Why Safari on iOS is not showing my HTML5 video poster?
I have this webpage:
http://healthpad.net/dashboard/
It have 10 <video> elements on it.
For some reason, when I load the page on an iPad, it is not showing the video posters.
Try the following:
- load the page on a desktop browser
- load it on an iPad or iPad simulator, and you get a big black box with a play button
please tell me why this is happening?
Here's what I've already ruled out:
Image Content-Type header.
I've validated that the image content-type header is properly set.
In the example above, the Content-Type header properly image/jpeg.
Interference with the video.js library
VideoJs is used to show that nice play button on desktop browsers and to customise the controls. This library doesn't interfere with the native player however.
Just to make sure, I've created a test video page which doesn't have the video-js class, so the library doesn't pick up and process that video. In fact, the test page doesn't even include any JS library, it's just
<html><body>
<video
controls
height="400"
width="600"
poster="http://healthpad.net/media/CACHE/images/uploads/video_poster_1414/bd5fba5a68ddd0f4b3f61193f6908962.jpg"
src="http://healthpad.net/media/uploads/video_processed_720p_1414.mp4"
></video>
</body></html>
http://healthpad.net/rj_templates/test/zzz/
Usage of any video attributes that may not be supported on Mobile Safari
The test page above just has a plain video tag. I've tried removing every other attribute except for src and poster, it didn't help.
Most of the StackOverflow questions on the topic just say "Restart your iPad"
Here's where it gets weird:
If you google around on this, the answers on StackOverflow that have been accepted often say "Restart your iPad, that did it for me".
So I've tried doing the same thing, at first I just said that it doesn't work in my case.
Then, I tried this:
(all of the following on the iPad simulator)
- Go to the site, video posters don't show
- Go to the test page (http://healthpad.net/rj_templates/test/zzz/), video poster doesn't show.
- Click home to exit Safari (or Cmd+Shift+H mac shortcut for the simulator)
- Double-Click home button to get the task switcher outside of Safari, tap and hold on the safari icon until the kill button shows.
- Kill Safari
- Open safari (restarted). At this point, if you load the test page (the one with just one video), the poster will show.
- Now go to the multi-video page: (http://healthpad.net/dashboard/). Video posters don't show.
- Go back to the single-video test page, the video poster for that one no longer works either.
- Repeat steps 3 to 8 to see the process of when video posters stop working.
So apparently, at some point, Mobile Safari decides it will no longer show any video posters. Also, apparently, my site triggers this condition.
Clarifications:
When posters no longer work, it doesn't only occur on one domain, no video posters will be loaded for any other site, regardless whether or not it's on a totally different domain (e.g. the demo video from http://www.videojs.com/).
In order to reset this behaviour, from what I've seen, you have to kill and restart Safari. Just closing and reopening it doesn't reset this state.
Does anyone have any idea why this is happening? Is there a way to work around it?
Answer
I got this working by using a PNG instead of a JPG.
Weird thing is, the JPG worked in iOS Safari locally (via a POW server on local wifi) but when pushed to staging the poster image didn't load. Both the local and staging code were referencing the same file on S3.
Changed the file format to PNG and it loads fine.