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• MP4 codec support in Chromium

  9 décembre 2015, par Staggan

  We have integrated Chromium Embedded Framework into our Windows game to allow us to render web pages from within our application, and everything works fine, except MP4 videos.

  I understand Chromium does not include this codec due to licensing issues, but can anyone provide details on how we can add support, even if we have to license a codec for it.

  All the information we can find seems to be old, and the functions referred to appear to be deprecated... so we are at a bit of a loss.

  All the video serving networks we have spoken to appear to serve MP4s.. so changing encoding does not seem to be an option.

  Any advice would be greatly appreciated.

  Thanks

• Saying Goodbye To Old Machines

  1er décembre 2014, par Multimedia Mike — General, powerpc, via

  I recently sent a few old machines off for recycling. Both had relevance to the early days of the FATE testing effort. As is my custom, I photographed them (poorly, of course).

  First, there’s the PowerPC-based Mac Mini I procured thanks to a Craigslist ad in late 2006. I had plans to develop automated FFmpeg building and testing and was already looking ahead toward testing multiple CPU architectures. Again, this was 2006 and PowerPC wasn’t completely on the outs yet– although Apple’s MacTel transition was in full swing, the entire new generation of video game consoles was based on PowerPC.

  
  

  

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  I remember trying to find a Mac Mini PPC on Craigslist. Many were to be found, but all asked more than the price of even a new Mac Mini Intel, always because the seller was leaving all of last year’s applications and perhaps including a monitor, neither of which I needed. Fortunately, I found this bare Mac Mini. Also fortunate was the fact that it was far easier to install Linux on it than the first PowerPC machine I owned.

  After FATE operation transitioned away from me, I still kept the machine in service as an edge server and automated backup machine. That is, until the hard drive failed on reboot one day. Thus, when it was finally time to recycle the computer, I felt it necessary to disassemble the machine and remove the hard drive for possible salvage and then for destruction.
  

  If you’ve ever attempted to upgrade or otherwise service this style of Mac Mini, you will no doubt recognize the pictured paint scraper tool as standard kit. I have had that tool since I first endeavored to upgrade the RAM to 1 GB from the standard 1/2 GB. Performing such activities on a Mac Mini is tedious, but only if you care about putting it back together afterwards.

  The next machine is a bit older. I put it together nearly a decade ago, early in 2005. This machine’s original duty was “download agent”– this would be more specifically called a BitTorrent machine in modern tech parlance. Back then, I placed it on someone else’s woefully underutilized home broadband connection (with their permission, of course) when I was too cheap to upgrade from dialup.

  
  

  

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  This is a small form factor system from VIA that was clearly designed with home theater PC (HTPC) use cases in mind. It has a VIA C3 x86-compatible CPU (according to my notes, Centaur VIA Samuel 2 stepping 03, flags : fpu de tsc msr cx8 mtrr pge mmx 3dnow) and 128 MB of RAM (initially ; I upgraded it to 512 MB some years later, just for the sake of doing it). And then there was the 120 GB PATA HD for all that downloaded goodness.

  
  

  

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  I have specific memories of a time when my main computer at home wasn’t working correctly for one reason or another. Instead, I logged into this machine remotely via SSH to make several optimizations and fixes on FFmpeg’s VP3/Theora video decoder, all from the terminal, without being able to see the decoded images with my own eyes (which is why I insist that even blind people could work on video codecs).

  By the time I got my own broadband, I had become inspired to attempt the automated build and test system for FFmpeg. This was the machine I used for prototyping early brainstorms of FATE. By the time I put a basic build/test system into place in early 2008, I had much faster computers that could build and test the project– obvious limitation of this machine is that it could take at least 1/2 hour to build the entire codebase, and that was the project from 8 years ago.

  So the machine got stuffed in a closet somewhere along the line. The next time I pulled it out was in 2010 when I wanted to toy with Dreamcast programming once more (the machine appears in one of the photos in this post). This was the only machine I still owned which still had an RS-232 serial port (I didn’t know much about USB serial converters yet), plus it still had a bunch of pre-compiled DC homebrew binaries (I was having trouble getting the toolchain to work right).

  The next time I dusted off this machine was late last year when I was trying some experiments with the Microsoft Xbox’s IDE drive (a photo in that post also shows the machine ; this thing shows up a lot on this blog). The VIA machine was the only machine I still owned which had 40-pin IDE connectors which was crucial to my experiment.

  At this point, I was trying to make the machine more useful which meant replacing the ancient Gentoo Linux distribution as well as simply interacting with it via a keyboard and mouse. I have a long Evernote entry documenting a comedy of errors revolving around this little box. The interaction troubles were due to the fact that I didn’t have any PS/2 keyboards left and I couldn’t make a USB keyboard work with it. Diego was able to explain that I needed to flip a bit in the BIOS to address this which worked. As for upgrading the OS, I tried numerous Linux distributions large and small, mostly focusing on the small. None worked. I eventually learned that, while I was trying to use i686 distributions, this machine did not actually qualify as an i686 CPU ; installations usually booted but failed because the default kernel required the cmov instruction. I was advised to try i386 distros instead. My notes don’t indicate whether I had any luck on this front before I gave up and moved on.

  I just made the connection that this VIA machine has two 40-pin IDE connectors which means that the thing was technically capable of supporting up to 4 IDE devices. Obviously, the computer couldn’t really accommodate that in terms of space or power. When I wanted to try installing a new OS, I needed take off the top and connect a rather bulky IDE CD-ROM drive. This computer’s casing was supposed to be able to support a slimline optical drive (perhaps like the type found in laptops), but I could never quite visualize how that was supposed to work, space-wise. When I disassembled the PowerPC Mac Mini, I realized I might be able to repurpose that machines optical drive for this computer. Obviously, I thought better of trying since both machines are off to the recycle pile.

  I would still like to work on the Xbox project a bit more, but I procured a different, unused, much more powerful yet still old computer that has a motherboard with 1 PATA connector in addition to 6 SATA connectors. If I ever get around to toying with Linux kernel development, this should be a much more appropriate platform to use.

  I thought about turning this machine into an old Windows XP (and lower, down to Windows 3.1) gaming platform ; the capabilities of the machine would probably be perfect for a huge portion of my Windows game collection. But I think the lack of an optical drive renders this idea intractable. External USB drives are likely out of the question since there is very little chance that this motherboard featured USB 2.0 (the specs don’t mention 2.0, so the USB ports are probably 1.1).

  So it is with fond memories that I send off both machines, sans hard drives, to the recycle pile. I’m still deciding on an appropriate course of action for failed hard drives, though.

• How to contribute to open source, for companies

  18 octobre 2010, par Dark Shikari — development, open source, x264

  I have seen many nigh-incomprehensible attempts by companies to contribute to open source projects, including x264. Developers are often simply boggled, wondering why the companies seem incapable of proper communication. The companies assume the developers are being unreceptive, while the developers assume the companies are being incompetent, idiotic, or malicious. Most of this seems to boil down to a basic lack of understanding of how open source works, resulting in a wide variety of misunderstandings. Accordingly, this post will cover the dos and don’ts of corporate contribution to open source.

  Do : contact the project using their preferred medium of communication.

  Most open source projects use public methods of communication, such as mailing lists and IRC. It’s not the end of the world if you mistakenly make contact with the wrong people or via the wrong medium, but be prepared to switch to the correct one once informed ! You may not be experienced using whatever form of communication the project uses, but if you refuse to communicate through proper channels, they will likely not be as inclined to assist you. Larger open source projects are often much like companies in that they have different parts to their organization with different roles. Don’t assume that everyone is a major developer !

  If you don’t know what to do, a good bet is often to just ask someone.

  Don’t : contact only one person.

  Open source projects are a communal effort. Major contributions are looked over by multiple developers and are often discussed by the community as a whole. Yet many companies tend to contact only a single person in lieu of dealing with the project proper. This has many flaws : to begin with, it forces a single developer (who isn’t paid by you) to act as your liaison, adding yet another layer between what you want and the people you want to talk to. Contribution to open source projects should not be a game of telephone.

  Of course, there are exceptions to this : sometimes a single developer is in charge of the entirety of some particular aspect of a project that you intend to contribute to, in which case this might not be so bad.

  Do : make clear exactly what it is you are contributing.

  Are you contributing code ? Development resources ? Money ? API documentation ? Make it as clear as possible, from the start ! How developers react, which developers get involved, and their expectations will depend heavily on what they think you are providing. Make sure their expectations match reality. Great confusion can result when they do not.

  This also applies in the reverse — if there’s something you need from the project, such as support or assistance with development of your patch, make that explicitly clear.

  Don’t : code dump.

  Code does not have intrinsic value : it is only useful as part of a working, living project. Most projects react very negatively to large “dumps” of code without associated human resources. That is, they expect you to work with them to finalize the code until it is ready to be committed. Of course, it’s better to work with the project from the start : this avoids the situation of writing 50,000 lines of code independently and then finding that half of it needs to be rewritten. Or, worse, writing an enormous amount of code only to find it completely unnecessary.

  Of course, the reverse option — keeping such code to yourself — is often even more costly, as it forces you to maintain the code instead of the official developers.

  Do : ignore trolls.

  As mentioned above, many projects use public communication methods — which, of course, allow anyone to communicate, by nature of being public. Not everyone on a project’s IRC or mailing list is necessarily qualified to officially represent the project. It is not too uncommon for a prospective corporate contributor to be turned off by the uninviting words of someone who isn’t even involved in the project due to assuming that they were. Make sure you’re dealing with the right people before making conclusions.

  Don’t : disappear.

  If you are going to try to be involved in a project, you need to stay in contact. We’ve had all too many companies who simply disappear after the initial introduction. Some tell us that we’ll need an NDA, then never provide it or send status updates. You may know why you’re not in contact — political issues at the company, product launch crunches, a nice vacation to the Bahamas — but we don’t ! If you disappear, we will assume that you gave up.

  Above all, don’t assume that being at a large successful company makes you immune to these problems. If anything, these problems seem to be the most common at the largest companies. I didn’t name any names in this post, but practically every single one of these rules has been violated at some point by companies looking to contribute to x264. In the larger scale of open source, these problems happen constantly. Don’t fall into the same traps that many other companies have.

  If you’re an open source developer reading this post, remember it next time you see a company acting seemingly nonsensically in an attempt to contribute : it’s quite possible they just don’t know what to do. And just because they’re doing it wrong doesn’t mean that it isn’t your responsibility to try to help them do it right.