> ## Documentation Index > Fetch the complete documentation index at: https://docs.omniall.ai/llms.txt > Use this file to discover all available pages before exploring further. # Generations > OpenAI-compatible image generation. **Path:** `POST https://api.omniall.ai/v1/images/generations` General entry. `image` may be a single URL/Base64 or a **string array** (multi-reference). With references, some channels route to `/v1/images/edits` or Chat bridge. Gemini native: `generateContent`. ## OpenAPI ````yaml openapi/xgapi-public.yaml POST /v1/images/generations openapi: 3.0.3 info: title: Omniall AI Public API description: >- Omniall AI public API. Website: https://omniall.ai — API host: https://api.omniall.ai — Model Square: https://omniall.ai/pricing version: 1.1.0 servers: - url: https://api.omniall.ai description: Production security: - bearerAuth: [] tags: - name: Models description: List models available to your API key. - name: ChatGPT Chat Completions x-group: ChatGPT description: OpenAI Chat Completions (`POST /v1/chat/completions`). - name: Responses description: OpenAI Responses API (`POST /v1/responses`). - name: Claude description: Anthropic Messages API (`POST /v1/messages`). - name: Gemini description: Google Gemini generateContent / streamGenerateContent. - name: Images description: >- Image generation (OpenAI Images), vendor guides, and Midjourney proxy APIs. - name: Video description: Async video tasks. - name: Audio description: Speech and related audio APIs. - name: Rerank description: Document reranking. paths: /v1/images/generations: post: tags: - Images summary: Create image (generations) description: >- OpenAI-compatible image generation. **Path:** `POST https://api.omniall.ai/v1/images/generations` General entry. `image` may be a single URL/Base64 or a **string array** (multi-reference). With references, some channels route to `/v1/images/edits` or Chat bridge. Gemini native: `generateContent`. operationId: createImageGeneration requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/ImageRequest' examples: text_to_image: summary: Text-to-image value: model: gpt-image-2 prompt: A calm studio workspace with soft daylight 'n': 1 size: 1024x1024 multi_reference: summary: Text-to-image · multi-reference value: model: gemini-3.1-flash-image-preview prompt: >- Match the style and palette of these references in one product poster image: - https://example.com/ref-style.jpg - https://example.com/ref-layout.jpg aspect_ratio: '16:9' 'n': 1 image_to_image: summary: Image-to-image value: model: gpt-image-2 prompt: Keep the subject, replace the background with a sunset beach image: https://example.com/reference.jpg 'n': 1 size: 1024x1024 responses: '200': description: Image generation result content: application/json: schema: $ref: '#/components/schemas/ImageResponse' example: created: 1710000000 data: - url: https://example.com/image.png '400': description: Invalid request content: application/json: schema: $ref: '#/components/schemas/OpenAIErrorResponse' '401': description: Unauthorized content: application/json: schema: $ref: '#/components/schemas/OpenAIErrorResponse' '429': description: Rate limited content: application/json: schema: $ref: '#/components/schemas/OpenAIErrorResponse' '500': description: Upstream/gateway error content: application/json: schema: $ref: '#/components/schemas/OpenAIErrorResponse' components: schemas: ImageRequest: type: object required: - model - prompt description: >- OpenAI-compatible image generation body (`POST /v1/images/generations`). Maps to gateway `dto.ImageRequest`. Works for GPT-Image, DALL·E, Flux, Grok Imagine, Seedream/Jimeng image channels, and many Gemini image models when routed to this path. properties: model: type: string description: >- Image model id from Model Square / `GET /v1/models`. Examples: `gpt-image-1`, `gpt-image-2`, `dall-e-3`, `flux-pro`, `grok-imagine-image`, `doubao-seedream-5-0-pro-260628`, `gemini-2.5-flash-image`. example: gpt-image-2 prompt: type: string description: >- Text description of the image to generate. Be specific about subject, style, lighting, and composition. example: A calm studio workspace with soft daylight 'n': type: integer minimum: 1 maximum: 128 description: >- How many images to generate. Cost usually scales with `n`. Some models only allow `n=1`. default: 1 size: type: string description: >- Output size as pixel string (e.g. `1024x1024`, `2048x1152`, `3840x2160`, `auto`), or use `aspect_ratio` with `quality`/`image_size` (1K/2K/4K). See the GPT-Image ratio table for common aspect ratios (3:1 through 1:3). Custom sizes: max side ≤ 3840, multiples of 16, aspect ratio ≤ 3:1. example: 1024x1024 quality: type: string description: >- Quality tier. GPT-Image commonly: `low` / `medium` / `high` / `auto`; some models also use `1K` / `2K` / `4K` (see ratio table). example: high aspect_ratio: type: string description: >- Aspect ratio, e.g. `1:1`, `16:9`, `9:16`, `3:2`, `4:3`, `21:9`, `3:1`, `1:3`. Combined with 1K/2K/4K tiers, see the GPT-Image ratio table for pixel sizes. example: '1:1' enum: - '3:1' - '21:9' - '16:9' - '3:2' - '4:3' - '1:1' - '3:4' - '2:3' - '9:16' - '1:3' - '4:5' - '5:4' image_size: type: string description: >- Provider-specific image size field (passed through; not rewritten into `resolution`). resolution: type: string description: >- Provider-specific resolution field (passed through independently from `image_size`). response_format: type: string enum: - url - b64_json description: >- Return image URL(s) or Base64 JSON. Default often `url` when supported. style: description: >- Style hint for models that support it (e.g. DALL·E `vivid` / `natural`). background: description: >- Background control for models that support transparent/opaque backgrounds (e.g. GPT-Image). moderation: description: Moderation level when the model supports it. output_format: description: Output file format when supported (e.g. `png`, `jpeg`, `webp`). output_compression: description: Compression level for formats that support it. partial_images: description: >- Partial/streaming image options when the model supports progressive output. stream: type: boolean description: >- Request streaming image events when the upstream model supports it (e.g. some GPT-Image streams). watermark: type: boolean description: Whether to request a watermark when the provider supports this flag. image: oneOf: - type: string description: Single reference URL, Base64, or data URI. - type: array items: type: string description: Array of reference URLs / Base64 strings (multi-reference). description: >- Optional reference image(s). Single URL, Base64, `data:image/...;base64,...`, or a **string array** of references. Prefer `/v1/images/edits` for full edit/inpaint flows. user: description: Opaque end-user id for abuse monitoring. extra_fields: description: >- Reserved/extra JSON fields. Prefer documented top-level fields when available. ImageResponse: type: object description: OpenAI-compatible image response. properties: created: type: integer description: Unix timestamp when the image job completed. data: type: array description: Generated image payloads. items: type: object properties: url: type: string description: >- Temporary HTTPS URL of the image (download promptly; may expire). b64_json: type: string description: Base64-encoded image bytes when `response_format=b64_json`. revised_prompt: type: string description: Prompt rewritten by the model (e.g. DALL·E), if any. OpenAIErrorResponse: type: object description: OpenAI-style error envelope returned on auth/request failures. required: - error properties: error: type: object required: - message - type properties: message: type: string description: >- Human-readable error. The gateway may append a request id for support. type: type: string description: Error type, commonly `new_api_error`. example: new_api_error code: type: string description: >- Optional machine-readable code (e.g. `access_denied`). May be an empty string. description: Error object. securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: API Key description: 'Use Authorization: Bearer sk-... from https://omniall.ai/dashboard' ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.