As businesses have started to use videos more frequently, there is an increasing need to be able to compress videos. Sometimes more compressed versions of videos are required for various reasons, such as when storage capacity is an issue, to conserve bandwidth, to cater to email attachment limitations, and so on.
If you’re unfamiliar with video compression it can appear complicated on the surface. More importantly, if you don’t have a thorough understanding and you compress a video you’re unlikely to be satisfied with the results.
Instead, if you want to compress your business videos to any file size – you first need to understand a bit more about the factors that affect it.
Video Codecs: The Key To Compression
The video codec is a part of its format that contains an encoder and decoder. The encoder is responsible for compressing the video data to reduce its overall file size, while the decoder recreates an approximation of the video when it needs to be played.
In short, the video codec is what determines the compression that is used on the video data, which is why it also determines the compression rate. Because of that as codecs have improved and use more efficient compression algorithms, they are able to reduce the file size further while maintaining the same quality of video.
A good example of this can be seen by comparing H.264 and H.265 (also known as HEVC). The H.264 codec is the most widely-used codec currently and can compress video files quite well. However its successor H.265 can take a H.264 video and reduce it to half of its file size without affecting the overall video quality.
Needless to say this has major implications for your business videos, as it means transcoding to newer codecs could help you to compress and reduce the file size of your videos. However, if you do this you should take into account two factors:
Newer codecs tend to not be as widely-supported as older codecs and some devices and platforms may struggle or simply not be able to play them.
Although a newer codec can reduce the file size of the video due to its increased efficiency, it can only do so up to a certain point. In many cases, you may find that the resulting file size is still too large for your needs.
Simply put although the codec is the key to compression, it is not the complete answer if you want to compress your business videos to any file size.
Understanding the Video Bitrate
The other part of the equation when it comes to compressing videos is the video bitrate, which is quite literally the amount of data the video uses each second. It is directly related to the file size, seeing as the video file size is basically its bitrate multiplied by its duration (in seconds).
Suffice to say you can reduce the file size of your video by reducing the bitrate. However, that will affect its quality.
Every video requires a certain bitrate in order for it to be displayed without compromising its quality. That bitrate is normally based on the:
Different codecs require different amounts of data, as indicated previously. Newer codecs with more efficient compression require less data, which is why their file size is smaller for the same quality of video.
A video with higher resolution requires more data to be reproduced. For example, if two videos are both stored in MP4 with H.264 and have a framerate of 30, the one in 1080p would require a video bitrate of 8 to 10 Mbps, whereas the one in 4K would require a video bitrate of 35 to 45 Mbps.
The more frames there are in each second of video, the more data will be required. For example, a 1080p video at 30 frames per second in MP4 with H.264 may require a video bitrate of 8 to 10 Mbps. On the other hand, a video with the same resolution and format at 60 frames per second would require 12 to 15 Mbps.
While understanding these factors are valuable as guidelines when adjusting your bitrate, it is inadvisable to reduce the frame rate or resolution. Instead, they will give you an idea of what to expect and how far you can reduce the bitrate before the quality becomes an issue.
Balancing Quality and Compression
Assuming you do need to reduce the bitrate much lower than is required by the video, it then becomes a question of balancing the video quality against its compression.
The best approach is to gradually reduce the bitrate and observe its impact on the video quality. As you do you’ll notice that various types of compression artifacts start to appear.
It is up to you to evaluate at what point you’ve reduced the file size enough while maintaining an adequate quality for your business videos. In some cases you may even find that isn’t possible – for example you could technically reduce a video down to 1 MB, but it may be completely unwatchable because its quality is so bad.
At the end of the day, however, this method should let you compress your videos to any file size – especially if you also optimize its codec.
By now you should have a decent understanding of compression and how it works. All that you need to do to put it into practice is get your hands on software that can be used as an MOV to MP4 converter or to transcode your videos to other codecs. It should also allow you to adjust the video bitrate if need be.
Make no mistake your first few attempts at compressing videos may not be satisfactory, but you should be able to identify the root cause of any problems you encounter. All said and done you should be able to compress your business videos to any file size that you require – within realistic limits.