This simple-to-use mini guide lays down the fundamentals of encoding and compressing HD footage for the web to help editors/DV directors work quicker and produce a more streamline output.
The goal to producing web films is to create footage that looks good but is watchable by the mainstream user without the video sticking or taking an age to download.
Most video-makers do not have the same compression armory as the big online players like Apple and Google so the suggestions are based on equipment and software readily available to the average person.
Looking at the big picture the main issue is balancing the most important elements to achieve a winning solution.
This basically boils down to a compromise of 3 things:
COMPATIBILITY V BEST QUALITY V SMALL FILE SIZE
Let’s look at each one of these areas in more detail with tools and tips to achieve a video that looks great and plays smoothly.
Flash video is generally considered to be the leading online video format. Windows (WMV) is a close second, but Flash video is the winner for a number of reasons:
The Flash player is installed on a higher percentage of end user computers than any other video format. Although not all end users have the latest version installed (so they may not support the latest Flash video codec), Flash still enjoys the best overall support. And as more consumer sites continue to move to the Flash video format, it’s even more likely that your audience will have an appropriate player
The Flash video format works well across PCs, Macs, Linux, etc. Flash files are very consistent in their playback. They also handle variable connection speeds pretty well. It’s nice to know that it will play well across varied platforms.
In general, the Flash video format is very good at playing as it streams down additional content. WMV Format, Quicktime and Real either require a streaming server to achieve the effect or do not do as good of a job. While they’ve improved, it still seams like these other technologies are behind in progressive download.
The Flash video format provides some very nice features for overlays and interactivity.
Which version of Flash?
I recommend always encoding to Flash 8. Flash 9 is better quality, but its still not as widespread. Nearly everybody has Flash 8, even your grandma.
Best quality input
Keep everything at the best quality throughout the edit stage – no compressing or exporting to another codec. If you’re using Final Cut Pro I would suggest exporting as a Quicktime movie and ticking the ‘self contained movie’ box and keeping the current settings. Some people talk about exporting using the Apple Prores 422 (HQ) codec, but for web video I think this is a step too far, and makes minimal difference. Here’s a screen grab of the FCP export settings:
Optimal Video dimensions and sizes
The next consideration is what physical size you want to reduce your video to. The original High Definition size is going to be either 1980×1080 or 1280×720 as below:
Ideally everyone would love to show their video at this full size, but broadband speeds are still not fast enough to cope with the data transfer. It may play OK on your 10MB fiber optic connection, but you need to remember the number of offices that have just moved up to broadband, and the poor experience they would have at this size.
Hence, the video needs to be proportionately reduced to a more manageable size. This size changes year to year but the optimal size we have found is 512 x 288. 320 x 240 used to be the norm a few years ago, but this is a little small (and it’s only 4:3) to see good detail in a video.
512 x 288 is creeping up towards SD TV size (720×576 PAL) and works well on most PC screens/browsers. Actual size is below:
For the best image quality and playback, you should always use width and height dimensions that use a multiple of 4 (good), 8 (better), or 16 (best). Refer to the following tables to pick dimensions for your layout (Courtesy of influx):
This is a big one and determines the quality but also the size of the file – this can range from 300 to 6000 Kpbs. Taking on board current PC users connection speeds (average 2Mb in Feb 2009) sticking to between 493- 800 Kpbs works smoothly.
A good little application to work your bitrate out is here is – Adobe – Flash application: Flash video (FLV) bitrate calculator
Key Frames Buffer
Set this to 30 – it is relatively low, but any higher you generally lose the quality – especially if there’s lots of pans and tilts in the footage.
This is an important factor and determines how much of the video is uploaded before it starts to play. Setting the buffer to 10 seconds gives users a chance to download a reasonable chunk of the film without waiting too long and clicking away from the video – any less and it starts to stutters and jumps as it tries to play immediately – give it some breathing space!
I use On2 Flix Pro for my encoding, I found it a very simple, intuitive and quick piece of software. It’s a bit pricey but well worth the money spent on it. Here’s a screen shot of the settings (taking on board all of the above):
I hope all of the above suggestions assist you in producing great looking, smooth web video. Have a play around and see what works for you, but the above settings have worked successfully for me and are a good starter for ten.
Any questions please leave a comment.