Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

ADTS and MP3 clashes #66

Open
Dclipsham opened this issue Jun 5, 2024 · 1 comment
Open

ADTS and MP3 clashes #66

Dclipsham opened this issue Jun 5, 2024 · 1 comment

Comments

@Dclipsham
Copy link
Contributor

The attached file is the output of a Real Audio -> MP3 migration, using FFMPEG (package ffmpeg-5.1.4-1.el9) using a super basic ffmpeg -i <inputfile.ra> <outputfile.mp3> command line conversion.

The file currently identifies as fmt/1812 ADTS, because there is an 0xFFF041 sequence within 2045 bytes of the ID3 tag, so it pattern matches Audio Data Transport Stream sig.2 variant, and fmt/1812 has priority over fmt/134 MP3. The fmt/1812 identification is a false positive and it should identify as fmt/134 MP3.

I don't have an immediate solution and am curious if @thorsted has any thoughts...?

fmt-404_RealAudio_44_mp3.zip

@thorsted
Copy link
Contributor

thorsted commented Jun 6, 2024

I believe this is not the first time, but it seems to be very rare. These two formats have many similarities. In fact I believe an ADTS can be an mpeg-2 stream. I am curious what others recommend. Output from "file" on this MP3:
fmt-404_RealAudio_44.mp3: Audio file with ID3 version 2.4.0, contains:
MPEG ADTS, layer III, v2.5, 24 kbps, 8 kHz, Monaural

These frame formats can be tricky. Can we add another sequence of the same frame pattern to the ADTS signatures to be more accurate?

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

No branches or pull requests

2 participants