heyburns-PortraitUtils/docs/AutoAdjustSuite.md

Auto Adjust Suite

AutoAdjustV2 (displayed as Auto Adjust (Photoshop-style)) provides conservative, Photoshop-style automatic contrast, tone, and color correction. Adobe's exact selection heuristics are proprietary, so the results are designed to follow the documented behavior rather than be a bit-for-bit Photoshop clone.

Choosing an adjustment

The three corrections are normally alternatives. Use adjustment_mode to pick one command directly:

• Auto Levels applies one black/white-point stretch to all RGB channels. It preserves channel relationships and corresponds most closely to Photoshop's Auto Contrast / Enhance Monochromatic Contrast behavior.
• Auto Tone in Per-channel mode calculates black and white points for R, G, and B independently. This corresponds to Photoshop Auto Tone / automatic Levels and can remove or introduce a color cast.
• Auto Color identifies average dark and light colors, sets channel endpoints, and can neutralize a genuinely low-chroma midtone. It refuses to treat saturated skin, foliage, or colored lighting as a gray reference.

Use Finish Config switches lets the three booleans in Finish & Run Config control execution. Enabling several switches intentionally stacks them in this order:

Auto Levels -> Auto Tone -> Auto Color

That is more aggressive than the normal Photoshop workflow and can increase clipping, so use it only when the stacked result is intentional.

Inputs

• image – ComfyUI image batch. RGB, grayscale, and RGBA are accepted; alpha is preserved and fully transparent pixels are excluded from statistics.
• finish_config – Required PORTRAIT_FINISH_CONFIG_V2 bundle carrying auto_levels, auto_tone, auto_color, and flip_horizontal.
• precision – Histogram (fast) uses 256 bins and is recommended for normal photographic work, especially after upscaling. Exact sorts all pixels for exact percentile measurements.
• levels_shadow_clip_pct / levels_highlight_clip_pct – Extreme pixels ignored when setting the shared Levels endpoints. These settings are also used by Auto Color. Photoshop's traditional default is 0.1%.
• levels_gamma_normalize – Optional custom midtone normalization. This is a Levels-style convenience, not part of Photoshop Auto Contrast.
• tone_mode – Per-channel matches Auto Tone. Monochromatic uses the same color-preserving method as Auto Levels.
• tone_shadow_clip_pct / tone_highlight_clip_pct – Clipping percentages for Auto Tone.
• snap_neutral_midtones – Used by Auto Color. Candidate pixels must be in the midtone range and have low chroma before they can influence color balance.
• flip_horizontal (in Finish & Run Config) – Mirrors RGB and alpha after adjustment.
• adjustment_mode – Select one Photoshop-style command exclusively, or use the switches supplied by Finish & Run Config.
• strength – Blends the corrected image with the original from 0 to 100%, comparable to lowering an adjustment layer's opacity.

Flat or nearly flat channels are left unchanged rather than being expanded into noise or mapped to black. A clip value of zero is supported and uses the true minimum or maximum.

Suggested starting points

• Color already looks correct, but contrast is weak: select Auto Levels.
• Each RGB channel occupies a noticeably different range: select Auto Tone in Per-channel mode.
• The image has a plausible neutral object but a global color cast: select Auto Color with snap_neutral_midtones on.
• Portrait dominated by intentional warm light: prefer Auto Levels; inspect Auto Color carefully before using it.

Shared configuration

PortraitFinishConfigV2 shares the four workflow switches auto_levels, auto_tone, auto_color, and flip_horizontal in one typed bundle. Connect it directly to each adjustment node's finish_config socket. The old standalone Auto Adjust and AutoColor Config interfaces have been removed.