This Python application allows users to download videos, audio, and thumbnails from YouTube. It utilizes the yt_dlp library to extract video details, select the desired format, and manage the download process.

• Python 3.x
• yt_dlp library

• Download video, audio, and thumbnails from YouTube.
• Choose quality for video and audio downloads.
• Use flags for automated download quality selection.
• Specify output directory for downloads.

1. Start the Application: Run the script to initiate the application.
2. Specify Output Directory: Enter the directory path for downloads or press Enter to use the current directory.
3. Select Flags (Optional): Use flags for automated quality selection:
   • best-v: Automatically selects the best video and audio quality for each link.
   • 1080p: Automatically selects 1080p video and best audio quality for each link. If there is no 1080p quality, selects the best video and audio quality.
   • 1440p: Automatically selects 1440p video and best audio quality for each link. If there is no 1440p quality, selects the best video and audio quality.
   • 2160p: Automatically selects 2160p video and best audio quality for each link. If there is no 2160p quality, selects the best video and audio quality.
   • best-a: Automatically selects the best audio quality.
   • thumbnail: Automatically downloads the thumbnail of the video.
   • Press Enter without inputting a flag to choose download options manually for each link.
4. Input Video URL: When prompted, enter the YouTube video URL.
5. Select Format: If no flags are used, choose from provided video and audio formats.
   • Video format selection also requires selecting an accompanying audio format.
   • Audio-only selection downloads only the audio.
   • Option available to download the video thumbnail.
6. Download: The selected content will be downloaded to the specified or current directory.

• Audio Only: Uncomment the postprocessor section in download_audio() to download audio exclusively in MP3 format.

• Checks for valid YouTube URLs and format selections.
• Displays messages for invalid inputs or errors.

• The application can process multiple downloads in one session, restarting after each download.