m3u8 video downloader

This skill should be used when the user wants to download videos from M3U8 streaming URLs. It handles parsing M3U8 playlists (including nested multi-bitrate playlists), downloading TS segments with multi-threading, handling AES-128 encryption keys, and merging segments into MP4 files using ffmpeg. Triggers: download m3u8 video, download streaming video, m3u8 download, download video from URL, download ts segments, HLS video download.

Overview

Download videos from M3U8/HLS streaming URLs by parsing playlists, downloading TS segments with multi-threading, handling encrypted streams (AES-128), and merging all segments into a single MP4 file using ffmpeg.

Prerequisites

Before executing, ensure the following are available:

1. Python 3 with requests library installed: pip install requests
2. ffmpeg installed and added to system PATH (required for merging TS segments into MP4)
3. Network access to the M3U8 URL

Workflow

1. Understand the User's Request

Extract from the user:

• M3U8 URL: The streaming playlist URL (required)
• Output filename: Name for the saved MP4 file (required, without extension)
• Base64 key (optional): For encrypted streams that require a manually provided AES-128 decryption key

2. Prepare the Environment

• Copy scripts/M3u8Download.py to the working directory
• Ensure requests is installed in the Python environment
• Verify ffmpeg is accessible from the command line: ffmpeg -version

3. Execute the Download

Use the M3u8Download class from scripts/M3u8Download.py:

python

from M3u8Download import M3u8Download

M3u8Download(
    m3u8_url="<user_provided_url>",
    file_path="<output_name>",        # Without extension; TS temp dir and final MP4 use this name
    max_workers=64,                   # Concurrent download threads
    num_retries=10,                   # Retry count on download failure
    base64_key=None                   # Optional: base64-encoded AES-128 key for encrypted streams
)

Key Parameters

Parameter	Description
m3u8_url	M3U8 playlist URL or local file path
file_path	Base name for temp folder and output MP4 file
max_workers	Max concurrent download threads (default: 64)
num_retries	Download retry count on failure (default: 10)
base64_key	Optional base64-encoded decryption key for AES-128 encrypted streams

4. What Happens During Download

1. Parse M3U8: Fetches and parses the M3U8 playlist. If it is a master playlist (contains EXT-X-STREAM-INF), automatically follows the redirect to the media playlist.
2. Download key: If the playlist specifies EXT-X-KEY, the encryption key is downloaded (or uses the provided base64_key).
3. Download segments: All TS segments are downloaded concurrently with progress bar display.
4. Merge: ffmpeg merges all TS segments into a single MP4 file.
5. Cleanup: After verifying the MP4 file size matches the total TS size (within 10% tolerance), temporary TS files, key file, and M3U8 file are deleted automatically.

5. Handle Errors

• If ffmpeg is not found, inform the user to install it and add to PATH.
• If download fails due to network issues, the retry mechanism will attempt num_retries times.
• If the MP4 output size does not match the TS total size, temporary files are preserved for manual inspection.
• For encrypted streams without a provided key, the script attempts auto-download; if that fails, ask the user for the base64_key.

Scripts

scripts/M3u8Download.py

Main download script containing the M3u8Download class. This is the primary script to use for all M3U8 download operations.

Notes

• The script supports both URL-based and local file-based M3U8 inputs.
• Chinese filenames and paths are supported.
• On Windows, os.startfile() is used to open the output directory after download completes.
• Do NOT modify the source code in scripts/ - use it as-is.