FLV Explained

FLV is a “Flash Live Video” file. It is a format that is designed for web playback, offering high rates of compression. Several products output in FLV format, including Sorenson Squeeze (The term “movie” often refers to common Flash source files (.FLA) and deployed files (.SWF) and is not synonymous with “video”).

The Flash Player browser plugin can play an FLV, but that FLV, must be either embedded in or linked to a SWF. That is, you can’t just put the actual FLV on an HTML page. You can however reference the FLV file using action script and SWF

Flash Media server and RTMP Streaming — Its been around for about 9 years now. In this system, a Flash application
communicates through the RTMP Server. Usually these applications enable person-to-person communication (one-to-many, or many-to-many). Flash may
also be used for machine-human communication, such as real-time data
transmission and notification.

Even though the browser can play the file while connected to the server,
there is no operating system player for the Flash FLV file format, so the file
cannot be played locally. Given the connection to the MX server however, it
allows the user to play the movie directly in their chosen browser. Flash MX Media
server can also administer time spent and pending usage as previously purchased
by the user.

Highlights of the Flash MX Server include the ability to provide your end
users with the best possible experience via a seamlessly integrated client that
lets you brand your broadcast the way you want to, with any devices containing
the Flash Player being capable of delivering movies when connected to the MX
Communications server or Media Server

Real Time Collaboration is a powerful programming model that will allow many
multiple connected users to share data and user interfaces in real time, coupled
with client and server data storage capabilities. Support for off-line usage in
addition to on-line usage allows the creation of robust applications that can be
used offline, and then synchronized automatically when the user goes back

The Flash Communication Server has functions for server-side scripts that may
disconnect users, authenticate, and control. Applications can be developed for
moderators or administrators to perform custom maintenance and monitoring.

The Macromedia Flash Communication Server works with multiple network
adapters on the server machine. This allows the server to be built for maximum
network throughput. In addition, “virtual hosts” may be configured on
each adapter. Virtual hosts can be used to isolate different server users,
allowing each server user to add applications freely while keeping their
programs separate from others.

A Fantastic File Format

The file format used in this process is Flash FLV or Flash Live Video, and it
plays in a Flash Player. While traditional methods of media delivery include
some kind of download to the user’s computer, either in a pre-loader or through
temporary Internet files, Flash MX Communications server and a Flash FLV Player
connect in a completely different manner. Simply put, it’s a new connection to
the file each time the user uses the controls in the player. This means that in
the background it’s a “start here” ? “stop here” ?
“start again here” style of play, with no downloads or caching.

Here’s The Top Ten Reasons to Stream Video Using Flash

1. FLV format file sizes after conversion are up to 60% smaller, saving
server storage costs.

2. FLV’s start – stop connection style saves on bandwidth (which is as much
as 60% less per month).

3. FLV format has no local player in operating systems, so file sharing is
virtually nullified.

4. FLV format plays directly in more browsers than Windows Media, Real Player
or QuickTime.

5. FLV server can authenticate clients, and control users as you wish.

6. FLV players can be completely customized for logos, branding and embedded

7. FLV players can play files from a programmable database, and simple
administration area.

8. FLV players can be programmed to integrate with databases for free
previews, time, users.

9. FLV encoding can include user information for content tracking, misuse, or

10. Flash Communications servers are easier to maintain than others, and less
prone to security hacks.

Who is using Flash Communication Servers? Yahoo, IBM, Sony, Universal
Studios, the list is growing. According to Computerworld’s “IBM to Drop
Windows-based Storage” article dated July 7th, 2003, “IBM plans to
discontinue its line of Windows-based network-attached storage (NAS) devices in
order to focus on higher-end products, including an upcoming file server that
will run Linux, sources said…”


Bandwidth: The total amount of data a network connection is capable of
sending through its system per second. This determines the length of time it
will take to transmit data.

Example: a file that takes 10 minutes to transmit across a modem with a
speed of 28,800 bits per second (bps) might take only one minute to transmit
over a DSL line because the DSL line has a larger bandwidth capability, which
can pass more bits through per second.

Buffering: Media players assimilate the incoming data and present it to
the viewer, as audio and/or video. During network congestion, this data is not
sufficient for the media player to continue playback and therefore, the player
must pause to receive more data before resuming playback. This process is called
“rebuffering”. To help avoid “rebuffering,” the media
players buffer a certain amount of data on reserve in the beginning before
playing the clip. Flash Communication (Media 2) Server eliminates this
“buffer” time.

Caching / Cache: Data that is frequently accessed is
often stored in the computer’s memory so that it may be re-accessed at a quicker
rate than if this data was stored on the computer’s hard disk drive. The process
of storing this data is called caching. The type of memory that stores this data
is called the cache.

Digital Rights Management: Refers to qualifying the
end-user prior to allowing the end-user to view or listen to the media file. It
is a term usually referring to the software that enables Internet ‘Pay-Per-View’

Digitizing and Encoding: Digitizing refers to the process
of capturing original media (film, video, sound recordings, etc.) into a digital
format onto your computer. Encoding refers to the process of converting this
digitized file into a streaming format.

ISP: Internet Service Provider. Companies that offer
access to the Internet to subscribers.

Latency: This is the delay of transmission of data.
Refers to the time it takes for a router, upon receiving the data, to determine
which router to forward the data to next.

Load-Balanced: A single computer is only able to transmit
a fixed amount of data. If the server receives too many requests for data at the
same time, a bottleneck forms causing a delay in transmission of data. Load
balancing refers to the process of grouping multiple servers together to act as
one single system This will minimize the risk of this type of delay.

MP3: Digital format specifically designed for music.

Network Congestion: Situation that occurs when the amount
of data being transmitted exceeds the capacity of the network. This results in
data transmission delays and possibly lost data. If a router becomes overloaded,
it will discard data as a last resort to manage the volume of data transmission.

Pay-Per-View: Just like pay-per-view events on
television, this refers to streaming media which viewers must pay to see.

Peering: An agreement between Internet backbone carriers
to exchange equal amounts of data at specified points along the Internet.
Peering agreements enable competing companies to utilize cable laid by one
another, thus reducing costs and duplication of cable routes. As the data is
exchanged freely between the carriers, there is no economic incentive for one
carrier to manage the incoming data of another carrier. Should one carrier
submit data in excess of the “peering” agreement, the other carrier
will usually discard the excess data. Peering connections on the Internet have
often been associated with bottlenecks of Internet data transmission.

QuickTime: Digital media software created by Apple

RealPlayer: Streaming media software created by
RealNetworks for the Internet.

Redundancy: Systematic approach to eliminating single
points-of-failure in a network or data storage system.

Router: A Router is a hardware device used throughout a
network that receives incoming data and determines the route for that data to
travel in order to reach its intended destination. A router is a switch with
built-in capabilities than enhance its functions and performance.

Scalability: The ability to expand capacity of an
existing data storage system or network without requiring replacement.

Streaming Media: Like television and radio for the
computer, streaming media technology converts other mediums (audio and video) to
digital formats that can be played back instantly by computers. It is comparable
to the process that enables one to turn on a TV set and instantly see a program,
or turn on a radio and instantly receive sound. The general term Streaming
incorporates all the formats created specifically for transmitting
audio, video and multimedia over the Internet.


Windows Media: Streaming media software created by
Microsoft. We do not offer Windows server space at the current time.

1) To play Flash files go to Get the latest Flash Player
and install the latest version of Flash Player.

2) Log in to your account at FLVHosting.com

3) Upload your FLV files onto the server by clicking on the folder name to login
and browsing to find the file on your computer and then clicking on upload.
After uploading is complete the file becomes available for streaming instantly.

4) Select a file or files for playback and click Generate Code.

5) Copy the code, and insert in the web page where you wish the movie to play.

Macromedia Flash Websites:

Video support in Macromedia Flash has continued to evolve since its
introduction in Flash MX and Flash Player 6. Flash Player 7 greatly improves
video quality, supports higher frame rates, and provides additional
opportunities for loading dynamic media at runtime.

At the core of Flash video is the Flash for Video (FLV) file format. FLV
files contain encoded audio and video data that is highly optimized (through the
use of Sorenson’s Spark codec) for delivery through the Flash Player. This keeps
the Flash Player footprint as small as possible by using a single video
rendering format.

Edited video content is encoded into the FLV format as it is imported into
the Flash authoring environment (or encoded into FLV format from third party
applications via the Flash Video Exporter plugin). Once imported into the Flash
authoring environment, FLV files can be converted to movie clips and can benefit
from all of the programmatic manipulations ActionScript has to offer, or
exported back out as standalone FLV files that can be invoked and streamed by
the Flash player.

On the delivery side, developers can choose from a variety of options for
embedding video into Flash movies or options for streaming external video files
at runtime, or options for exporting Flash video to other formats. Developers
need to carefully consider the types of video content, bandwidth, length, and
the level of user interaction needed before choosing a suitable delivery

In this TechNote we give an overview of the new video capabilities in Flash
MX 2004 and Flash MX Professional 2004 and discuss some of the different
strategies for incorporating and deploying Flash video.

Video capabilities in Flash MX

With the introduction of the Flash MX? platform, support for video has
improved with the addition of many new capabilities to the authoring and runtime
environment, giving developers more options for delivering embedded video and
progressive and streaming files. In short, developers have many new choices to
tailor the delivery method to best match the nature of differing video content
and ultimately to deliver the best possible user experience.

  • Video Import Wizard

    The wizard adds many new choices for encoding imported audio and video as
    well as providing basic clip scaling, cropping functions and contrast and
    brightness controls. 

  • Media Components

    a set of authoring components that enable connections to external video
    files and connections to Macromedia’s Flash Communication Server (available
    separately), and a new set of Behavior actions that work with Slides to
    accelerate and simplify the creation of advanced interactive video

  • Flash Video Exporter

    a new plug-in for use with third party applications that enables users to
    export Flash encoded audio and video directly from a third party authoring

Flash Websites

There are several alternative approaches to using video with a Macromedia
Flash-based website. The overriding factor in choosing the optimum method for
delivery is performance, which developers can best address by matching the
appropriate delivery mechanism with the actual content. For example, approaches
that work for short video clips embedded into a Flash movie will not work with
large video files that require external streaming. Likewise it is not efficient
to architect, code, deploy, and maintain an elaborate client-server delivery
mechanism when presenting short, highly-compressed and optimized clips.

Video content has its own set of considerations that developers must take
into account when applying optimal compression techniques which have an effect
on image quality and file size. Developers must consider all of these factors
and decide on what tradeoffs are acceptable when selecting the most appropriate
method for delivering video within the Flash player.

There are three distinct approaches for delivering video content with FlashMX
2004 and Flash Player 7:

  • Embedded FLV ? Video content is imported into the Flash
    authoring environment and embedded into the published SWF. 
  • External FLV ? Video content is remotely played from a
    host SWF containing a user interface and movie controls linking to the
    external file. Options include Progressive and Streaming FLV downloads to
    the Flash player. 
  • Exported FLV ? Content created in Flash is exported to
    QuickTime, AVI, or sequences of still frames for playback by other software.

Embedded SWF

Embedded SWF video is a straightforward method of delivering short video
clips and has been around since Flash Player 6. It is an easy to use, timeline
based technique and gives quick results. Video clips can be imported and encoded
into the Flash authoring environment. Playback is limited to simple play and
stop commands, and the video framerate must match that of the host movie, an
important consideration that will require authoring for the
lowest-common-denominator download speed.

For web delivery, content must be completely downloaded and must fit into
available memory on the user’s machine before playback can begin. The biggest
limitations to embedded video are movies having a maximum of 16,000 frames and
audio sync cannot be maintained beyond about two minutes. The entire video clip
must be published each time the movie is tested or previewed, which can lead to
lengthy authoring sessions.

Progressive FLV

Flash Player 7 introduced progressive download, a technique where external
FLV files are cached on the user’s local hard drive and played through the host
SWF at runtime with no limitation to the file’s size or duration. Audio and
video stays in sync and the frame rate is completely independent from that of
the movie host, enabling developers to create several versions of content
optimized for different download speeds. Since an external FLV is published
separately from the host FLA , authoring time is more efficient. For lengthy
audio/video content that requires fairly straightforward delivery, external
progressive FLVs can be a good choice.

The Flash MX Professional 2004 authoring environment contains Media
Components that can be used to quickly add FLV or audio MP3 playback control to
a Flash project. Media Components provide support for both progressive and
streaming FLV files.

Streaming FLV

Streaming FLV files have many of the same properties of Progressive FLV files
but are remotely served from Macromedia’s Flash Communication Server (available
as a separate product). This approach provides the most efficient delivery of
FLV and audio MP3 files by streaming data to the host SWF file and requires the
least hard disk and memory resources on the client end. Since data is not cached
locally on a user’s hard disk, this technique also provides the most secure
method of delivering media.

Macromedia’s Flash Communication (Media 2) Server has the ability to deliver
multiple simultaneous real-time communications, provides smarter delivery of
content by adjusting to the client’s connection speed, and has advanced
monitoring of traffic and throughput. For media projects that require the
greatest flexibility in efficiently handling the most complex data streams, this
is the best choice for delivery.

Exported FLV & QuickTime Flash Tracks

Flash can export movies to other formats such as Apple’s QuickTime or
Microsoft AVI. Flash can also export image sequences to a variety of formats,
such as GIF, PNG, JPG, AI and EPS.

Note: AVI export is only available in Flash for Windows.

QuickTime video can be imported into Flash where Flash tracks can be added
and exported back out as QuickTime and played with the QuickTime player or
plugin. This provides much of the Flash feature set, especially navigational
overlays and sprites, directly into a separate track within a QuickTime movie.
Another use is to use Flash to ?translate? graphics formats not supported by
QuickTime into QuickTime movies.

Note: QuickTime support for Flash is usually based on the
next-to-latest version of Flash. The current version of the QuickTime
Player? supports playback of Flash Player 5 SWF files. This is because
Apple’s development of QuickTime is not synchronous with Macromedia’s latest
Flash Player development. Also, it is up to the software developer to decide how
much of the Flash player feature set to include in its own players, so it is
likely that not all of the Flash player functionality will be present in all
software titles. This can limit the scope of ActionScript that can be carried
out on these titles. For details see Apple’s Developer Center article on QuickTime
6 support for Flash

The Flash Media Handler inside the QuickTime player supports an optimized
case for the alpha channel graphics mode, allowing a Flash track to be cleanly
composited over other tracks. QuickTime allows the SWF file format to execute
any of the standard Flash movieclip actions.


Coming soon, FLV Media Servers !