10 ms·

Cisco's Open Source H.264 Codec

182 points by pcl 13y ago

lawl 13y ago
It would be really cool if they provided predictable builds, then we could just compare the binary against a self-compiled binary and be sure tehre are no backdoors we can't see in the code. Sadly even truecrypt fails to provide that. So i guess we'll have to life with binary blobs no one knows what they're really doing.
- cfluffy 13y ago
  Hi, I'm one of the people working on the stuff Cisco open sourced and yes, it will be predictable and verifiable builds. We are working with some of the Mozilla folks to make sure we can do that.
  - cpeterso 13y ago
    How often do you expect new Cisco builds to be published? Will the releases be versioned so Firefox version X knows it will always install OpenH264 version Y from Cisco's binary blob server?
    - cfluffy 13y ago
      Open to suggestions but the current plan would be to make it match up roughly with the Firefox 6 week release cycle. Definitely versioned and fingerprinted such that Firefox can verify that Cisco did not compile in bad stuff.
atonse 13y ago
I'm genuinely curious --- how come nobody thought of doing this (being some kind of platinum member and just putting it out there for all to use) all these years during the fighting about h.264 vs the open web and yada yada? What Cisco did seems to have put an end to all those debates, and h.264 is available for all, with patents intact, etc.
- samspenc 13y ago
  It costs Cisco $6 million a year to do this. I wonder if any of the beneficiaries (Firefox, etc) are pitching in. That sounds like loose change, but probably stuck up in bureaucratic decision-making at anyone who thought of this before. ("Why are we spending $6 million a year to make it free for everyone else again?") EDIT/UPDATE: In the second paragraph, I was referring to other companies and why they didn't do this earlier. It clearly brings Cisco quite a bit of goodwill to do this, and to see more video flowing on the web.
  - pkaye 13y ago
    I doubt it costs Cisco anything extra because they probably need the distribution rights for other products they develop (for example WebEx.) Besides it a good PR benefit for them with minimal incremental cost.
    - cfluffy 13y ago
      It costs Cisco lots (I work at cisco) as we were not close to paying the 6.5 million cap before this. Mozilla has been contributing to the code and making sure the project runs well but not towards any MPEG-LA payments. There are probably a bunch of reasons Cisco did this but making interoperable video just work on the internet would be at the top of the list. That's good for Cisco and others.
  - indrax 13y ago
    Cisco benefits from video on the internet being a big thing.
- pslam 13y ago
  No, it hasn't put an end to debate at all. This is an ugly workaround and still requires Cisco to build binaries on your behalf. It's quite a stretch of "open" and certainly not "free" (not that it claims to be). There is still ongoing work to create a better, free standard.
  - 13y ago
crbnw00ts 13y ago
There sure are a lot of hard-coded numbers in that codebase. In many cases it's easy to figure out where the numbers came from, but in others, it's nearly inscrutable without a named constant or a comment or something. Here's one example: https://github.com/cisco/openh264/blob/master/codec/encoder/core/src/svc_base_layer_md.cpp#L1254 https://github.com/cisco/openh264/blob/master/codec/encoder/... Where does "15" come from? I suppose if I'd written a codec like this before, or if I stared at the code long enough, I could figure it out, but wouldn't it be better to use an enum or a #define?
- tetrep 13y ago
  while i'm sure there's many other examples, in that particular case it's just the maximum value of an unsigned 8 bit integer, as defined above on line 1252. it would be a bit better if it explicitly had a nice #define but recognizing the values of common powers of two (minus one) is a useful code reading skill.
  - josephlord 13y ago
    I think you mean 4bit.
- matthewmacleod 13y ago
  Huh. I don't think it's just you - that looks like some properly nasty code. Formatting is all over the place, lines are commented out, comments are useless and obviously wrong in places... I don't really speak C++ though, so maybe this is normal.
  - nly 13y ago
    It's not because it's C++... this is just really ugly code.
    - midas007 13y ago
      The good point is that other hacked together quasi-compatible implementations now have an "official" reference implementation to browse. It could be a lot worse... I've waded through uncommented OCaml to discover how a certain shall-go-unnamed commercial, non-restful XML API worked. Or, Cisco could've never open-sourced it.
Daiz 13y ago
>Constrained Baseline Profile up to Level 5.2 (4096x2304) Well, I wasn't expecting miracles from this, but constrained baseline profile only? That's very disappointing. Not only will this be unable to decode most of the H.264 content out there (web and otherwise), you could very likely get better results with VP8. If only they'd have endorsed something like libavcodec instead...
- leetrout 13y ago
  Seriously... So much for adaptive bit rate. Makes sense that Cisco would be using CBP after seeing this on Wikipedia: "this profile is most typically used in videoconferencing and mobile applications" http://en.wikipedia.org/wiki/H.264/MPEG-4_AVC#Profiles http://en.wikipedia.org/wiki/H.264/MPEG-4_AVC#Profiles
  - Daiz 13y ago
    >Makes sense that Cisco would be using CBP Yes, I can understand the encoder only supporting CBP - videoconferencing is the one thing that you really need encoding capabilities for in a browser. Anything else you can basically always encode offline and use x264 or whatever. The real shortcoming is the fact that the decoder is also limited to CBP - as I said, this makes it completely useless for decoding most H.264 video out there (which is either Main or High Profile, generally the latter if we're talking HD content), web or otherwise.
    - cfluffy 13y ago
      This codec is designed more for interactive video conferencing applications and is not really great for non interactive encoding of a movie for playback. The choice of CBP came from that is what the IETF is considering to specify for the WebRTC standards.
- deleted 13y ago
  [deleted]
- espadrine 13y ago
  The real challenge for Cisco is to play well with contributors. While initially, members of the project seemed to be from the same Cisco family, it looks welcoming: https://github.com/cisco/openh264/blame/master/CONTRIBUTORS https://github.com/cisco/openh264/blame/master/CONTRIBUTORS
est 13y ago
https://github.com/cisco/openh264/blob/master/CONTRIBUTORS https://github.com/cisco/openh264/blob/master/CONTRIBUTORS Contributors are 100% Chinese. Is this project make in Cisco China R&D?
- general_failure 13y ago
  Cullen Jennings is not chinese
  - est 13y ago
    Well, when I posted the comment it was like this https://github.com/cisco/openh264/blob/3747f562492ea301b84e3eae4fa8cae765d95ccb/CONTRIBUTORS https://github.com/cisco/openh264/blob/3747f562492ea301b84e3... view history here https://github.com/cisco/openh264/commits/master/CONTRIBUTORS https://github.com/cisco/openh264/commits/master/CONTRIBUTOR...
who8mylunch 13y ago
What about x264 hosted at VideoLAN: http://www.videolan.org/developers/x264.html http://www.videolan.org/developers/x264.html? It's open source and people have implemented tons of cool software tools with it.
- dpe82 13y ago
  The key here is Cisco is paying the patent royalties for anyone who uses their codec binaries - which will cost them $6.5m/year. They could do the same for x264, but it's probably legally safer to distribute an implementation they wrote themselves.
  - who8mylunch 13y ago
    Thanks for the classification. I was not aware of those costs.
  - cfluffy 13y ago
    If the x264 people think they can give x264 to Cisco under a license that we can compile it and distribute the binaries with no changes to our MPEG LA licensing agreements, tell them to get talk of me (fluffy@cisco.com) if they want to do this. I came to the conclusion Cisco could not do this without x264 giving us an appropriate license.
- Florin_Andrei 13y ago
  Works great. You can put 3 hours of 1080p24 content on a single layer DVD (4.4 GB) and it still looks great. And there's room left for a soundtrack too.
  - MrBuddyCasino 13y ago
    Well it looks ok, but lots of detail is lost, especially if the source is grainy. I usually don't bother and go for 720p, but when you need great quality, you need 8-12GB for 1080p.
    - 13y ago
alister 13y ago
The license is abundantly generous -- it essentially says, "do whatever you want, but don't hold Cisco responsible". But this isn't the whole story. There are also patents involved, and these are not mentioned in the LICENSE file. Cisco does explain the issue on a different website: "a team can choose to use the source code, in which case the team is responsible for paying all applicable license fees, or the team can use the binary module distributed by Cisco, in which case Cisco will cover the MPEG LA licensing fees [1]" (where MPEG LA, or MPEG Licensing Authority, is the organization that holds the patents and of which Cisco is a member) I think that most of the audience here seems to know all this. But it wasn't clear to me, and I think it probably wouldn't be obvious to many other readers. [1] http://www.openh264.org/faq.html http://www.openh264.org/faq.html
- _rmp_ 13y ago
  can anyone confirm that in order to avoid MPEG LA license fees for encoding (20$ per unit sold I think) I can not distribute Cisco's compiled encoder library with my software (even if I use the binary from Cisco's repository -when they make it available- instead of compiling it myself) and the only option would be to download it from my software at runtime as a plugin? are there any other options (the systems on which my software is going to be installed do not have internet access)?
  - mcpherrinm 13y ago
    That's right. This is a workaround for the MPEG LA license, and having the user download the binary right from Cisco is the only way to have Cisco pay for the license fees. Anything else and you've got to become a licensee.
    - ZeroGravitas 13y ago
      I don't think that's entirely true. There's plenty of other H.264 products that you can get without directly downloading them. Flash is a close analogy, they pay the flat fee and nearly every desktop in the world uses it. And while some people download Flash direct from Adobe's servers, other's get it indirectly, e.g. pre-installed on computers they buy, or by downloading an installer. And people build apps (including desktop apps) around that functionality. Cisco is mostly doing this to support WebRTC interoperability with their deployed hardware (which generally means internet access) so they may just be going for the simplest thing for them to do.

182 points by pcl 13y ago

lawl 13y ago

It would be really cool if they provided predictable builds, then we could just compare the binary against a self-compiled binary and be sure tehre are no backdoors we can't see in the code. Sadly even truecrypt fails to provide that. So i guess we'll have to life with binary blobs no one knows what they're really doing.

cfluffy 13y ago
Hi, I'm one of the people working on the stuff Cisco open sourced and yes, it will be predictable and verifiable builds. We are working with some of the Mozilla folks to make sure we can do that.
- cpeterso 13y ago
  How often do you expect new Cisco builds to be published? Will the releases be versioned so Firefox version X knows it will always install OpenH264 version Y from Cisco's binary blob server?
  - cfluffy 13y ago
    Open to suggestions but the current plan would be to make it match up roughly with the Firefox 6 week release cycle. Definitely versioned and fingerprinted such that Firefox can verify that Cisco did not compile in bad stuff.

atonse 13y ago

I'm genuinely curious --- how come nobody thought of doing this (being some kind of platinum member and just putting it out there for all to use) all these years during the fighting about h.264 vs the open web and yada yada? What Cisco did seems to have put an end to all those debates, and h.264 is available for all, with patents intact, etc.

samspenc 13y ago
It costs Cisco $6 million a year to do this. I wonder if any of the beneficiaries (Firefox, etc) are pitching in. That sounds like loose change, but probably stuck up in bureaucratic decision-making at anyone who thought of this before. ("Why are we spending $6 million a year to make it free for everyone else again?") EDIT/UPDATE: In the second paragraph, I was referring to other companies and why they didn't do this earlier. It clearly brings Cisco quite a bit of goodwill to do this, and to see more video flowing on the web.
- pkaye 13y ago
  I doubt it costs Cisco anything extra because they probably need the distribution rights for other products they develop (for example WebEx.) Besides it a good PR benefit for them with minimal incremental cost.
  - cfluffy 13y ago
    It costs Cisco lots (I work at cisco) as we were not close to paying the 6.5 million cap before this. Mozilla has been contributing to the code and making sure the project runs well but not towards any MPEG-LA payments. There are probably a bunch of reasons Cisco did this but making interoperable video just work on the internet would be at the top of the list. That's good for Cisco and others.
- indrax 13y ago
  Cisco benefits from video on the internet being a big thing.
pslam 13y ago
No, it hasn't put an end to debate at all. This is an ugly workaround and still requires Cisco to build binaries on your behalf. It's quite a stretch of "open" and certainly not "free" (not that it claims to be). There is still ongoing work to create a better, free standard.
- 13y ago

crbnw00ts 13y ago

There sure are a lot of hard-coded numbers in that codebase. In many cases it's easy to figure out where the numbers came from, but in others, it's nearly inscrutable without a named constant or a comment or something. Here's one example: https://github.com/cisco/openh264/blob/master/codec/encoder/core/src/svc_base_layer_md.cpp#L1254 https://github.com/cisco/openh264/blob/master/codec/encoder/... Where does "15" come from? I suppose if I'd written a codec like this before, or if I stared at the code long enough, I could figure it out, but wouldn't it be better to use an enum or a #define?

tetrep 13y ago
while i'm sure there's many other examples, in that particular case it's just the maximum value of an unsigned 8 bit integer, as defined above on line 1252. it would be a bit better if it explicitly had a nice #define but recognizing the values of common powers of two (minus one) is a useful code reading skill.
- josephlord 13y ago
  I think you mean 4bit.
matthewmacleod 13y ago
Huh. I don't think it's just you - that looks like some properly nasty code. Formatting is all over the place, lines are commented out, comments are useless and obviously wrong in places... I don't really speak C++ though, so maybe this is normal.
- nly 13y ago
  It's not because it's C++... this is just really ugly code.
  - midas007 13y ago
    The good point is that other hacked together quasi-compatible implementations now have an "official" reference implementation to browse. It could be a lot worse... I've waded through uncommented OCaml to discover how a certain shall-go-unnamed commercial, non-restful XML API worked. Or, Cisco could've never open-sourced it.

Daiz 13y ago

>Constrained Baseline Profile up to Level 5.2 (4096x2304) Well, I wasn't expecting miracles from this, but constrained baseline profile only? That's very disappointing. Not only will this be unable to decode most of the H.264 content out there (web and otherwise), you could very likely get better results with VP8. If only they'd have endorsed something like libavcodec instead...

leetrout 13y ago
Seriously... So much for adaptive bit rate. Makes sense that Cisco would be using CBP after seeing this on Wikipedia: "this profile is most typically used in videoconferencing and mobile applications" http://en.wikipedia.org/wiki/H.264/MPEG-4_AVC#Profiles http://en.wikipedia.org/wiki/H.264/MPEG-4_AVC#Profiles
- Daiz 13y ago
  >Makes sense that Cisco would be using CBP Yes, I can understand the encoder only supporting CBP - videoconferencing is the one thing that you really need encoding capabilities for in a browser. Anything else you can basically always encode offline and use x264 or whatever. The real shortcoming is the fact that the decoder is also limited to CBP - as I said, this makes it completely useless for decoding most H.264 video out there (which is either Main or High Profile, generally the latter if we're talking HD content), web or otherwise.
  - cfluffy 13y ago
    This codec is designed more for interactive video conferencing applications and is not really great for non interactive encoding of a movie for playback. The choice of CBP came from that is what the IETF is considering to specify for the WebRTC standards.
deleted 13y ago
[deleted]
espadrine 13y ago
The real challenge for Cisco is to play well with contributors. While initially, members of the project seemed to be from the same Cisco family, it looks welcoming: https://github.com/cisco/openh264/blame/master/CONTRIBUTORS https://github.com/cisco/openh264/blame/master/CONTRIBUTORS

est 13y ago

https://github.com/cisco/openh264/blob/master/CONTRIBUTORS https://github.com/cisco/openh264/blob/master/CONTRIBUTORS Contributors are 100% Chinese. Is this project make in Cisco China R&D?

general_failure 13y ago
Cullen Jennings is not chinese
- est 13y ago
  Well, when I posted the comment it was like this https://github.com/cisco/openh264/blob/3747f562492ea301b84e3eae4fa8cae765d95ccb/CONTRIBUTORS https://github.com/cisco/openh264/blob/3747f562492ea301b84e3... view history here https://github.com/cisco/openh264/commits/master/CONTRIBUTORS https://github.com/cisco/openh264/commits/master/CONTRIBUTOR...

who8mylunch 13y ago

What about x264 hosted at VideoLAN: http://www.videolan.org/developers/x264.html http://www.videolan.org/developers/x264.html? It's open source and people have implemented tons of cool software tools with it.

dpe82 13y ago
The key here is Cisco is paying the patent royalties for anyone who uses their codec binaries - which will cost them $6.5m/year. They could do the same for x264, but it's probably legally safer to distribute an implementation they wrote themselves.
- who8mylunch 13y ago
  Thanks for the classification. I was not aware of those costs.
- cfluffy 13y ago
  If the x264 people think they can give x264 to Cisco under a license that we can compile it and distribute the binaries with no changes to our MPEG LA licensing agreements, tell them to get talk of me (fluffy@cisco.com) if they want to do this. I came to the conclusion Cisco could not do this without x264 giving us an appropriate license.
Florin_Andrei 13y ago
Works great. You can put 3 hours of 1080p24 content on a single layer DVD (4.4 GB) and it still looks great. And there's room left for a soundtrack too.
- MrBuddyCasino 13y ago
  Well it looks ok, but lots of detail is lost, especially if the source is grainy. I usually don't bother and go for 720p, but when you need great quality, you need 8-12GB for 1080p.
  - 13y ago

alister 13y ago

The license is abundantly generous -- it essentially says, "do whatever you want, but don't hold Cisco responsible". But this isn't the whole story. There are also patents involved, and these are not mentioned in the LICENSE file. Cisco does explain the issue on a different website: "a team can choose to use the source code, in which case the team is responsible for paying all applicable license fees, or the team can use the binary module distributed by Cisco, in which case Cisco will cover the MPEG LA licensing fees [1]" (where MPEG LA, or MPEG Licensing Authority, is the organization that holds the patents and of which Cisco is a member) I think that most of the audience here seems to know all this. But it wasn't clear to me, and I think it probably wouldn't be obvious to many other readers. [1] http://www.openh264.org/faq.html http://www.openh264.org/faq.html

_rmp_ 13y ago
can anyone confirm that in order to avoid MPEG LA license fees for encoding (20$ per unit sold I think) I can not distribute Cisco's compiled encoder library with my software (even if I use the binary from Cisco's repository -when they make it available- instead of compiling it myself) and the only option would be to download it from my software at runtime as a plugin? are there any other options (the systems on which my software is going to be installed do not have internet access)?
- mcpherrinm 13y ago
  That's right. This is a workaround for the MPEG LA license, and having the user download the binary right from Cisco is the only way to have Cisco pay for the license fees. Anything else and you've got to become a licensee.
  - ZeroGravitas 13y ago
    I don't think that's entirely true. There's plenty of other H.264 products that you can get without directly downloading them. Flash is a close analogy, they pay the flat fee and nearly every desktop in the world uses it. And while some people download Flash direct from Adobe's servers, other's get it indirectly, e.g. pre-installed on computers they buy, or by downloading an installer. And people build apps (including desktop apps) around that functionality. Cisco is mostly doing this to support WebRTC interoperability with their deployed hardware (which generally means internet access) so they may just be going for the simplest thing for them to do.