Online video delivery experience
There are usually two different ways to do this when delivering an online video. HTTP Progressive Download or Streaming. You can assume that all the videos are playing, but you will be surprised to know that most are not.
So what are these two methods? How are they different? What are the advantages and disadvantages of both? Why would I want to use one method over another?
All web servers are progressive downloadable. This is just a video file method that is delivered to the browser via HTTP. It’s like a person downloading a file from your website. In fact, the video is delivered in the same way that your website has an image, CSS, JS, PDF, or other file.
The main difference is that the media player can start showing the video while downloading. For example, the FLV file provided by HTTP Progressive Download will start playing in your Flash Player as soon as it receives some data through the browser. The same goes for Windows Media Files. Instant Time will wait until the entire file is downloaded before the file is played, until QuickTime Player on PC / Mac is set for progressive play. So be careful when posting quicktime videos.
This is especially true when a video is being delivered via HTTP Progressive Download. As the video downloads, you’ll usually see a small status bar rising. You will not be able to move the Scrubber button before the amount has already been downloaded. This makes it impossible to jump to the end of the video before downloading this section. If you have a slow web server or limited bandwidth or the end user has a slow internet connection, then the user may take notice of the buffering.
Buffering occurs when the download cannot go beyond the video. The video will stop downloading further. If you pause the video and allow it to download a large portion, you can watch the video uninterrupted. In any case, this is a poor user experience when you consider using a CDN.
There is a technology called pseudo or streak stream. This method used TCP / IP range applications to allow the user to go to any part of the video. And the player will request a certain amount of file to download this part. This method is usually for FLV videos only and requires special services, or servers and custom Flash players to work.
When a video is delivered via HTTP, it is actually downloaded to the end user’s computer. This is good and bad. This is good because if the person watches the video again, it is already saved on their computer. This is bad because it makes it extremely easy for someone to steal your content.
Lastly, if someone watches only the first minute of your video but doesn’t stop downloading, the browser will download the entire file and you will pay for the delivery of the file even though the person has not seen the whole thing.
Streaming video requires access to a streaming media server. Some servers are Flash Media Server, Voza Media Server, Windows Media Server, Darwin Media Server (QuickTime), Real Media Server. These servers usually require a license and can cost several thousand dollars.
Some popular streaming protocols are RTMP, RTSP, and MMS.
When a video plays, it is sent to the end users’ computer via the UDP protocol. The user will have the ability to quickly forward or reverse the video. The video is not being downloaded to the end users’ computers, so it is unlikely that the content will be stolen. Also, if the user watches only 5 minutes in a 30 minute video, you only pay for the 5 minute delivery, not the whole video.
The biggest disadvantage of running on progressive downloads is that if a user watches the same video over and over again, you will pay for it every time. Videos are also streamed depending on what is encoded. Keep this in mind when making HD quality videos. 8 Mbps video sounds good and looks good, but most homes can’t maintain an 8 Mbps connection. If you have a really high high bit rate video, consider supplying via HTTP.
Streaming media servers will be available for use on most web hosting providers or content delivery networks (CDNs). Historically, providing Flash video has been more expensive than other formats. Prices have recently shrunk and you will know that its value in the supply of Flash or Windows Media files is approx. Is the same In the past I would have said that if your video is longer than 10 minutes, stream it and be less progressive. As prices have dropped, I would consider a video series of any length as the series generally starts to play faster than the progressives.
If you are considering using a service such as CDN or Cloud Computing and they say you can stream your videos, verify with their tech support that they are using a streaming server. And not just offering bandwidth.
If you are providing Flash videos you should provide RTMP or RTMPE protocol for streaming and HTTP for developers. Windows Media uses MMS or RTSP. QuietTime and RealMedia use RTSP.
I hope you find this article interesting. This is a great guide to help you decide whether to provide videos and use HTTP Progressive Downloads.
Top domain delivery networks that support streaming
* Light Light Networks
* Edgecast Networks
* CD Networks
* Level 3