Compression of Media Files
When it comes to hard drive space on your computer, few files, if any, come close to taking up as much space as music, pictures, and videos do.
The issues with these media files is that, not only is it difficult to store them all on to hard drives, but also the sending/transferring of these files becomes cumbersome. Sending files by shipping a physical storage space is expensive, email limits you on how large the files you can attach, and transferring with FTP (File Transfer Protocol) is time consuming. One of the best solutions to dealing with these issues is to simply compress the files into a more manageable size.
The technology behind compression is about reducing and/or eliminating redundant data and to use less bits than the original and since data contains a significant amount of redundancy, there is potentially a lot to cut down on. Nowadays. compression has become very important when it comes to data networks and cutting down their data usage and requirements.
When it comes to compression, the terms lossy and lossless will come up quite frequently. These two terms may end up greatly affecting the quality and size of whatever form of media files you are compressing. So it is very important to know what they are and their differences. A lossy compression means that the algorithms involved in the process do not take quality much into account when trying to achieve a smaller file size. It does not compromise in order to reach the end goal which is making a smaller file. A lossless compression, on the other hand, does not discard any information but rather finds more efficient methods to cut down file size without compromising the quality. This form of compression assumes that everything you put into it, you want out of it.
To decide which of these two types of compression to use, you have to ask yourself several questions: What type of media file am I dealing with? How small of a file do I want/need? What level of quality do I want/need? How much am I willing to compromise the quality in order to get a smaller file size? Images, for example, it is ok to use lossy compression in certain situations because the loss of information, typically, isn’t very discernible to the human eye. The certain situations in which lossy compression is ok is when dealing with personal pictures that were taken ourselves where minor quality loss does not really affect your viewing experience and takes up less room on your limited hard drive space. But images that are meant to be archived such as x-rays, comic books, blueprints, or any other situation where, if needed, can be reproduced to look exactly like the original picture, lossless compression is the way to go. Lossy cannot be used in situations where something needs to be recreated exactly like the way it originally was. As far as what file type to use for your images, again, it depends on the situation and personal opinion. If having a small file size is more important than maximum image quality, then use the lossy compressed JPG format. By no means am I saying that the JPG file format is not good but rather that there are higher quality file formats. If having a higher quality image is more important than file size, then the lossless TIFF format are your best bet. If you want a good medium between JPG and TIFF, then more compressed but still lossless, web-preferred PNG format is great.
With video, compression is similar to how it is with images. You can greatly reduce the file size without compromising on the visual quality by removing the redundant information in the frames of video. Essentially it is done by applying one algorithm on the original file/video to create a file that is ready to be stored/transmitted and an inverse algorithm to produce a video that shows the same content as the source material. The first algorithm that creates the ready file is called the encoder, while the inverse algorithm that produces a video that is the same as the source is called the decoder. Together, this pair of algorithms (encoder and decoder) working together is called a video codec. There are many different video codecs to use and choose from when it comes to compressing videos. But the only ones that you will mostly ever see (unless you go really in-depth and need one specific to your wants and needs) are MPEG-4 and H.264. Of these two video coding formats, H.264 is the better of the two. H.264 uses some innovative compression technology to both compress your videos into a small size but also deliver very clear video. H.264 has a several advantages over MPEG-4: 1) H.264 has a high compression rate which is between 1.5 to 2 times more efficient than MPEG. A higher compression rate means that it is possible to record more information on the same hard drive. 2) The video quality is better. 3) Playback is smoother with H.264 than with MPEG-4. 4) H.264 has a lower bit-rate which equates to better network transmission. Overall, H.264 is significantly better than MPEG-4. Not to say that MPEG-4 is a bad video compression format. Many programs only have the option of MPEG-4 video compression but if you were given a choice between MPEG-4 and H.264 compression formats, then H.264 is the way to go.
All of this talk of video codecs, lossy vs lossless, and MPEG-4 vs H.264 were all considered when dealing with any sort of media file that was used for DocuWrx. From the images on the website to the help videos in the program itself, lossless compression was used in order enhance the customer experience while still making a small enough file to make the process of navigating the website and product as efficient and smooth as possible.