问题
It's strange, some MP4 files will play in HTML5, but others won't. Here is a test page http://psdtucss.com/test/test2.html, open it in Chrome 19.0.1084.46 m. The first MP4 plays, but the other one won't. What's the reason. The code is very simple:
<h3>the first mp4 file can play</h3>
<p><video width="640" height="264" controls="controls"><source src="1.mp4" type="video/mp4" />Your browser does not support the video tag.</video></p>
<h3>but the other can't play</h3>
<p><video width="640" height="264" controls="controls"><source src="2.mp4" type="video/mp4" />Your browser does not support the video tag.</video></p>
How can I fix this?
I tried videojs, but still some MP4 files won't play. Test page is here: http://psdtucss.com/test/test.html
回答1:
mp4 is only the container format. It may contain video and audio in a number of different codecs. Players (including those in a browser) need to support the container format and all of the used codecs in order to play a video properly.
Using VideoJS is definitely a good idea, it handles a lot of browser-specific workarounds for you.
However it does not solve one problem: There is no single video codec supported in all browsers. (See also Wikipedia: HTML5 video: Browser_support)
The practical solution probably is to provide two versions: h264 in a mp4 container and what is usually called webm (VP8 video and vorbis audio in a specific Matroska container). With those two you cover all major browsers.
For video conversion/recoding there are some tools and services available. I have no idea about your operating system or requirements. So just as a wild guess:
Something I used to help a friend publish a few videos on his little blog is this shell script using ffmpeg for conversion. It still leaves a lot of potential for improvement (in all of video quality, performance and coding) but should be good enough to get started.
回答2:
The first video uses h264 encoding which is supported by everything except Firefox and Opera. The second video uses the MPEG-4 video codec which is not supported by browsers. The only widely supported video codecs are Theora, H.264 and VP8.
MPEG-4 Part 2 video codec is different from the MPEG-4 Part 14 container format
回答3:
Your video 1.mp4 is encoded using h.264 but video 2.mp4 is not. get MediaInfo to check about it.
回答4:
MP4 supports multiple codecs. Some players don't support all codecs (some codes require licensing, or some codecs were released after the browser was written).
来源：https://stackoverflow.com/questions/11588654/why-wont-some-mp4-files-play-via-html5