I'm not sure what the current state is on Mac regarding support for H.264.

• bug 851290 - Use GStreamer on Mac for H.264/MP3/AAC playback (instead of AV Foundation)

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https://bugzilla.mozilla.org/page.cgi?id=etiquette.html

If you right-click or Ctrl+click the video, can you tell what player is being used? For example, QuickTime or Flash. If it just looks like an ordinary Firefox right-click menu, that may indicate that a native video player is being used.

It looks like WebM. If I am reading it right. Does that make sense?

WebM is a patent-free format that usually gives good results in Firefox. https://developer.mozilla.org/en-US/docs/HTML/Supported_media_formats#WebM

Does your video hosting site transcode videos into multiple formats? If so, it seems there was a serious loss of quality when they created the WebM version. Maybe the resolution is more than their software can handle??

That's a great question. I have put out emails to Kickstarter support and waiting to hear back.

That would make sense. But the KS website says you can upload videos up to 5GB and these files are like 300MB.

I did read that Kickstarter just started prioritizing HTML5 over Flash, but I don't know enough to know how to interpret that. KS also reccomends H.264 as the codec to use on a Mac. I don't see why Firefox would have trouble reading this....very confusing.

Thanks for taking the time to think about this!

RE: the mac - H.264 bug. I don't know enough to know how to interpret this data. But I thank you for your response.

Because there are patents on MPEG encoding, Firefox doesn't include the technology to decode the videos. Instead, it uses the facilities provided by the operating system or in some cases third party decoders. The bug, I think, relates to when MPEG decoding will be available on Mac.

So, if you are playing the video on Mac or some Linux systems, the built-in HTML5 video player may pass on playing the MPEG video and instead choose a different format, if the site is offering it. That could be how you are getting WebM video. Assuming this affects all Mac users, hopefully the site will have a solution for making the WebM look good.

Right. I had gleaned some of this information from blogs, but don't fully comprehend it. But I think I understand what you are saying.

I guess my question is, is there a way for me to work around this? Can I use a different format (not MPEG) and then Firefox will choose flash instead of WebM?

Maybe I can use M4V?

I thought the codec was the problem, but it sounds like you are saying the browser and the format are not communicating well...

I hope I articulating myself well. I am getting foggy and might have to pick this up in the morning.

Just to reiterate - this is only happening with a video I uploaded. All other video I watch online is totally fine. So it seems like I should be able to find the proper format/codec combination....

thanks again for your help

This is probably caused by the server offering you videos in WebM format because your Mac platform currently doesn't support H.264 in Firefox, so there is a fall back to other formats.

You could consider to disable WebM as a test to see what the server will send in that case by setting the media.webm.enabled pref to false on the about:config page.