[FFmpeg-trac] #8349(avcodec:reopened): Dolby AC-4 Support

[FFmpeg]

#8349: Dolby AC-4 Support
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             Reporter:  Nomis101     |                    Owner:  (none)
                 Type:  enhancement  |                   Status:  reopened
             Priority:  wish         |                Component:  avcodec
              Version:  git-master   |               Resolution:
             Keywords:  ac4          |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
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Comment (by Jim Scarborough):

 This ticket is about ffmpeg support for Dolby AC-4. The primary motivation
 for ever so many people to be interested in this ticket is that ATSC 3.0
 mandates Dolby AC-4.  To that end, I suggest a policy workaround for
 people experiencing this issue:

 It is deeply problematic that **ATSC 3.0 mandates a proprietary codec**
 (Dolby AC-4) for audio on **free over-the-air (OTA) television** in the
 U.S. and other regions adopting the standard. This effectively **locks out
 open-source software** like FFmpeg, VLC, Plex, and Kodi, preventing the
 public from fully accessing broadcasts that are supposed to be free.

 == Why This Matters

 * Public airwaves should not be encumbered by proprietary restrictions.
 * FFmpeg and other open-source projects cannot legally implement AC-4
 support, limiting users' ability to watch ATSC 3.0 content.
 * The FCC approved ATSC 3.0 with no open alternative to AC-4, forcing
 consumers to buy Dolby-licensed hardware just to hear broadcasts.
 * If ATSC 1.0 is fully phased out, thousands (if not millions) of viewers
 may lose access to free OTA TV.

 == What Can We Do?
 This is not just a technical issue—it is a policy issue that affects media
 accessibility for everyone. If you believe that publicly available TV
 should not require proprietary codecs, consider:
 * Filing a complaint with the FCC (File here:
 https://consumercomplaints.fcc.gov/hc/en-us)
 * Contacting your local broadcasters to urge them to advocate for an open
 alternative to AC-4
 * Pressuring ATSC and the National Association of Broadcasters (NAB) to
 reconsider the forced use of proprietary codecs
   * ATSC: https://www.atsc.org/contact-us/
   * NAB: https://www.nab.org/about/contactus.asp
 * Spreading awareness on forums, tech news sites, and social media
   * AVS Forum: https://www.avsforum.com/threads/atsc-3-0-nextgen-
 tv.3125888/
   * r/Plex:
      *
 https://www.reddit.com/r/PleX/comments/jkx007/atsc_30_and_ac4_audio_support/
      *
 https://www.reddit.com/r/PleX/comments/11fmzcr/ac4_support_for_atsc_30/
   * r/HDHR:
 https://www.reddit.com/r/HDHR/comments/zqrr2o/atsc_30_compatability/
   * Silicondust:
     * ATSC 3.0 streams
 https://forum.silicondust.com/forum/viewtopic.php?start=45&t=79256
     * HDHomeRun 4k is Nextgen TV Certified:
 https://forum.silicondust.com/forum/viewtopic.php?start=165&t=78419

 == Thank you!
 🚀 **FFmpeg devs have done incredible work** supporting open media
 formats, and even coming up with an experimental solution here. But
 without an open AC-4 alternative, ATSC 3.0 will remain inaccessible to a
 large portion of its intended audience. Advocating for open standards
 isn’t just about software—it’s about **ensuring that publicly owned
 airwaves remain truly public**.

 I'd love to hear from you directly or in one of the online groups
 mentioned above. If anyone has legal, regulatory, or technical insights,
 let’s work together to **push for an open alternative**.
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/8349#comment:93>
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