A Python-based tool for downloading and reconstructing media from Microsoft Smooth Streaming (ISM) manifests. The project parses the manifest, retrieves media fragments, and rebuilds a valid MP4 file with proper PIFF headers and DRM-related metadata.

Features

Parses Smooth Streaming (ISM) manifests
Downloads and reconstructs video and audio tracks
Generates valid MP4/PIFF initialization segments
Supports DRM metadata (PlayReady / Widevine PSSH)
Automatic bitrate probing for better track selection
FPS detection from codec private data (AVC / HEVC)
Improved codec parsing and stream metadata accuracy
Interactive track selection

Requirements

Python 3.9+
requests
inquirer (optional, for interactive menu)
bitstring (required for advanced codec parsing)

Installation:

pip install requests inquirer bitstring

Usage

python ism_downloader.py

Then provide the manifest URL when prompted.

Notes

This project was developed primarily as a personal initiative to better understand Smooth Streaming (ISM) and MP4 structure. Some features were added to expand the scope of the project beyond its initial purpose.

Issues and Support

If you encounter any issues, please open an issue in the repository. I will try to provide support and maintain this project as time permits.

Acknowledgements

Thank you for your interest in this project.