--- title: "Set a shader video effect on a vision mixer block (input look or PGM master)." method: POST path: "/api/flows/{flow_id}/blocks/{block_id}/effect" tags: ["flows"] --- # Set a shader video effect on a vision mixer block (input look or PGM master). `POST /api/flows/{flow_id}/blocks/{block_id}/effect` Requires the shader FX engine (GPU backend with Shader FX enabled) — returns 400 when the engine is not built into the running pipeline. ## Path parameters - `flow_id` string, required - `block_id` string, required ## Request body - SetVideoEffectRequest — Request to set a video effect on a vision mixer block. - `effect` union, required — A persistent video effect ("look") applied to a vision mixer input or to the PGM master output. JSON encoding is internally tagged on `type`: `{"type": "pixelate", "block_size": 24.0}`. All numeric parameters are clamped server-side (see [`VideoEffect::sanitized`]); colors are `#RRGGBB` hex strings. - object — No effect (identity passthrough). - `type` 'none', required - object — Chroma key: pixels close to `key_color` become transparent. - `key_color` string — Key color as `#RRGGBB` (typically green `#00B140` or blue). - `similarity` number, float — Chroma distance below which pixels are fully keyed (0..1). - `smoothness` number, float — Soft edge width added above `similarity` (0..1). - `spill` number, float — Spill suppression amount — desaturates key-colored fringes (0..1). - `type` 'chroma_key', required - object — Mosaic pixelation (privacy or stylization). - `block_size` number, float — Block size in source pixels (2..200). - `type` 'pixelate', required - object — Disc-bokeh defocus blur (24-tap Vogel spiral, single pass). - `radius` number, float — Blur radius in source pixels (0..40). - `type` 'blur', required - object — Two-color luma mapping. `low`=black point color, `high`=white point color. Grayscale = `#000000`/`#FFFFFF`, sepia = `#2B1D0E`/`#FFF1DF`. - `high` string - `low` string - `mix` number, float — Blend between original (0) and duotone (1). - `type` 'duotone', required - object — Darkened corners. - `amount` number, float — Strength of the darkening (0..1). - `softness` number, float — Falloff softness (0.01..1). - `type` 'vignette', required - object — Animated VHS look: chroma shift, scanlines, tape noise. - `intensity` number, float — Overall intensity (0..1). - `type` 'vhs', required - object — Animated old-film look: grain, flicker, scratches, warm tone. - `intensity` number, float — Overall intensity (0..1). - `type` 'old_film', required - object — Edge detection glow added on top of the image. - `color` string — Glow color as `#RRGGBB`. - `intensity` number, float — Glow strength (0..1). - `type` 'edge_glow', required - object — CRT monitor: barrel distortion, scanlines, RGB grille. - `intensity` number, float — Overall intensity (0..1). - `type` 'crt', required - object — Newspaper-print halftone dots. - `dot_size` number, float — Dot grid size in pixels (3..40). - `type` 'halftone', required - object — Thermal-camera false color over luma. - `intensity` number, float — Blend between original (0) and thermal (1). - `type` 'thermal', required - object — Night-vision scope: green phosphor, lifted shadows, grain, vignette. - `intensity` number, float — Blend between original (0) and night vision (1). - `type` 'night_vision', required - object — Color quantization into bands (screen-print / toon). - `levels` number, float — Number of levels per channel (2..16). - `type` 'posterize', required - object — Underwater: wavy refraction, blue-green grade, caustic shimmer. - `intensity` number, float — Overall intensity (0..1). - `type` 'underwater', required - object — Primary color correction + white balance — the camera-matching tool. Every control is neutral at its default, so an untouched correction is an identity pass. Applied in a fixed order: white balance, brightness, contrast, hue, saturation, gamma. - `brightness` number, float — Additive brightness offset (-1..1, neutral 0). - `contrast` number, float — Contrast multiplier around mid-gray (0..2, neutral 1). - `gamma` number, float — Midtone gamma curve (0.1..3, neutral 1). - `hue` number, float — Hue rotation: -1..1 maps to -180..180 degrees (neutral 0). - `saturation` number, float — Saturation: 0 = grayscale, 1 = unchanged, up to 2 (0..2, neutral 1). - `temperature` number, float — White balance temperature: warm (+) / cool (-) (-1..1, neutral 0). - `tint` number, float — White balance tint: magenta (+) / green (-) (-1..1, neutral 0). - `type` 'color_correct', required - `target` union, required — Where a [`VideoEffect`] is applied on a vision mixer block. - object — A video input by index — the effect follows the source everywhere (PGM, PVW, thumbnails, PiPs). - `input` integer, required — A video input by index — the effect follows the source everywhere (PGM, PVW, thumbnails, PiPs). - 'master' — The PGM master output — applied after composition. ## Response `200` Effect applied - SetVideoEffectResponse — Response after setting a video effect. - `effect` union, required — A persistent video effect ("look") applied to a vision mixer input or to the PGM master output. JSON encoding is internally tagged on `type`: `{"type": "pixelate", "block_size": 24.0}`. All numeric parameters are clamped server-side (see [`VideoEffect::sanitized`]); colors are `#RRGGBB` hex strings. - object — No effect (identity passthrough). - `type` 'none', required - object — Chroma key: pixels close to `key_color` become transparent. - `key_color` string — Key color as `#RRGGBB` (typically green `#00B140` or blue). - `similarity` number, float — Chroma distance below which pixels are fully keyed (0..1). - `smoothness` number, float — Soft edge width added above `similarity` (0..1). - `spill` number, float — Spill suppression amount — desaturates key-colored fringes (0..1). - `type` 'chroma_key', required - object — Mosaic pixelation (privacy or stylization). - `block_size` number, float — Block size in source pixels (2..200). - `type` 'pixelate', required - object — Disc-bokeh defocus blur (24-tap Vogel spiral, single pass). - `radius` number, float — Blur radius in source pixels (0..40). - `type` 'blur', required - object — Two-color luma mapping. `low`=black point color, `high`=white point color. Grayscale = `#000000`/`#FFFFFF`, sepia = `#2B1D0E`/`#FFF1DF`. - `high` string - `low` string - `mix` number, float — Blend between original (0) and duotone (1). - `type` 'duotone', required - object — Darkened corners. - `amount` number, float — Strength of the darkening (0..1). - `softness` number, float — Falloff softness (0.01..1). - `type` 'vignette', required - object — Animated VHS look: chroma shift, scanlines, tape noise. - `intensity` number, float — Overall intensity (0..1). - `type` 'vhs', required - object — Animated old-film look: grain, flicker, scratches, warm tone. - `intensity` number, float — Overall intensity (0..1). - `type` 'old_film', required - object — Edge detection glow added on top of the image. - `color` string — Glow color as `#RRGGBB`. - `intensity` number, float — Glow strength (0..1). - `type` 'edge_glow', required - object — CRT monitor: barrel distortion, scanlines, RGB grille. - `intensity` number, float — Overall intensity (0..1). - `type` 'crt', required - object — Newspaper-print halftone dots. - `dot_size` number, float — Dot grid size in pixels (3..40). - `type` 'halftone', required - object — Thermal-camera false color over luma. - `intensity` number, float — Blend between original (0) and thermal (1). - `type` 'thermal', required - object — Night-vision scope: green phosphor, lifted shadows, grain, vignette. - `intensity` number, float — Blend between original (0) and night vision (1). - `type` 'night_vision', required - object — Color quantization into bands (screen-print / toon). - `levels` number, float — Number of levels per channel (2..16). - `type` 'posterize', required - object — Underwater: wavy refraction, blue-green grade, caustic shimmer. - `intensity` number, float — Overall intensity (0..1). - `type` 'underwater', required - object — Primary color correction + white balance — the camera-matching tool. Every control is neutral at its default, so an untouched correction is an identity pass. Applied in a fixed order: white balance, brightness, contrast, hue, saturation, gamma. - `brightness` number, float — Additive brightness offset (-1..1, neutral 0). - `contrast` number, float — Contrast multiplier around mid-gray (0..2, neutral 1). - `gamma` number, float — Midtone gamma curve (0.1..3, neutral 1). - `hue` number, float — Hue rotation: -1..1 maps to -180..180 degrees (neutral 0). - `saturation` number, float — Saturation: 0 = grayscale, 1 = unchanged, up to 2 (0..2, neutral 1). - `temperature` number, float — White balance temperature: warm (+) / cool (-) (-1..1, neutral 0). - `tint` number, float — White balance tint: magenta (+) / green (-) (-1..1, neutral 0). - `type` 'color_correct', required - `message` string, required ## Other responses - `400` — Invalid request or FX engine unavailable ## Changes > 25 revisions in range; 18 could not be searched. - **2026-04-07** `1e67862a080e` — 1 breaking - api path removed without deprecation [Change history](https://skmtc.dev/eyevinn/apis/strom-api/changes/api/flows/:flow_id/blocks/:block_id/effect/post.md) --- [API](https://skmtc.dev/eyevinn/apis/strom-api.md) · [All operations](https://skmtc.dev/eyevinn/apis/strom-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/eyevinn/strom-api/revisions/0df7ca64263f/schema)