FFmpeg is a powerful multimedia framework that can decode, encode, transcode, mux, demux, stream, filter, and play almost anything that humans and machines have created. It's particularly useful on a Raspberry Pi for tasks such as converting video formats, streaming video, and capturing video from a camera.

Installing FFmpeg on Raspberry Pi

Before you can start using FFmpeg, you need to install it on your Raspberry Pi. Follow these steps to get started:

1. Update your system: Open a terminal on your Raspberry Pi and update your package list with the following command:

   sudo apt update && sudo apt upgrade -y

2. Install FFmpeg: Install FFmpeg using the package manager:

   sudo apt install ffmpeg -y

Examples of Using FFmpeg on Raspberry Pi

Example 1: Convert a Video File

Suppose you have a video file in MKV format and you want to convert it to MP4. Use the following command:

ffmpeg -i input_video.mkv -codec copy output_video.mp4

This command specifies the input file input_video.mkv and the output file output_video.mp4 while copying the codec to avoid re-encoding.

Example 2: Stream Video from Raspberry Pi Camera

If you have a Raspberry Pi camera module, you can stream video over your local network using FFmpeg. First, ensure you have raspivid installed, which is the camera capture utility for Raspberry Pi.

Use the following command to stream video:

raspivid -o - -t 0 -n -w 640 -h 480 -fps 25 | ffmpeg -re -ar 44100 -ac 2 -f s16le -acodec pcm_s16le -i /dev/zero -f h264 -i - -vcodec copy -f flv rtmp://your_streaming_server/live/stream_key

This command captures video from the camera and streams it to an RTMP server. Replace your_streaming_server/live/stream_key with your actual streaming server URL and stream key.

Example 3: Extract Audio from a Video File

To extract audio from a video file and save it as an MP3, use the following command:

ffmpeg -i input_video.mp4 -q:a 0 -map a output_audio.mp3

This command takes input_video.mp4 and extracts the audio track to output_audio.mp3.

Optimizing FFmpeg for Raspberry Pi

The Raspberry Pi has limited resources compared to a full-fledged PC, so it's important to optimize FFmpeg usage:

• Use hardware acceleration: If you have a Raspberry Pi model that supports hardware acceleration, consider using the h264_omx codec for encoding H.264 video to leverage the onboard GPU.
• Adjust resolution and bitrate: Lowering the resolution and bitrate of your output can significantly reduce the processing load.