Compression Techniques

Compression is a very important part of super slow-motion video recording. Filming 10 seconds of footage at 100,000 fps will produce the same amount of data as over 9 hours of footage filmed at 30 fps. Without compression, the files created by slow-motion cameras would be nearly impossible to view. Luckily, there are many techniques that can be utilized to compress this data into a much more manageable size. Slow-motion video is created by filming at a very high frame rate, then playing it back at a normal frame-rate like 30 fps. Because of this, techniques such as frame dropping are not very useful because the viewer will be able to see any dropped frames. Typical video compression can be done to the footage produced by super slow-motion cameras, but due to the sheer amount of data this is very process intensive and typically cannot be done by the camera’s onboard computer. This causes two main issues: external compression and storage. Because the footage cannot be compressed by the camera as it is being filmed like typical cameras, it must be stored uncompressed. This causes the camera to use massive amounts of storage to hold the footage before it can be compressed by a more powerful computer. Typical operation of these super slow-motion cameras requires the camera to be connected to a computer with fast SSD storage by SDI cables. This limits the functionality of the cameras as they cannot be moved the same way that typical cinema cameras can be. Video compression can be done in a few different ways but all achieve the same goal; maximize quality while minimizing data. Strategies such as motion vectors and macro-block estimation are used in super slow-motion video compression.