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H.264 is publicly available for free from ITU's website: https://www.itu.int/rec/T-REC-H.264 https://www.itu.int/rec/T-REC-H.264 It's annoying because multiple

H.264 is publicly available for free from ITU's website: https://www.itu.int/rec/T-REC-H.264 https://www.itu.int/rec/T-REC-H.264 It's annoying because multiple standards bodies all publish the same spec, which is why H.264 is also called "MPEG-4 Part 10" because the spec is part of the MPEG-4 spec published in ISO/IEC 14496 (part 10 for AVC). The ISO specs aren't free (a couple hundred USD for the AVC spec), which is the most annoying part. You can get the H.263/H.264/H.265 specs for free form ITU, which covers a lot of the details you need for writing an encoder/decoder. Unfortunately sometimes you need the ISO specs for other things related to these codecs (e.g., ISO BMFF stuff). (edit: I'm a dork and originally misread the comment as saying it was $10k for the H.264 spec, when parent meant the HDMI spec; I removed parts of my comment that were related to that misreading).

willglynn 6y ago
ISO/IEC 14496-10 is actually one of the free standards: https://standards.iso.org/ittf/PubliclyAvailableStandards/ https://standards.iso.org/ittf/PubliclyAvailableStandards/ Presumably this is because H.264 is public. Your complaint is well founded, though: if you've built an AVC codec using public documents you may be frustrated to learn that ISO/IEC 14496-14 (describing the MP4 file format) and ISO/IEC 14496-15 (describing the AVC elementary stream and how to encode it as an MP4) are not public. It's also worth noting that ISO removes public standards. You may find references to public standards, like the link at https://ffmpeg.org/doxygen/2.7/webmdashenc_8c_source.html https://ffmpeg.org/doxygen/2.7/webmdashenc_8c_source.html – but neither the linked ISO/IEC 23009-1:2014 nor any other version of the MPEG-DASH standard is available to the public at this time. Pay up!
- userbinator 6y ago
  You can of course find a lot of those paid standards in the usual places... ;-) IMHO the generally lax attitude towards IP is one of the reasons responsible for China's strong technological growth.

willglynn 6y ago

ISO/IEC 14496-10 is actually one of the free standards: https://standards.iso.org/ittf/PubliclyAvailableStandards/ https://standards.iso.org/ittf/PubliclyAvailableStandards/ Presumably this is because H.264 is public. Your complaint is well founded, though: if you've built an AVC codec using public documents you may be frustrated to learn that ISO/IEC 14496-14 (describing the MP4 file format) and ISO/IEC 14496-15 (describing the AVC elementary stream and how to encode it as an MP4) are not public. It's also worth noting that ISO removes public standards. You may find references to public standards, like the link at https://ffmpeg.org/doxygen/2.7/webmdashenc_8c_source.html https://ffmpeg.org/doxygen/2.7/webmdashenc_8c_source.html – but neither the linked ISO/IEC 23009-1:2014 nor any other version of the MPEG-DASH standard is available to the public at this time. Pay up!

userbinator 6y ago
You can of course find a lot of those paid standards in the usual places... ;-) IMHO the generally lax attitude towards IP is one of the reasons responsible for China's strong technological growth.