# Relaystation Audio Waveform & Spectrogram Renderer

> Relaystation Audio Waveform & Spectrogram Renderer is a paid API for AI agents from api.relaystation.ai, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-13).

Renders an audio file as a waveform or spectrogram PNG image for visual track analysis

## Facts

- Endpoint: POST https://api.relaystation.ai/v1/media/waveform
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/relaystation-audio-waveform-spectrogram-renderer-01bd5096
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_YciEwHZTLcqLC6oXR3ng-

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 relaystation-audio-waveform-spectrogram-renderer-01bd5096 -d '<json body>'
```

Example prompt: Can you render a waveform PNG visualization of this podcast audio file at https://example.com/episode42.mp3?

## When to prefer this

Choose this endpoint when you need a fast, low-cost server-side audio visualization rendered as a PNG — ideal for pipelines that need waveform or spectrogram images without client-side rendering dependencies. Prefer it over client-side libraries when operating in headless or server environments, or when a consistent visual output format is required at scale.

## Known failure modes

- Unsupported audio format returns an error
- Invalid or unreachable audio URL causes fetch failure
- Audio file too large or too long may time out
- Missing required parameters returns a 400 bad request
- Insufficient x402 payment balance blocks the call

## How this service works

$0.0005/call. Render audio as a waveform or spectrogram PNG — visualize any track. 1¢ x402 min; remainder auto-credits — relaystation.ai/penny

## Output

A PNG image file containing either a waveform (amplitude over time) or spectrogram (frequency over time) visualization of the submitted audio. The image can be used directly in UIs, thumbnails, or analysis workflows.

## Request schema (JSON Schema)

```json
{
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "type": "object",
 "properties": {
  "input": {
   "type": "object",
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "type": "string",
     "enum": [
      "POST",
      "PUT",
      "PATCH"
     ]
    },
    "bodyType": {
     "type": "string",
     "enum": [
      "json",
      "form-data",
      "text"
     ]
    },
    "body": {
     "type": "object",
     "properties": {
      "file": {
       "type": "object",
       "description": "cputools input-source: { inline: <base64 ≤ 4 MiB> } or { inputKey: <scratch key ≤ 50 MB> }. The input container must sniff (ffprobe) to the live allowlist (operator-tunable cputools.media.input_formats): 3g2, 3gp, aac, asf, avi, flac, flv, gif, m4a, m4v, matroska, mj2, mov, mov,mp4,m4a,3gp,3g2,mj2, mp3, mp4, mpeg, mpegts, mpegvideo, ogg, wav, webm, wmv. An off-list input is a free 422 UNSUPPORTED_FORMAT."
      },
      "mode": {
       "type": "string",
       "enum": [
        "waveform",
        "spectrogram"
       ]
      },
      "width": {
       "type": "integer",
       "minimum": 100,
       "maximum": 2000
      },
      "height": {
       "type": "integer",
       "minimum": 50,
       "maximum": 1080
      },
      "color": {
       "type": "string",
       "enum": [
        "blue",
        "red",
        "green",
        "white",
        "black",
        "cyan",
        "magenta",
        "yellow",
        "orange",
        "gray"
       ]
      }
     }
    }
   },
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   },
   "required": [
    "type"
   ]
  }
 },
 "required": [
  "input"
 ]
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/relaystation-audio-waveform-spectrogram-renderer-01bd5096/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.relaystation.ai](https://www.zero.xyz/host/api.relaystation.ai/llms.txt)