# StableKey – CorridorKey Neural Green-Screen Keyer

> StableKey – CorridorKey Neural Green-Screen Keyer is a paid API for AI agents from stablekey.dev, paid per call via x402, $5/call, status unknown (last checked 2026-09-15).

Processes a green-screen video plate using Corridor Digital's CorridorKey neural keyer to produce VFX-grade alpha matte, straight foreground, and premultiplied RGBA output videos

## Facts

- Endpoint: POST https://stablekey.dev/api/process
- Price: $5/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/stablekey-corridorkey-neural-green-screen-keyer-1c1ceaee
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_vQg1iERln2hTVkIb3VKPV

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability stablekey-corridorkey-neural-green-screen-keyer-1c1ceaee -d '<json body>'
```

Example prompt: Can you run CorridorKey neural keying on this green-screen plate and give me back the alpha matte, straight foreground, and premultiplied RGBA videos so I can composite it in my VFX pipeline?

## When to prefer this

Choose this endpoint when you need VFX-grade green-screen removal with neural accuracy rather than simple color-range chroma keying. Particularly suited for professional post-production pipelines that require separate alpha, straight foreground, and premultiplied RGBA outputs. Ideal when standard chroma key tools produce fringe artifacts or struggle with fine hair/edge detail.

## Known failure modes

- Invalid or inaccessible video file URL returns error
- Non-green-screen footage may yield poor keying results
- Payment failure (insufficient USDC balance) blocks processing
- Unsupported video format or codec may cause rejection
- Server timeout on very large or long video files

## How this service works

VFX-grade green-screen unmixing via Corridor Digital&#x27;s CorridorKey neural keyer. Submit a green-screen plate, get back alpha + straight foreground + premultiplied RGBA mp4s. Operated at cost via x402.

## Output

Returns JSON containing URLs or data for three output MP4 files: an alpha matte channel video, a straight (unmultiplied) foreground video, and a premultiplied RGBA composite-ready video — all produced by the CorridorKey neural keyer at VFX grade quality.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "type": {
   "type": "string",
   "const": "stablekey-video"
  },
  "rgbUrl": {
   "type": "string",
   "format": "uri",
   "description": "StableUpload public URL of the source RGB plate (mp4)."
  },
  "hintUrl": {
   "type": "string",
   "format": "uri",
   "description": "OPTIONAL StableUpload public URL of a coarse alpha hint mp4. When omitted, stablekey generates a chroma-key hint inline (works on clean studio plates). Bring your own SAM-derived mask via stablesam.dev for gnarly shots: subject wearing green, busy non-green BG props, multiple subjects, translucent FG."
  },
  "options": {
   "type": "object",
   "required": [
    "despillStrength",
    "autoDespeckle",
    "despeckleSize",
    "refinerScale"
   ],
   "properties": {
    "refinerScale": {
     "type": "number",
     "default": 1,
     "maximum": 2,
     "minimum": 0
    },
    "autoDespeckle": {
     "type": "boolean",
     "default": true
    },
    "despeckleSize": {
     "type": "integer",
     "default": 400,
     "maximum": 9007199254740991,
     "minimum": 0
    },
    "despillStrength": {
     "type": "number",
     "default": 1,
     "maximum": 1,
     "minimum": 0
    }
   },
   "additionalProperties": false
  },
  "outputs": {
   "type": "object",
   "required": [
    "alpha",
    "fg",
    "processed"
   ],
   "properties": {
    "fg": {
     "type": "object",
     "required": [
      "publicUrl"
     ],
     "properties": {
      "postUrl": {
       "type": "string",
       "format": "uri"
      },
      "publicUrl": {
       "type": "string",
       "format": "uri",
       "description": "Resulting public URL where the output will land after Modal uploads it."
      },
      "uploadUrl": {
       "type": "string",
       "format": "uri"
      },
      "postFields": {
       "type": "object",
       "propertyNames": {
        "type": "string"
       },
       "additionalProperties": {
        "type": "string"
       }
      }
     },
     "description": "Storage slot for the recovered straight foreground mp4 (sRGB).",
     "additionalProperties": false
    },
    "alpha": {
     "type": "object",
     "required": [
      "publicUrl"
     ],
     "properties": {
      "postUrl": {
       "type": "string",
       "format": "uri"
      },
      "publicUrl": {
       "type": "string",
       "format": "uri",
       "description": "Resulting public URL where the output will land after Modal uploads it."
      },
      "uploadUrl": {
       
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/stablekey-corridorkey-neural-green-screen-keyer-1c1ceaee/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from stablekey.dev](https://www.zero.xyz/host/stablekey.dev/llms.txt)