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Flash Video Encoders

With the release of Flash 8 and the switch to On2 VP6 as the preferred codec, many producers are facing the decision of which encoder to use for Flash video. We faced this decision ourselves in 2005. Having used the Sorenson Squeeze encoder with Flash MX we were keen to know which tool would continue to give us the best possible quality. Our choices were:
- The Macromedia (later Adobe) Flash Video Converter (www.macromedia.com/software/flash/flashpro)
- The On2 VP6 plugin for Sorenson Squeeze (www.sorensonmedia.com)
- Flix Pro, the encoder utility provided by On2 Technologies (www.on2.com)

There are also many other encoders on the market but these three appear to offer the best quality and reliability. If you are more concerned about budget than quality or features, try the free Super © Encoder.

Macromedia/Adobe Flash Video Converter

This is a separate application which comes bundled with Flash 8. It is the encoder that most people use simply because it entails no extra cost.

We found that the Flash encoder is very easy to use and produces good quality video in most cases. However it has the serious limitation of lacking 2-pass encoding. 2-pass encoding allows the application to analyse the video file before encoding it, resulting in higher-quality encoded video. 1-pass encoding can be adequate for video which is fairly consistent, but sudden changes such as cuts can take the application by surprise and result in unnecessarily poor quality shots.

Encoding settings in Flash Converter are adequate without being spectacular. You can control basic settings such as maximum data rate, keyframes and cropping, but there are no bells or whistles.

Cue points can be added and edited easily with The Flash 8 Video Converter.

We tried a variety of input files which had been created with different codecs and Flash 8 Video Converter handled them all (even files from our old Miro DC30).

Overall, the Flash 8 Video Converter is a good tool which is only let down by the lack of 2-pass encoding. Some people feel that this is not a serious issue but we believe that it is. In many of the tests we ran, the difference in image quality was significant.

Sorenson Squeeze

Although Sorenson Media no longer provides the main codec for Flash video, the Sorenson Squeeze application can be upgraded with a plugin to include the On2 VP6 codec. This effectively keeps Sorenson Squeeze current for Flash producers. Unfortunately the plugin costs about the same as the entire Flix application available from On2 Technologies, and no free trial is available so you have had to pay for the plugin just to test it. For this reason we decided to abandon Sorenson and try Flix (which does have a free trial).

It's worth noting that the Sorenson Spark codec does still have some advantages over On2 VP6, for example it requires less processing power for the end user. It is also compatible with Flash Player 7, whereas VP6 requires Flash Player 8. However we don't feel that the advantages are enough to warrant using this codec — On2 VP6 is clearly better quality.

If you already own Sorenson Squeeze, it will be slightly cheaper to purchase the VP6 plugin than to purchase Flix Pro. However if you are starting from scratch, it is quite a lot more expensive to buy both Sorenson Squeeze and the plugin.

At the time of writing (January 2006), a new version of Squeeze is due with a free upgrade for v4 users. The new version will include:
- Cue Points
- Metadata for FLV
- Linked FLV (now the default for swf) or embedded FLV
- A cross platform FLV player
- New Flash player templates/skins with documentation
- Cross platform, Windows and Mac
- The VP6 plugin sold separately or bundled

Sorenson Squeeze is a very nice program to use, with an excellent interface, lots of options and productive workflow.

NOTE (September 2006): I have just been alerted to this bog entry External Link which claims there is a limit to the number of files which can be encoded per month with Sorenson Squeeze. I recommend that you take this into consideration.

Flix Pro

Flix Pro is the flagship Flash encoding application provided by the company who makes the codec, so you would expect it to be at least equal quality to any other option. Certainly, the addition of 2-pass coding is a dramatic improvement over the Flash 8 Video Converter. Cue points are supported.

However it's not all good news. In a series of test clips we found that Flix did not cope well with clips that were created with older codecs. Frequently it claimed to have finished encoding but the resulting clip had no video. The same clips were processed by Flash 8 Video Converter without a problem.

The user interface is fairly ordinary. There are no serious problems but it's not as nice to use as either Flash 8 Video Converter or Sorenson Squeeze. We couldn't avoid the impression that this application is less mature than Sorenson Squeeze.

Despite the drawbacks, Flix Pro provides much better quality video than Flash 8 Video Converter.


The lack of 2-pass encoding makes Flash Media Encoder a poor choice for anyone wanting the best quality. On the other hand, lack of cue point support is an issue for both Flix and Sorenson. Both companies are moving to solve this issue — when they do, they will both be clearly ahead of Flash Media Encoder.

Sorenson Squeeze provides the best workflow and productivity, although at this stage we cannot vouch for the quality of the video. The price is slightly higher but this is probably justified.

Flix Pro provides excellent quality video and will be perfectly adequate for most users, but power-users may find the interface and limited options frustrating.