Color Correction with FFmpeg — curves / eq / colorbalance Filters

Q: Should I use eq or curves for colour correction?

Use `eq` for global brightness/contrast/saturation tweaks and `curves` for shaping highlights/midtones/shadows independently. `curves` is closer to a real grading workflow.

Q: Can I apply a 3D LUT instead?

Yes — `lut3d` accepts `.cube` files: `ffmpeg -i in.mp4 -vf lut3d=look.cube out.mp4`. LUTs are the standard way to ship a graded look.

Q: Does this preserve HDR colour?

No — most simple `eq`/`curves` pipelines clip HDR highlights. For HDR sources convert to linear with `zscale`, grade, then convert back.

What You’ll Learn

How to adjust brightness, contrast, saturation, and gamma with the eq filter
Fine-grained tone correction with the curves filter
Using the colorbalance filter to tint shadows, midtones, and highlights
How to pick the right filter for the job
Combining multiple filters for a practical color-correction pipeline

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

eq — Basic Brightness, Contrast, and Saturation Controls

The simplest color-adjustment filter. Each parameter is explored in depth in adjusting brightness, contrast, and saturation with eq.

ffmpeg -i input.mp4 -vf "eq=brightness=0.1:contrast=1.2:saturation=1.3:gamma=1.0" output.mp4

Parameter	Range	Default	Description
`brightness`	-1.0 to 1.0	0	Brightness (0 = no change)
`contrast`	-1000 to 1000	1	Contrast (1 = no change)
`saturation`	0 to 3.0	1	Saturation (1 = no change, 0 = grayscale)
`gamma`	0.1 to 10	1	Gamma correction (1 = no change)

Common Adjustments

Brighten slightly and boost contrast:

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

Convert to grayscale:

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

curves — Fine-Grained Tone Curves

Control-point placement and per-channel shaping are covered in detail in tone curve color correction with curves. An S-curve for a contrast boost:

ffmpeg -i input.mp4 -vf "curves=all='0/0 0.25/0.15 0.5/0.5 0.75/0.85 1/1'" output.mp4

Specify control points as all='input/output ...' (normalized 0–1).

Per-Channel Adjustments

Lift the red channel for a warmer look:

ffmpeg -i input.mp4 -vf "curves=red='0/0 0.5/0.6 1/1'" output.mp4

Lower the blue channel to reduce cool tones:

ffmpeg -i input.mp4 -vf "curves=blue='0/0 0.5/0.4 1/0.9'" output.mp4

Using Presets

ffmpeg -i input.mp4 -vf "curves=preset=vintage" output.mp4

Available presets: none, color_negative, cross_process, darker, increase_contrast, lighter, linear_contrast, medium_contrast, negative, strong_contrast, vintage.

colorbalance — Tint Shadows / Midtones / Highlights

Shift the shadows cooler (more blue) and warm the highlights slightly:

ffmpeg -i input.mp4 -vf "colorbalance=bs=0.1:rs=-0.1:gh=0.1" output.mp4

Parameter	Description
`rs/gs/bs`	R/G/B adjustment for shadows (-1 to 1)
`rm/gm/bm`	R/G/B adjustment for midtones
`rh/gh/bh`	R/G/B adjustment for highlights

Combining Filters

Full pipeline with eq and colorbalance:

ffmpeg -i input.mp4 -vf "eq=brightness=0.05:contrast=1.1,colorbalance=rs=-0.05:bs=0.05" output.mp4

Which Filter to Use

Goal	Recommended filter
Quickly tune brightness, contrast, or saturation	`eq`
Shape tone with curves	`curves`
Independently color shadows, midtones, and highlights	`colorbalance`
Apply a .cube LUT	`lut3d`

Measured Example

This example applies a light color correction to a 1080p/30fps, 2-minute H.264 video:

ffmpeg -i input.mp4 \
  -vf "eq=brightness=0.04:contrast=1.12:saturation=1.15,colorbalance=bs=0.04:rh=0.03" \
  -c:v libx264 -crf 23 -preset medium -c:a copy \
  output.mp4

eq and colorbalance are relatively light filters, but any video filter requires video re-encoding. On a typical 8-core desktop, processing often lands around 1–2x real time.

File size is driven more by -crf, -preset, and source noise than by the filter names themselves. Lifting dark areas can reveal noise and slightly increase size at the same CRF. Results vary by environment.

Frequently Asked Questions

Should I use eq or curves for colour correction?

Use eq for global brightness/contrast/saturation tweaks and curves for shaping highlights/midtones/shadows independently. curves is closer to a real grading workflow.

What is the difference between gamma and brightness?

Brightness is a linear shift; gamma is a non-linear curve that brightens midtones without crushing highlights or blacks. Gamma usually looks more natural.

Why does the corrected video look greenish?

You probably touched the green curve or saturation aggressively. Reset that channel and apply changes uniformly first, then push individual channels last.

Can I apply a 3D LUT instead?

Yes — lut3d accepts .cube files: ffmpeg -i in.mp4 -vf lut3d=look.cube out.mp4. LUTs are the standard way to ship a graded look.

Does this preserve HDR colour?

No — most simple eq/curves pipelines clip HDR highlights. For HDR sources convert to linear with zscale, grade, then convert back.

3D LUT Color Grading — Apply .cube Files to Video
Sharpening and Blurring — Adjust Clarity with the unsharp Filter

Tested with ffmpeg 6.1 / Ubuntu 24.04 (検証スクリプトで実行確認) Primary sources: ffmpeg.org/ffmpeg-filters.html#curves / ffmpeg.org/ffmpeg-filters.html#eq / ffmpeg.org/ffmpeg-filters.html#colorbalance