Why quicktime not playing mp4 files on mac and windows pc?

MPEG-4 HE AAC and vp09 refer to specific types of audio and video codecs commonly used in streaming media.

What is MPEG-4 HE AAC?

HE-AAC (High-Efficiency Advanced Audio Coding) is an audio codec that is an extension of the regular AAC format.

It’s designed to deliver high audio quality at low bitrates, making it popular in streaming (like YouTube or internet radio).

It’s also known as AAC+, and includes tools like Spectral Band Replication (SBR) to improve compression.

What is vp09?

vp09 is a video codec developed by Google, also known as VP9.

It is a successor to VP8 and an open-source competitor to H.265/HEVC.

VP9 is commonly used on YouTube and other web platforms to stream high-resolution videos efficiently.

Why QuickTime Player can't play mp4 on mac

1. Lack of native support:

QuickTime Player on Mac doesn't support VP9 (vp09) video codec natively.

It also may struggle with HE-AAC in certain MPEG-4 containers if the file isn’t formatted properly.

2. Format container incompatibility:

If the video is in a WebM or a non-standard MP4 container using vp09, QuickTime won’t recognize the stream correctly.