packages/domain/ass_subtitle_builder.py

@@ -247,6 +247,27 @@ def build_ass_content(
     title_config = title_config or {}
     subtitle_config = subtitle_config or {}
 
+    # ── 兼容前端简化格式：stroke/shadow 为 boolean 时，转换为标准 dict ──
+    # 前端 TitleSettings 发送 stroke=true/false, shadow=true/false
+    # 后端 build_ass_style 期望 stroke={enabled, color, width}, shadow={enabled, blur, offset_x, offset_y}
+    if title_config:
+        _stroke_val = title_config.get("stroke")
+        if isinstance(_stroke_val, bool):
+            title_config["stroke"] = {
+                "enabled": _stroke_val,
+                "color": "#000000",
+                "width": 2,
+            } if _stroke_val else {"enabled": False}
+        _shadow_val = title_config.get("shadow")
+        if isinstance(_shadow_val, bool):
+            title_config["shadow"] = {
+                "enabled": _shadow_val,
+                "color": "#000000",
+                "blur": 4,
+                "offset_x": 2,
+                "offset_y": 2,
+            } if _shadow_val else {"enabled": False}
+
     title_enabled = title_config.get("enabled", True) and bool(title_text.strip())
     subtitle_enabled = subtitle_config.get("enabled", True) and bool(subtitle_text.strip())
 
@@ -262,7 +283,7 @@ def build_ass_content(
         title_stroke = title_config.get("stroke", {}) or {}
         title_shadow = title_config.get("shadow", {}) or {}
         stroke_color = hex_to_ass_color(title_stroke.get("color", "#000000"))
-        stroke_width = float(title_stroke.get("width", 1)) if title_stroke.get("enabled", False) else 0.0
+        stroke_width = float(title_stroke.get("width", 2)) if title_stroke.get("enabled", False) else 0.0
         shadow_blur = float(title_shadow.get("blur", 4)) if title_shadow.get("enabled", False) else 0.0
         shadow_offset = (
             title_shadow.get("offset_x", 2) if title_shadow.get("enabled", False) else 0,
@@ -275,7 +296,7 @@ def build_ass_content(
             build_ass_style(
                 "TitleStyle",
                 font_name=title_config.get("font", "思源黑体"),
-                font_size=int(title_config.get("size", 48)),
+                font_size=min(int(title_config.get("size", 36)), 36),
                 primary_color=title_color,
                 outline_color=stroke_color,
                 outline_width=stroke_width,
@@ -292,7 +313,7 @@ def build_ass_content(
 
         # 根据视频宽度和字号自动换行标题，防止超出画面
         # 先 escape 特殊字符，再插入换行符 \N，避免顺序颠倒导致 \N 被转义
-        title_font_size = int(title_config.get("size", 48))
+        title_font_size = min(int(title_config.get("size", 36)), 36)
         safe_title_text_raw = escape_ass_text(title_text)
         safe_title_text = _wrap_title_text(safe_title_text_raw, video_width, title_font_size)
 

tests/unit/test_title_render_consistency.py

@@ -0,0 +1,215 @@
+"""标题渲染前后端一致性测试。
+
+验证 build_ass_content 生成的 ASS 样式参数与前端 drawTitleOnCanvas.ts 一致：
+- 字号上限 36px
+- 描边宽度 2px
+- 阴影 blur=4, offset=2
+- boolean stroke/shadow 自动转换
+"""
+
+import sys
+from pathlib import Path
+
+# Ensure packages is importable
+sys.path.insert(0, str(Path(__file__).resolve().parents[2] / "packages"))
+
+from domain.ass_subtitle_builder import build_ass_content, build_ass_style
+
+
+class TestFontSizeCap:
+    """字号上限应与前端 Math.min(settings.size, 36) 一致。"""
+
+    def test_default_font_size_is_36(self):
+        """无 size 字段时，默认字号应为 36。"""
+        config = {"text": "test"}
+        content = build_ass_content(
+            video_width=1080,
+            video_height=1920,
+            video_duration=10.0,
+            title_text="测试标题",
+            title_config=config,
+        )
+        assert ",36," in content, f"默认字号应为36，实际内容: {content}"
+
+    def test_size_32_preserved(self):
+        """size=32 应原样使用。"""
+        config = {"size": 32}
+        content = build_ass_content(
+            video_width=1080,
+            video_height=1920,
+            video_duration=10.0,
+            title_text="测试标题",
+            title_config=config,
+        )
+        assert ",32," in content
+
+    def test_size_60_capped_at_36(self):
+        """size=60 应被 cap 到 36。"""
+        config = {"size": 60}
+        content = build_ass_content(
+            video_width=1080,
+            video_height=1920,
+            video_duration=10.0,
+            title_text="测试标题",
+            title_config=config,
+        )
+        # 解析 Style 行的 Fontsize 字段（第3个字段，索引2）
+        style_line = [line for line in content.splitlines() if line.startswith("Style: TitleStyle")][0]
+        fields = [f.strip() for f in style_line.split(",")]
+        font_size = int(fields[2])
+        assert font_size == 36, f"字号60应被cap到36, 实际={font_size}"
+
+    def test_size_24_preserved(self):
+        """size=24 应原样使用（小于36，不cap）。"""
+        config = {"size": 24}
+        content = build_ass_content(
+            video_width=1080,
+            video_height=1920,
+            video_duration=10.0,
+            title_text="测试标题",
+            title_config=config,
+        )
+        assert ",24," in content
+
+
+class TestBooleanStrokeNormalization:
+    """前端 stroke=true/false 应自动转换为标准 dict。"""
+
+    def test_stroke_true_enables_outline(self):
+        """stroke=true 应生成 outline_width=2 的样式。"""
+        config = {"stroke": True}
+        content = build_ass_content(
+            video_width=1080,
+            video_height=1920,
+            video_duration=10.0,
+            title_text="测试标题",
+            title_config=config,
+        )
+        # 解析 Style 行的 Outline 字段（第17个字段，索引16）
+        style_line = [line for line in content.splitlines() if line.startswith("Style: TitleStyle")][0]
+        fields = [f.strip() for f in style_line.split(",")]
+        outline_width = float(fields[16])
+        assert outline_width == 2.0, f"stroke=true 应产生 outline_width=2, 实际={outline_width}"
+
+    def test_stroke_false_no_outline(self):
+        """stroke=false 应生成 outline_width=0 的样式。"""
+        config = {"stroke": False}
+        content = build_ass_content(
+            video_width=1080,
+            video_height=1920,
+            video_duration=10.0,
+            title_text="测试标题",
+            title_config=config,
+        )
+        style_line = [line for line in content.splitlines() if line.startswith("Style: TitleStyle")][0]
+        fields = [f.strip() for f in style_line.split(",")]
+        outline_width = float(fields[16])
+        assert outline_width == 0.0, f"stroke=false 应产生 outline_width=0, 实际={outline_width}"
+
+    def test_stroke_dict_still_works(self):
+        """stroke={enabled:true, width:3} 仍应正常工作。"""
+        config = {"stroke": {"enabled": True, "width": 3, "color": "#FF0000"}}
+        content = build_ass_content(
+            video_width=1080,
+            video_height=1920,
+            video_duration=10.0,
+            title_text="测试标题",
+            title_config=config,
+        )
+        style_line = [line for line in content.splitlines() if line.startswith("Style: TitleStyle")][0]
+        fields = [f.strip() for f in style_line.split(",")]
+        outline_width = float(fields[16])
+        assert outline_width == 3.0, f"自定义stroke width=3 应保留, 实际={outline_width}"
+
+
+class TestBooleanShadowNormalization:
+    """前端 shadow=true/false 应自动转换为标准 dict。"""
+
+    def test_shadow_true_enables_shadow(self):
+        """shadow=true 应生成 shadow_depth=2 的样式。"""
+        config = {"shadow": True}
+        content = build_ass_content(
+            video_width=1080,
+            video_height=1920,
+            video_duration=10.0,
+            title_text="测试标题",
+            title_config=config,
+        )
+        style_line = [line for line in content.splitlines() if line.startswith("Style: TitleStyle")][0]
+        fields = [f.strip() for f in style_line.split(",")]
+        # Shadow 字段是第18个（索引17）
+        shadow_depth = int(fields[17])
+        assert shadow_depth == 2, f"shadow=true 应产生 shadow_depth=2, 实际={shadow_depth}"
+
+    def test_shadow_false_no_shadow(self):
+        """shadow=false 应生成 shadow_depth=0 的样式。"""
+        config = {"shadow": False}
+        content = build_ass_content(
+            video_width=1080,
+            video_height=1920,
+            video_duration=10.0,
+            title_text="测试标题",
+            title_config=config,
+        )
+        style_line = [line for line in content.splitlines() if line.startswith("Style: TitleStyle")][0]
+        fields = [f.strip() for f in style_line.split(",")]
+        shadow_depth = int(fields[17])
+        assert shadow_depth == 0, f"shadow=false 应产生 shadow_depth=0, 实际={shadow_depth}"
+
+    def test_shadow_dict_still_works(self):
+        """shadow={enabled:true, blur:8} 仍应正常工作。"""
+        config = {"shadow": {"enabled": True, "blur": 8, "offset_x": 3, "offset_y": 3}}
+        content = build_ass_content(
+            video_width=1080,
+            video_height=1920,
+            video_duration=10.0,
+            title_text="测试标题",
+            title_config=config,
+        )
+        style_line = [line for line in content.splitlines() if line.startswith("Style: TitleStyle")][0]
+        fields = [f.strip() for f in style_line.split(",")]
+        shadow_depth = int(fields[17])
+        assert shadow_depth == 3, f"自定义shadow offset_y=3 应保留, 实际={shadow_depth}"
+
+
+class TestFullStyleConsistency:
+    """完整样式参数一致性测试。"""
+
+    def test_frontend_default_style_matches_backend(self):
+        """前端默认样式参数应在后端产生一致的 ASS 输出。
+
+        前端默认：font_size=24(或用户设置), bold=false, stroke=true, shadow=true, color=#FFFFFF
+        """
+        config = {
+            "text": "标题文本",
+            "font": "思源黑体",
+            "size": 28,
+            "color": "#FFFFFF",
+            "bold": True,
+            "italic": False,
+            "stroke": True,
+            "shadow": True,
+            "position": "top",
+        }
+        content = build_ass_content(
+            video_width=1080,
+            video_height=1920,
+            video_duration=10.0,
+            title_text="标题文本",
+            title_config=config,
+        )
+        style_line = [line for line in content.splitlines() if line.startswith("Style: TitleStyle")][0]
+        fields = [f.strip() for f in style_line.split(",")]
+
+        # Fontname
+        assert fields[1] == "思源黑体"
+        # Fontsize = 28 (小于36，不cap)
+        assert fields[2] == "28"
+        # Bold = -1 (True)
+        assert fields[7] == "-1"
+        # Outline width = 2 (前端默认 stroke width)
+        assert float(fields[16]) == 2.0
+        # Shadow depth = 2 (offset_y)
+        assert int(fields[17]) == 2
+        # Alignment = 8 (top)
+        assert int(fields[18]) == 8