How to Use the FFmpeg Showwaves Filter

This guide provides a straightforward tutorial on using the FFmpeg showwaves filter to convert audio inputs into visual waveform videos. You will learn the fundamental command syntax, explore key customization options like size, color, and drawing modes, and see practical examples of how to generate high-quality audio visualizers.

The showwaves filter in FFmpeg takes an audio input stream and converts it into a video stream that visually represents the audio’s amplitude over time. This is particularly useful for creating music videos for social media, podcasts, or analyzing audio signals.

Basic Command Syntax

To generate a simple waveform video from an audio file, use the following basic command structure:

ffmpeg -i input.mp3 -filter_complex "[0:a]showwaves=s=1280x720:mode=line[v]" -map "[v]" -map 0:a -c:v libx264 -c:a aac -b:a 192k output.mp4

How this command works:

-i input.mp3: Specifies your input audio file.
-filter_complex "[0:a]showwaves...[v]": Takes the first input’s audio stream ([0:a]), applies the showwaves filter with a resolution of 1280x720 using the line drawing mode, and outputs the video stream as [v].
-map "[v]" and -map 0:a: Maps both the newly generated waveform video and the original input audio to the output file.
-c:v libx264 -c:a aac: Encodes the video using H.264 and the audio using AAC for broad compatibility.

Key Customization Parameters

You can customize the appearance of the waveform by passing arguments to the showwaves filter using the syntax showwaves=parameter1=value1:parameter2=value2.

Parameter	Description	Common Values
`size` or `s`	Sets the resolution of the output video.	`1920x1080`, `1280x720`, `640x480`
`mode`	Defines how the waveform is drawn.	`point`, `line`, `p2p` (point-to-point), `cline` (centered line)
`colors`	Specifies the color of the waveform. Can be defined by name or hex code.	`red`, `blue`, `0x00FF00`, `white\\|yellow` (for multi-channel)
`scale`	Sets the amplitude scale.	`lin` (linear), `log` (logarithmic), `sqrt` (square root)
`rate` or `r`	Sets the video frame rate.	`25`, `30`, `60`

Practical Examples

1. Multi-Channel Colored Waveform

If you have a stereo audio file, you can assign different colors to the left and right channels by separating the colors with a pipe (|) character:

ffmpeg -i input.wav -filter_complex "[0:a]showwaves=s=1920x1080:mode=line:colors=red|blue[v]" -map "[v]" -map 0:a -c:v libx264 -pix_fmt yuv420p output.mp4

2. High Frame-Rate Solid Waveform (p2p mode)

For a denser, more solid-looking waveform, use the p2p (point-to-point) mode and increase the frame rate to 60 frames per second:

ffmpeg -i input.mp3 -filter_complex "[0:a]showwaves=s=1280x720:mode=p2p:rate=60:colors=0x33FF33[v]" -map "[v]" -map 0:a -c:v libx264 output.mp4

3. Overlaying Waveform on a Background Image

To make a professional video, you can overlay the transparent waveform on top of a static background image:

ffmpeg -loop 1 -i background.jpg -i input.mp3 -filter_complex "[1:a]showwaves=s=1920x1080:mode=line:colors=white:format=rgba[wave];[0:v][wave]overlay=format=auto:shortest=1[outv]" -map "[outv]" -map 1:a -c:v libx264 -c:a aac output.mp4

Note: In the overlay command, format=rgba is passed to the showwaves filter to ensure the waveform background is transparent, allowing the image underneath to be visible.