Understanding Video Analysis Formats

tearIs there anything as frustrating as trying to open a video only for it not to work? You open your analysis software of choice but the video analysis format just isn’t supported. Below is an explanation of something that drives people mad and frankly is something that is hard to get your head around.

2 Parts to Video Analysis Formats

You need to think about your video format in 2 parts. Containers and Codecs. Containers are like shipping boxes while codecs are what’s actually inside.

What does a codec do?
Codec, which comes from COmpress DECompress uses some magic algorithms to make the original video smaller while keeping as much of the quality as possible.

Why do we need codecs?

We need to make the video smaller because uncompressed HD video runs at about 400GB per hour, making it almost impossible to share with anybody.

file-size-formatDoes compression mean we lose quality?

Yes, although there are some rare exceptions, in reality there is always a trade-off between size and quality. Some codecs are better than others at reducing the file size while maintaining a good level of quality. It’s all about picking the right one for your situation.

File Extension – Container

So let’s deal with this one first. At the end of all your video files you will see a file extension; something like .mov or .avchd. The file extension refers to the container the video is in. It actually gives us very little information about the video itself.

Here are some of the most popular Containers;

  • .AVI – very old container and doesn’t support H.264
  • .WMV – Very windows based and can be difficult to play on other devices
  • .Mov – Can use most codecs but still very MAC specific
  • .AVCHD – This was developed by Panasonic and Sony and was designed specifically for consumer electronics. If you have bought a camera recently you probably have this container.
  • .MP4 – This container can be used in most operating systems, handles H.264, works on mobile devices and is easy to upload to YouTube and Vimeo.

It’s very likely your videos are using one of these containers, with .MP4, .MOV and .AVCHD being the most popular.

File Codec

H264The amount of different codec’s is almost endless, hence why so many people find this all so confusing. I am going to just deal with 2 codecs and offer some general advice on how to manage your workflow.

  • MPEG-2, is the most common format for all DVD formats. If you rip a DVD it is likely to be an mpeg-2 codec.
  • Fastly becoming (if not already) the most popular codec is H.264 or you might also see it as mpeg-4. This offers the best balance between quality and file size and is the best format if you are uploading content to the web.

Encoding Video

So the problems can lie in the fact that we buy a camera that uses AVCHD container and some codec that isn’t workable with your current system. There are a number of ways to deal with this.

  1. If you are buying a new camera, try and find out what container and most importantly what codec the camera will produce. Double check with the software company if you are unsure.
  2. You can buy devices that encode the video as it records onto your laptop. However if you are not running the video live into your laptop this option isn’t best. But for those that do check out Blackmagic boxes or check with your analysis suppliers.
  3. It might be possible for you to work with whatever format the camera produces without any encoding. This way you only need to encode the videos until you need to share them. Depending on what you are using to distribute your videos – if it’s something like YouTube or Vimeo, they will convert the videos as you upload them. Also commercial packages like Dartfish and Replay Analysis have online video platforms that will take the raw footage and convert the videos to a usable format.
  4. Lastly you might need to download a video converter, these should allow you choose the original file and then choose a new format to export it as. This can take time and be a bit of pain, but it’s important so might just be unavoidable.

Anything To Add?

This is my understanding of Video formats and codec’s – if you have anything to add I would love to hear it.



Rob Carroll. Founder of The Video Analyst.com Performance Analyst. Always learning.