video_processing.py

import os
import cv2
from scenedetect import VideoManager, SceneManager
from scenedetect.detectors import ContentDetector
from moviepy.editor import VideoFileClip
from transformers import CLIPProcessor, CLIPModel
import torch
import yt_dlp
from PIL import Image
import uuid

device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
model = CLIPModel.from_pretrained("openai/clip-vit-base-patch32").to(device)
processor = CLIPProcessor.from_pretrained("openai/clip-vit-base-patch32")

def download_video(url):
    ydl_opts = {
        'format': 'bestvideo[height<=1440]+bestaudio/best[height<=1440]',
        'outtmpl': f'temp_videos/{uuid.uuid4()}_video.%(ext)s',
        'merge_output_format': 'mp4',
    }
    with yt_dlp.YoutubeDL(ydl_opts) as ydl:
        result = ydl.extract_info(url, download=True)
        video_filename = ydl.prepare_filename(result)
        safe_filename = sanitize_filename(video_filename)
        if os.path.exists(video_filename) and video_filename != safe_filename:
            os.rename(video_filename, safe_filename)
        return safe_filename

def sanitize_filename(filename):
    return "".join([c if c.isalnum() or c in " .-_()" else "_" for c in filename])

def find_scenes(video_path):
    video_manager = VideoManager([video_path])
    scene_manager = SceneManager()
    scene_manager.add_detector(ContentDetector(threshold=20))  # Adjusted threshold for finer segmentation
    video_manager.set_downscale_factor()
    video_manager.start()
    scene_manager.detect_scenes(frame_source=video_manager)
    scene_list = scene_manager.get_scene_list()
    video_manager.release()
    scenes = [(start.get_timecode(), end.get_timecode()) for start, end in scene_list]
    return scenes

def convert_timestamp_to_seconds(timestamp):
    h, m, s = map(float, timestamp.split(':'))
    return int(h) * 3600 + int(m) * 60 + s

def extract_frames(video_path, start_time, end_time):
    frames = []
    start_seconds = convert_timestamp_to_seconds(start_time)
    end_seconds = convert_timestamp_to_seconds(end_time)
    video_clip = VideoFileClip(video_path).subclip(start_seconds, end_seconds)
    # Extract more frames: every frame in the scene
    for frame_time in range(0, int(video_clip.duration * video_clip.fps), int(video_clip.fps / 5)):
        frame = video_clip.get_frame(frame_time / video_clip.fps)
        frames.append(frame)
    return frames

def analyze_scenes(video_path, scenes, description):
    scene_scores = []

    negative_descriptions = [
        "black screen",
        "Intro text for a video",
        "dark scene without much contrast",
        "No people are in this scene",
        "A still shot of natural scenery",
        "Still-camera shot of a person's face"
    ]

    # Tokenize and encode the description text
    text_inputs = processor(text=[description] + negative_descriptions, return_tensors="pt", padding=True).to(device)
    text_features = model.get_text_features(**text_inputs).detach()
    positive_feature, negative_features = text_features[0], text_features[1:]

    for scene_num, (start_time, end_time) in enumerate(scenes):
        frames = extract_frames(video_path, start_time, end_time)
        if not frames:
            print(f"Scene {scene_num + 1}: Start={start_time}, End={end_time} - No frames extracted")
            continue

        scene_prob = 0.0
        for frame in frames:
            image = Image.fromarray(frame[..., ::-1])
            image_input = processor(images=image, return_tensors="pt").to(device)
            with torch.no_grad():
                image_features = model.get_image_features(**image_input).detach()
                positive_similarity = torch.cosine_similarity(image_features, positive_feature.unsqueeze(0)).squeeze().item()
                negative_similarities = torch.cosine_similarity(image_features, negative_features).squeeze().mean().item()
                scene_prob += positive_similarity - negative_similarities

        scene_prob /= len(frames)
        scene_duration = convert_timestamp_to_seconds(end_time) - convert_timestamp_to_seconds(start_time)
        print(f"Scene {scene_num + 1}: Start={start_time}, End={end_time}, Probability={scene_prob}, Duration={scene_duration}")

        scene_scores.append((scene_prob, start_time, end_time, scene_duration))

    # Sort scenes by probability in descending order and select the top 5
    scene_scores.sort(reverse=True, key=lambda x: x[0])
    top_scenes = scene_scores[:5]

    # Find the longest scene among the top 5
    longest_scene = max(top_scenes, key=lambda x: x[3])

    if longest_scene:
        print(f"Longest Scene: Start={longest_scene[1]}, End={longest_scene[2]}, Probability={longest_scene[0]}, Duration={longest_scene[3]}")
    else:
        print("No suitable scene found")

    return longest_scene[1:3] if longest_scene else None

def extract_best_scene(video_path, scene):
    if scene is None:
        return None

    start_time, end_time = scene
    start_seconds = convert_timestamp_to_seconds(start_time)
    end_seconds = convert_timestamp_to_seconds(end_time)
    video_clip = VideoFileClip(video_path).subclip(start_seconds, end_seconds)
    return video_clip

def process_video(video_url, description):
    video_path = download_video(video_url)
    scenes = find_scenes(video_path)
    best_scene = analyze_scenes(video_path, scenes, description)
    final_clip = extract_best_scene(video_path, best_scene)

    if final_clip:
        output_dir = "output"
        os.makedirs(output_dir, exist_ok=True)
        final_clip_path = os.path.join(output_dir, f"{uuid.uuid4()}_final_clip.mp4")
        final_clip.write_videofile(final_clip_path, codec='libx264', audio_codec='aac')
        cleanup_temp_files()
        return final_clip_path
    return None

def cleanup_temp_files():
    temp_dir = 'temp_videos'
    if os.path.exists(temp_dir):
        for file in os.listdir(temp_dir):
            file_path = os.path.join(temp_dir, file)
            try:
                if os.path.isfile(file_path):
                    os.unlink(file_path)
            except Exception as e:
                print(f"Error: {e}")