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scripts/cover/modules/__init__.py

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+"""
+modules 包初始化文件
+"""
+
+# 这个文件是必需的，让 Python 将 modules 目录识别为一个包
+# 从而支持相对导入（如 from .utils import ...）

scripts/cover/modules/cover_templates.py

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+# -*- coding: utf-8 -*-
+"""
+封面模板定义文件
+Cover Template Definitions
+"""
+
+from typing import Dict, Any, Tuple
+
+# 封面模板配置
+COVER_TEMPLATES: Dict[str, Dict[str, Any]] = {
+    'professional': {
+        'name': '专业商务风',
+        'description': '金色描边 + 中度虚化 + 人物清晰',
+        'blur_radius': 25,  # 背景模糊半径
+        'outline_color': (255, 215, 0),  # 金色 (R, G, B)
+        'outline_width': 8,  # 描边宽度
+        'brightness': 0.9,  # 亮度调整 (0.0-1.0)
+        'contrast': 1.0,  # 对比度
+        'preview_path': '/assets/templates/professional.jpg'
+    },
+    'vibrant': {
+        'name': '活力青春风',
+        'description': '粉色描边 + 轻度虚化 + 明亮色调',
+        'blur_radius': 20,
+        'outline_color': (255, 105, 180),  # 粉色 (R, G, B)
+        'outline_width': 6,
+        'brightness': 1.1,
+        'contrast': 1.05,
+        'preview_path': '/assets/templates/vibrant.jpg'
+    },
+    'elegant': {
+        'name': '优雅高级风',
+        'description': '银色描边 + 重度虚化 + 柔和光效',
+        'blur_radius': 30,
+        'outline_color': (192, 192, 192),  # 银色 (R, G, B)
+        'outline_width': 10,
+        'brightness': 0.85,
+        'contrast': 0.95,
+        'preview_path': '/assets/templates/elegant.jpg'
+    },
+    'classic': {
+        'name': '经典商务风',
+        'description': '白色描边 + 轻度虚化 + 简洁风格',
+        'blur_radius': 15,
+        'outline_color': (255, 255, 255),  # 白色 (R, G, B)
+        'outline_width': 5,
+        'brightness': 0.95,
+        'contrast': 1.0,
+        'preview_path': '/assets/templates/classic.jpg'
+    },
+    'dramatic': {
+        'name': '戏剧艺术风',
+        'description': '红色描边 + 重度虚化 + 强烈对比',
+        'blur_radius': 35,
+        'outline_color': (220, 20, 60),  # 红色 (R, G, B)
+        'outline_width': 12,
+        'brightness': 0.8,
+        'contrast': 1.2,
+        'preview_path': '/assets/templates/dramatic.jpg'
+    }
+}
+
+def get_template(template_id: str) -> Dict[str, Any]:
+    """
+    获取模板配置
+
+    Args:
+        template_id: 模板ID
+
+    Returns:
+        模板配置字典
+    """
+    return COVER_TEMPLATES.get(template_id, COVER_TEMPLATES['professional'])
+
+def get_all_templates() -> Dict[str, Dict[str, Any]]:
+    """
+    获取所有模板配置
+
+    Returns:
+        所有模板配置字典
+    """
+    return COVER_TEMPLATES.copy()
+
+def get_template_names() -> Dict[str, str]:
+    """
+    获取模板ID和名称映射
+
+    Returns:
+        {template_id: template_name}
+    """
+    return {k: v['name'] for k, v in COVER_TEMPLATES.items()}
+
+def get_template_descriptions() -> Dict[str, str]:
+    """
+    获取模板ID和描述映射
+
+    Returns:
+        {template_id: template_description}
+    """
+    return {k: v['description'] for k, v in COVER_TEMPLATES.items()}
+
+def get_template_preview_paths() -> Dict[str, str]:
+    """
+    获取模板ID和预览图路径映射
+
+    Returns:
+        {template_id: preview_path}
+    """
+    return {k: v['preview_path'] for k, v in COVER_TEMPLATES.items()}
+
+# 模板效果参数范围定义（用于UI验证）
+TEMPLATE_PARAM_RANGES = {
+    'blur_radius': {'min': 0, 'max': 50, 'default': 25},
+    'outline_width': {'min': 0, 'max': 20, 'default': 8},
+    'brightness': {'min': 0.5, 'max': 1.5, 'default': 1.0},
+    'contrast': {'min': 0.5, 'max': 1.5, 'default': 1.0}
+}

scripts/cover/modules/font_manager.py

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+"""
+字体管理模块
+负责查找和管理字体文件，支持预置字体、系统字体、ziti目录字体和Google Fonts
+"""
+import os
+import sys
+import platform
+from pathlib import Path
+from typing import Dict, List, Optional, Tuple
+import json
+
+# 尝试导入loguru，如果不可用则使用print作为替代
+try:
+    from loguru import logger
+except ImportError:
+    # Fallback logger that uses print
+    class logger:
+        @staticmethod
+        def info(msg, *args, **kwargs):
+            print(f"[INFO] {msg}", file=sys.stderr)
+        @staticmethod
+        def warning(msg, *args, **kwargs):
+            print(f"[WARN] {msg}", file=sys.stderr)
+        @staticmethod
+        def error(msg, *args, **kwargs):
+            print(f"[ERROR] {msg}", file=sys.stderr)
+        @staticmethod
+        def debug(msg, *args, **kwargs):
+            print(f"[DEBUG] {msg}", file=sys.stderr)
+
+
+class FontManager:
+    """字体管理器"""
+
+    def __init__(self):
+        # 计算项目根目录（从 python/modules 向上两级）
+        # __file__ 应该是 .../python/modules/font_manager.py
+        current_file = Path(__file__).resolve()
+        python_dir = current_file.parent.parent  # python 目录
+        project_root = python_dir.parent  # 项目根目录
+
+        self.bundled_fonts_dir = Path("fonts/bundled")
+        self.fonts_metadata_file = self.bundled_fonts_dir / "fonts_metadata.json"
+
+        # 🔧 修复ziti字体路径：支持ASAR打包环境
+        # 检查是否在打包环境中运行
+        app_root = os.environ.get('APP_ROOT', None)
+        if app_root:
+            ziti_path_bundle = Path(app_root) / "resources-bundles" / "ziti"
+            if ziti_path_bundle.exists():
+                self.ziti_fonts_dir = ziti_path_bundle
+                print(f"✅ [font_manager] 找到ziti字体目录(bundle): {ziti_path_bundle}")
+            else:
+                ziti_path = Path(app_root) / "extra" / "common" / "fonts" / "ziti"
+                if ziti_path.exists():
+                    self.ziti_fonts_dir = ziti_path
+                    print(f"✅ [font_manager] 找到ziti字体目录: {ziti_path}")
+                else:
+                    ziti_path_fallback1 = Path(app_root) / "app.asar.unpacked" / "ziti"
+                    if ziti_path_fallback1.exists():
+                        self.ziti_fonts_dir = ziti_path_fallback1
+                        print(f"✅ [font_manager] 找到ziti字体目录(回退1): {ziti_path_fallback1}")
+                    else:
+                        ziti_path_fallback2 = Path(app_root) / "ziti"
+                        self.ziti_fonts_dir = ziti_path_fallback2
+                        print(f"⚠️ [font_manager] 使用回退路径: {ziti_path_fallback2} (存在: {ziti_path_fallback2.exists()})")
+        else:
+            self.ziti_fonts_dir = project_root / "ziti"
+            print(f"🔧 [font_manager] 开发环境ziti路径: {self.ziti_fonts_dir}")
+        self._bundled_fonts_cache: Optional[Dict] = None
+        self._system_fonts_cache: Optional[List[Dict]] = None
+        self._ziti_fonts_cache: Optional[List[Dict]] = None  # 新增：ziti字体缓存
+
+        # 诊断日志
+        logger.debug(f"FontManager 初始化: current_file={current_file}, python_dir={python_dir}, project_root={project_root}")
+        logger.debug(f"ziti_fonts_dir={self.ziti_fonts_dir.absolute()}, exists={self.ziti_fonts_dir.exists()}")
+    
+    def get_bundled_fonts(self) -> List[Dict]:
+        """获取预置字体列表"""
+        if self._bundled_fonts_cache is not None:
+            return self._bundled_fonts_cache.get("fonts", [])
+        
+        if not self.fonts_metadata_file.exists():
+            logger.warning(f"字体元数据文件不存在: {self.fonts_metadata_file}")
+            return []
+        
+        try:
+            with open(self.fonts_metadata_file, "r", encoding="utf-8") as f:
+                metadata = json.load(f)
+                self._bundled_fonts_cache = metadata
+                return metadata.get("fonts", [])
+        except Exception as e:
+            logger.error(f"读取字体元数据失败: {e}")
+            return []
+    
+    def scan_ziti_fonts(self) -> List[Dict]:
+        """扫描ziti目录中的字体文件"""
+        if self._ziti_fonts_cache is not None:
+            return self._ziti_fonts_cache
+
+        ziti_fonts = []
+
+        logger.info(f"正在扫描 ziti 目录: {self.ziti_fonts_dir.absolute()}")
+        logger.info(f"  当前工作目录: {os.getcwd()}")
+        logger.info(f"  APP_ROOT环境变量: {os.environ.get('APP_ROOT', 'None')}")
+
+        if not self.ziti_fonts_dir.exists():
+            logger.warning(f"❌ ziti目录不存在: {self.ziti_fonts_dir.absolute()}")
+            logger.warning(f"  请检查路径配置和资源文件是否正确打包")
+            return []
+        else:
+            logger.info(f"✅ ziti目录存在，开始扫描字体文件...")
+        
+        try:
+            # 支持的字体格式
+            font_extensions = ['.ttf', '.otf', '.ttc', '.woff', '.woff2']
+            
+            # 扫描ziti目录中的所有字体文件
+            for font_file in self.ziti_fonts_dir.iterdir():
+                if font_file.is_file() and font_file.suffix.lower() in font_extensions:
+                    # 从文件名提取字体信息
+                    font_name = font_file.stem
+                    
+                    # 尝试解析字体名称和变体
+                    display_name = font_name
+                    family = font_name
+                    weight = 400
+                    
+                    # 检测常见的字体变体
+                    name_lower = font_name.lower()
+                    if 'bold' in name_lower:
+                        weight = 700
+                    elif 'semibold' in name_lower:
+                        weight = 600
+                    elif 'medium' in name_lower:
+                        weight = 500
+                    elif 'light' in name_lower:
+                        weight = 300
+                    elif 'thin' in name_lower:
+                        weight = 100
+                    elif 'black' in name_lower or 'extrabold' in name_lower:
+                        weight = 900
+                    
+                    # 清理family名称（移除变体后缀）
+                    for variant in ['-Bold', '-SemiBold', '-Medium', '-Light', '-Thin', '-Black', '-ExtraBold', '-Regular']:
+                        if family.endswith(variant):
+                            family = family[:-len(variant)]
+                            break
+                    
+                    ziti_fonts.append({
+                        'family': family,
+                        'display_name': display_name,
+                        'path': str(font_file.absolute()),
+                        'source': 'ziti',
+                        'weight': weight,
+                        'category': 'sans-serif',  # 默认分类
+                        'languages': ['zh-CN', 'ja', 'en']  # 假设支持中日英
+                    })
+            
+            logger.info(f"✅ 从ziti目录扫描到 {len(ziti_fonts)} 个字体")
+            if len(ziti_fonts) > 0:
+                logger.debug(f"  扫描到的字体: {', '.join([f['family'] for f in ziti_fonts[:5]])}" +
+                           (f" 等({len(ziti_fonts)}个)" if len(ziti_fonts) > 5 else ""))
+
+        except Exception as e:
+            logger.error(f"❌ 扫描ziti目录字体失败: {e}")
+            import traceback
+            logger.error(f"  追踪: {traceback.format_exc()}")
+        
+        # 去重（按family和weight）
+        seen = set()
+        unique_fonts = []
+        for font in ziti_fonts:
+            key = (font['family'], font.get('weight', 400))
+            if key not in seen:
+                seen.add(key)
+                unique_fonts.append(font)
+        
+        self._ziti_fonts_cache = unique_fonts
+        return unique_fonts
+    
+    def scan_system_fonts(self) -> List[Dict]:
+        """扫描系统已安装的字体"""
+        if self._system_fonts_cache is not None:
+            return self._system_fonts_cache
+        
+        system_fonts = []
+        system = platform.system()
+        
+        try:
+            if system == 'Windows':
+                font_dir = Path("C:/Windows/Fonts")
+                if font_dir.exists():
+                    # 常见Windows字体
+                    common_fonts = {
+                        'simhei.ttf': {'family': 'SimHei', 'display_name': '黑体'},
+                        'simsun.ttc': {'family': 'SimSun', 'display_name': '宋体'},
+                        'msyh.ttc': {'family': 'Microsoft YaHei', 'display_name': '微软雅黑'},
+                        'msyhbd.ttc': {'family': 'Microsoft YaHei', 'display_name': '微软雅黑 Bold', 'weight': 700},
+                        'arial.ttf': {'family': 'Arial', 'display_name': 'Arial'},
+                        'arialbd.ttf': {'family': 'Arial', 'display_name': 'Arial Bold', 'weight': 700},
+                        'times.ttf': {'family': 'Times New Roman', 'display_name': 'Times New Roman'},
+                        'timesbd.ttf': {'family': 'Times New Roman', 'display_name': 'Times New Roman Bold', 'weight': 700},
+                    }
+                    
+                    for font_file, font_info in common_fonts.items():
+                        font_path = font_dir / font_file
+                        if font_path.exists():
+                            system_fonts.append({
+                                'family': font_info['family'],
+                                'display_name': font_info['display_name'],
+                                'path': str(font_path),
+                                'source': 'system',
+                                'weight': font_info.get('weight', 400)
+                            })
+            
+            elif system == 'Darwin':  # macOS
+                font_dirs = [
+                    Path("/System/Library/Fonts"),
+                    Path("/Library/Fonts"),
+                    Path.home() / "Library/Fonts"
+                ]
+                
+                common_fonts = {
+                    'PingFang.ttc': {'family': 'PingFang SC', 'display_name': '苹方'},
+                    'Arial.ttf': {'family': 'Arial', 'display_name': 'Arial'},
+                }
+                
+                for font_dir in font_dirs:
+                    if font_dir.exists():
+                        for font_file, font_info in common_fonts.items():
+                            font_path = font_dir / font_file
+                            if font_path.exists():
+                                system_fonts.append({
+                                    'family': font_info['family'],
+                                    'display_name': font_info['display_name'],
+                                    'path': str(font_path),
+                                    'source': 'system',
+                                    'weight': 400
+                                })
+            
+            elif system == 'Linux':
+                font_dirs = [
+                    Path("/usr/share/fonts/truetype"),
+                    Path("/usr/share/fonts/TTF"),
+                    Path.home() / ".fonts"
+                ]
+                
+                for font_dir in font_dirs:
+                    if font_dir.exists():
+                        # 查找常见字体
+                        for font_file in font_dir.rglob("*.ttf"):
+                            font_name = font_file.stem.lower()
+                            if 'dejavu' in font_name or 'liberation' in font_name:
+                                system_fonts.append({
+                                    'family': font_file.stem,
+                                    'display_name': font_file.stem,
+                                    'path': str(font_file),
+                                    'source': 'system',
+                                    'weight': 400
+                                })
+        
+        except Exception as e:
+            logger.error(f"扫描系统字体失败: {e}")
+        
+        # 去重（按family和weight）
+        seen = set()
+        unique_fonts = []
+        for font in system_fonts:
+            key = (font['family'], font.get('weight', 400))
+            if key not in seen:
+                seen.add(key)
+                unique_fonts.append(font)
+        
+        self._system_fonts_cache = unique_fonts
+        return unique_fonts
+    
+    def find_font(self, font_family: str, font_weight: int = 400) -> Optional[str]:
+        """查找字体文件（按优先级：预置 > ziti > 系统 > 默认）
+        
+        Args:
+            font_family: 字体名称
+            font_weight: 字体粗细 (100-1000)
+        
+        Returns:
+            字体文件路径，如果找不到返回None
+        """
+        # 1. 优先查找预置字体
+        bundled_font = self._find_bundled_font(font_family, font_weight)
+        if bundled_font:
+            return bundled_font
+        
+        # 2. 查找ziti目录字体
+        ziti_font = self._find_ziti_font(font_family, font_weight)
+        if ziti_font:
+            return ziti_font
+        
+        # 3. 查找系统字体
+        system_font = self._find_system_font(font_family, font_weight)
+        if system_font:
+            return system_font
+        
+        # 4. 返回None（使用默认字体）
+        return None
+    
+    def _find_bundled_font(self, font_family: str, font_weight: int) -> Optional[str]:
+        """查找预置字体"""
+        if not self.bundled_fonts_dir.exists():
+            return None
+        
+        bundled_fonts = self.get_bundled_fonts()
+        
+        # 查找匹配的字体
+        for font_info in bundled_fonts:
+            if font_info.get('family') == font_family:
+                font_dir = self.bundled_fonts_dir / font_info.get('path', '')
+                
+                # 根据font_weight选择变体
+                variant = self._get_variant_for_weight(font_weight)
+                
+                # 查找字体文件（支持TTF和OTF格式）
+                for ext in [".ttf", ".otf"]:
+                    variant_file = font_dir / f"{variant}{ext}"
+                    if variant_file.exists():
+                        return str(variant_file)
+                
+                # 如果找不到指定变体，尝试查找Regular
+                for ext in [".ttf", ".otf"]:
+                    regular_file = font_dir / f"Regular{ext}"
+                    if regular_file.exists():
+                        return str(regular_file)
+        
+        return None
+    
+    def _find_ziti_font(self, font_family: str, font_weight: int) -> Optional[str]:
+        """查找ziti目录字体（支持模糊匹配和名称映射）"""
+        if not font_family:
+            return None
+            
+        ziti_fonts = self.scan_ziti_fonts()
+        
+        if not ziti_fonts:
+            logger.debug(f"ziti目录中没有字体文件，无法查找: {font_family}")
+            return None
+        
+        # 字体名称映射表（与前端保持一致）
+        # 映射：显示名称/别名 -> 文件名（不包含扩展名）
+        font_name_map = {
+            'Dymon手写体': 'Dymon-ShouXieTi',
+            'Dymon-ShouXieTi': 'Dymon-ShouXieTi',
+            '猫啃杂糅体': 'MaokenAssortedSans',
+            'MaokenAssortedSans': 'MaokenAssortedSans',
+            '猫啃杂糅体 Lite': 'MaokenAssortedSans-Lite',
+            'MaokenAssortedSans-Lite': 'MaokenAssortedSans-Lite',
+            'Murecho 黑体': 'Murecho-Black',
+            'Murecho-Black': 'Murecho-Black',
+            'Murecho 粗体': 'Murecho-Bold',
+            'Murecho-Bold': 'Murecho-Bold',
+            '墨趣古风体': '墨趣古风体',
+            '平方张亚玲黑方体': '平方张亚玲黑方体',
+            '胡晓波骚包体': '胡晓波骚包体2.0',
+            '胡晓波骚包体2.0': '胡晓波骚包体2.0',
+        }
+        
+        # 标准化字体名称（移除空格、统一大小写）
+        def normalize_name(name: str) -> str:
+            return name.replace(' ', '').replace('-', '').replace('_', '').lower()
+        
+        # 尝试通过映射表转换字体名称
+        mapped_font_family = font_name_map.get(font_family, font_family)
+        normalized_target = normalize_name(mapped_font_family)
+        
+        logger.debug(f"查找ziti字体: '{font_family}' -> 映射: '{mapped_font_family}' -> 标准化: '{normalized_target}', 权重: {font_weight}")
+        
+        # 查找匹配的字体
+        best_match = None
+        min_weight_diff = float('inf')
+        
+        for font_info in ziti_fonts:
+            family = font_info.get('family', '')
+            display_name = font_info.get('display_name', '')
+            path = font_info.get('path', '')
+            
+            # 获取文件名（不含扩展名）用于匹配
+            file_stem = None
+            if path:
+                from pathlib import Path
+                file_stem = Path(path).stem
+            
+            # 多种匹配方式：精确匹配、模糊匹配、文件名匹配
+            is_match = False
+            match_type = None
+            
+            # 1. 精确匹配
+            if family == font_family or family == mapped_font_family:
+                is_match = True
+                match_type = f"精确匹配(family={family})"
+            elif display_name == font_family or display_name == mapped_font_family:
+                is_match = True
+                match_type = f"精确匹配(display_name={display_name})"
+            # 2. 模糊匹配（忽略大小写和空格）
+            elif normalize_name(family) == normalized_target:
+                is_match = True
+                match_type = f"模糊匹配(family={family})"
+            elif normalize_name(display_name) == normalized_target:
+                is_match = True
+                match_type = f"模糊匹配(display_name={display_name})"
+            # 3. 文件名匹配
+            elif file_stem and normalize_name(file_stem) == normalized_target:
+                is_match = True
+                match_type = f"文件名匹配(file_stem={file_stem})"
+            
+            if is_match:
+                font_weight_info = font_info.get('weight', 400)
+                weight_diff = abs(font_weight_info - font_weight)
+                
+                logger.debug(f"找到匹配字体: {match_type}, 路径: {path}, 权重: {font_weight_info}, 权重差: {weight_diff}")
+                
+                # 找到权重最接近的字体
+                if weight_diff < min_weight_diff:
+                    min_weight_diff = weight_diff
+                    best_match = path
+        
+        if best_match:
+            logger.info(f"找到ziti字体 '{font_family}': {best_match}")
+        else:
+            logger.warning(f"未找到ziti字体 '{font_family}'，已扫描{len(ziti_fonts)}个字体文件")
+        
+        return best_match
+    
+    def _find_system_font(self, font_family: str, font_weight: int) -> Optional[str]:
+        """查找系统字体"""
+        system_fonts = self.scan_system_fonts()
+        
+        # 查找匹配的字体
+        for font_info in system_fonts:
+            if font_info.get('family') == font_family:
+                font_weight_info = font_info.get('weight', 400)
+                
+                # 如果权重匹配（或接近），返回字体路径
+                if abs(font_weight_info - font_weight) <= 100:
+                    return font_info.get('path')
+        
+        return None
+    
+    def _get_variant_for_weight(self, font_weight: int) -> str:
+        """根据字体权重获取变体名称"""
+        if font_weight >= 700:
+            return "Bold"
+        elif font_weight >= 600:
+            return "SemiBold"
+        elif font_weight >= 500:
+            return "Medium"
+        else:
+            return "Regular"
+    
+    def get_all_available_fonts(self) -> List[Dict]:
+        """获取所有可用字体（合并预置、ziti和系统字体）"""
+        all_fonts = []
+        
+        # 添加预置字体
+        bundled_fonts = self.get_bundled_fonts()
+        for font_info in bundled_fonts:
+            all_fonts.append({
+                'value': font_info.get('family'),
+                'label': font_info.get('display_name', font_info.get('family')),
+                'source': 'bundled',
+                'category': font_info.get('category', 'sans-serif'),
+                'languages': font_info.get('languages', [])
+            })
+        
+        # 添加ziti目录字体
+        ziti_fonts = self.scan_ziti_fonts()
+        seen_families = {f.get('family') for f in bundled_fonts}
+        
+        for font_info in ziti_fonts:
+            family = font_info.get('family')
+            if family not in seen_families:
+                all_fonts.append({
+                    'value': family,
+                    'label': font_info.get('display_name', family),
+                    'source': 'ziti',
+                    'category': font_info.get('category', 'sans-serif'),
+                    'languages': font_info.get('languages', []),
+                    'path': font_info.get('path')
+                })
+                seen_families.add(family)
+        
+        # 添加系统字体（去重）
+        system_fonts = self.scan_system_fonts()
+        
+        for font_info in system_fonts:
+            family = font_info.get('family')
+            if family not in seen_families:
+                all_fonts.append({
+                    'value': family,
+                    'label': font_info.get('display_name', family),
+                    'source': 'system',
+                    'category': 'sans-serif',
+                    'languages': []
+                })
+                seen_families.add(family)
+        
+        return all_fonts
+
+
+# 全局字体管理器实例
+_font_manager: Optional[FontManager] = None
+
+
+def get_font_manager() -> FontManager:
+    """获取全局字体管理器实例"""
+    global _font_manager
+    if _font_manager is None:
+        _font_manager = FontManager()
+    return _font_manager
+

scripts/cover/modules/utils.py

@@ -0,0 +1,312 @@
+"""
+工具函数模块
+提供字幕封面生成过程中需要的通用工具函数
+"""
+
+import os
+import sys
+from pathlib import Path
+from typing import Tuple, Optional, List, Dict, Any
+
+# 尝试导入loguru，如果不可用则使用print作为替代
+try:
+    from loguru import logger
+except ImportError:
+    # Fallback logger that uses print
+    class logger:
+        @staticmethod
+        def info(msg, *args, **kwargs):
+            print(f"[INFO] {msg}", file=sys.stderr)
+        @staticmethod
+        def warning(msg, *args, **kwargs):
+            print(f"[WARN] {msg}", file=sys.stderr)
+        @staticmethod
+        def error(msg, *args, **kwargs):
+            print(f"[ERROR] {msg}", file=sys.stderr)
+        @staticmethod
+        def debug(msg, *args, **kwargs):
+            print(f"[DEBUG] {msg}", file=sys.stderr)
+
+# 尝试导入图像处理库
+try:
+    import cv2
+    import numpy as np
+    CV2_AVAILABLE = True
+except ImportError:
+    CV2_AVAILABLE = False
+    logger.warning("opencv-python不可用，图像处理功能受限")
+
+try:
+    from PIL import Image
+    PIL_AVAILABLE = True
+except ImportError:
+    PIL_AVAILABLE = False
+    logger.warning("PIL不可用，图像处理功能受限")
+
+
+def ensure_dir(path: str) -> Path:
+    """确保目录存在"""
+    path_obj = Path(path)
+    path_obj.mkdir(parents=True, exist_ok=True)
+    return path_obj
+
+
+def get_video_info(video_path: str) -> Dict[str, Any]:
+    """获取视频信息"""
+    if not CV2_AVAILABLE:
+        # 如果opencv不可用，返回基本信息
+        try:
+            import os
+            file_size = os.path.getsize(video_path)
+            return {
+                'fps': 30,  # 默认值
+                'frame_count': 0,
+                'width': 1920,  # 默认值
+                'height': 1080,  # 默认值
+                'duration': 0,  # 未知
+                'path': video_path,
+                'file_size': file_size,
+                'note': '视频信息不完整，opencv不可用'
+            }
+        except Exception as e:
+            logger.error(f"获取基本视频信息失败: {e}")
+            raise
+
+    try:
+        cap = cv2.VideoCapture(video_path)
+        if not cap.isOpened():
+            raise ValueError(f"无法打开视频文件: {video_path}")
+
+        # 获取视频属性
+        fps = cap.get(cv2.CAP_PROP_FPS)
+        frame_count = int(cap.get(cv2.CAP_PROP_FRAME_COUNT))
+        width = int(cap.get(cv2.CAP_PROP_FRAME_WIDTH))
+        height = int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT))
+        duration = frame_count / fps if fps > 0 else 0
+
+        cap.release()
+
+        return {
+            'fps': fps,
+            'frame_count': frame_count,
+            'width': width,
+            'height': height,
+            'duration': duration,
+            'path': video_path
+        }
+    except Exception as e:
+        logger.error(f"获取视频信息失败: {e}")
+        raise
+
+
+def extract_frame_at_time(video_path: str, time_seconds: float):
+    """在指定时间抽取视频帧"""
+    if not CV2_AVAILABLE:
+        logger.warning("opencv不可用，无法抽取视频帧")
+        # 返回一个占位符
+        return None
+
+    try:
+        cap = cv2.VideoCapture(video_path)
+        if not cap.isOpened():
+            raise ValueError(f"无法打开视频文件: {video_path}")
+
+        # 设置帧位置
+        fps = cap.get(cv2.CAP_PROP_FPS)
+        frame_number = int(time_seconds * fps)
+        cap.set(cv2.CAP_PROP_POS_FRAMES, frame_number)
+
+        ret, frame = cap.read()
+        cap.release()
+
+        if not ret:
+            raise ValueError(f"无法读取帧: {frame_number}")
+
+        return frame
+    except Exception as e:
+        logger.error(f"抽帧失败: {e}")
+        raise
+
+
+def save_image(image, output_path: str, quality: int = 95) -> None:
+    """保存图像
+    
+    如果输出路径是PNG格式，会保留alpha通道（透明背景）
+    如果是JPEG格式，会转换为RGB格式
+    """
+    try:
+        ensure_dir(os.path.dirname(output_path))
+        
+        is_png = output_path.lower().endswith('.png')
+
+        if CV2_AVAILABLE and isinstance(image, np.ndarray):
+            # 使用OpenCV保存
+            if is_png and image.shape[2] == 4:
+                # PNG格式且有alpha通道，保存为BGRA（OpenCV使用BGR格式）
+                # 确保图像是BGRA格式（B, G, R, A）
+                # 如果输入是RGBA（R, G, B, A），需要转换为BGRA
+                if image.dtype != np.uint8:
+                    image = image.astype(np.uint8)
+                # OpenCV的imwrite会自动处理BGRA格式
+                success = cv2.imwrite(output_path, image, [cv2.IMWRITE_PNG_COMPRESSION, 3])
+            elif is_png:
+                # PNG格式但没有alpha通道，转换为RGB
+                if image.shape[2] == 3:
+                    success = cv2.imwrite(output_path, image, [cv2.IMWRITE_PNG_COMPRESSION, 3])
+                else:
+                    # 如果是单通道，转换为3通道
+                    if len(image.shape) == 2:
+                        image = cv2.cvtColor(image, cv2.COLOR_GRAY2BGR)
+                    success = cv2.imwrite(output_path, image, [cv2.IMWRITE_PNG_COMPRESSION, 3])
+            else:
+                # JPEG格式，确保是3通道BGR
+                if image.shape[2] == 4:
+                    # 有alpha通道，先合成到白色背景
+                    bgr = image[:, :, :3]
+                    alpha = image[:, :, 3:4] / 255.0
+                    white_bg = np.ones_like(bgr) * 255
+                    image = (bgr * alpha + white_bg * (1 - alpha)).astype(np.uint8)
+                elif len(image.shape) == 2:
+                    image = cv2.cvtColor(image, cv2.COLOR_GRAY2BGR)
+                success = cv2.imwrite(output_path, image, [cv2.IMWRITE_JPEG_QUALITY, quality])
+            
+            if not success:
+                raise ValueError(f"保存图像失败: {output_path}")
+        elif PIL_AVAILABLE and hasattr(image, 'save'):
+            # 使用PIL保存
+            if is_png:
+                image.save(output_path, 'PNG', compress_level=3)
+            else:
+                # JPEG格式，确保是RGB
+                if image.mode == 'RGBA':
+                    # 合成到白色背景
+                    rgb = Image.new('RGB', image.size, (255, 255, 255))
+                    rgb.paste(image, mask=image.split()[3])
+                    image = rgb
+                image.save(output_path, 'JPEG', quality=quality)
+        else:
+            raise ValueError("没有可用的图像保存方法")
+
+        logger.info(f"图像已保存: {output_path}")
+    except Exception as e:
+        logger.error(f"保存图像失败: {e}")
+        raise
+
+
+def format_time(seconds: float) -> str:
+    """格式化时间为 HH:MM:SS.mmm"""
+    hours = int(seconds // 3600)
+    minutes = int((seconds % 3600) // 60)
+    secs = int(seconds % 60)
+    milliseconds = int((seconds % 1) * 1000)
+
+    return "02d"
+
+
+def create_temp_dir(prefix: str = "subtitle_cover_") -> str:
+    """创建临时目录"""
+    import tempfile
+    temp_dir = tempfile.mkdtemp(prefix=prefix)
+    logger.info(f"创建临时目录: {temp_dir}")
+    return temp_dir
+
+
+def cleanup_temp_dir(temp_dir: str) -> None:
+    """清理临时目录"""
+    try:
+        import shutil
+        if os.path.exists(temp_dir):
+            shutil.rmtree(temp_dir)
+            logger.info(f"清理临时目录: {temp_dir}")
+    except Exception as e:
+        logger.warning(f"清理临时目录失败: {e}")
+
+
+def validate_file_exists(file_path: str, file_type: str = "文件") -> None:
+    """验证文件是否存在"""
+    if not os.path.exists(file_path):
+        raise FileNotFoundError(f"{file_type}不存在: {file_path}")
+
+    if not os.path.isfile(file_path):
+        raise ValueError(f"{file_type}不是文件: {file_path}")
+
+
+def get_file_size_mb(file_path: str) -> float:
+    """获取文件大小(MB)"""
+    size_bytes = os.path.getsize(file_path)
+    return size_bytes / (1024 * 1024)
+
+
+def calculate_aspect_ratio(width: int, height: int) -> float:
+    """计算宽高比"""
+    return width / height if height > 0 else 0
+
+
+def resize_image(image: np.ndarray, target_width: int, target_height: int,
+                keep_aspect_ratio: bool = True) -> np.ndarray:
+    """调整图像大小"""
+    if keep_aspect_ratio:
+        # 保持宽高比
+        h, w = image.shape[:2]
+        aspect_ratio = w / h
+
+        if target_width / target_height > aspect_ratio:
+            # 目标更宽，以高度为准
+            new_width = int(target_height * aspect_ratio)
+            new_height = target_height
+        else:
+            # 目标更高，以宽度为准
+            new_width = target_width
+            new_height = int(target_width / aspect_ratio)
+
+        resized = cv2.resize(image, (new_width, new_height))
+    else:
+        # 不保持宽高比，直接缩放
+        resized = cv2.resize(image, (target_width, target_height))
+
+    return resized
+
+
+def blend_images(background: np.ndarray, foreground: np.ndarray,
+                position: Tuple[int, int] = (0, 0)) -> np.ndarray:
+    """将前景图像合成到背景图像上"""
+    x, y = position
+    h, w = foreground.shape[:2]
+
+    # 确保位置不超出边界
+    bg_h, bg_w = background.shape[:2]
+    x = max(0, min(x, bg_w - w))
+    y = max(0, min(y, bg_h - h))
+
+    # 创建ROI
+    roi = background[y:y+h, x:x+w]
+
+    # 如果前景有alpha通道，进行透明合成
+    if foreground.shape[2] == 4:
+        # 分离颜色和alpha通道
+        foreground_rgb = foreground[:, :, :3]
+        alpha = foreground[:, :, 3] / 255.0
+
+        # 扩展alpha到3通道
+        alpha = np.stack([alpha] * 3, axis=2)
+
+        # 透明合成
+        blended = foreground_rgb * alpha + roi * (1 - alpha)
+        background[y:y+h, x:x+w] = blended.astype(np.uint8)
+    else:
+        # 直接覆盖
+        background[y:y+h, x:x+w] = foreground
+
+    return background
+
+
+def apply_blur(image: np.ndarray, kernel_size: int = 15) -> np.ndarray:
+    """应用模糊效果"""
+    return cv2.GaussianBlur(image, (kernel_size, kernel_size), 0)
+
+
+def apply_gradient_overlay(image: np.ndarray, color: Tuple[int, int, int],
+                          opacity: float = 0.5) -> np.ndarray:
+    """应用渐变覆盖"""
+    overlay = np.full_like(image, color, dtype=np.uint8)
+    return cv2.addWeighted(image, 1 - opacity, overlay, opacity, 0)