diff --git a/frontend/app/web-gold/src/components/VideoPreviewModal.vue b/frontend/app/web-gold/src/components/VideoPreviewModal.vue
new file mode 100644
index 0000000000..177468048d
--- /dev/null
+++ b/frontend/app/web-gold/src/components/VideoPreviewModal.vue
@@ -0,0 +1,115 @@
+<template>
+  <a-modal
+    v-model:open="visible"
+    :title="title"
+    :footer="null"
+    width="auto"
+    centered
+    @cancel="handleClose"
+    class="video-preview-modal"
+  >
+    <div class="video-container">
+      <video
+        v-if="visible && videoUrl"
+        ref="videoRef"
+        :src="videoUrl"
+        controls
+        autoplay
+        class="preview-video"
+      >
+        您的浏览器不支持视频播放
+      </video>
+    </div>
+  </a-modal>
+</template>
+
+<script setup>
+import { ref, computed } from 'vue'
+
+const props = defineProps({
+  open: {
+    type: Boolean,
+    default: false
+  },
+  videoUrl: {
+    type: String,
+    default: ''
+  },
+  title: {
+    type: String,
+    default: '视频预览'
+  }
+})
+
+const emit = defineEmits(['update:open'])
+
+const videoRef = ref(null)
+
+const visible = computed({
+  get: () => props.open,
+  set: (val) => emit('update:open', val)
+})
+
+const handleClose = () => {
+  // 关闭时暂停视频
+  if (videoRef.value) {
+    videoRef.value.pause()
+  }
+  visible.value = false
+}
+</script>
+
+<style scoped lang="less">
+.video-preview-modal {
+  :deep(.ant-modal-content) {
+    max-width: 90vw;
+    max-height: 90vh;
+    border-radius: 12px;
+    overflow: hidden;
+    display: flex;
+    flex-direction: column;
+  }
+
+  :deep(.ant-modal-header) {
+    padding: 12px 20px;
+    border-bottom: 1px solid var(--color-gray-200);
+    flex-shrink: 0;
+  }
+
+  :deep(.ant-modal-body) {
+    padding: 0;
+    flex: 1;
+    overflow: hidden;
+  }
+}
+
+.video-container {
+  background: #000;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+}
+
+.preview-video {
+  max-width: 800px;
+  max-height: 70vh;
+  width: auto;
+  height: auto;
+  display: block;
+}
+
+// 响应式：小屏幕
+@media (max-width: 768px) {
+  .video-preview-modal {
+    :deep(.ant-modal-content) {
+      max-width: 95vw;
+      max-height: 85vh;
+    }
+  }
+
+  .preview-video {
+    max-width: 100%;
+    max-height: 60vh;
+  }
+}
+</style>
diff --git a/frontend/app/web-gold/src/components/VideoSelector.vue b/frontend/app/web-gold/src/components/VideoSelector.vue
index 984af1e442..795cb23581 100644
--- a/frontend/app/web-gold/src/components/VideoSelector.vue
+++ b/frontend/app/web-gold/src/components/VideoSelector.vue
@@ -62,6 +62,10 @@
               loading="lazy"
             />
             <div class="video-duration">{{ formatDuration(video.duration) }}</div>
+            <!-- hover 播放按钮 -->
+            <div class="video-play-btn" @click.stop="handlePreview(video)">
+              <PlayCircleOutlined />
+            </div>
             <div class="video-selected-mark" v-if="selectedVideoId === video.id">
               <CheckOutlined />
             </div>
@@ -127,6 +131,13 @@
       </div>
     </div>
   </a-modal>
+
+  <!-- 视频预览弹窗 -->
+  <VideoPreviewModal
+    v-model:open="previewVisible"
+    :video-url="previewUrl"
+    :title="previewVideo?.fileName || '视频预览'"
+  />
 </template>
 
 <script setup>
@@ -138,9 +149,11 @@ import {
   VideoCameraOutlined,
   ClockCircleOutlined,
   SearchOutlined,
-  CloseOutlined
+  CloseOutlined,
+  PlayCircleOutlined
 } from '@ant-design/icons-vue'
 import { MaterialService } from '@/api/material'
+import VideoPreviewModal from '@/components/VideoPreviewModal.vue'
 
 const props = defineProps({
   open: {
@@ -169,6 +182,11 @@ const defaultCover = 'data:image/svg+xml;base64,PHN2ZyB3aWR0aD0iMjAwIiBoZWlnaHQ9
 
 const modalTitle = '选择视频'
 
+// 视频预览状态
+const previewVisible = ref(false)
+const previewUrl = ref('')
+const previewVideo = ref(null)
+
 // 获取视频列表
 const fetchVideoList = async () => {
   loading.value = true
@@ -225,6 +243,35 @@ const selectVideo = (video) => {
   selectedVideo.value = video
 }
 
+// 预览视频
+const handlePreview = async (video) => {
+  if (!video.id) {
+    message.warning('视频信息不完整')
+    return
+  }
+
+  // 显示加载提示
+  const hideLoading = message.loading('正在获取视频地址...', 0)
+
+  try {
+    // 调用后端API获取带签名的视频播放URL
+    const res = await MaterialService.getVideoPlayUrl(video.id)
+    hideLoading()
+
+    if (res.code === 0 && res.data) {
+      previewVideo.value = video
+      previewUrl.value = res.data
+      previewVisible.value = true
+    } else {
+      message.error(res.msg || '获取视频地址失败')
+    }
+  } catch (error) {
+    hideLoading()
+    console.error('获取视频播放URL失败:', error)
+    message.error('获取视频地址失败，请重试')
+  }
+}
+
 const handleImageError = (event) => {
   event.target.src = defaultCover
 }
@@ -239,7 +286,7 @@ const formatDuration = (seconds) => {
 const formatFileSize = (bytes) => {
   if (!bytes) return '0 B'
   const units = ['B', 'KB', 'MB', 'GB']
-  const index = Math.floor(Math.log2(bytes) / 10)
+  const index = Math.floor(Math.log(bytes) / Math.log(1024))
   const size = bytes / Math.pow(1024, index)
   return `${size.toFixed(1)} ${units[index]}`
 }
@@ -436,6 +483,27 @@ watch(() => props.open, (isOpen) => {
   font-size: 14px;
 }
 
+/* hover 播放按钮 */
+.video-play-btn {
+  position: absolute;
+  top: 50%;
+  left: 50%;
+  transform: translate(-50%, -50%);
+  opacity: 0;
+  transition: opacity 0.2s;
+  cursor: pointer;
+}
+
+.video-play-btn .anticon {
+  font-size: 40px;
+  color: white;
+  filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.3));
+}
+
+.video-thumbnail:hover .video-play-btn {
+  opacity: 1;
+}
+
 /* 信息区域样式 */
 .video-info {
   padding: 14px;
diff --git a/frontend/app/web-gold/src/views/material/MaterialListNew.vue b/frontend/app/web-gold/src/views/material/MaterialListNew.vue
index 592c3d4caf..53a500856b 100644
--- a/frontend/app/web-gold/src/views/material/MaterialListNew.vue
+++ b/frontend/app/web-gold/src/views/material/MaterialListNew.vue
@@ -164,6 +164,11 @@
                   <div class="material-item__overlay">
                     <span class="material-item__type-tag">{{ getFileTypeText(file.fileName) }}</span>
                   </div>
+                  <!-- hover 播放按钮 -->
+                  <div class="material-item__play-overlay" @click.stop="handlePreview(file)">
+                    <PlayCircleOutlined />
+                    <span v-if="file.duration" class="duration-tag">{{ formatDuration(file.duration) }}</span>
+                  </div>
                 </div>
 
                 <!-- 文件信息 -->
@@ -261,6 +266,13 @@
         </a-form-item>
       </a-form>
     </a-modal>
+
+    <!-- 视频预览弹窗 -->
+    <VideoPreviewModal
+      v-model:open="previewVisible"
+      :video-url="previewUrl"
+      :title="previewTitle"
+    />
   </div>
   </FullWidthLayout>
 </template>
@@ -279,13 +291,15 @@ import {
   VideoCameraOutlined,
   UserOutlined,
   CheckOutlined,
-  CheckSquareOutlined
+  CheckSquareOutlined,
+  PlayCircleOutlined
 } from '@ant-design/icons-vue';
 import { message, Modal } from 'ant-design-vue';
 import MaterialUploadModal from '@/components/material/MaterialUploadModal.vue';
 import MaterialService, { MaterialGroupService } from '@/api/material';
 import FullWidthLayout from '@/layouts/components/FullWidthLayout.vue';
 import { useUserStore } from '@/stores/user';
+import VideoPreviewModal from '@/components/VideoPreviewModal.vue';
 
 // 用户状态（获取存储配额）
 const userStore = useUserStore()
@@ -313,6 +327,11 @@ const createGroupForm = reactive({
 // 文件选择
 const selectedFileIds = ref([])
 
+// 视频预览状态
+const previewVisible = ref(false)
+const previewUrl = ref('')
+const previewTitle = ref('')
+
 // 编辑状态
 const editingFileId = ref(null)
 const editingDisplayName = ref('')
@@ -398,6 +417,22 @@ const handleSaveGroupName = async (group) => {
   }
 }
 
+// 通用的确认删除弹窗
+const showConfirmDelete = (title, content) => {
+  return new Promise((resolve) => {
+    Modal.confirm({
+      title,
+      content,
+      okText: '确认删除',
+      cancelText: '取消',
+      okType: 'danger',
+      centered: true,
+      onOk: () => resolve(true),
+      onCancel: () => resolve(false),
+    })
+  })
+}
+
 const handleDeleteGroup = async (group, event) => {
   event?.stopPropagation?.()
 
@@ -407,39 +442,17 @@ const handleDeleteGroup = async (group, event) => {
     return
   }
 
-  const confirmed = await new Promise((resolve) => {
-    Modal.confirm({
-      title: '删除分组',
-      content: `确定要删除分组「${group.name}」吗？此操作不可恢复。`,
-      okText: '确认删除',
-      cancelText: '取消',
-      okType: 'danger',
-      centered: true,
-      class: 'delete-group-modal',
-      onOk() {
-        resolve(true)
-      },
-      onCancel() {
-        resolve(false)
-      },
-    })
-  })
-
+  const confirmed = await showConfirmDelete('删除分组', `确定要删除分组「${group.name}」吗？此操作不可恢复。`)
   if (!confirmed) return
 
   try {
     loading.value = true
     await MaterialGroupService.deleteGroup(group.id)
 
-    // 移除已删除的分组
-    const index = groupList.value.findIndex(g => g.id === group.id)
-    if (index > -1) {
-      groupList.value.splice(index, 1)
-    }
-
-    // 重新选择分组
+    // 移除已删除的分组并重新选择
+    groupList.value = groupList.value.filter(g => g.id !== group.id)
     if (selectedGroupId.value === group.id) {
-      selectedGroupId.value = groupList.value.length > 0 ? groupList.value[0].id : null
+      selectedGroupId.value = groupList.value[0]?.id ?? null
       await loadFileList()
     }
 
@@ -582,34 +595,16 @@ const handleBatchDelete = async () => {
 
   const count = selectedFileIds.value.length
   const fileIdsToDelete = [...selectedFileIds.value]
-  const confirmed = await new Promise((resolve) => {
-    Modal.confirm({
-      title: '确认删除',
-      content: `确定要删除选中的 ${count} 个文件吗？此操作不可恢复。`,
-      okText: '确认删除',
-      cancelText: '取消',
-      okType: 'danger',
-      centered: true,
-      class: 'batch-delete-modal',
-      onOk() {
-        resolve(true)
-      },
-      onCancel() {
-        resolve(false)
-      },
-    })
-  })
 
+  const confirmed = await showConfirmDelete('确认删除', `确定要删除选中的 ${count} 个文件吗？此操作不可恢复。`)
   if (!confirmed) return
 
   try {
     loading.value = true
     await MaterialService.deleteFiles(fileIdsToDelete)
 
-    // 移除已删除的文件
+    // 移除已删除的文件并更新状态
     fileList.value = fileList.value.filter(file => !fileIdsToDelete.includes(file.id))
-
-    // 更新状态
     totalFileCount.value = Math.max(0, totalFileCount.value - count)
     selectedFileIds.value = []
 
@@ -618,7 +613,7 @@ const handleBatchDelete = async () => {
 
     // 如果删除后当前页没有数据了，则加载上一页
     if (fileList.value.length === 0 && pagination.current > 1) {
-      pagination.current = pagination.current - 1
+      pagination.current--
       await loadFileList()
     }
 
@@ -631,14 +626,12 @@ const handleBatchDelete = async () => {
   }
 }
 
-const formatFileSize = (size) => {
+const formatFileSize = (bytes) => {
+  if (!bytes) return '0 B'
   const units = ['B', 'KB', 'MB', 'GB']
-  let unitIndex = 0
-  while (size >= 1024 && unitIndex < units.length - 1) {
-    size /= 1024
-    unitIndex++
-  }
-  return `${size.toFixed(2)} ${units[unitIndex]}`
+  const index = Math.floor(Math.log(bytes) / Math.log(1024))
+  const size = bytes / Math.pow(1024, index)
+  return `${size.toFixed(1)} ${units[index]}`
 }
 
 const formatDate = (date) => {
@@ -707,6 +700,43 @@ const handleImageError = (e) => {
   e.target.style.display = 'none'
 }
 
+// 视频预览
+const handlePreview = async (file) => {
+  if (!file.id) {
+    message.warning('文件信息不完整')
+    return
+  }
+
+  // 显示加载提示
+  const hideLoading = message.loading('正在获取视频地址...', 0)
+
+  try {
+    // 调用后端API获取带签名的视频播放URL
+    const res = await MaterialService.getVideoPlayUrl(file.id)
+    hideLoading()
+
+    if (res.code === 0 && res.data) {
+      previewUrl.value = res.data
+      previewTitle.value = file.displayName || file.fileName || '视频预览'
+      previewVisible.value = true
+    } else {
+      message.error(res.msg || '获取视频地址失败')
+    }
+  } catch (error) {
+    hideLoading()
+    console.error('获取视频播放URL失败:', error)
+    message.error('获取视频地址失败，请重试')
+  }
+}
+
+// 格式化时长
+const formatDuration = (seconds) => {
+  if (!seconds) return ''
+  const mins = Math.floor(seconds / 60)
+  const secs = Math.floor(seconds % 60)
+  return `${String(mins).padStart(2, '0')}:${String(secs).padStart(2, '0')}`
+}
+
 // 监听分类变化
 watch(activeCategory, () => {
   selectedFileIds.value = []
@@ -1251,6 +1281,37 @@ onMounted(async () => {
     transition: opacity var(--duration-slow) ease;
   }
 
+  &__play-overlay {
+    position: absolute;
+    inset: 0;
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    justify-content: center;
+    gap: var(--space-2);
+    background: rgba(0, 0, 0, 0.4);
+    opacity: 0;
+    transition: opacity var(--duration-base);
+    cursor: pointer;
+
+    .anticon {
+      font-size: 48px;
+      color: white;
+    }
+
+    .duration-tag {
+      padding: 2px 8px;
+      background: rgba(0, 0, 0, 0.6);
+      border-radius: 4px;
+      color: white;
+      font-size: var(--font-size-xs);
+    }
+  }
+
+  &__preview:hover &__play-overlay {
+    opacity: 1;
+  }
+
   &__type-tag {
     font-size: var(--font-size-xs);
     font-weight: 600;
@@ -1358,8 +1419,7 @@ onMounted(async () => {
 // ========================================
 // 弹窗样式
 // ========================================
-:deep(.batch-delete-modal),
-:deep(.delete-group-modal) {
+:deep(.ant-modal-confirm) {
   .ant-modal-content {
     border-radius: var(--radius-lg);
     overflow: hidden;
diff --git a/frontend/app/web-gold/src/views/material/Mix.vue b/frontend/app/web-gold/src/views/material/Mix.vue
index e04ed81878..03f09087c4 100644
--- a/frontend/app/web-gold/src/views/material/Mix.vue
+++ b/frontend/app/web-gold/src/views/material/Mix.vue
@@ -21,6 +21,7 @@
             :min="15"
             :max="30"
             :step="1"
+            :tooltip-visible="false"
             style="width: 100px;"
           />
           <span class="param-value">{{ formData.totalDuration }}s</span>
@@ -35,6 +36,7 @@
             :min="3"
             :max="5"
             :step="1"
+            :tooltip-visible="false"
             style="width: 80px;"
           />
           <span class="param-value">{{ formData.clipDuration }}s</span>
@@ -321,8 +323,8 @@ const showSettings = ref(false)
 const formData = ref({
   title: '',
   produceCount: Number(localStorage.getItem('mix-produce-count')) || 3,
-  totalDuration: 15,
-  clipDuration: 5,
+  totalDuration: Number(localStorage.getItem('mix-total-duration')) || 15,
+  clipDuration: Number(localStorage.getItem('mix-clip-duration')) || 5,
   cropMode: localStorage.getItem('mix-crop-mode') || 'center'
 })
 
@@ -418,6 +420,19 @@ watch(sceneCount, (newCount) => {
   }
 }, { immediate: true })
 
+// 当 clipDuration 变化时，同步更新所有场景的 duration，并保存到本地
+watch(() => formData.value.clipDuration, (newDuration) => {
+  localStorage.setItem('mix-clip-duration', newDuration.toString())
+  dataState.value.scenes.forEach(scene => {
+    scene.duration = newDuration
+  })
+})
+
+// 当 totalDuration 变化时，保存到本地
+watch(() => formData.value.totalDuration, (newDuration) => {
+  localStorage.setItem('mix-total-duration', newDuration.toString())
+})
+
 const onSceneDragEnd = () => {
   dataState.value.scenes.forEach((scene, index) => {
     scene.index = index
diff --git a/frontend/app/web-gold/src/views/system/task-management/digital-human-task/index.vue b/frontend/app/web-gold/src/views/system/task-management/digital-human-task/index.vue
index 923a1ae83a..886ca636be 100644
--- a/frontend/app/web-gold/src/views/system/task-management/digital-human-task/index.vue
+++ b/frontend/app/web-gold/src/views/system/task-management/digital-human-task/index.vue
@@ -96,6 +96,16 @@
             <!-- 操作列 -->
             <template v-else-if="column.key === 'actions'">
               <a-space>
+                <a-button
+                  v-if="isStatus(record.status, 'success')"
+                  type="link"
+                  size="small"
+                  class="action-btn action-btn--primary"
+                  @click="handlePreview(record)"
+                >
+                  <PlayCircleOutlined /> 预览
+                </a-button>
+
                 <a-button
                   v-if="isStatus(record.status, 'success')"
                   type="link"
@@ -122,19 +132,27 @@
         </a-table>
       </a-spin>
     </div>
+
+    <!-- 视频预览弹窗 -->
+    <VideoPreviewModal
+      v-model:open="previewVisible"
+      :video-url="previewUrl"
+      :title="previewTitle"
+    />
   </div>
 </template>
 
 <script setup>
 import { ref, onMounted } from 'vue'
 import { message, Modal } from 'ant-design-vue'
-import { SearchOutlined, DownloadOutlined, DeleteOutlined } from '@ant-design/icons-vue'
-import { getDigitalHumanTaskPage, cancelTask, deleteTask } from '@/api/digitalHuman'
+import { SearchOutlined, DownloadOutlined, DeleteOutlined, PlayCircleOutlined } from '@ant-design/icons-vue'
+import { getDigitalHumanTaskPage, cancelTask, deleteTask, getSignedUrls } from '@/api/digitalHuman'
 import { formatDate } from '@/utils/file'
 import { useTaskList } from '@/views/system/task-management/composables/useTaskList'
 import { useTaskOperations } from '@/views/system/task-management/composables/useTaskOperations'
 import { useTaskPolling } from '@/views/system/task-management/composables/useTaskPolling'
 import TaskStatusTag from '@/views/system/task-management/components/TaskStatusTag.vue'
+import VideoPreviewModal from '@/components/VideoPreviewModal.vue'
 
 // 进度状态映射
 const PROGRESS_STATUS = {
@@ -157,9 +175,43 @@ const rowSelection = {
   onChange: (keys) => { selectedRowKeys.value = keys }
 }
 
+// 视频预览状态
+const previewVisible = ref(false)
+const previewUrl = ref('')
+const previewTitle = ref('')
+
 // 状态判断
 const isStatus = (status, target) => status === target || status === target.toUpperCase()
 
+// 预览视频
+const handlePreview = async (record) => {
+  if (!record.id) {
+    message.warning('任务信息不完整')
+    return
+  }
+
+  // 显示加载提示
+  const hideLoading = message.loading('正在获取视频地址...', 0)
+
+  try {
+    // 调用后端API获取带签名的视频URL
+    const res = await getSignedUrls(record.id)
+    hideLoading()
+
+    if (res.code === 0 && res.data && res.data.length > 0) {
+      previewUrl.value = res.data[0]
+      previewTitle.value = record.taskName || '视频预览'
+      previewVisible.value = true
+    } else {
+      message.error(res.msg || '获取视频地址失败')
+    }
+  } catch (error) {
+    hideLoading()
+    console.error('获取视频播放URL失败:', error)
+    message.error('获取视频地址失败，请重试')
+  }
+}
+
 // 下载视频
 const handleDownload = (record) => {
   if (!record.resultVideoUrl) {
@@ -268,6 +320,7 @@ onMounted(fetchList)
 }
 
 .action-btn {
+  &--primary { color: var(--color-primary-500); &:hover { color: var(--color-primary-600); } }
   &--success { color: var(--color-success-500); &:hover { color: var(--color-success-600); } }
   &--danger { color: var(--color-error-500); &:hover { color: var(--color-error-600); } }
 }
diff --git a/yudao-module-tik/src/main/java/cn/iocoder/yudao/module/tik/file/service/TikUserFileServiceImpl.java b/yudao-module-tik/src/main/java/cn/iocoder/yudao/module/tik/file/service/TikUserFileServiceImpl.java
index c84c35d86f..1c3573004e 100644
--- a/yudao-module-tik/src/main/java/cn/iocoder/yudao/module/tik/file/service/TikUserFileServiceImpl.java
+++ b/yudao-module-tik/src/main/java/cn/iocoder/yudao/module/tik/file/service/TikUserFileServiceImpl.java
@@ -331,70 +331,49 @@ public class TikUserFileServiceImpl implements TikUserFileService {
         log.info("[deleteFiles][用户({})删除文件成功，数量({})]", userId, fileIds.size());
     }
 
-    @Override
-    public String getVideoPlayUrl(Long fileId) {
+    /**
+     * 查询用户文件（校验归属权）
+     */
+    private TikUserFileDO getUserFile(Long fileId) {
         Long userId = SecurityFrameworkUtils.getLoginUserId();
-
-        // 查询文件（根据 fileId 字段查询）
         TikUserFileDO file = userFileMapper.selectOne(new LambdaQueryWrapperX<TikUserFileDO>()
-                .eq(TikUserFileDO::getFileId, fileId)
+                .eq(TikUserFileDO::getId, fileId)
                 .eq(TikUserFileDO::getUserId, userId));
-
         if (file == null) {
             throw exception(FILE_NOT_EXISTS, "文件不存在");
         }
+        return file;
+    }
+
+    @Override
+    public String getVideoPlayUrl(Long fileId) {
+        TikUserFileDO file = getUserFile(fileId);
 
-        // 校验文件URL是否为空
         if (StrUtil.isBlank(file.getFileUrl())) {
             throw exception(FILE_NOT_EXISTS, "文件URL为空");
         }
-
-        // 校验是否为视频文件
-        boolean isVideo = StrUtil.containsIgnoreCase(file.getFileType(), "video");
-        if (!isVideo) {
+        if (!StrUtil.containsIgnoreCase(file.getFileType(), "video")) {
             throw exception(FILE_CATEGORY_INVALID, "文件不是视频类型");
         }
 
-        // 生成预签名URL（24小时有效期）
         return getCachedPresignUrl(file.getFileUrl(), PRESIGN_URL_EXPIRATION_SECONDS);
     }
 
     @Override
     public String getAudioPlayUrl(Long fileId) {
-        Long userId = SecurityFrameworkUtils.getLoginUserId();
+        TikUserFileDO file = getUserFile(fileId);
 
-        // 查询文件（根据 fileId 字段查询）
-        TikUserFileDO file = userFileMapper.selectOne(new LambdaQueryWrapperX<TikUserFileDO>()
-                .eq(TikUserFileDO::getFileId, fileId)
-                .eq(TikUserFileDO::getUserId, userId));
-
-        if (file == null) {
-            throw exception(FILE_NOT_EXISTS, "文件不存在");
-        }
-
-        // 校验是否为音频文件
         if (!StrUtil.containsIgnoreCase(file.getFileType(), "audio")) {
             throw exception(FILE_CATEGORY_INVALID, "文件不是音频类型");
         }
 
-        // 生成预签名URL（1小时有效期）
         return getCachedPresignUrl(file.getFileUrl(), PRESIGN_URL_EXPIRATION_SECONDS);
     }
 
     @Override
     public String getPreviewUrl(Long fileId, String type) {
-        Long userId = SecurityFrameworkUtils.getLoginUserId();
-
-        // 查询文件（根据主键id查询）
-        TikUserFileDO file = userFileMapper.selectById(fileId);
-        if (file == null || !file.getUserId().equals(userId)) {
-            throw exception(FILE_NOT_EXISTS);
-        }
-
-        // 根据类型返回预览URL
+        TikUserFileDO file = getUserFile(fileId);
         String previewUrl = determinePreviewUrl(file, type);
-
-        // 生成预签名URL（1小时有效期）
         return getCachedPresignUrl(previewUrl, PRESIGN_URL_EXPIRATION_SECONDS);
     }
 
@@ -408,14 +387,14 @@ public class TikUserFileServiceImpl implements TikUserFileService {
         }
 
         // 明确指定类型
-        if (StrUtil.equals(type, "cover") && StrUtil.isNotBlank(file.getCoverUrl())) {
+        if ("cover".equals(type) && StrUtil.isNotBlank(file.getCoverUrl())) {
             return file.getCoverUrl();
         }
-        if (StrUtil.equals(type, "thumbnail") && StrUtil.isNotBlank(file.getThumbnailUrl())) {
+        if ("thumbnail".equals(type) && StrUtil.isNotBlank(file.getThumbnailUrl())) {
             return file.getThumbnailUrl();
         }
 
-        // 根据文件类型自动选择
+        // 根据文件类型自动选择：图片优先缩略图，否则原图
         if (FileTypeUtils.isImage(file.getFileType())) {
             return StrUtil.isNotBlank(file.getThumbnailUrl()) ? file.getThumbnailUrl() : file.getFileUrl();
         }