web: add the B&W HIGH CONTRAST film sim to the PRESETS rail

The chip lands after ACRIPES and is a mono stock of its own, so it gets its own
baseFilter ('mono-high-contrast') rather than borrowing Acros': the PHOTO STYLE
chips are keyed by baseFilter, and the two greys must sit side by side.

The look is the B&W MIX plus a push at both ends. The mix rides the matrix — a
non-BT.709 row set (0.38/0.56/0.06, identical rows, sum 1.00) so a red roof
reads bright, a blue sky deep, and the separation is contrast before any curve.
The push rides FILM_TONE (shadow -0.32, highlight +0.26) so the ends move
without touching the midtones, and the midtone slope is SIM_CONTRAST_BIAS (4
contrast units) next to the sim's own exposure bias. The knobs stay at neutral:
a sim is colour and tone only.

Both B&W stocks being mono is now asked once, through isMonochromeBase, so the
colour-only stages (saturation, white balance, R/B fine-tune, chrome, hue
mixer) and the MONO strip label can never half-apply to one of them.

docker/frontend/shared/types/index.ts

@@ -68,7 +68,11 @@ export const MIN_CROP_FRAC = 0.08;
 // cool tint in shade, plus a seasonal atmospheric haze/fog veil.
 export type CinemaSeason = 'spring' | 'summer' | 'autumn' | 'winter';
 
-export type BaseFilter = 'classic-neg' | 'classic-chrome' | 'classic-vivid' | 'provia' | 'velvia' | 'astia' | 'eterna' | 'monochrome' | 'leica' | 'leica-vivid' | 'none';
+// `monochrome` is Acros' grey ramp; `mono-high-contrast` is the B&W HIGH
+// CONTRAST stock's own — both are black-and-white, so anything that asks "is
+// this a colour stock?" must ask it through isMonochromeBase (colorUtils.ts)
+// rather than comparing against one of these two strings.
+export type BaseFilter = 'classic-neg' | 'classic-chrome' | 'classic-vivid' | 'provia' | 'velvia' | 'astia' | 'eterna' | 'monochrome' | 'mono-high-contrast' | 'leica' | 'leica-vivid' | 'none';
 
 // The eight hue bands of the selective-colour mixer, in the order they wrap
 // around the wheel. HSL_BANDS (shared/utils/colorUtils.ts) carries the anchor

docker/frontend/shared/utils/colorUtils.ts

@@ -147,6 +147,22 @@ const SIM_EXPOSURE_BIAS: Partial<Record<BaseFilter, number>> = {
   'leica-vivid': 2,
 };
 
+// A second brightness a stock owns, in Contrast-slider units. The knob itself
+// stays at 0 (a sim is colour only), so the extra slope is added here, where
+// the knob's own gain/offset mapping already lives.
+const SIM_CONTRAST_BIAS: Partial<Record<BaseFilter, number>> = {
+  'mono-high-contrast': 4,
+};
+
+// Black-and-white stocks. Their grey ramp is the whole look, so every
+// colour-only stage below — saturation, white balance, the R/B fine-tune — is
+// skipped for them, and the tone pass leaves the hue mixer alone. One list,
+// asked through one function, so a second B&W stock cannot end up half
+// excluded (a stray Kelvin gain on a grey ramp shows up as a tint).
+const MONO_BASES: BaseFilter[] = ['monochrome', 'mono-high-contrast'];
+export const isMonochromeBase = (baseFilter: BaseFilter | undefined): boolean =>
+  !!baseFilter && MONO_BASES.includes(baseFilter);
+
 // Generate a 4x5 ColorMatrix (array of 20 floats) based on base style and
 // adjustments. Tone-domain knobs (dynamicRange/highlight/shadow) and the
 // exposure-compensation EV gain are intentionally NOT part of the matrix —
@@ -160,7 +176,7 @@ export function getSkiaColorMatrix(baseFilter: BaseFilter, adj: ColorAdjustments
   // mapping the knob uses, so the pixels get the lift the stock needs while the
   // UI keeps reading 0.
   const exposure = (adj.exposure ?? 0) + (SIM_EXPOSURE_BIAS[baseFilter] ?? 0);
-  const contrast = adj.contrast;
+  const contrast = adj.contrast + (SIM_CONTRAST_BIAS[baseFilter] ?? 0);
   const saturation = adj.saturation;
   const temperature = adj.temperature;
   const tint = adj.tint;
@@ -302,10 +318,40 @@ export function getSkiaColorMatrix(baseFilter: BaseFilter, adj: ColorAdjustments
       r, g, b, 0, 0,
       0, 0, 0, 1, 0,
     ];
+  } else if (baseFilter === 'mono-high-contrast') {
+    // B&W HIGH CONTRAST — Acros taken through a warm filter, then pushed at the
+    // ends (the push itself lives in FILM_TONE, and its midtone slope in
+    // SIM_CONTRAST_BIAS above).
+    //
+    // The mix is the B&W MIX step: the channel weights are the matrix's whole
+    // job here, and they are deliberately not BT.709. Red is nearly doubled
+    // against its luminance share, orange and yellow hold or gain slightly
+    // (their rows carry the red weight plus a green one), while blue and green
+    // fall — so a red roof reads bright, a blue sky and foliage read deep, and
+    // the separation between them is what gives the ramp its contrast before
+    // any curve is applied.
+    //
+    // ponytail: the weights ride the CHANNELS, while the brief that asked for
+    // this stock names HUE groups (red 1.15, orange 1.20, blue 0.70). A 4x5
+    // matrix cannot be hue-selective; if those exact factors are ever wanted,
+    // that is a per-pixel HSL pass in the tone shader (the mixer block already
+    // has the tent weights to do it), not a row edit here.
+    //
+    // The three rows are identical and sum to 1.00, so a neutral stays the
+    // neutral the sensor recorded and nothing clips at either end.
+    const r = 0.38;
+    const g = 0.56;
+    const b = 0.06;
+    matrix = [
+      r, g, b, 0, 0,
+      r, g, b, 0, 0,
+      r, g, b, 0, 0,
+      0, 0, 0, 1, 0,
+    ];
   }
 
   // 3. Apply Saturation adjustment (standard color matrix transformation)
-  if (baseFilter !== 'monochrome' && saturation !== 0) {
+  if (!isMonochromeBase(baseFilter) && saturation !== 0) {
     const s = 1 + (saturation / 10) * 0.5; // -10 maps to 0.5x, +10 maps to 1.5x saturation
     const invS = 1 - s;
     const r = 0.213 * invS;
@@ -329,7 +375,7 @@ export function getSkiaColorMatrix(baseFilter: BaseFilter, adj: ColorAdjustments
   // consumed by getToneUniforms instead.
 
   // 5. White Balance (Kelvin Temperature and Tint) — skip for monochrome to prevent color leakage
-  if (baseFilter !== 'monochrome') {
+  if (!isMonochromeBase(baseFilter)) {
     const rgbTemp = kelvinToRGB(temperature);
     // Tint is the green↔magenta axis, and it is symmetric: + pushes magenta
     // (red and blue up, green down), - pushes green (green up, red and blue
@@ -358,7 +404,7 @@ export function getSkiaColorMatrix(baseFilter: BaseFilter, adj: ColorAdjustments
   // perceptible size of one Fuji fine-tune step (-9..+9).
   const wbRed = adj.wbRed ?? 0;
   const wbBlue = adj.wbBlue ?? 0;
-  if (baseFilter !== 'monochrome' && (wbRed !== 0 || wbBlue !== 0)) {
+  if (!isMonochromeBase(baseFilter) && (wbRed !== 0 || wbBlue !== 0)) {
     const shiftMat = [
       1 + (wbRed / 9) * 0.1, 0, 0, 0, 0,
       0, 1, 0, 0, 0,

docker/frontend/shared/utils/defaultRecipes.ts

@@ -52,6 +52,7 @@ export const DEFAULT_ADJUSTMENTS: ColorAdjustments = {
 //   ASTIPES                Astia / Soft
 //   ETERNIPES              Eterna (cinema)
 //   ACRIPES                Acros (monochrome)
+//   B&W HIGH CONTRAST      Acros through a filter, ends pushed hard
 //   LC STREETLIFE CLASSIC  Leica Authentic Classic
 //   LC STREETLIFE VIVID    Leica Vivid
 export interface FilmSim {
@@ -70,6 +71,7 @@ export const FILM_SIMS: FilmSim[] = [
   { id: 'sim-astia', name: 'ASTIPES', baseFilter: 'astia', adjustments: { ...DEFAULT_ADJUSTMENTS } },
   { id: 'sim-eterna', name: 'ETERNIPES', baseFilter: 'eterna', adjustments: { ...DEFAULT_ADJUSTMENTS } },
   { id: 'sim-acros', name: 'ACRIPES', baseFilter: 'monochrome', adjustments: { ...DEFAULT_ADJUSTMENTS } },
+  { id: 'sim-bw-high-contrast', name: 'B&W HIGH CONTRAST', baseFilter: 'mono-high-contrast', adjustments: { ...DEFAULT_ADJUSTMENTS } },
   // The rangefinder digital look (M/Q/SL) is not a film stock, so it ships as its own
   // pair instead of one look that has to compromise. Both are still colour and
   // tone only: CLASSIC is Leica Authentic (the matrix carries the channel

docker/frontend/shared/utils/toneShader.ts

@@ -1,5 +1,5 @@
 import { BaseFilter, ColorAdjustments } from '../types';
-import { HSL_BANDS, hslBandGaps } from './colorUtils';
+import { HSL_BANDS, hslBandGaps, isMonochromeBase } from './colorUtils';
 
 // Tone-domain adjustments (Fuji-style Dynamic Range + Highlight/Shadow).
 // SkSL runtime effect over a child image shader.
@@ -331,6 +331,14 @@ const FILM_TONE: Partial<Record<BaseFilter, Partial<ToneUniforms>>> = {
   // Gains are TONE_SKSL's own (sh * 0.34, hl * 0.22), so -0.12 puts the toe at
   // ~5% and -0.05 trims the top ~1%.
   monochrome: { sh: -0.12, hl: -0.05 },
+  // B&W HIGH CONTRAST. Acros' ramp with both ends pushed hard: a deeper toe
+  // (-0.32 against Acros' -0.12) so the darks reach true black, and a shoulder
+  // that LIFTS instead of rolling (-0.05 → +0.26), which is the whites step of
+  // the brief. Midtones see neither mask, so the long smooth stretch between
+  // the two ends survives — that is what keeps a hard push off the posterised
+  // look, and the strength the stock needs on the greys is its matrix slope
+  // (SIM_CONTRAST_BIAS in colorUtils), not another mask here.
+  'mono-high-contrast': { sh: -0.32, hl: 0.26 },
 };
 
 export function getToneUniforms(adj: ColorAdjustments, baseFilter?: BaseFilter): ToneUniforms {
@@ -347,7 +355,7 @@ export function getToneUniforms(adj: ColorAdjustments, baseFilter?: BaseFilter):
   // Color Chrome depth per stop of the UI's none/weak/strong. A chrome set is a
   // monochrome look, so both are forced off there: the effect is colour-only
   // (the preview/export matrix skips them for monochrome for the same reason).
-  const colour = baseFilter !== 'monochrome';
+  const colour = !isMonochromeBase(baseFilter);
   const chromeDepth = (v: ColorAdjustments['colorChrome'] | undefined) =>
     !colour || v === 'none' || v == null ? 0 : v === 'strong' ? 0.9 : 0.45;
   const blueDepth = (v: ColorAdjustments['colorChromeBlue'] | undefined) =>

docker/frontend/src/App.tsx

@@ -33,7 +33,7 @@ import {
   type HslBandId,
   type Recipe,
 } from '../shared/types';
-import { HSL_BANDS, nearestHslBand, rgbToHsl } from '../shared/utils/colorUtils';
+import { HSL_BANDS, isMonochromeBase, nearestHslBand, rgbToHsl } from '../shared/utils/colorUtils';
 import type { MsgKey } from './i18n/vi';
 
 // Mirrors the API's MAX_PHOTOS_PER_USER: shown on SAVE PHOTO, enforced there.
@@ -1140,7 +1140,7 @@ export function Workspace() {
     const slug = name.replace(/[^\p{L}\p{N}]+/gu, '_').replace(/^_+|_+$/g, '').toUpperCase();
     const grain = Math.max(0, Math.round(recipe.adjustments.grain ?? 0));
     const warmth = Math.round((recipe.adjustments.temperature - 5500) / 250);
-    const tail = recipe.baseFilter === 'monochrome' ? 'MONO' : `WARMTH ${warmth >= 0 ? '+' : ''}${warmth}`;
+    const tail = isMonochromeBase(recipe.baseFilter) ? 'MONO' : `WARMTH ${warmth >= 0 ? '+' : ''}${warmth}`;
     return { tag: `#${slug || 'RECIPE'}`, title: name, meta: `ISO ${iso ?? 'AUTO'} · GRAIN ${grain} · ${tail}` };
   }, [recipe.name, recipe.adjustments, recipe.baseFilter, iso]);
 
@@ -1960,7 +1960,7 @@ export function Workspace() {
   // FX's MONOCHROME switch is not a look of its own: it swaps the base filter
   // for the mono stock and swaps right back. Adjustments are never touched, so
   // a knob moved while the switch is on survives the trip back.
-  const monoOn = recipe.baseFilter === 'monochrome';
+  const monoOn = isMonochromeBase(recipe.baseFilter);
   const toggleMono = () => {
     remember();
     if (monoOn) {