更新时间:2026-07-03 GMT+08:00
视频帧描述与摘要生成示例
本示例将介绍如何使用API实现以下功能:
- 使用UDTF(用户定义表函数)提取关键视频帧并生成对应的帧描述。
- 应用UDAF(用户定义聚合函数)将多个帧描述综合成连贯的视频摘要。
环境准备
本示例需要以下Python包:
huawei-aura-frame huawei-aura-connectorapi torch transformers
操作步骤
- 创建服务器连接。
import os from aura_frame.multimodal import ai_lake from contextlib import contextmanager # Set the target database name target_database = "xxxxx" def create_connect(): con = ai_lake.connect( aura_endpoint=os.getenv("aura_endpoint"), aura_endpoint_name=os.getenv("aura_endpoint_name"), aura_workspace_id=os.getenv("aura_workspace_id"), lf_catalog_name=os.getenv("lf_catalog_name"), access_key=os.getenv("access_key"), secret_key=os.getenv("secret_key"), default_database=target_database, use_single_cn_mode=True ) print(f"Establish ai_lake.connect: {conn}") try: yield conn finally: # release resource conn.close() - 定义UDF生成视频帧描述。
本示例使用Hugging Face的Salesforce/blip-image-captioning-base模型作为图像到文本生成模型。
由于数据库中的Python UDF目前不提供可靠的网络连接和下载功能,建议将原始模型下载到本地并通过OBS上传压缩文件(如.zip)。
可以通过以下Python脚本在本地机器上下载Salesforce/blip-image-captioning-base:
from huggingface_hub import snapshot_download local_dir = "blip-image-captioning-base" snapshot_download( repo_id="Salesforce/blip-image-captioning-base", local_dir=local_dir, local_dir_use_symlinks=False, )class VideoContentAnalyzer: def __init__(self, model_name="./blip-image-captioning-base"): import torch from transformers import BlipProcessor, BlipForConditionalGeneration self.device = "cuda" if torch.cuda.is_available() else "cpu" self.processor = BlipProcessor.from_pretrained(model_name) self.model = BlipForConditionalGeneration.from_pretrained( model_name, torch_dtype=torch.float16 if self.device == "cuda" else torch.float32 ).to(self.device) self.model.eval() def __call__(self, frame: bytes, frame_index: int) -> str: import json analyse = self.analyze_frame(frame, frame_index) return json.dumps({"description": analyse}) def analyze_frame(self, frame: bytes, frame_index: int): """Analyze the video frame content.""" try: # Generate frame description. frame_description = self._generate_frame_description(frame) # Analyze content features. content_features = self._analyze_content_features(frame_description) analyse = { 'frame_index': frame_index, 'description': frame_description, 'content_type': content_features['content_type'], 'key_objects': content_features['key_objects'], 'scene_context': content_features['scene_context'] } except Exception as e: # Current frame processing failed; return None. analyse = {} return analyse def _generate_frame_description(self, frame: bytes): import io from PIL import Image import torch pil_img = Image.open(io.BytesIO(frame)).convert("RGB") """Generate a single-frame description.""" inputs = self.processor(images=pil_img, return_tensors="pt").to(self.device) with torch.no_grad(): outputs = self.model.generate( **inputs, max_length=50, num_beams=5, early_stopping=True ) description = self.processor.decode(outputs[0], skip_special_tokens=True) return description.strip() def _analyze_content_features(self, description): description_lower = description.lower() content_categories = { 'educational': ['tutorial', 'lesson', 'explain', 'teach', 'learn', 'education'], 'entertainment': ['funny', 'comedy', 'entertainment', 'show', 'performance'], 'nature': ['outdoor', 'nature', 'landscape', 'mountain', 'forest', 'animal'], 'sports': ['sport', 'game', 'player', 'team', 'match', 'competition'], 'food': ['food', 'cooking', 'recipe', 'meal', 'restaurant', 'kitchen'], 'technology': ['computer', 'tech', 'device', 'electronic', 'software'], 'people': ['person', 'people', 'man', 'woman', 'child', 'group'] } detected_categories = [] for category, keywords in content_categories.items(): if any(keyword in description_lower for keyword in keywords): detected_categories.append(category) common_objects = [ 'person', 'people', 'man', 'woman', 'child', 'car', 'building', 'tree', 'house', 'street', 'water', 'sky', 'food', 'animal' ] key_objects = [obj for obj in common_objects if obj in description_lower] if any(word in description_lower for word in ['indoors', 'inside', 'room']): scene_context = 'indoor' elif any(word in description_lower for word in ['outdoors', 'outside', 'park', 'street']): scene_context = 'outdoor' else: scene_context = 'unknown' return { 'content_type': detected_categories[:2] if detected_categories else ['general'], 'key_objects': key_objects[:5], 'scene_context': scene_context } - 定义UDAF从多个帧描述生成视频摘要。
以下示例使用Hugging Face的google-t5/t5-small模型作为文本到文本生成模型。
由于数据库中的Python UDF目前不提供可靠的网络连接和下载功能,建议将原始模型下载到本地并通过OBS上传压缩文件(如.zip)。
from collections import Counter import typing class VideoSummaryGenerator: """Video Summary Generator""" def __init__(self, model): # Initialize the text summarization model. self.summarizer = pipeline( "text-generation", model=model, device=0 if torch.cuda.is_available() else -1 ) def generate_summary(self, frame_analyses): """Generate a video summary""" all_descriptions = [analysis['description'] for analysis in frame_analyses] if not all_descriptions: return "Unable to analyze the video content." # Analyze the characteristics of the video content. content_analysis = self._analyze_video_content(frame_analyses) # Generate a summary summary = self._generate_detailed_summary(all_descriptions, content_analysis) return summary def _analyze_video_content(self, frame_analyses): """Analyze the overall video content.""" # all_descriptions = ' '.join([analysis['description'] for analysis in frame_analyses]).lower() # Extract the key information content_types = [] all_objects = [] for analysis in frame_analyses: content_types.extend(analysis['content_type']) all_objects.extend(analysis['key_objects']) # Calculate frequency common_content_types = [item for item, count in Counter(content_types).most_common(2)] common_objects = [item for item, count in Counter(all_objects).most_common(5)] return { 'primary_categories': common_content_types, 'dominant_objects': common_objects, 'total_frames_analyzed': len(frame_analyses) } def _create_description_text(self, descriptions, content_analysis): """Create descriptive text.""" desc_counter = Counter(descriptions) representative_descs = [desc for desc, count in desc_counter.most_common(3)] text = "Video Content Analysis:\n" text += f"Primary Categories: {', '.join(content_analysis['primary_categories'])}\n" text += f"Key Objects: {', '.join(content_analysis['dominant_objects'][:3])}\n" text += "Representative Scenes:\n" for i, desc in enumerate(representative_descs, 1): text += f"{i}. {desc}\n" return text def _generate_concise_summary(self, content_analysis): """Generate a concise summary""" primary_category = content_analysis['primary_categories'][0] if content_analysis['primary_categories'] else "General content" main_objects = ', '.join(content_analysis['dominant_objects'][:2]) templates = [ f"This is a {primary_category} video that includes elements like {main_objects}.", f"The video presents a {primary_category} scenario, with its focus on {main_objects}.", f"The content centers on {primary_category}, highlighting elements such as {main_objects}." ] import random return random.choice(templates) def _generate_detailed_summary(self, description_text, content_analysis): # Use the summary model to generate a more detailed description. try: summary = self.summarizer( description_text, max_length=150, min_length=50, do_sample=False )[0]['summary_text'] return summary except Exception as e: # Failed to generate detailed information, switched to producing concise summary. return self._generate_concise_summary(content_analysis) def _generate_engaging_summary(self, content_analysis): """Generate an engaging summary""" primary_category = content_analysis['primary_categories'][0] if content_analysis['primary_categories'] else "Awesome" main_objects = '、'.join(content_analysis['dominant_objects'][:2]) engaging_templates = [ f" Don't miss out! This {primary_category} video takes you deep into the fascinating world of {main_objects}!", f" A spectacular showcase! A visual feast exploring the unique charm of {main_objects} in a {primary_category} setting!", f" Watch now! This video perfectly captures the {primary_category} moment of {main_objects}!" ] import random return random.choice(engaging_templates) class VideoSummarySystem: """Video Summary Generation System""" def __init__(self, model="./t5-small"): self.summary_generator = VideoSummaryGenerator(model) self.frame_descriptions = [] def accumulate(self, description: str) -> None: import json self.frame_descriptions.append(json.loads(description)) def finish(self) -> str: import json summary = self.summary_generator.generate_summary(self.frame_descriptions) result = { 'video_summary': summary, 'frames_analyzed': len(self.frame_descriptions), 'content_categories': list(set( cat for analysis in self.frame_descriptions for cat in analysis['content_type'] )), 'key_objects': list(set( obj for analysis in self.frame_descriptions for obj in analysis['key_objects'] ))[:8], 'processing_details': { 'total_frames': len(self.frame_descriptions), 'successful_analyses': len(self.frame_descriptions) } } return json.dumps(result) @property def aggregate_state(self) -> typing.Dict[str, typing.Any]: return { "frame_descriptions": self.frame_descriptions, } def merge(self, other_state: typing.Dict[str, typing.Any]) -> None: self.frame_descriptions += other_state.get("frame_descriptions") - 执行创建UDF和UDAF。
with create_connect() as conn: connset_function_staging_workspace( obs_directory_base=os.getenv("obs_directory_base"), obs_bucket_name=os.getenv("obs_bucket_name"), obs_server=os.getenv("obs_server"), access_key=os.getenv("access_key"), secret_key=os.getenv("secret_key")) print("finish set_function_staging_workspace") try: conn.delete_function("VideoContentAnalyzer", database=target_database) except Exception as e: print("UDF doesn't exists.") conn.create_scalar_function( VideoContentAnalyzer, database=target_database, packages=["transformers", "torch", "pillow"], imports=["./blip-image-captioning-base"] ) try: conn.delete_function("VideoSummarySystem", database=target_database) except Exception as e: print("UDF doesn't exists.") conn.create_agg_function( VideoSummarySystem, database=target_database, packages=["transformers", "torch"], imports=["./t5-small"] ) - 以aura_frame API形式使用Scalar UDF, UDAF,得到最后视频的摘要内容。 这里需要先将需要处理的视频文件上传到obs://xxxxx/xxxxx/(read_video_frames传入path参数)某一路径下,然后通过dataframe进行处理。如果视频不是mp4文件,还需根据文件类型在read_video_frames中的file_extensions中添加对应类型名称。
from aura_frame.multimodal.function import AggregateFnBuilder with create_connect() as conn: ds = conn.read_video_frames("obs://xxxxx/xxxxx/",image_height=800, image_width=400, image_format='jpg', include_paths=True, include_timestamp=True, file_extensions=["mp4"]) ds.show(limit=1) # use UDF udf = conn.get_function("VideoContentAnalyzer", database=target_database) ds = ds.map_batches( fn=udf, on=[ds.image["data"], ds.frame_index], as_col="descriptions", num_cpus=1, memory=1024, arch='x86', concurrency=1, model_name="./blip-image-captioning-base" ) ds.select_columns([ds.frame_index, ds.descriptions]).show(1) # use UDAF for summary udaf = conn.get_function("VideoSummarySystem", database=target_database) agg_builder = AggregateFnBuilder( fn=udaf, on=[ds.descriptions], as_col="describe", num_cpus=1, memory=1024, arch='x86' ) summary = ds.aggregate(agg_builder).execute() for row in summary.itertuples(): print(row[1])
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