Gemini image overview

Common ways to call Gemini image models on Omniall AI:

Menu	Path	Notes
Generations	`POST /v1/images/generations`	OpenAI Images entry
Gemini native format	`POST /v1beta/models/{model}:generateContent`	Native `responseModalities` + `imageConfig`; image / PDF / short-video `inlineData`
Chat image generation	`POST /v1/chat/completions`	One Chat endpoint: text-to-image / image-to-image / multi-ref; Banana 2.1 also `file` (PDF) and `video_url`

Aspect ratio / resolution via extra_body.google.image_config (Chat) or generationConfig.imageConfig (native), e.g. aspect_ratio / aspectRatio, image_size / imageSize (1K / 2K / 4K). Pick model from the Model Square.

Banana 2.1 (`gemini-nano-banana-2.1`)

Supports text-to-image, image-to-image, plus PDF and short video reference generation.

Style	Reference input	Notes
Native `generateContent`	`parts[].inlineData`	`mimeType`: `image/*`, `application/pdf`, `video/mp4`; raw Base64 (no `data:` prefix)
Chat Completions	`image_url` / `file` / `video_url`	Gateway downloads URLs or decodes data URLs → upstream `inlineData`; PDF URL and video URL supported

Chat: PDF URL

{
  "model": "gemini-nano-banana-2.1",
  "stream": false,
  "extra_body": {
    "google": {
      "image_config": { "aspect_ratio": "3:2", "image_size": "1K" }
    }
  },
  "messages": [{
    "role": "user",
    "content": [
      { "type": "text", "text": "Read the PDF, list page info, then generate a white-background reference image." },
      {
        "type": "file",
        "file": {
          "filename": "reference.pdf",
          "file_data": "https://example.com/reference.pdf"
        }
      }
    ]
  }]
}

Chat: video URL

{
  "model": "gemini-nano-banana-2.1",
  "stream": false,
  "extra_body": {
    "google": {
      "image_config": { "aspect_ratio": "3:2", "image_size": "1K" }
    }
  },
  "messages": [{
    "role": "user",
    "content": [
      { "type": "text", "text": "Watch the video and generate a reference image in scene order." },
      { "type": "video_url", "video_url": "https://example.com/clip.mp4" }
    ]
  }]
}

Notes:

Pass video_url as a string, not { "url": "..." }
file requires both filename and file_data
URLs must be publicly downloadable; default download limit ~64MB; prefer short MP4 / small PDF
Full curl / native examples: Gemini native format and Chat image generation

Optional: Thinking levels

gemini-nano-banana-2.1 supports official Thinking. For typical integrations you can omit this config and use the default level.

Level	Notes
`minimal`	Lower latency, less thinking
`medium`	Default
`high`	More thinking effort; gains depend on the task

Field	Role
`thinkingLevel` / `thinking_level`	Thinking level (table above)
`includeThoughts` / `include_thoughts`	Whether to return thought text in the response; does not disable internal thinking

Usage may include reasoning_tokens / thoughtsTokenCount for thinking cost, regardless of whether thought text is returned. Native — under generationConfig.thinkingConfig:

{
  "generationConfig": {
    "responseModalities": ["TEXT", "IMAGE"],
    "imageConfig": { "imageSize": "1K", "aspectRatio": "3:2" },
    "thinkingConfig": {
      "thinkingLevel": "high",
      "includeThoughts": false
    }
  }
}

Chat — under extra_body.google.thinking_config (snake_case required):

{
  "model": "gemini-nano-banana-2.1",
  "messages": [{
    "role": "user",
    "content": [
      { "type": "text", "text": "Watch the video and generate a character-consistent reference image." },
      { "type": "video_url", "video_url": "https://example.com/clip.mp4" }
    ]
  }],
  "extra_body": {
    "google": {
      "image_config": { "aspect_ratio": "16:9", "image_size": "1K" },
      "thinking_config": {
        "thinking_level": "high",
        "include_thoughts": false
      }
    }
  }
}

Notes: In Chat use thinking_config / thinking_level — camelCase thinkingConfig is rejected. When parsing the response, walk all parts and skip items with thought: true before reading the image. Other model examples: gemini-3.1-flash-image-preview, gemini-3-pro-image-preview (per Model Square).

Overview

Models

Chat

Images

Video

Audio

Platform

Rerank

Overview

Gemini image overview

Banana 2.1 (`gemini-nano-banana-2.1`)

Chat: PDF URL

Chat: video URL

Optional: Thinking levels

​Gemini image overview

​Banana 2.1 (gemini-nano-banana-2.1)

​Chat: PDF URL

​Chat: video URL

​Optional: Thinking levels

Gemini image overview

Banana 2.1 (`gemini-nano-banana-2.1`)

Chat: PDF URL

Chat: video URL

Optional: Thinking levels