Video compression is a crucial aspect of media production, especially when dealing with large video files. It helps reduce the file size without compromising on its quality. In this tutorial, we will explore how to compress a video using FFmpeg while retaining its quality.
What is FFmpeg?
FFmpeg is a free and open-source software that allows users to record, convert, and stream audio and video files. It supports a wide range of multimedia formats and codecs, making it an ideal tool for media production tasks.
Step 1: Install FFmpeg
Before we get started with compressing our videos, we need to ensure that FFmpeg is installed on our system. The installation process may vary depending on your operating system. You can visit the official FFmpeg website for instructions on how to install it on your system.
Step 2: Check Input Video Properties
To compress a video successfully, we need to know its properties such as resolution, duration, and bitrate. This information will help us determine the appropriate settings for compression without losing quality.
To check the properties of your input video using FFmpeg, open your terminal or command prompt and type the following command:
ffmpeg -i input_video.mp4
This command will display all the properties of your input video.
Step 3: Choose Video Codec
FFmpeg supports various codecs for video compression such as H.264, H.265 (HEVC), VP9, and AV1. These codecs offer different levels of compression efficiency and quality retention.
For example, H.264 offers high compression efficiency with minimal loss in quality compared to other codecs like MPEG-2 or MPEG-4.
To compress your video using H.264 codec, use the following command:
ffmpeg -i input_video.mp4 -c:v libx264 -preset slow -crf 22 output_video.mp4
In the above command, we have used the libx264 codec with a preset value of slow and a CRF (Constant Rate Factor) value of 22. The preset value determines the compression level, where slow provides better compression efficiency but at the cost of longer processing time. The CRF value ranges from 0-51, where lower values result in higher quality and larger file sizes.
Step 4: Choose Audio Codec
Similar to video codecs, FFmpeg supports various codecs for audio compression such as AAC, MP3, and Opus.
For example, AAC offers high compression efficiency with minimal loss in quality compared to other codecs like MP3.
To compress your audio using AAC codec, use the following command:
ffmpeg -i input_video.mp4 -c:v libx264 -preset slow -crf 22 -c:a aac -b:a 128k output_video.mp4
In the above command, we have added the -c:a aac option to choose AAC as our audio codec with a bitrate value of 128k.
Step 5: Choose Output Format
FFmpeg supports various output formats such as MP4, AVI, and MKV. It is recommended to use MP4 as it is widely supported across different platforms.
To compress your video into an MP4 format using FFmpeg, use the following command:
In this command, we have used output_video.mp4 as our output file name with all the settings that we have chosen so far.
Conclusion
Video compression using FFmpeg is an efficient and straightforward process that helps reduce the file size without compromising on quality. By choosing appropriate codecs, bitrates, and output formats, we can achieve high-quality compressed videos that are compatible with different platforms. Remember to experiment with different settings to find the optimal balance between compression efficiency and quality retention.
