I've written an HTML5 application that computes graphs at runtime and displays them in a canvas element.
I think that the answer to this question is probably "no", but I would like to know for sure if there is some way of programming my HTML5 application to take a series of these images and turn them into a video file, like an mpeg, for example.
In other words, I understand that HTML5 provides the video tag to embed videos in a web page, but can it be used to create videos at run-time?
The video element is play only (decoding)--it doesn't do encoding.
But...
If your user's browser supports WebM (modern versions of Chrome,Opera,FF,IE) then you can use WHAMMY to encode a .webm video file on the client-side. Here's a blog post by its creator, antimatter15:
http://antimatter15.com/wp/2012/08/whammy-a-real-time-javascript-webm-encoder/
Coincidentally, antimatter15 also created a client-side .gif encoder. If you are just stringing together a limited number of images you might consider an animated .gif instead of encoding a whole video. Here is antimatter15's code to copy a series of canvas drawings into an animated .gif:
https://github.com/antimatter15/jsgif
Good luck with your project!
Is it possible to convert WPF XAML (containing content such as image, video, animation etc) to HTML5 so that it can be rendered using html player on any device? Is there any readymade component/tool available to accomplish it?
If you want to use your code on the web, it would be best to use silverlight in my opinion.
How can I render PDF in HTML5 canvas?
I came up with pdf.js script https://github.com/mozilla/pdf.js. But its seems this project is still in development.
One solution may be:
http://googlesystem.blogspot.com/2009/09/embeddable-google-document-viewer.html
I want to create a html5 page with video and an image overlay - meaning some image that is showing over the video. This overlay will in time also be text in some cases. Is there any good way to achieve this?
What I've been trying this far is to use a <video> tag to hold the video, and draw the image into a canvas, which I place on top of the video. To show it I need to move the video back setting z-index to -1, but then the video controls won't work. Maybe there's a solution to make the controls work again, but I'm not sure if I'm on the right path here.. I am assuming there is a recommended solution to this. Maybe using a canvas which I fill both video and overlay into. Or something completely different?
Note: I edited the question as it originally pointed in the wrong direction regarding what was important here. I'd love to have a solution which makes this work seamlessly in fullscreen and everything, but the focus is: What is the appropriate way to place items on top of video - in html5?
Achieving what you want and have it supported in out-of-the-box fullscreen is problematic. Fullscreen support in html5 video is only optional and in any way not accesible thorugh the API (See discussion here).
Even if you used the built in fullscreen there is no way you could inject content above it unless you are willing to change the video file itself on the server in runtime.
what you can do however (And what I did in a similar case) is to implement your own video controls, run the video tag without the built in controls, and have fun with overlaying as many layers as you want on top of your now out of focus video.
As for fullscreen, you can implement some sort of custom background fullscreen similar to what's been done here
edit: The problem you're having by placing a canvas over the video is blocking the built in html video controls. My suggestion is to implement your own video controls (play, pause, volume, seeker, etc.) using html and javascript calling the video API. You can probably even make it prettier then the ugly built in controls.
Your controls can be contained in a layer above the overlaid canvas, and thus the video will be shown, above it the overlay and above it your control set.
You can read a little about implementing your own controls here or here
And anyway this can easily be much better than this.
Is there is PDF viewer which I can embed into my HTML and which I can style as I want.
Actually I need to show some page of PDF file and customize my own UI (few buttons to turn over the pages and commenting).
And if there is any Ruby solution (It's not actually about programming, as I understand) it will be great.
I want to show pdf because:
User can copy text
Text is in original layout
So I don't want to show it as images or as a converted text. But I want to show page in simple design. Without Flex or whatever.
Yes, it is possible, with HTML5!
https://github.com/mozilla/pdf.js/
This is a pure-javascript library that uses HTML5 functions to open a PDF file and render it in the page.
I successfully test the library in following browsers:
IE9 and current version of Google Chrome, Firefox, Safari
IE8 and lower do not support pdf.js (lacking HTML5 functions)
Usage
Include the javascript libraries in the HTML file and add an -element ( is HTML5 element, so it will work only in HTML5 browsers):
<body>
<canvas id="the-canvas" style="border:1px solid black;"/>
</body>
Use a javascript call similar to this to render the PDF inside this canvas:
PDFJS.getDocument('your-file-goes-here.pdf').then(function(pdf) {
pdf.getPage(1).then(function(page) {
var scale = 1.5;
var viewport = page.getViewport(scale);
var canvas = document.getElementById('the-canvas');
var context = canvas.getContext('2d');
canvas.height = viewport.height;
canvas.width = viewport.width;
var renderContext = {
canvasContext: context,
viewport: viewport
};
page.render(renderContext);
});
});
Other than a few browsers that have PDF viewers built in (Chrome comes to mind), PDF display is handled by external plugins, over which you have no control. You can't embed a PDF into a page, other than via iframes, and even then it's a completely external app from the browser, and not subject to css styling rules.
I don't see what Ruby has to do with this, as that'd be a server-side operation, and you're talking about client-side preparing. You could use Ruby (or most any other language) to extract the PDF's text, but you explicitly say you don't want to do that.
The closest thing to what you're asking would be Google Doc Viewer. It at least doesn't require anything more than JavaScript.
You could alternatively convert the PDF into HTML5 and display those pages using the PDF2HTML5 product by IDRSolutions. The output can be placed inside your own CMS and you can add your own GUI or you could use the existing options. You can have a look at potential output on the free converter and trial it if you like, it's a 100% Java library though which may or may not be a problem.
Note: For the sake of transparency it's worth mentioning I am currently a developer on said product so am very familiar with it's capabilities.
It's also worth noting pdf.js doesn't always perfectly match the actual pdf but it is very difficult to get an exact match and still preserve some of the key features you want. However it does do quite a good job most of the time.
The only thing that I know of that would help you do that is Adobe Flashpaper (there could be open source alternatives? Not sure).
http://www.adobe.com/products/flashpaper/
Examples here:
http://www.adobe.com/products/flashpaper/examples/
Considering compatibility, the best is to use a genuine adobe software for rendering pdf. Third party renderers work most of the times, but occasionally have trouble with some aspect of formatting. You can just download pdf reader from the adobe website, do a simple setting on the web browser, and let the browser open a pdf file using the genuine pdf renderer. At least on Firefox, you can do that.
If you want to progmatically display a pdf file without using a web browser, that means you need a GUI toolkit that works with a pdf renderer. All I know is poppler on ruby/gnome2. I once was able to use it with ruby 1.8, but since I have moved to ruby 1.9, I have not tried it. Other standard GUI toolkits for ruby are wxruby, fxruby, ruby/qt, shoes etc., but I am not sure which of them has a pdf renderer.
Sorry if not helpful.
No need for external libraries. Much browsers support already multiple ways to vies the pdfs. Like object, iframe, embed. You can use an object, with an iframe fallback, which in return fallbacks on a download:
<object data="/pdf/sample-3pp.pdf#page=2" type="application/pdf" height="100%" width="100%">
<iframe src="/pdf/sample-3pp.pdf#page=2" style="border: none;" height="100%" width="100%">
This browser does not support PDFs. Please download the PDF to view it: Download PDF
</iframe>
</object>
Source