Monday, April 30, 2012

Silverlight Smooth Streaming

For output, Silverlight Smooth Streaming creates the following file types:

*.ismv

MP4 container files that contain MP4 video fragments (and audio fragments if the video source also contains audio). Expression Encoder creates one .ismv file per bit rate, and the number of bit rates depends on the IIS Smooth Streaming preset that you select. For example, if you select a preset that specifies that the video be encoded using nine different bit rates, Expression Encoder creates nine .ismv files.

*.isma

MP4 container files that contain only audio fragments. If you encode an audio-only source, this is the file format that results. As with .ismv files, the number of .isma files that are created can vary depending on your output choice.

*.ism

An XML-based server manifest file that describes the available bit rates in the encoded presentation. A Smooth Streaming-enabled server uses this file.

*.ismc

An XML-based client manifest file that includes important information about the presentation, such as the available bit rates, the codecs that are used, and other information required by Smooth Streaming-compatible clients to view the presentation.

Thursday, April 26, 2012

Wednesday, April 11, 2012

HTTP pseudo streaming vs. HTTP adaptive streaming

HTTP pseudo streaming

Both MP4 and FLV videos can be played back with a mechanism called HTTP pseudo streaming. This mechanism allows your viewers to seek (aka "trick play") to not-yet downloaded parts of a video by referencing timescale in the file header. YouTube is an example site that offers this functionality.

HTTP pseudo streaming combines the advantages of straight HTTP "progressive download" (it passes any firewall, viewers on bad connections can simply wait for the download) with the ability to seek to non-downloaded parts. The drawbacks compared to RTSP/RTMP are its reduced security (HTTP is easier to sniff than RTMP) and long loading times when seeking in large videos (durations over 15 minutes).

HTTP adaptive streaming

HTTP pseudo streaming should not be confused with HTTP adaptive streaming. Pioneered by Apple for iOS, it uses master index files (.m3u8) and the segmented mpeg-4 files (.ts). Apple recommended 10-second segments at 30fps (300 frames each), per Apple Technical Note TN2224.
https://developer.apple.com/library/ios/#technotes/tn2010/tn2224.html 
With HTTP adaptive streaming, 5 different bitrates will output 30 segment (.ts) files per minute of video, so a 10-minute video will be 300 files. Because of this, you will probably want to encode each video to a separate destination directory to keep your server organized.

Monday, April 9, 2012

7561 Pro HTML5 Test




Embed code

<video controls width="640" height="480">
  <source src="http://www.pixelgoat.net/encoding/demos/7561_pro.mp4" type='video/mp4' />
  <source src="http://www.pixelgoat.net/encoding/demos/7561_pro.webm" type='video/webm' />
</video>

Thursday, April 5, 2012

Adobe Flash 2012 Edition