Progressive and Streaming are two type of Video downloading.
“Most end users cannot tell the difference between the video delivered by progressive download and that delivered via a streaming download.It is not until user look very carefully at video player functions like how the navigation actually works (rewind and fast forward),that there is a difference.”
progressive download is Delivery of a video file over HTTP .it is bulk download of a video file to the end user’s computer.A temporary copy of the video file is stored on the local computer so that the viewer can watch the file over and over without having to download the file each time.server delivering the file does not know or care that video file is encoded at what rate;it simply pushes data to the host machine as quickly as it can. This can sometimes give the
illusion that the file is being streamed because playback can start as soon as enough of the file is available on the local machine. This obviously restricts the users from skipping to parts of the file that have not yet been downloaded.
HTTP operates over TCP which controls transport of the packets over the network. TCP is optimized for guarantee of delivery of packets,regardless of file format or size.If a packet is skipped during the transfer of a file, it will request a resend of that packet.Resend requests take time and bandwidth and could increase the load on the server. TCP is not designed for efficient real time delivery or careful bandwidth control, but for accurate and reliable delivery of every bit.
- Advancing is not possible unless it has been downloaded already
- HTTP protocol in use
- Less secure, content can be easily copied
- More bandwidth is used to downloaded video file
Streaming Downloading:- Streaming downloads are based on Streaming server delivery method in which the video is played as it is received. Streaming server is a piece of software which deals with video requests. streaming server opens a conversation with the local machine. There are two sides to this conversation, one is for transferring the video and the other is for control messages between the media player and the server.These control messages include commands such as ‘play’, ‘pause’, ‘stop’ and ‘seek’.
Streaming servers use a specific set of protocols to deliver streams, such as RTSP(Real time streaming protocol),RTMP(Real time messaging protocol) and MMS(Microsoft media services). These protocols are more suited to delivering video streams because they are more focussed with continuous delivery than they are with 100% accuracy.they do not resend missing packets but instead continue with the rest of the video file.
- Secures video content delivery via temporary video link
- begin video playback at any point of the video, or skip through the video as you see fit.This is very convenient for users.
- efficient use of bandwidth as you are only using bandwidth for part of the video that are actually watched.
- video file is not stored on the viewer’s computer,video data is played and then discarded by the media player. This lets you maintain more control over your content.
Situations in Which You Should Use Streaming Video:-
- Any live video broadcast
- Any long video content
- if it is important to make it difficult to save the video locally.
Complexity:- Progressive download is easier to setup, and requires no special server side software. If you have access to a web server, you have access to progressive download. Streaming requires special software which needs to be installed on the server.
Streaming requires additional hosting costs, either as a result of purchasing and managing the server software or from additional fees which must be paid to hosting provider.
If you are trying to reach viewers with slower connections and need the quality to be high, progressive download would be your best option. if you know that your viewers will all have a fast enough connection to view your video,then streaming would be best option.