When working with video files there are a wide range of different factors to consider and be aware of. One of the most important is the format you are working in. Knowing what format your footage is in can help you make some decisions regarding editing software and compression. When someone is talking about what format a video is in, they are typically wondering what container and codec the video is in.
What are Codecs and Containers?
A codec is the device or software that is used to compress or decompress digital media files like those used in video. When you are viewing or working with a file, the codec is responsible for playback, editing or transcoding. The codecs job is to organize the data in the media file.
Codecs are held within a container which is what is used to combine audio and video into a single file as well as containing metadata. When looking at a file name, the container is the .mov, .mp4, .avi or whatever extension is at the end. Some containers can only support certain codecs while others can support a wide variety of audio and video codecs. It's the containers job to let media players know to play both audio and video at the same time.
What are common Codecs?
There are hundreds of codecs that can be applied in different use cases. Below are a list of some of the most commonly used codecs and their purposes.
This codec is also referred to as MPEG-4 and is one of the most commonly used video codecs. It uses lossy compression and is widely supported in production, post and distribution. Many cameras record in this codec. It is the standard for most web video hosting and Blu-ray.
Red Digital Cinema uses their own codec for their cinema cameras. It produces high image quality compression with low loss. REDCODE is supported by many professional editing software. It uses the .r3d container.
Apple ProRes is a serious of both lossless and lossy compression codecs that were designed for intermediate post production work. ProRes is the replacement for the Apple Intermediate codec. ProRes is very popular as an acquisition codec and is widely supported by software companies.
This is Avid's lossy codec which was designed to work with their software. Similar to ProRes, camera manufacturers are starting to use the DNxHD codec.
Which Containers are most common?
Designed by Adobe, this container was made to be a standardized format for feature films. CinemaDNG can support uncompressed or compressed files. There are products that support this codec but the files tend to be very large.
The (.avi) container has the largest number of audio and video codecs of any container. This allows it to be supported by pretty much every editing software on the market.
The (.mov) container works on Linux, Windows and Apple workstations. It was designed by Apple but that doesn't limit its use to only Apple products or codecs. It comes with a large number of codec options.
This container was designed as an HD recording format by Sony and Panasonic and is typically used in camcorders. AVCHD uses a combination of H.264 and support for compressed or uncompressed audio. It is widely supported by editing software and uses the (.mts) or (.m2ts) extensions.
Which codec should you use?
Deciding which codec you should use should start with taking a look at the projects you are planning to work on as well as your hardware and software specs. Always choose a codec that will easily fit into your workflow even if it is not one of the more popular or common ones. The main benefit of using a popular codec is that there is more easily accessible information on how to work with it.