While MP4 is a universal container, it often relies on lossy compression. In the context of YouTube's itags, is a "video-only" DASH (Dynamic Adaptive Streaming over HTTP) format, meaning it must be combined with a separate audio stream itag (like 140 for AAC audio) to create a complete file. Get-EventSession.ps1 - GitHub
On YouTube, is an itag identifier for a specific video-only stream variant. This format is optimized for high-end viewing experiences: Resolution: Frame Rate: 60 frames per second (fps). Video Codec: VP9 (
Users can specifically request this format using command flags (e.g., -f 628 ) to target the 4K 60fps VP9 stream.
Often associated with Apple Native HLS (m3u8) delivery, though it represents the same quality as standard HTTPS streaming.
Technical communities on GitHub Gists maintain exhaustive lists of these IDs to track how YouTube and other platforms update their compression and delivery methods. 4. Comparison to Other Formats
