"Chromium is the open source version of Google browser Chrome, but these two browsers have some subtle differences on Feature, such as the support of the HTML5 media format, CHROMIUM is less than Chrome. Say HTML5, most compared with HTML4 One of the meaningful improvements is to add video tag, you can play video directly on the web page without the need to install the plug-in, as for HTML5 Video Tag to support which types of video formats depend on the browser, the HTML5 video supported by each browser There are three main formats:
1) H.264, the container format is generally used by MP4, and the audio format is usually AAC, which is supported by Microsoft IE 9;
2) Theora, the container format uses OGG, the audio format is Vorbis, supported by Chrome and Chromium;
3) VP8, the container format uses webm, audio format is Vorbis, supported by Chrome and Chromium. VP8 / WEBM is a free open video format for Google, VP8 and THEORA are the same series of video coding techniques, which are derived from VP3.
Where H.264 is a patented video format, using H.264 needs to pay patents and obtain licenses to MPEG-LA, although there is currently no charge, it is not guaranteed to be free forever. It is also based on this reason, Google talents acquire ON2, developing VP8 technology, and launched a free open VP8 / WEBM format on this basis. According to Google's official statement, Chrome / Chromium will no longer support the patent format of H.264 in the future, only support for VP8 / WEBM's open video format.
At present, Chromium has not supported H.264, while Chrome is temporarily supporting H.264, which is the difference between the Chromium and Chrome mentioned in this article on the support type of HTML5 video format. In addition to H.264, Chrome supports two audio formats than Chromium: AAC and MP3.
Various mainstream browsers support comparison of HTML5 media formats You can see this article: http://en.wikipedia.org/wiki/html5_video. The difference between Chromium and Chrome on Feature You can see this article: http://code.google.com/p/chromium/wiki/chromiumbrowservsgooglechrome.
Although Google bosses H.264, the fact is that H.264 has become one of the most video formats used on the current network, and VP8 / Webm has not been popular, and it has not yet received support from chip manufacturers. Therefore, if we do secondary development based on open source Chromium, it may face a problem that needs to be resolved: H.264 video is not supported.
On Ubuntu, you can see this article: http://www.omgubuntu.co.uk/2010/11/get-chromium-on-ubuntu-phromium-on-ubuntu-chromium-on-ubuntu-phromium-on-ubuntu-phromium-on-ubuntu-cho-play -MP4-H-264-MP3-view-pdf-files-nativeLELY /.
On Windows, add H.264 to Chromium, one way is to install the WMP extension provided by Microsoft to Chrome, downloaded here: http://www.interoperabilitybridges.com/wmp-extension-for-chrome Of course not open source. After installing this Extension for Chromium, if you encounter the MP4 video in the H.264 format, Windows Media Player is called to play. In addition, have there any other way? This is the theme of this article to be discussed.
The audio and video decoding of Chrome and Chromium is supported by FFMPEG. It should be known if FFMPEG is known. In the Chromium Source Tree Third_Party folder, you can see there is ffmpeg, but strange is that FFMPEG's code does not participate in compilation when compiling the Chromium source code, but by third_party \ ffmpeg \ chromium \ \ a32 \ below 3 pre-compiled dynamic link libraries to provide Chromium:
AVCODEC-54.DLL
Avformat-54.dll
AVUTIL-51.DLL
As for how Chromium under Linux uses FFMPEG, it is unclear because the source code does not contain the precompiled FFMPEG shared library (.so) below Linux.
When Chromium starts, the three.dll will be loaded, and the specific code is the function initializemedialibrary in Media \ Base \ Media_Win.cc.
These three.dlls of FFMPEG are called when playing HTML5 videos in Chromium, and the specific code is in Media \ Filters \ FFMPEG_VIDEO_DECODER.CC.
What is the relationship between Third_PARTY \ FFMPEG \ in this. DLL with the source code? I don't know, anyway, Google does not provide compilation of this 3 .dll Visual Studio project file in Chromium. Since Chromium is open source, Ffmpeg is also an open source project, which should not be provided in the form of a pre-compiled binary library. In fact, FFMPEG uses GPL or LGPL LICENSE, whether does this practice of Google violate the principle of GPL / LGPL? Very worthy of doubt. The treium source in the Chromium source code may just be a scorpion, I suspect that chromium uses FFMPEG to actually be closed.
As for Chrome, according to the online statement "Since FFMPEG uses LGPL 2.1 license, Chrome is closed, so Google pointed out that Chrome does not use the FFmpeg library, but use local video audio (Windows may be Windows Media Player) "" Is the actual situation? I saw the three FFmpeg dynamic libraries that were also known as the Chrome installation path. I will find that Chrome can't play HTML5 video if I can't play the HTML5 video. It can be seen that Chrome is still using FFMPEG. To play video, at least I use of Chrome 20.0.1096.1 is like this.
Since Chrome also uses ffmpeg, I think of a question. What is the 3 in Chrome in Chrome? DLL with chromium? Try it, the result is as follows:
With Chrome's 3.dll instead of Chromium, the result of Chromium still could not play H.264, but can play OGG and webm, the situation is the same as that of the unused library; 3.DLL of Chromium instead of Chrome, resulting Chrome Can play OGG and WebM, can't play H.264.
This can be seen from this 3. DLL does not support H.264 decoding, from the library file size can also be seen in the 3.DLL of Chromium than similar version of Chrome, obviously cut off the H. 264 Decoded support. In fact, in the Chromium Source THIRD_PARTY \ FFMPEG \ Chromium \ Config \ FFMPEG configuration files such as Chrome, Chromium, you can see the macro configured macro configial in the H.264 decoder is defined in Chromium and Chromiumos in Chromium and Chromiumos. It is defined in Chrome and Chromeos.
It is necessary to explain that only version similar to Chrome and Chromium can replace these three .dll directly, for example, the Chrome version I use is 20.0.1096.1, the Chromium version is 20.0.1090.0, if the version is too big to replace the library, may not be Normal play video.
It seems that Chromium supports H.264 video. The first step is to let the FFmpeg library support H.264 decoding. In the case where there is no Visual Studio project file that cannot be recompiled to the FFMPEG library, you can use a similar version of Chrome. FFMPEG library replacement.
The next step is to let Chromium support H.264 video when parsing the HTML5 webpage. It is exactly that it can identify the video source of the MIME type "" VIDEO / MP4 "" in the web page, just like the page below. It is in the CHROMIUM. MIME types not supported:
