I'd like to load and play a smaller HEVC-encoded video on web browsers with support for it.
I'm using this code on Safari 11 (macOS 10.13), which has support for the HEVC format.
<video muted playsinline autoplay>
<source src="clip.webm" type="video/webm; codecs=vp9">
<source src="clip-hevc.mp4" type="video/mp4; codecs=hevc">
<source src="clip.mp4" type="video/mp4; codecs=avc1">
<p>Video not supported</p>
</video>
In Web Inspector > Network Panel, I see that Safari loads both clip.mp4
and clip-hevc.mp4
. If I inspect the video element, I see that clip.mp4
is playing, not clip-hevc.mp4
. I see the same thing on iOS 11.
When I call HTMLMediaElement.canPlayType()
on the types I specified, I get
maybe
onvideo/mp4; codecs=hevc
probably
onvideo/mp4; codecs=avc1
- Nothing on variants of the HEVC codec I've seen (e.g.,
hvc1
,hev1
)
Something else I noticed: When I remove the clip.mp4
option, clip-hevc.mp4
downloads and plays just fine!
How can I make sure that only the best supported MP4 variant downloads and plays in the browser?