Adjust Brightness, Contrast, Gamma, and Saturation with the eq Filter

What You Will Learn

• Commands for changing brightness, contrast, gamma, and saturation with the eq filter
• The meaning and value range of each parameter
• Practical corrections that combine multiple parameters
• How to specify parameters that change dynamically over time

Tested with: FFmpeg 6.1 (verified against real FFmpeg)
Target OS: Windows / macOS / Linux

Basic Commands

Increase Brightness

ffmpeg -i input.mp4 -vf "eq=brightness=0.1" output.mp4

The range of brightness is -1.0 to 1.0, with a default of 0. Positive values brighten the image, negative values darken it. For the bigger picture of when to reach for eq, curves, or colorbalance, see the color correction overview.

Increase Contrast

ffmpeg -i input.mp4 -vf "eq=contrast=1.5" output.mp4

The range of contrast is -1000.0 to 1000.0, with a default of 1. A value of 1 leaves the image unchanged; larger values increase contrast.

Apply Gamma Correction

ffmpeg -i input.mp4 -vf "eq=gamma=1.5" output.mp4

The range of gamma is 0.1 to 10.0, with a default of 1. A value of 1 leaves the image unchanged; values of 1.5 or higher lift the shadows.

Adjust Saturation

ffmpeg -i input.mp4 -vf "eq=saturation=1.5" output.mp4

The range of saturation is 0.0 to 3.0, with a default of 1. A value of 0 produces grayscale, while 1.5 makes colors more vivid. To rotate the hue itself rather than just scale saturation, use the hue filter for hue and saturation.

Parameter Reference

Specifying Multiple Parameters at Once

ffmpeg -i input.mp4 -vf "eq=brightness=0.05:contrast=1.2:saturation=1.3:gamma=1.1" output.mp4

You can specify multiple parameters at once by separating them with a colon (:).

Adjusting White Balance with Per-Channel Gamma Correction

ffmpeg -i input.mp4 -vf "eq=gamma_r=0.9:gamma_g=1.0:gamma_b=1.1" output.mp4

By lowering the red channel slightly and raising the blue channel, you can shift the image toward a cooler tone.

Grayscale Conversion

ffmpeg -i input.mp4 -vf "eq=saturation=0" output.mp4

Setting saturation=0 converts the image to grayscale.

Dynamic Parameters (Changing Over Time)

The eq filter supports FFmpeg expressions.

ffmpeg -i input.mp4 -vf "eq=brightness='0.1*sin(t)'" output.mp4

Here t is the current timestamp in seconds. The result is an effect in which the brightness varies in a sine-wave pattern.

Practical Correction Examples

Brighten a Dark Video

ffmpeg -i input.mp4 -vf "eq=brightness=0.1:contrast=1.1:gamma=1.3" output.mp4

Make a Faded Video More Vivid

ffmpeg -i input.mp4 -vf "eq=saturation=1.4:contrast=1.15" output.mp4

Give the Video a Hard, Cinematic Look

ffmpeg -i input.mp4 -vf "eq=contrast=1.2:saturation=0.85:gamma=0.95" output.mp4

What Not to Do

Bad example: saturatoin (misspelled)
ffmpeg -i input.mp4 -vf "eq=saturatoin=1.5" output.mp4

Misspelling a parameter name results in an Invalid option error.

Differences from the hue Filter

The eq filter is best for fine tonal adjustments, while hue is best for changing the hue.

Measured Example

This example adjusts brightness, contrast, saturation, and gamma on a 1080p/30fps, 2-minute H.264 video:

ffmpeg -i input.mp4 \
  -vf "eq=brightness=0.04:contrast=1.15:saturation=1.2:gamma=1.05" \
  -c:v libx264 -crf 23 -preset medium -c:a copy \
  output.mp4

eq is lightweight, but because it changes video frames, -c:v copy cannot be used. On a typical 8-core desktop, processing is often around 1–2x real time.

At the same CRF, file size depends on the correction. Lifting shadows can reveal noise and increase size; reducing saturation or darkening the image can reduce it. In practice, combine small changes to gamma, contrast, and brightness rather than pushing one parameter too far. Results vary by environment.

Common Pitfalls

• Symptom: an Invalid option error. Cause: a misspelled parameter name such as saturatoin. Fix: check the spelling of brightness, contrast, saturation, and gamma. Copying the names straight from the parameter table above is the safest way.

• Symptom: brightening blows out the highlights. Cause: brightness was raised too far and the highlights are pinned at 255. Fix: keep brightness small (0.03–0.05) and combine it with gamma=1.1 and contrast=1.05, which lifts the shadows without clipping the highlights.

• Symptom: the dynamic expression brightness='0.1*sin(t)' is treated as a constant. Cause: the quotes were stripped so the expression is never evaluated. Fix: keep the expression in '...' and the whole filter in "...", preserving the nested quotes.

• Symptom: re-encoding is slow / -c:v copy does not work. Cause: eq is a video filter that rewrites pixels, so a re-encode is mandatory. Fix: keep the audio with -c:a copy, and tune crf on a short segment before processing the whole file.

FAQ

Q. What is the difference between brightness and gamma? A. brightness is an offset that adds a constant across the whole image, moving shadows and highlights equally. gamma is non-linear and mainly lifts (>1) or sinks (<1) the mid-to-shadow tones. For a natural brightening, gamma is less prone to clipping.

Q. What is the easiest way to make it grayscale? A. eq=saturation=0. It drops the color information entirely.

Q. Can I adjust white balance? A. You can approximate it with per-channel gamma: gamma_r, gamma_g, gamma_b. Lowering red and raising blue shifts cooler; the reverse shifts warmer.

Q. Why is the contrast range so wide (-1000 to 1000)? A. That is just the allowed range. In practice 0.8–1.5 is plenty; extreme values break the image quickly. A value of 1 is the no-change baseline.

Q. Should I use eq or curves? A. For nudging overall brightness, saturation, and gamma together, eq is the quick choice. When you need to shape highlights and shadows separately, curves gives finer control.

Related Filters

• hue — Adjusts hue, saturation, and luminance
• curves — Tone-curve-based color correction
• colorbalance — Color adjustment for shadows, midtones, and highlights