From ca9885c5dcdd074e7ba307e7d6867516c356eb8e Mon Sep 17 00:00:00 2001
From: caozehui <2427765068@qq.com>
Date: Thu, 9 Jul 2026 16:35:32 +0800
Subject: [PATCH] =?UTF-8?q?=E8=A2=AB=E6=A3=80=E8=AE=BE=E5=A4=87=E4=B8=8A?=
 =?UTF-8?q?=E4=BC=A0=E5=9B=BE=E7=89=87=E5=8A=9F=E8=83=BD?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../device/controller/PqDevController.java    |  17 +-
 .../device/mapper/mapping/PqDevMapper.xml     |  41 +++-
 .../gather/device/pojo/param/PqDevParam.java  |   4 +
 .../com/njcn/gather/device/pojo/po/PqDev.java |   4 +
 .../njcn/gather/device/pojo/vo/PqDevVO.java   |   6 +
 .../gather/device/service/IPqDevService.java  |   8 +
 .../device/service/impl/PqDevServiceImpl.java |  65 ++++++-
 .../gather/device/util/PqDevImageSupport.java | 181 ++++++++++++++++++
 .../device/util/PqDevImageSupportTest.java    |  55 ++++++
 9 files changed, 372 insertions(+), 9 deletions(-)
 create mode 100644 detection/src/main/java/com/njcn/gather/device/util/PqDevImageSupport.java
 create mode 100644 detection/src/test/java/com/njcn/gather/device/util/PqDevImageSupportTest.java

diff --git a/detection/src/main/java/com/njcn/gather/device/controller/PqDevController.java b/detection/src/main/java/com/njcn/gather/device/controller/PqDevController.java
index a6d673eb..f51ddd54 100644
--- a/detection/src/main/java/com/njcn/gather/device/controller/PqDevController.java
+++ b/detection/src/main/java/com/njcn/gather/device/controller/PqDevController.java
@@ -23,6 +23,7 @@ import io.swagger.annotations.ApiImplicitParams;
 import io.swagger.annotations.ApiOperation;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
+import org.springframework.http.MediaType;
 import org.springframework.validation.annotation.Validated;
 import org.springframework.web.bind.annotation.*;
 import org.springframework.web.multipart.MultipartFile;
@@ -69,10 +70,10 @@ public class PqDevController extends BaseController {
     }
 
     @OperateInfo(operateType = OperateType.ADD)
-    @PostMapping("/add")
+    @PostMapping(value = "/add", consumes = MediaType.MULTIPART_FORM_DATA_VALUE)
     @ApiOperation("新增被检设备")
     @ApiImplicitParam(name = "pqDevParam", value = "被检设备", required = true)
-    public HttpResult<Boolean> add(@RequestBody @Validated PqDevParam pqDevParam) {
+    public HttpResult<Boolean> add(@ModelAttribute @Validated PqDevParam pqDevParam) {
         String methodDescribe = getMethodDescribe("add");
         LogUtil.njcnDebug(log, "{}，新增数据为：{}", methodDescribe, pqDevParam);
         boolean result = pqDevService.addPqDev(pqDevParam);
@@ -84,10 +85,10 @@ public class PqDevController extends BaseController {
     }
 
     @OperateInfo(operateType = OperateType.UPDATE)
-    @PostMapping("/update")
+    @PostMapping(value = "/update", consumes = MediaType.MULTIPART_FORM_DATA_VALUE)
     @ApiOperation("修改被检设备")
     @ApiImplicitParam(name = "updateParam", value = "被检设备", required = true)
-    public HttpResult<Boolean> update(@RequestBody @Validated PqDevParam.UpdateParam updateParam) {
+    public HttpResult<Boolean> update(@ModelAttribute @Validated PqDevParam.UpdateParam updateParam) {
         String methodDescribe = getMethodDescribe("update");
         LogUtil.njcnDebug(log, "{}，修改数据为：{}", methodDescribe, updateParam);
         boolean result = pqDevService.updatePqDev(updateParam);
@@ -98,6 +99,14 @@ public class PqDevController extends BaseController {
         }
     }
 
+    @OperateInfo(info = LogEnum.BUSINESS_COMMON, operateType = OperateType.DOWNLOAD)
+    @GetMapping("/image/download")
+    @ApiOperation("下载设备图片")
+    @ApiImplicitParam(name = "id", value = "被检设备id", required = true)
+    public void downloadImage(@RequestParam("id") String id, HttpServletResponse response) {
+        pqDevService.downloadImage(id, response);
+    }
+
     @OperateInfo(operateType = OperateType.DELETE)
     @PostMapping("/delete")
     @ApiOperation("删除被检设备")
diff --git a/detection/src/main/java/com/njcn/gather/device/mapper/mapping/PqDevMapper.xml b/detection/src/main/java/com/njcn/gather/device/mapper/mapping/PqDevMapper.xml
index cf3e12ed..bee3f825 100644
--- a/detection/src/main/java/com/njcn/gather/device/mapper/mapping/PqDevMapper.xml
+++ b/detection/src/main/java/com/njcn/gather/device/mapper/mapping/PqDevMapper.xml
@@ -86,8 +86,45 @@
         WHERE id = #{planId}
     </select>
 
+    <sql id="DevColumnsNoImage">
+        dev.Id,
+        dev.Name,
+        dev.Pattern,
+        dev.Dev_Type,
+        dev.Manufacturer,
+        dev.Create_Date,
+        dev.Create_Id,
+        dev.Hardware_Version,
+        dev.Software_Version,
+        dev.Protocol,
+        dev.IP,
+        dev.Port,
+        dev.Encryption_Flag,
+        dev.Series,
+        dev.Dev_Key,
+        dev.Sample_Id,
+        dev.Arrived_Date,
+        dev.City_Name,
+        dev.Gd_Name,
+        dev.Sub_Name,
+        dev.Report_Path,
+        dev.Plan_Id,
+        dev.Factor_Flag,
+        dev.Preinvestment_Plan,
+        dev.Delegate,
+        dev.Inspect_Channel,
+        dev.Inspect_Date,
+        dev.Harm_Sys_Id,
+        dev.Import_Flag,
+        dev.State,
+        dev.Create_By,
+        dev.Create_Time,
+        dev.Update_By,
+        dev.Update_Time
+    </sql>
+
     <select id="selectByQueryParam" resultType="com.njcn.gather.device.pojo.vo.PqDevVO">
-        SELECT dev.*,dev_sub.* FROM pq_dev dev
+        SELECT <include refid="DevColumnsNoImage"/>, dev_sub.* FROM pq_dev dev
         left JOIN pq_dev_sub dev_sub ON dev.Id = dev_sub.Dev_Id
         <where>
             dev.state = 1
@@ -124,7 +161,7 @@
     </select>
 
     <select id="listByDevIds" resultType="com.njcn.gather.device.pojo.vo.PqDevVO">
-        SELECT dev.*, dev_sub.*
+        SELECT <include refid="DevColumnsNoImage"/>, dev_sub.*
         FROM pq_dev dev
         left JOIN pq_dev_sub dev_sub ON dev.Id = dev_sub.Dev_Id
         WHERE dev.state = 1
diff --git a/detection/src/main/java/com/njcn/gather/device/pojo/param/PqDevParam.java b/detection/src/main/java/com/njcn/gather/device/pojo/param/PqDevParam.java
index f555d487..3ca2bf22 100644
--- a/detection/src/main/java/com/njcn/gather/device/pojo/param/PqDevParam.java
+++ b/detection/src/main/java/com/njcn/gather/device/pojo/param/PqDevParam.java
@@ -9,6 +9,7 @@ import io.swagger.annotations.ApiModelProperty;
 import lombok.Data;
 import lombok.EqualsAndHashCode;
 import org.hibernate.validator.constraints.Range;
+import org.springframework.web.multipart.MultipartFile;
 
 import javax.validation.Valid;
 import javax.validation.constraints.*;
@@ -136,6 +137,9 @@ public class PqDevParam {
     @ApiModelProperty("是否为导入设备")
     private Integer importFlag;
 
+    @ApiModelProperty("设备图片")
+    private MultipartFile image;
+
     /**
      * 更新操作实体
      */
diff --git a/detection/src/main/java/com/njcn/gather/device/pojo/po/PqDev.java b/detection/src/main/java/com/njcn/gather/device/pojo/po/PqDev.java
index a2a7f21a..0e7d156f 100644
--- a/detection/src/main/java/com/njcn/gather/device/pojo/po/PqDev.java
+++ b/detection/src/main/java/com/njcn/gather/device/pojo/po/PqDev.java
@@ -3,6 +3,7 @@ package com.njcn.gather.device.pojo.po;
 import com.baomidou.mybatisplus.annotation.FieldFill;
 import com.baomidou.mybatisplus.annotation.TableField;
 import com.baomidou.mybatisplus.annotation.TableName;
+import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.annotation.JsonFormat;
 import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
 import com.fasterxml.jackson.databind.annotation.JsonSerialize;
@@ -184,6 +185,9 @@ public class PqDev extends BaseEntity implements Serializable {
      */
     private Integer importFlag;
 
+    @JsonIgnore
+    private byte[] image;
+
     /**
      * 状态：0-删除 1-正常
      */
diff --git a/detection/src/main/java/com/njcn/gather/device/pojo/vo/PqDevVO.java b/detection/src/main/java/com/njcn/gather/device/pojo/vo/PqDevVO.java
index 3ceb374e..b4d07d29 100644
--- a/detection/src/main/java/com/njcn/gather/device/pojo/vo/PqDevVO.java
+++ b/detection/src/main/java/com/njcn/gather/device/pojo/vo/PqDevVO.java
@@ -122,4 +122,10 @@ public class PqDevVO extends PqDev {
      * 检测点结果
      */
     private List<Integer> monitorResults;
+
+    private Boolean hasImage;
+
+    private String imageBase64;
+
+    private String imageContentType;
 }
diff --git a/detection/src/main/java/com/njcn/gather/device/service/IPqDevService.java b/detection/src/main/java/com/njcn/gather/device/service/IPqDevService.java
index d39f245c..c35c092b 100644
--- a/detection/src/main/java/com/njcn/gather/device/service/IPqDevService.java
+++ b/detection/src/main/java/com/njcn/gather/device/service/IPqDevService.java
@@ -96,6 +96,14 @@ public interface IPqDevService extends IService<PqDev> {
      */
     PqDevVO getPqDevById(String id);
 
+    /**
+     * 下载设备图片
+     *
+     * @param id 设备id
+     * @param response 响应
+     */
+    void downloadImage(String id, HttpServletResponse response);
+
     /**
      * 获取装置信息和装置下监测点信息
      *
diff --git a/detection/src/main/java/com/njcn/gather/device/service/impl/PqDevServiceImpl.java b/detection/src/main/java/com/njcn/gather/device/service/impl/PqDevServiceImpl.java
index 8d0eb91c..5d146644 100644
--- a/detection/src/main/java/com/njcn/gather/device/service/impl/PqDevServiceImpl.java
+++ b/detection/src/main/java/com/njcn/gather/device/service/impl/PqDevServiceImpl.java
@@ -5,6 +5,7 @@ import cn.afterturn.easypoi.excel.entity.ExportParams;
 import cn.afterturn.easypoi.excel.entity.ImportParams;
 import cn.afterturn.easypoi.excel.entity.result.ExcelImportResult;
 import cn.hutool.core.bean.BeanUtil;
+import cn.hutool.core.bean.copier.CopyOptions;
 import cn.hutool.core.collection.CollUtil;
 import cn.hutool.core.collection.CollectionUtil;
 import cn.hutool.core.util.ObjectUtil;
@@ -37,6 +38,7 @@ import com.njcn.gather.device.pojo.po.PqDevSub;
 import com.njcn.gather.device.pojo.vo.*;
 import com.njcn.gather.device.service.IPqDevService;
 import com.njcn.gather.device.service.IPqDevSubService;
+import com.njcn.gather.device.util.PqDevImageSupport;
 import com.njcn.gather.monitor.pojo.po.PqMonitor;
 import com.njcn.gather.monitor.pojo.vo.PqMonitorExcel;
 import com.njcn.gather.monitor.service.IPqMonitorService;
@@ -71,6 +73,7 @@ import org.springframework.transaction.annotation.Transactional;
 import org.springframework.web.multipart.MultipartFile;
 
 import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
 import java.time.LocalDateTime;
 import java.util.*;
 import java.util.regex.Pattern;
@@ -138,7 +141,8 @@ public class PqDevServiceImpl extends ServiceImpl<PqDevMapper, PqDev> implements
         this.checkRepeat(pqDevParam, false);
 
         PqDev pqDev = new PqDev();
-        BeanUtil.copyProperties(pqDevParam, pqDev);
+        BeanUtil.copyProperties(pqDevParam, pqDev, CopyOptions.create().setIgnoreProperties("image"));
+        fillImage(pqDev, pqDevParam);
         String currrentScene = sysTestConfigService.getCurrrentScene();
         this.checkParams(pqDev, currrentScene);
 
@@ -169,6 +173,19 @@ public class PqDevServiceImpl extends ServiceImpl<PqDevMapper, PqDev> implements
         return this.save(pqDev);
     }
 
+    private void fillImage(PqDev pqDev, PqDevParam pqDevParam) {
+        try {
+            byte[] image = PqDevImageSupport.processUpload(pqDevParam.getImage());
+            if (image != null) {
+                pqDev.setImage(image);
+            }
+        } catch (IllegalArgumentException e) {
+            throw new BusinessException(CommonResponseEnum.FAIL, e.getMessage());
+        } catch (IOException e) {
+            throw new BusinessException(CommonResponseEnum.FAIL, "图片处理失败");
+        }
+    }
+
     /**
      * 校验参数
      *
@@ -211,7 +228,8 @@ public class PqDevServiceImpl extends ServiceImpl<PqDevMapper, PqDev> implements
         this.checkRepeat(updateParam, true);
 
         PqDev pqDev = new PqDev();
-        BeanUtil.copyProperties(updateParam, pqDev);
+        BeanUtil.copyProperties(updateParam, pqDev, CopyOptions.create().setIgnoreProperties("image"));
+        fillImage(pqDev, updateParam);
         String currrentScene = sysTestConfigService.getCurrrentScene();
         this.checkParams(pqDev, currrentScene);
 
@@ -278,6 +296,8 @@ public class PqDevServiceImpl extends ServiceImpl<PqDevMapper, PqDev> implements
     @Override
     public List<Map<String, Object>> listUnbound(String pattern) {
         List<PqDev> pqDevList = this.lambdaQuery()
+                .select(PqDev::getId, PqDev::getName, PqDev::getDevType, PqDev::getManufacturer,
+                        PqDev::getCityName, PqDev::getGdName, PqDev::getSubName)
                 .eq(PqDev::getPattern, pattern)
                 .eq(PqDev::getState, DataStateEnum.ENABLE.getCode())
                 .isNull(PqDev::getPlanId)
@@ -392,6 +412,10 @@ public class PqDevServiceImpl extends ServiceImpl<PqDevMapper, PqDev> implements
     @Override
     public PqDevVO getPqDevById(String id) {
         PqDevVO pqDevVO = this.baseMapper.selectByDevId(id);
+        if (ObjectUtil.isNull(pqDevVO)) {
+            return null;
+        }
+        setImageEchoFields(pqDevVO);
         if (StrUtil.isNotBlank(pqDevVO.getSeries())) {
             pqDevVO.setSeries(EncryptionUtil.decoderString(1, pqDevVO.getSeries()));
         }
@@ -420,6 +444,37 @@ public class PqDevServiceImpl extends ServiceImpl<PqDevMapper, PqDev> implements
         return pqDevVO;
     }
 
+    @Override
+    public void downloadImage(String id, HttpServletResponse response) {
+        PqDev pqDev = this.getById(id);
+        if (ObjectUtil.isNull(pqDev) || pqDev.getImage() == null || pqDev.getImage().length == 0) {
+            throw new BusinessException(CommonResponseEnum.FAIL, "设备图片不存在");
+        }
+        String contentType = PqDevImageSupport.detectContentType(pqDev.getImage());
+        String filename = "device-image-" + id + "." + PqDevImageSupport.getExtension(contentType);
+        response.setContentType(contentType);
+        response.setContentLength(pqDev.getImage().length);
+        response.setHeader("Content-Disposition", "attachment; filename=\"" + filename + "\"");
+        try {
+            response.getOutputStream().write(pqDev.getImage());
+            response.flushBuffer();
+        } catch (IOException e) {
+            throw new BusinessException(CommonResponseEnum.FAIL, "设备图片下载失败");
+        }
+    }
+
+    private void setImageEchoFields(PqDevVO pqDevVO) {
+        try {
+            PqDevImageSupport.ImageEchoPayload payload = PqDevImageSupport.buildEchoPayload(pqDevVO.getImage());
+            pqDevVO.setHasImage(payload.isHasImage());
+            pqDevVO.setImageBase64(payload.getImageBase64());
+            pqDevVO.setImageContentType(payload.getImageContentType());
+            pqDevVO.setImage(null);
+        } catch (IllegalArgumentException e) {
+            throw new BusinessException(CommonResponseEnum.FAIL, e.getMessage());
+        }
+    }
+
 
     /**
      * 获取查询条件wrapper
@@ -429,6 +484,7 @@ public class PqDevServiceImpl extends ServiceImpl<PqDevMapper, PqDev> implements
      */
     private Wrapper getQueryWrapper(PqDevParam.QueryParam queryParam) {
         QueryWrapper<PqDev> queryWrapper = new QueryWrapper<>();
+        queryWrapper.select("pq_dev.Id");
         if (ObjectUtil.isNotNull(queryParam)) {
             queryWrapper
                     .like(StrUtil.isNotBlank(queryParam.getName()), "pq_dev.name", queryParam.getName())
@@ -1659,7 +1715,10 @@ public class PqDevServiceImpl extends ServiceImpl<PqDevMapper, PqDev> implements
 
     @Override
     public Map<String, List<String>> listSelectOptions(String pattern) {
-        List<PqDev> pqDevList = this.lambdaQuery().eq(PqDev::getPattern, pattern)
+        List<PqDev> pqDevList = this.lambdaQuery()
+                .select(PqDev::getCityName, PqDev::getGdName, PqDev::getSubName,
+                        PqDev::getHardwareVersion, PqDev::getSoftwareVersion)
+                .eq(PqDev::getPattern, pattern)
                 .eq(PqDev::getState, DataStateEnum.ENABLE.getCode())
                 .list();
         String[] devKeyArray = new String[]{"cityName", "gdName", "subName", "hardwareVersion", "softwareVersion"};
diff --git a/detection/src/main/java/com/njcn/gather/device/util/PqDevImageSupport.java b/detection/src/main/java/com/njcn/gather/device/util/PqDevImageSupport.java
new file mode 100644
index 00000000..aa29074e
--- /dev/null
+++ b/detection/src/main/java/com/njcn/gather/device/util/PqDevImageSupport.java
@@ -0,0 +1,181 @@
+package com.njcn.gather.device.util;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import org.springframework.web.multipart.MultipartFile;
+
+import javax.imageio.IIOImage;
+import javax.imageio.ImageIO;
+import javax.imageio.ImageWriteParam;
+import javax.imageio.ImageWriter;
+import javax.imageio.stream.ImageOutputStream;
+import java.awt.Graphics2D;
+import java.awt.RenderingHints;
+import java.awt.image.BufferedImage;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Base64;
+import java.util.Iterator;
+import java.util.Locale;
+
+public final class PqDevImageSupport {
+
+    private static final long MAX_FILE_SIZE = 10L * 1024L * 1024L;
+    private static final int MAX_EDGE = 1600;
+    private static final float JPEG_QUALITY = 0.82f;
+
+    private PqDevImageSupport() {
+    }
+
+    public static ImageEchoPayload buildEchoPayload(byte[] imageBytes) {
+        if (imageBytes == null || imageBytes.length == 0) {
+            return new ImageEchoPayload(false, null, null);
+        }
+        return new ImageEchoPayload(true, Base64.getEncoder().encodeToString(imageBytes), detectContentType(imageBytes));
+    }
+
+    public static String detectContentType(byte[] imageBytes) {
+        if (imageBytes == null || imageBytes.length < 4) {
+            throw new IllegalArgumentException("图片内容无效");
+        }
+        if (isPng(imageBytes)) {
+            return "image/png";
+        }
+        if (isJpeg(imageBytes)) {
+            return "image/jpeg";
+        }
+        throw new IllegalArgumentException("仅支持 JPG、PNG 图片");
+    }
+
+    public static byte[] processUpload(MultipartFile image) throws IOException {
+        if (image == null || image.isEmpty()) {
+            return null;
+        }
+        if (image.getSize() > MAX_FILE_SIZE) {
+            throw new IllegalArgumentException("图片大小不能超过 10MB");
+        }
+
+        String normalizedName = normalize(image.getOriginalFilename());
+        String normalizedContentType = normalize(image.getContentType());
+        boolean allowedType = normalizedContentType.equals("image/jpeg")
+                || normalizedContentType.equals("image/png")
+                || normalizedName.endsWith(".jpg")
+                || normalizedName.endsWith(".jpeg")
+                || normalizedName.endsWith(".png");
+        if (!allowedType) {
+            throw new IllegalArgumentException("仅支持 JPG、PNG 图片");
+        }
+
+        byte[] originalBytes = image.getBytes();
+        String contentType = detectContentType(originalBytes);
+        BufferedImage source;
+        try (InputStream inputStream = image.getInputStream()) {
+            source = ImageIO.read(inputStream);
+        }
+        if (source == null) {
+            throw new IllegalArgumentException("图片内容无效");
+        }
+
+        BufferedImage target = scaleIfNeeded(source);
+        if ("image/png".equals(contentType)) {
+            return writePng(target);
+        }
+        return writeJpeg(target);
+    }
+
+    public static String getExtension(String contentType) {
+        return "image/png".equals(contentType) ? "png" : "jpg";
+    }
+
+    private static BufferedImage scaleIfNeeded(BufferedImage source) {
+        int width = source.getWidth();
+        int height = source.getHeight();
+        int max = Math.max(width, height);
+        if (max <= MAX_EDGE) {
+            return source;
+        }
+
+        double scale = (double) MAX_EDGE / max;
+        int targetWidth = Math.max(1, (int) Math.round(width * scale));
+        int targetHeight = Math.max(1, (int) Math.round(height * scale));
+        int type = source.getType() == BufferedImage.TYPE_CUSTOM ? BufferedImage.TYPE_INT_ARGB : source.getType();
+        BufferedImage target = new BufferedImage(targetWidth, targetHeight, type);
+        Graphics2D graphics = target.createGraphics();
+        try {
+            graphics.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
+            graphics.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
+            graphics.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
+            graphics.drawImage(source, 0, 0, targetWidth, targetHeight, null);
+        } finally {
+            graphics.dispose();
+        }
+        return target;
+    }
+
+    private static byte[] writePng(BufferedImage image) throws IOException {
+        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+        ImageIO.write(image, "png", outputStream);
+        return outputStream.toByteArray();
+    }
+
+    private static byte[] writeJpeg(BufferedImage image) throws IOException {
+        BufferedImage rgbImage = new BufferedImage(image.getWidth(), image.getHeight(), BufferedImage.TYPE_INT_RGB);
+        Graphics2D graphics = rgbImage.createGraphics();
+        try {
+            graphics.drawImage(image, 0, 0, null);
+        } finally {
+            graphics.dispose();
+        }
+
+        Iterator<ImageWriter> writers = ImageIO.getImageWritersByFormatName("jpg");
+        if (!writers.hasNext()) {
+            throw new IOException("未找到 JPG 图片编码器");
+        }
+        ImageWriter writer = writers.next();
+        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+        try (ImageOutputStream imageOutputStream = ImageIO.createImageOutputStream(outputStream)) {
+            writer.setOutput(imageOutputStream);
+            ImageWriteParam writeParam = writer.getDefaultWriteParam();
+            if (writeParam.canWriteCompressed()) {
+                writeParam.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);
+                writeParam.setCompressionQuality(JPEG_QUALITY);
+            }
+            writer.write(null, new IIOImage(rgbImage, null, null), writeParam);
+        } finally {
+            writer.dispose();
+        }
+        return outputStream.toByteArray();
+    }
+
+    private static boolean isPng(byte[] imageBytes) {
+        return imageBytes.length >= 8
+                && (imageBytes[0] & 0xFF) == 0x89
+                && imageBytes[1] == 0x50
+                && imageBytes[2] == 0x4E
+                && imageBytes[3] == 0x47
+                && imageBytes[4] == 0x0D
+                && imageBytes[5] == 0x0A
+                && imageBytes[6] == 0x1A
+                && imageBytes[7] == 0x0A;
+    }
+
+    private static boolean isJpeg(byte[] imageBytes) {
+        return imageBytes.length >= 3
+                && (imageBytes[0] & 0xFF) == 0xFF
+                && (imageBytes[1] & 0xFF) == 0xD8
+                && (imageBytes[2] & 0xFF) == 0xFF;
+    }
+
+    private static String normalize(String value) {
+        return value == null ? "" : value.toLowerCase(Locale.ROOT);
+    }
+
+    @Data
+    @AllArgsConstructor
+    public static class ImageEchoPayload {
+        private boolean hasImage;
+        private String imageBase64;
+        private String imageContentType;
+    }
+}
diff --git a/detection/src/test/java/com/njcn/gather/device/util/PqDevImageSupportTest.java b/detection/src/test/java/com/njcn/gather/device/util/PqDevImageSupportTest.java
new file mode 100644
index 00000000..bc3cc366
--- /dev/null
+++ b/detection/src/test/java/com/njcn/gather/device/util/PqDevImageSupportTest.java
@@ -0,0 +1,55 @@
+package com.njcn.gather.device.util;
+
+import org.junit.Test;
+
+import javax.imageio.ImageIO;
+import java.awt.Color;
+import java.awt.image.BufferedImage;
+import java.io.ByteArrayOutputStream;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+
+public class PqDevImageSupportTest {
+
+    @Test
+    public void buildEchoPayloadReturnsEmptyFieldsWhenImageMissing() {
+        PqDevImageSupport.ImageEchoPayload payload = PqDevImageSupport.buildEchoPayload(null);
+
+        assertFalse(payload.isHasImage());
+        assertNull(payload.getImageBase64());
+        assertNull(payload.getImageContentType());
+    }
+
+    @Test
+    public void buildEchoPayloadDetectsPngAndCreatesBase64() throws Exception {
+        byte[] imageBytes = createImageBytes("png");
+
+        PqDevImageSupport.ImageEchoPayload payload = PqDevImageSupport.buildEchoPayload(imageBytes);
+
+        assertTrue(payload.isHasImage());
+        assertEquals("image/png", payload.getImageContentType());
+        assertNotNull(payload.getImageBase64());
+        assertFalse(payload.getImageBase64().isEmpty());
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void detectContentTypeRejectsInvalidImageBytes() {
+        PqDevImageSupport.detectContentType(new byte[]{1, 2, 3, 4});
+    }
+
+    private byte[] createImageBytes(String format) throws Exception {
+        BufferedImage image = new BufferedImage(2, 2, BufferedImage.TYPE_INT_RGB);
+        image.setRGB(0, 0, Color.RED.getRGB());
+        image.setRGB(1, 0, Color.GREEN.getRGB());
+        image.setRGB(0, 1, Color.BLUE.getRGB());
+        image.setRGB(1, 1, Color.WHITE.getRGB());
+
+        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+        ImageIO.write(image, format, outputStream);
+        return outputStream.toByteArray();
+    }
+}