Gemini Image Generator

Workflow

1. Collect the user prompt and any images (local paths or URLs).
2. Infer the operation mode and translate parameters into CLI flags.
3. Run the appropriate script to generate or edit images.
4. Return the output file paths.

Defaults and Rules

• Default model:

  gemini-2.5-flash-image

  (CLI value

  flash

  ).
• Default aspect ratio:

  9:16

  .
• Default count:

  1

  (max

  3

  ).
• Default image size:

  1K

  , but only apply it for the Pro model.
• If the user specifies a size (

  1K|2K|4K

  ), switch to Pro (

  gemini-3-pro-image-preview

  ).
• If the user explicitly asks for Pro or higher quality, use Pro.
• If the user supplies multiple reference images (2+), switch to Pro.
• Logo overlay always uses Pro (even if the user asks for Flash).
• Only set

  --size

  when using Pro.

Allowed Values

• Aspect ratios:

  1:1

  ,

  2:3

  ,

  3:2

  ,

  3:4

  ,

  4:3

  ,

  4:5

  ,

  5:4

  ,

  9:16

  ,

  16:9

  ,

  21:9

  .
• Image sizes (Pro only):

  1K

  ,

  2K

  ,

  4K

  .
• Reference images (Pro): up to 14 total. Gemini guidance: up to 6 object images + up to 5 human images.

Script

Scripts

Text-to-image

python scripts/generate_image.py \
  --prompt "<user prompt>" \
  --aspect 9:16 \
  --count 1 \
  --model flash \
  --out-dir outputs

GEMINI_API_KEY

Image editing / image-to-image

python scripts/edit_image.py \
  --input /path/to/base.png \
  --prompt "<edit instructions>" \
  --reference /path/to/ref1.png \
  --reference https://example.com/ref2.png \
  --aspect 9:16 \
  --count 1 \
  --model flash \
  --out-dir outputs

Logo overlay

python scripts/logo_overlay.py \
  --base /path/to/base.png \
  --logo /path/to/logo.png \
  --aspect 9:16 \
  --count 1 \
  --model pro \
  --out-dir outputs

Examples

• Use defaults (flash, 9:16, count 1).
• Run:

  python scripts/generate_image.py --prompt "Generate a portrait of a dancer in a foggy forest."

• Use Pro with size 2K, aspect 16:9, count 3.
• Run:

  python scripts/generate_image.py --prompt "Make a 2K 16:9 cinematic still of a neon city" --aspect 16:9 --size 2K --count 3 --model pro

• Use edit script with Flash.
• Run:

  python scripts/edit_image.py --input /path/to/image.png --prompt "Remove the background and make it studio white."

• Use logo overlay script (Pro).
• Run:

  python scripts/logo_overlay.py --base /path/to/photo.png --logo /path/to/logo.png

Notes

• If the script fails with a missing module, install

  google-genai

  and retry.
• Dependencies live in

  scripts/requirements.txt

  (install with

  pip install -r scripts/requirements.txt

  ).
• Output files are written into the

  outputs/

  directory using timestamped names.
• For prompt best practices and templates, read

  references/prompt-guide.md

  .
• For logo-specific guidance, read

  references/logo-overlay.md

  .
• For edit/image-to-image guidance, read

  references/image-editing.md

  .
• For watermarking guidance, read

  references/watermarking.md

  .