I think I understand the WCAG 1.2.5 Audio Description (Prerecorded) rule, but what I can't find a straight answer on is if what if the per-recorded background video provides no real value, like if it's just a short video of someone walking on a loop with no talking/audio. Does this rule still apply?
Short Answer
Assuming the video serves no purpose other than decoration then you are safe to hide it with aria-hidden="true".
Longer Answer
While the above is perfectly valid for accessibility, there are other considerations from an accessibility perspective.
Do you provide a way to pause the video? If someone has an anxiety disorder then the video can be distracting so you must provide a way to pause the video. (or you could use the Prefers Reduced Motion media query and use that to stop the video auto playing, however the support is not fantastic at 80%.)
You should also add the muted attribute to indicate that the video has no sound to screen readers.
If the video does provide a purpose (i.e. it emphasises what the company does) then you should add a description to the video using aria-describedby and pointing that to a hidden <div> with a description of the video contents as a minimum.
Final Thoughts
If the video is purely decorative, has no meaning within the page and is there just to 'look cool' perhaps consider replacing it with an image. It will massively help your page load times and so can only help with conversions, video backgrounds hurt more than they help as they take focus away from your call to action.
Related
I am using AVFoundation to take pictures instead of UIImagePicker due to how customizable the user interface presented to the user can be. When using it the aspect ratio that the picture is saved as is the same as the iPhone's video feed. What I want to happen is to have the pictures saved in the same aspect ratio as normal pictures are.
The way that I am currently approaching this is to overlay a black bar in the excess preview display and then just crop the photo after saving it as an image.
However, this feels very crude. I assume that it is a common thing to use the AVFoundation as a way of taking photos and so I assume I must be missing something!
I have used this example code. And I have read through the AVFoundation documentation but can only assume that I am missing a function. I have also read through similar questions to this which describe the process by which I might go about cropping images, but that isn't really my concern.
On the other hand, if there is no standard way to do this, please do let me know so that I can stop worrying that I am approaching it in a convoluted way.
Also, I am using Objective-C so if answers contain code, please could you use the same language?
Good day,
I would like to take this opportunity to give my many thanks to the people of stackoverflow.com.
I have been new to coding, .net, over the past year, and I have always found stakoverflow to be a fantastic base of knowledge for learning. I spent the last couple weeks working, in depth, on a speech recognition project I am going to use with the upcoming release of Media Browser 3. Originally, the idea was to build a recognizer and have it control media. However as I moved through the different namespaces for speech recognition, it lead me into the realm of the Microsoft Kinect sensor. The more I use the kinect device, the more I would like to use some of the skeleton tracking it has to offer. Which leads me to my question.
I am not interested in build a WPF application that displays a window of what the kinect is seeing. This is part of a Form application, in which I would like to support only two of three gestures.
The idea is for it to watch for three gestures and simulate a key press on the keyboard.
So first I enable skeletonframe before the the audio for the recognizer, because I had read on here somewhere that enabling the skeleton after the audio canceled the audio for some reason.
Then I add some event handlers to my form.
I added skeletonFrameReady event.
I suppose my main questions would be, am I on the right track with skeleton tracking? Is it possible to do this from a form application without trying to draw th skeleton?
Thank you again,
I hope I made sense, sorry for my ignorance.
Ben
It is possible of course. For gesture recognition you can make a comparison between the positions of the joints (In the method that skeletonFrameReady event calls, which is called several times per second).
If you want to recognize complex gestures (like waving a hand), I suggest you take a look at this page http://blogs.msdn.com/b/mcsuksoldev/archive/2011/08/08/writing-a-gesture-service-with-the-kinect-for-windows-sdk.aspx and download the sample code there. (which is hidden in the last paragraph :)
Main idea is checking for predefined gesture segments with the correct order (If the segment1 is successful, look at segment2. If segment2 is paused, look at segment2 again until it is either successful or failed).
Hope this helps.
I am using HTML5 Canvas for rendering video, but the rendering is taking huge amount of CPU? I am using GtkLauncher (with webkit 1.8.0) for rendering the video on the Canvas.
Can some one please throw some light on this? Is video rendering on Canvas not efficient for embedded systems?
Also I would like to know, whether there is a way in HTML5 video tag to know the video frame rate, before I actually start to render the data on the Canvas. This I would need to know because I would have to set the timer (used for drawing the video frames) at that same frame rate .
Thanks and Regards,
Souvik
Most likely the video rendering is not accelerated and needs to
Decode on software
Resize on software
You did not give system details so this is just a guess. By poking browser internals you can dig out the truth.
Video framerate cannot be known beforehand and in theory can vary within one source. However if you host file yourself you can pre-extract this information using tools like ffmpeg and transfer the number in side-band (e.g. using AJAX / JSON).
My requirement is something like this.I have 1 youtube video url and i have to play audio of that particular URL instead of Video so is it possible in iPhone/iPad to play this kind of audio from video link?Please guide me.
I don't think you are allowed to by Youtubes terms of use; I am referring to the API terms. However, it is certainly technically possible. One hackie but simple solution would be to make an invisible view that plays the video; you would never see the video but you should be able to here the audio; just set the view's alpha low.
However, I do not recommend breaking the terms for the API, as I am sure there would be repercussions. Best of luck with your client.
I am working on a project where I would like to open a video (on a Mac) with QTKit. That part I can do no problem, but as I am playing it, I would like to edit or modify the video on the fly using OpenGL.
From what I understand, I should be able to intercept the frames and change them before it hits the display, but no matter what I do, I cannot seem to do so.
It sounds like you should have a look at Core Video and the display link mechanic.
You can basically get a callback on a high priority thread with the decoded frame in a CVImageBuffer and do whatever you like with it (including packing it up as a texture for OpenGL processing and display).
Apple provides documentation and demo code snippets on the developer sites.