优化语言一致性逻辑

pixelle_video/pipelines/asset_based.py

@@ -308,6 +308,8 @@ class AssetBasedPipeline(LinearVideoPipeline):
         Returns:
             Updated context with generated script (scenes already have asset_path assigned)
         """
+        from pixelle_video.prompts.asset_script_generation import build_asset_script_prompt
+        
         logger.info("🤖 Generating video script with LLM...")
         
         # Emit progress for script generation (15% - 25%)
@@ -328,34 +330,13 @@ class AssetBasedPipeline(LinearVideoPipeline):
         
         assets_text = "\n".join(asset_info)
         
-        # Build title section for prompt (only if title is provided)
-        title_section = f"- Video Title: {title}\n" if title else ""
-        
-        prompt = f"""You are a video script writer. Generate a {duration}-second video script.
-
-## Requirements
-{title_section}- Intent: {intent}
-- Target Duration: {duration} seconds
-
-## Available Assets (use the exact path in your response)
-{assets_text}
-
-## Instructions
-1. Decide how many scenes are needed based on the target duration (typically 5-15 seconds per scene)
-2. For each scene, directly assign ONE asset from the available assets above
-3. Each scene can have 1-5 narration sentences
-4. Try to use all available assets, but it's OK to reuse if needed
-5. Total duration of all scenes should be approximately {duration} seconds
-{f"6. The narrations should align with the video title: {title}" if title else ""}
-
-## Output Requirements
-For each scene, provide:
-- scene_number: Sequential number starting from 1
-- asset_path: The EXACT path from the available assets list
-- narrations: Array of 1-5 narration sentences
-- duration: Estimated duration in seconds
-
-Generate the video script now:"""
+        # Build prompt using the centralized prompt function
+        prompt = build_asset_script_prompt(
+            intent=intent,
+            duration=duration,
+            assets_text=assets_text,
+            title=title
+        )
         
         # Call LLM with structured output
         script: VideoScript = await self.core.llm(

pixelle_video/prompts/asset_script_generation.py

@@ -0,0 +1,80 @@
+# Copyright (C) 2025 AIDC-AI
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#     http://www.apache.org/licenses/LICENSE-2.0
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+Asset-based video script generation prompt
+
+For generating video scripts based on user-provided assets.
+"""
+
+
+ASSET_SCRIPT_GENERATION_PROMPT = """你是一位专业的视频脚本创作者。请基于用户提供的视频意图和可用素材，生成一个 {duration} 秒的视频脚本。
+
+## 需求信息
+{title_section}- 视频意图：{intent}
+- 目标时长：{duration} 秒
+
+## 可用素材（请在输出中使用精确路径）
+{assets_text}
+
+## 创作指南
+1. 根据目标时长决定需要多少个场景（通常每个场景 5-15 秒）
+2. 为每个场景从可用素材中直接分配一个素材
+3. 每个场景可以包含 1-3 句旁白
+4. 尽量使用所有可用素材，但如有需要可以复用素材
+5. 所有场景的总时长应约等于 {duration} 秒
+{title_instruction}
+
+## 语言一致性要求（非常重要）
+- 旁白的语言必须与用户输入的视频意图保持一致
+- 如果视频意图是中文，则旁白必须是中文
+- 如果视频意图是英文，则旁白必须是英文
+- 除非视频意图中明确指定了输出语言，否则严格遵循意图的原始语言
+
+## 输出要求
+为每个场景提供：
+- scene_number: 场景编号（从 1 开始）
+- asset_path: 从可用素材列表中选择的精确路径
+- narrations: 包含 1-3 句旁白的数组
+- duration: 预估时长（秒）
+
+现在请开始生成视频脚本："""
+
+
+def build_asset_script_prompt(
+    intent: str,
+    duration: int,
+    assets_text: str,
+    title: str = ""
+) -> str:
+    """
+    Build asset-based script generation prompt
+    
+    Args:
+        intent: Video intent/purpose
+        duration: Target duration in seconds
+        assets_text: Formatted text of available assets with descriptions
+        title: Optional video title
+    
+    Returns:
+        Formatted prompt
+    """
+    title_section = f"- 视频标题：{title}\n" if title else ""
+    title_instruction = f"6. 旁白内容应与视频标题保持一致：{title}\n" if title else ""
+    
+    return ASSET_SCRIPT_GENERATION_PROMPT.format(
+        duration=duration,
+        title_section=title_section,
+        intent=intent,
+        assets_text=assets_text,
+        title_instruction=title_instruction
+    )