> ## Documentation Index > Fetch the complete documentation index at: https://docs.budgetpixel.com/llms.txt > Use this file to discover all available pages before exploring further. # Classify a song's music genre > Classify one song into BudgetPixel's canonical music genre taxonomy — the same classifier that powers the site's music gallery. **Synchronous**: the response carries the genre plus style/mood tags and a confidence score. **Input**: one song (`audio`), max **20 MB** and **7 minutes**, as MP3, WAV, OGG, M4A, or FLAC. Accepts a public URL, an uploaded-file URL from [`POST /v1/uploads`](/api-reference/files/upload-input-media), a data URI, or raw base64. Tip: a 7-minute WAV exceeds 20 MB — use MP3 for long tracks. The classifier listens to a ~30-second excerpt sampled from ~25% into the track (the `clip` field in the response tells you the exact window). Only that excerpt is retained — privately, for ~1 day — never the full upload. **Pricing: flat 10 credits per song.** Estimate via [`POST /v1/cost`](/api-reference/models/estimate-the-cost-of-a-request) with `{"model": "music-genre"}`. Charged on success only — a classifier failure costs nothing. ## OpenAPI ````yaml /openapi.yaml post /classifications/music-genre openapi: 3.1.0 info: contact: email: support@budgetpixel.com name: BudgetPixel Support description: > The BudgetPixel developer API for programmatic image, video, music and sound-effect generation. Generation is **asynchronous**: you create a job, then poll its status until it reaches a terminal state (`succeeded` / `failed`). You are charged in credits only on success — never for failures, timeouts, or content blocked before generation. **Authentication.** All requests require an API key sent as a bearer token: Authorization: Bearer bpx_live_xxx Create and manage keys from your BudgetPixel account dashboard. The developer API is available on **every paid plan**. On the **Free** plan, API keys can call one endpoint: `GET /v1/stock/images`, the free stock image library search. **Pricing.** API usage is metered in credits at each model's published price (see `GET /v1/models`), and your plan's model discounts and active promotions apply to API charges exactly as they do on the web — `POST /v1/cost` quotes your discounted price. Pro and Ultra plans include a daily free-models allowance (a shared pool of free generations per day across qualified image models such as FLUX 2 Klein and Qwen-Image) that covers API requests too — the standard price applies once the day's pool is used. Other promotional free daily generations remain web/app-only. Failed generations are never charged. **Rate limits.** Requests are limited per minute: **600 requests/min per API key** and **1200 requests/min per source IP** (defaults; subject to tuning). Every response carries `X-RateLimit-Limit`, `X-RateLimit-Remaining`, and `X-RateLimit-Reset` (seconds until the window resets). Exceeding a limit returns HTTP `429` with a `Retry-After` header — wait that long before retrying. Rejected requests still count against the window, so a tight retry loop keeps you limited; back off instead. Generation jobs additionally have a per-plan concurrency cap (the same one as the web workshop), independent of these request limits. `POST /v1/uploads` also has a dedicated **60 uploads/min per account** cap (it's free/unmetered) on top of these limits. title: BudgetPixel API version: '2026-06-20' servers: - description: Production url: https://api.budgetpixel.com/v1 security: - ApiKeyAuth: [] tags: - description: Account and credit balance name: Account - description: Discover available models and pricing name: Models - description: Upload input media for image/video generation name: Uploads - description: Image job status name: Images - description: FLUX image models name: Black Forest Labs - description: SeeDream image models name: Bytedance - description: Video job status name: Videos - description: Kuaishou Kling video models name: Kling - description: SeeDance video models name: ByteDance (SeeDance) - description: Music and sound-effect job status name: Audios - description: Music generation models name: Music - description: Text-to-sound-effect models (priced per second) name: Sound Effects - description: Format conversion for images, video, and audio name: Conversions - description: Publish posts to your BudgetPixel feed and enter clan themes name: Social - description: Content moderation — NSFW rating and CSAM detection name: Moderation - description: Content classification — music genre detection name: Classification - description: >- Search the free stock image library — available on every plan, including Free name: Stock Images paths: /classifications/music-genre: post: tags: - Classification summary: Classify a song's music genre description: > Classify one song into BudgetPixel's canonical music genre taxonomy — the same classifier that powers the site's music gallery. **Synchronous**: the response carries the genre plus style/mood tags and a confidence score. **Input**: one song (`audio`), max **20 MB** and **7 minutes**, as MP3, WAV, OGG, M4A, or FLAC. Accepts a public URL, an uploaded-file URL from [`POST /v1/uploads`](/api-reference/files/upload-input-media), a data URI, or raw base64. Tip: a 7-minute WAV exceeds 20 MB — use MP3 for long tracks. The classifier listens to a ~30-second excerpt sampled from ~25% into the track (the `clip` field in the response tells you the exact window). Only that excerpt is retained — privately, for ~1 day — never the full upload. **Pricing: flat 10 credits per song.** Estimate via [`POST /v1/cost`](/api-reference/models/estimate-the-cost-of-a-request) with `{"model": "music-genre"}`. Charged on success only — a classifier failure costs nothing. operationId: classifyMusicGenre requestBody: content: application/json: schema: properties: audio: description: >- One song (public URL, uploaded-file URL, data URI, or raw base64). Max 20 MB and 7 minutes. MP3/WAV/OGG/M4A/FLAC. type: string required: - audio type: object required: true responses: '200': content: application/json: schema: properties: clip: description: The excerpt the classifier heard. properties: duration_seconds: type: number start_seconds: type: number type: object confidence: description: Classifier confidence, 0-1. type: number credits_charged: type: integer genre: description: >- Canonical genre, e.g. `Electronic & Dance`. One of the site's music genres. type: string genre_slug: description: URL-safe slug of the genre, e.g. `electronic-and-dance`. type: string id: description: Classification request id (audit reference). type: string mood: description: One short mood phrase. type: string tags: description: 3-6 style/mood/instrument tags. items: type: string type: array type: object description: The classification. '400': $ref: '#/components/responses/BadRequest' '401': $ref: '#/components/responses/Unauthorized' '402': content: application/json: schema: $ref: '#/components/schemas/Error' description: Insufficient credits. '429': $ref: '#/components/responses/TooManyRequests' components: responses: BadRequest: content: application/json: schema: oneOf: - $ref: '#/components/schemas/Error' - $ref: '#/components/schemas/ModerationBlocked' description: >- The request was malformed, referenced an unavailable model, or was blocked by input content moderation (moderation blocks carry a `restriction_reason` — see ModerationBlocked). Unauthorized: content: application/json: schema: $ref: '#/components/schemas/Error' description: Missing or invalid API key. TooManyRequests: content: application/json: schema: $ref: '#/components/schemas/Error' description: Rate or queue limit reached. Retry after a short delay. schemas: Error: properties: error: properties: code: description: Stable machine-readable code. example: model_not_available type: string message: type: string type: description: Error category. example: invalid_request_error type: string required: - type - code - message type: object required: - error type: object ModerationBlocked: description: >- Returned (with HTTP 400) when the input content moderation gate blocks a generation request. The block is a property of the request's prompt or input media — reword the prompt or change the input and retry. Branch on `restriction_reason`, which is stable and machine-readable. properties: error: description: Human-readable explanation of the block. type: string restriction_reason: description: Stable machine-readable block reason. enum: - input_csam - input_explicit_adult - input_upload_nudity - input_celebrity_likeness - strict_model_nsfw type: string required: - error - restriction_reason type: object securitySchemes: ApiKeyAuth: bearerFormat: bpx_live_* description: 'API key as a bearer token: Authorization: Bearer bpx_live_xxx' scheme: bearer type: http ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.