
+    private final FrameBufferBean frameBufferBean;
 
     @Autowired
-    public TranslationService(SaveTranslationBean saveTranslationBean, FlaskSignLanguageBean flaskSignLanguageBean, DeleteTranslationBean deleteTranslationBean) {
+    public TranslationService(SaveTranslationBean saveTranslationBean,
+                              FlaskSignLanguageBean flaskSignLanguageBean,
+                              DeleteTranslationBean deleteTranslationBean,
+                              FrameBufferBean frameBufferBean) {
         this.saveTranslationBean = saveTranslationBean;
         this.flaskSignLanguageBean = flaskSignLanguageBean;
         this.deleteTranslationBean = deleteTranslationBean;
+        this.frameBufferBean = frameBufferBean;
     }
 
-    public ResponseTranslationGetDTO signLanguageTranslation(RequestSignLanguageDTO requestSignLanguageDTO) {
-        Map<String, Object> aiResponse = flaskSignLanguageBean.exec(requestSignLanguageDTO);
+    public TranslationStatusResponse getTranslationStatus(RequestSignLanguageDTO requestSignLanguageDTO) {
+        try {
+            Map<String, Object> aiResponse = flaskSignLanguageBean.exec(requestSignLanguageDTO);
 
-        if (aiResponse != null && Boolean.TRUE.equals(aiResponse.get("success"))) {
-            String translatedWord = (String) aiResponse.get("predicted_label");
-            Double probability = (Double) aiResponse.get("confidence");
-            return saveTranslationBean.exec(requestSignLanguageDTO.getUserId(), translatedWord, probability);
-        } else {
-            return null;
+            if (aiResponse != null && Boolean.TRUE.equals(aiResponse.get("success"))) {
+                String predictedWord = (String) aiResponse.get("predicted_label");
+                Double confidence = (Double) aiResponse.get("confidence");
+
+                FrameBufferResult bufferResult = frameBufferBean.addFrame(
+                        requestSignLanguageDTO.getUserId(),
+                        predictedWord
+                );
+
+                if (bufferResult.isConfirmed()) {
+                    ResponseTranslationGetDTO result = saveTranslationBean.exec(
+                            requestSignLanguageDTO.getUserId(),
+                            bufferResult.getConfirmedWord(),
+                            confidence
+                    );
+                    return TranslationStatusResponse.builder()
+                            .status("success")
+                            .message("수화 번역 성공")
+                            .data(result)
+                            .build();
+                } else {
+                    return TranslationStatusResponse.builder()
+                            .status("processing")
+                            .message("수화 인식 중... (" + bufferResult.getCurrentBufferSize() + "/5)")
+                            .data(null)
+                            .build();
+                }
+            } else {
+                return TranslationStatusResponse.builder()
+                        .status("failed")
+                        .message("수화 인식 실패")
+                        .data(null)
+                        .build();
+            }
+
+        } catch (Exception e) {
+            return TranslationStatusResponse.builder()
+                    .status("failed")
+                    .message("서버 오류: " + e.getMessage())
+                    .data(null)
+                    .build();
         }
     }