Video and Media

Re: transparent background in a video possible?

rtwPhoenix — Sat, 13 Jun 2009 14:54:17 GMT

I love WowIVideo have always been a fan of this technology. You made it sound so simple to do. With all the alpha channel on sites these days you would of thought SL folks would of done this and adopted it to the media player as well. I see a lot of potential with SL but it always seems like something is missing I need to use. Maybe SL 3 will be a much better solution.

Nice job with WowIVideo

RTW

Re: transparent background in a video possible?

GearWorld — Thu, 14 May 2009 20:22:38 GMT

That's a good start

Re: transparent background in a video possible?

mscherotter — Thu, 14 May 2009 17:17:50 GMT

Here is a technique to do transparent video in Silverlight 3 with the new Pixel Shaders:

http://blogs.msdn.com/synergist/archive/2009/05/14/alpha-video-with-silverlight-3-pixel-shaders.aspx

http://code.msdn.microsoft.com/SL3ChromaKeyEffect

Michael

Re: transparent background in a video possible?

GearWorld — Tue, 05 May 2009 22:42:44 GMT

By the way, you have 2 FOR on your RED ARROW,
it's a very nice work indeed. Can't wait for Microsoft to incorporate an easy way in Encoder or any easy way to set a transparency on a video.

Re: transparent background in a video possible?

ggibson1 — Mon, 04 May 2009 16:57:41 GMT

If you go to www.wowivideo.com you will see a technology I made using Flash 8 and their built in video transparency.

1) We record the video with a green screen or blue screen.

2) Use an app like Sony Vegas or Adobe AfterEffects to chroma key and output as a MOV file.

3) We then use an app that converts the MOV with alpha channel to a FLV as well as compress and resizes it.

4) We just play the FLV on top of a web page.

I would have used SilverLight to do this in addition to Flash, but SilverLight video does not support it so I made a Flash version only.

Re: Re: transparent background in a video possible?

GearWorld — Sun, 01 Mar 2009 22:25:33 GMT

:) Whatever you call it, Making myself with a BLUE background behind me and having the video showing just me un my page whereever I put it, would be totaly awesome. Any news on that ?

What I don't know yet is that when your movie is done un Movie maker is that means when put on your page there will really have a transparent background ?

Does Encoder 2 have any feature easier to do than movie maker ?

Re: Re: transparent background in a video possible?

slyi — Mon, 13 Oct 2008 23:14:51 GMT

Not natively but did you see http://silverlight.net/forums/p/17230/71330.aspx#71330

Re: Re: transparent background in a video possible?

Magikos — Wed, 08 Oct 2008 11:34:37 GMT

If you watch the SciFi channel, and ever noticed the SciFi logo in the lower corner, or noticed characters from a show like Ghost Hunters walk onto the screen - that is the effect we need.

Using industry standard chromakey video.

Re: transparent background in a video possible?

loarabia — Wed, 08 Oct 2008 01:26:47 GMT

Silverlight today (1 or 2) does not support alpha channel video. Depending on what you are trying to do, there may be a workaround that could apply.

You may be able to apply an Opacity Mask if you need to mask out a constant section of video but obviously that will not work for the chroma-key scenarios outlined above.
You may be able to tweak the coloring in a video's background to match the page itself if you are trying to chroma-key something on the page. This of course does not satisfy all scenarios either although I have seen it work for a number of people.

The Silverlight team is listening to you requests here and I do understand the pain that not having a feature can cause (I've wanted this feature myself). However, there are hundreds of requests like this (maybe even thousands) and the team has to make choices based on the data and constraints we are given with each release (unless someone has a timemachine).

One of the things that helps us analyze requests like this is knowing a bit more about the scenario. In other words, not just "I want to chroma-key" but "I want to chroma-key to make a weather map display" or "I want to chroma-key so that a recording of a person can walk all around my website and show people how to use it".

Of course, after we understand what you are trying to do, then comes the questions of how are you trying to do it? Does the video have alpha premultiplied? Are you planning on doing an honest to goodness chroma-key which indicates that you'll do background subtraction with some form shader type code? Are you planning on passing in multiple videos and having the runtime automatically chromakey? etc.

Re: Re: Re: transparent background in a video possible?

Magikos — Thu, 25 Sep 2008 16:16:20 GMT

My project requires the use of green screen (alpha channel) video - I hope Silverlight has plans to compete with Flash on this. Currently our solution involves using flash components over Silverlight - not a desirable solutions. :(

Re: Re: transparent background in a video possible?

Brian Knapp — Mon, 14 Apr 2008 16:26:33 GMT

Merging the background of your project with the background of the video is a terrible and inefficient idea. Silverlight should be able to handle green/blue screen video without too much problem. Hell if it can do crazy transforms and full video alpha channels, it should be able to do chroma keying.

Re: transparent background in a video possible?

Gavin JW — Tue, 02 Oct 2007 13:54:56 GMT

Thanks Bill,

That certainly is an option, unfortunately we want to allow the image in the background to be dynamic so that it can be re-skinned by the client without having to use a video editing suite. Looks like we might have to stick to white back drops and be clever with our clipping paths.

Re: transparent background in a video possible?

Bill Reiss — Tue, 02 Oct 2007 12:34:42 GMT

The answer I got was to merge the background with the video in a video editing tool. In one of the MIX presentations, one slide said it would be available in 1.1, but it looks like it will be some time after the actual 1.1 release now.

Re: transparent background in a video possible?

Gavin JW — Tue, 02 Oct 2007 12:23:04 GMT

* triple bump *

I have a project coming up that requires this as well, does anyone have any more info or links about this?

Re: transparent background in a video possible?

Bower — Mon, 01 Oct 2007 02:56:17 GMT

*double bump*

I'm thinking about using video sprites and a chroma-key would be just the thing I need.