You can do dozens, nay, scores of things with your videos, without ever having to open a graphical video-editing application. The same goes, believe or not, for video editing. That would work if you only had one file, but what would you do if you had a filesystem with hundreds of files scattered all over the place? You would never consider seriously trawling through every directory and subdirectory, opening each file in turn, and clicking through the search-and-replace process, would you? A Bash script using find and sed would be the way to go. Say you have to change every instance of 'Bill' in a 100-page text file to 'Gary.' Sure, you could use the search-and-replace feature in your text editor. How much better? Well, it makes stuff easier to batch process, for starters. The presets are as follows:įor the highest video quality with all 3 settings are as follows: $ ffmpeg -i input.mp4 -c:v libx264 -crf 0 -preset veryslow output.Below is the video associated with this article. The slower the preset the longer the computation time. Setting the preset will determine which encoding speed and compression ratio. In addition to the previous two, selecting a preset can also increase quality but will increase file size. $ ffmpeg -i input.mp4 -c:v libx264 -crf 18 output.mp4

According to the documentation, values between 17-28 are “virtually lossless” visually but technically not. The default value is 23 while 51 is the worst quality. The setting for a lossless output is 0, the lower the number the higher the quality but larger the file size. The H.264 codec can be set as seen in the example below: $ ffmpeg -i input.mp4 -c:v libx264 output.mp4Īnother useful command is setting the constant rate factor (-crf) a rate control mode. This assumes that your FFMPEG installation is configured with -enable-libx264. Libx264 is used entirely throughout this book. It is recommended that the H.264 aka libx264 encoder is used with most video formats. This is usually done to perform the filter quicker as the higher the quality, the longer the command completion time.Ĭompression can be avoided using recommended codecs and setting quality. This is one of the most asked questions on google about FFMPEG and for a good reason, by default automatic compression is added depending on the filter.

Ffmpeg filter complex