Files
xiaoxia-saas/packages/domain/subtitle_style.py

273 lines
8.9 KiB
Python
Executable File
Raw Permalink Blame History

This file contains ambiguous Unicode characters
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
"""字幕样式领域模型 — 纯逻辑,无外部依赖.
抽离自 subtitle_render_engine.py 的数据类和工具函数,
方便单测覆盖,同时保持向后兼容。
"""
from __future__ import annotations
from dataclasses import dataclass
from typing import Any
# ── 常量 ──────────────────────────────────────────────────────────────────────
# 9宫格位置映射(ASS alignment 编号)
POSITION_ALIGNMENT: dict[str, int] = {
"top_left": 7,
"top_center": 8,
"top_right": 9,
"middle_left": 4,
"center": 5,
"middle_right": 6,
"bottom_left": 1,
"bottom_center": 2,
"bottom_right": 3,
}
# 位置简称兼容
POSITION_ALIASES: dict[str, str] = {
"top": "top_center",
"bottom": "bottom_center",
"middle": "center",
"left": "middle_left",
"right": "middle_right",
}
DEFAULT_FONT = "思源黑体"
DEFAULT_FONT_SIZE = 24
DEFAULT_COLOR = "#FFFFFF"
DEFAULT_STROKE_COLOR = "#000000"
DEFAULT_STROKE_WIDTH = 1.5
DEFAULT_POSITION = "bottom_center"
DEFAULT_MAX_CHARS_PER_LINE = 20
ALLOWED_SUBTITLE_EXTENSIONS = {".srt", ".ass", ".vtt", ".sub"}
# ── 工具函数 ──────────────────────────────────────────────────────────────────
def hex_to_ass_color(hex_color: str) -> str:
"""HEX → ASS 颜色 &HAABBGGRR(默认不透明)."""
hex_color = hex_color.lstrip("#")
if len(hex_color) != 6:
return "&H00FFFFFF"
r, g, b = hex_color[0:2], hex_color[2:4], hex_color[4:6]
return f"&H00{b.upper()}{g.upper()}{r.upper()}"
def hex_to_ass_bgr(hex_color: str) -> str:
"""HEX → ASS BGR 部分(不含 alpha."""
hex_color = hex_color.lstrip("#")
if len(hex_color) != 6:
return "FFFFFF"
r, g, b = hex_color[0:2], hex_color[2:4], hex_color[4:6]
return f"{b.upper()}{g.upper()}{r.upper()}"
def opacity_to_ass_alpha(opacity: float) -> str:
"""不透明度 → ASS alpha00=不透明,FF=完全透明)."""
alpha = 255 - int(max(0.0, min(1.0, opacity)) * 255)
return f"{alpha:02X}"
def escape_ass_text(text: str) -> str:
"""转义 ASS 文本特殊字符."""
text = text.replace("\r\n", "\\N").replace("\n", "\\N").replace("\r", "\\N")
text = text.replace("{", "(").replace("}", ")")
return text
def format_ass_time(seconds: float) -> str:
"""秒 → ASS 时间格式 H:MM:SS.cc."""
if seconds < 0:
seconds = 0.0
hours = int(seconds // 3600)
minutes = int((seconds % 3600) // 60)
secs = seconds % 60
return f"{hours}:{minutes:02d}:{secs:05.2f}"
def wrap_text(text: str, max_chars: int) -> list[str]:
"""按字数换行,优先标点断开."""
if max_chars <= 0:
return [text]
if not text or len(text) <= max_chars:
return [text]
lines: list[str] = []
remaining = text
punctuations = ",。!?、;:,.;:!?"
while len(remaining) > max_chars:
break_point = max_chars
# 在 max_chars 到 max_chars//2 之间寻找标点断点
for i in range(max_chars, max_chars // 2, -1):
if i < len(remaining) and remaining[i] in punctuations:
break_point = i + 1
break
lines.append(remaining[:break_point])
remaining = remaining[break_point:]
if remaining:
lines.append(remaining)
return lines
# ── 字幕样式配置 ────────────────────────────────────────────────────────────
@dataclass
class SubtitleStyle:
"""字幕样式配置."""
font_name: str = DEFAULT_FONT
font_size: int = DEFAULT_FONT_SIZE
font_color: str = DEFAULT_COLOR
bold: bool = False
italic: bool = False
# 描边
stroke_enabled: bool = True
stroke_color: str = DEFAULT_STROKE_COLOR
stroke_width: float = DEFAULT_STROKE_WIDTH
# 阴影
shadow_enabled: bool = False
shadow_color: str = "#000000"
shadow_offset_x: int = 2
shadow_offset_y: int = 2
shadow_blur: float = 0.0
# 背景框
background_enabled: bool = False
background_color: str = "#000000"
background_opacity: float = 0.5
background_padding: int = 8
background_radius: int = 4
# 位置
position: str = DEFAULT_POSITION
margin_v: int = 60
margin_l: int = 40
margin_r: int = 40
# 多行
max_chars_per_line: int = DEFAULT_MAX_CHARS_PER_LINE
line_spacing: int = 0
# 动画
fade_in: float = 0.0
fade_out: float = 0.0
animation_type: str = "none"
@classmethod
def from_dict(cls, config: dict[str, Any] | None) -> "SubtitleStyle":
"""从字典创建样式配置,带安全类型转换."""
if not config or not isinstance(config, dict):
return cls()
def safe_str(key: str, default: str) -> str:
val = config.get(key, default)
return str(val) if val is not None else default
def safe_int(key: str, default: int) -> int:
try:
return int(config.get(key, default))
except (TypeError, ValueError):
return default
def safe_float(key: str, default: float) -> float:
try:
return float(config.get(key, default))
except (TypeError, ValueError):
return default
def safe_bool(key: str, default: bool) -> bool:
return bool(config.get(key, default))
position = safe_str("position", DEFAULT_POSITION)
position = POSITION_ALIASES.get(position, position)
if position not in POSITION_ALIGNMENT:
position = DEFAULT_POSITION
return cls(
font_name=safe_str("font", DEFAULT_FONT),
font_size=safe_int("size", DEFAULT_FONT_SIZE),
font_color=safe_str("color", DEFAULT_COLOR),
bold=safe_bool("bold", False),
italic=safe_bool("italic", False),
stroke_enabled=safe_bool("stroke_enabled", True),
stroke_color=safe_str("stroke_color", DEFAULT_STROKE_COLOR),
stroke_width=safe_float("stroke_width", DEFAULT_STROKE_WIDTH),
shadow_enabled=safe_bool("shadow_enabled", False),
shadow_color=safe_str("shadow_color", "#000000"),
shadow_offset_x=safe_int("shadow_offset_x", 2),
shadow_offset_y=safe_int("shadow_offset_y", 2),
shadow_blur=safe_float("shadow_blur", 0.0),
background_enabled=safe_bool("background_enabled", False),
background_color=safe_str("background_color", "#000000"),
background_opacity=max(0.0, min(1.0, safe_float("background_opacity", 0.5))),
background_padding=safe_int("background_padding", 8),
background_radius=safe_int("background_radius", 4),
position=position,
margin_v=safe_int("margin_v", 60),
margin_l=safe_int("margin_l", 40),
margin_r=safe_int("margin_r", 40),
max_chars_per_line=safe_int("max_chars_per_line", DEFAULT_MAX_CHARS_PER_LINE),
line_spacing=safe_int("line_spacing", 0),
fade_in=max(0.0, safe_float("fade_in", 0.0)),
fade_out=max(0.0, safe_float("fade_out", 0.0)),
animation_type=safe_str("animation_type", "none"),
)
@property
def alignment(self) -> int:
"""获取 ASS alignment 编号."""
return POSITION_ALIGNMENT.get(self.position, 2)
@property
def ass_font_color(self) -> str:
"""ASS 格式颜色 &HAABBGGRR."""
return hex_to_ass_color(self.font_color)
@property
def ass_stroke_color(self) -> str:
return hex_to_ass_color(self.stroke_color)
@property
def ass_shadow_color(self) -> str:
return hex_to_ass_color(self.shadow_color)
@property
def ass_background_color(self) -> str:
"""背景框颜色(ASS BackColour),带透明度."""
alpha_hex = opacity_to_ass_alpha(self.background_opacity)
color_bgr = hex_to_ass_bgr(self.background_color)
return f"&H{alpha_hex}{color_bgr}"
# ── 字幕片段 ──────────────────────────────────────────────────────────────────
@dataclass
class SubtitleSegment:
"""单个字幕片段."""
start: float # 开始时间(秒)
end: float # 结束时间(秒)
text: str # 字幕文本
style_name: str = "Default" # 使用的样式名
@property
def duration(self) -> float:
"""字幕时长."""
return max(0.0, self.end - self.start)
@property
def is_valid(self) -> bool:
"""是否有效(有文本且时长>0."""
return bool(self.text) and self.end > self.start