# Chatgpt Imagegen

> Generate and edit images with OpenAI's GPT Image models (gpt-image-2 default, gpt-image-1.5/1/1-mini fallbacks). Text-to-image, image editing/inpainting with mask, multi-image composition, transparent backgrounds, branded photo/logo/mockup generation. Up to 3840px, PNG/JPEG/WebP, low/medium/high quality. Use for ChatGPT/OpenAI/DALL-E image generation.

- Skill: `buzzmatic/chatgpt-imagegen` (Agent Skill, multi-file: 6 files)
- Install (CLI): `npx skillmds@latest add buzzmatic/chatgpt-imagegen`
- Raw SKILL.md: https://api.skillmd.com/api/skills/buzzmatic/chatgpt-imagegen/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Design & Media
- Author: Buzzmatic (https://skillmd.com/u/buzzmatic)
- Updated: 2026-09-22
- Page: https://skillmd.com/skills/buzzmatic/chatgpt-imagegen

---


# ChatGPT Image Generation (OpenAI Image API)

Generate and edit images via the OpenAI Image API using GPT Image models. The
`OPENAI_API_KEY` is loaded automatically from the project root `.env`; no
manual export is required.

## Default model

Always use `gpt-image-2` unless the user explicitly asks for a different model.
The full list:

| Model | Notes |
|-------|-------|
| `gpt-image-2` | **Default.** Latest, highest quality, flexible resolutions, high-fidelity edits. |
| `gpt-image-1.5` | Older flagship — use only on explicit request. |
| `gpt-image-1` | Legacy — use only on explicit request. |
| `gpt-image-1-mini` | Cheap/fast — use when the user asks for thumbnails or bulk drafts. |

## Quick start

```bash
# Text → image (defaults: gpt-image-2, auto size, png)
python skills/chatgpt-imagegen/scripts/generate_image.py \
  "a kawaii red panda wearing sunglasses" panda.png

# Landscape, high quality
python skills/chatgpt-imagegen/scripts/generate_image.py \
  "epic mountain sunrise" mountain.png --size landscape --quality high

# Edit an existing image (inpaint via mask)
python skills/chatgpt-imagegen/scripts/edit_image.py \
  "replace sky with stars" input.png out.png --mask sky_mask.png

# Compose from multiple references
python skills/chatgpt-imagegen/scripts/edit_image.py \
  "group photo of these three people in a modern office" group.png \
  --image person1.png --image person2.png --image person3.png
```

Both scripts return base64 image data and write it to disk. For `n>1` the
files become `name_1.png`, `name_2.png`, etc.

## Parameters

### `--size`

`gpt-image-2` accepts any custom resolution under these constraints: each edge
≤ 3840px and a multiple of 16, total pixels between 655,360 and 8,294,400,
aspect ratio ≤ 3:1.

The CLI accepts:

| Value | Meaning |
|-------|---------|
| omitted / `auto` | Let the model pick |
| `square` | 1024×1024 |
| `landscape` | 1536×1024 |
| `portrait` | 1024×1536 |
| `4k` | 3840×2160 |
| `WxH` | Custom, e.g. `2048x1280` |

### `--quality`

`auto` (default), `low`, `medium`, `high`. Pricing scales steeply — use `low`
for thumbnails/drafts, `high` only for final deliverables.

| Quality | Cost per image (approx., 1024² range) |
|---------|---------------------------------------|
| low | $0.005–$0.006 |
| medium | $0.041–$0.053 |
| high | $0.165–$0.211 |

### `--output-format` and `--output-compression`

`png` (default), `jpeg`, `webp`. Pass `--output-compression 0-100` for JPEG/WebP
to trade off quality for file size.

The output extension is taken from the file path you pass; pass
`--output-format` only if you want to override it.

### `--background`

`opaque` | `automatic` | `transparent`. Note: gpt-image-2 does **not** support
`transparent` — use gpt-image-1 or gpt-image-1.5 if a transparent background
is required (and use PNG or WebP, not JPEG).

### `--moderation`

`auto` (default) | `low`. Pass `low` for less restrictive filtering on
brand/marketing content.

### `--n`

Number of images per call. Files are saved as `name_1.ext`, `name_2.ext`, …

## Editing modes

`edit_image.py` covers three patterns:

1. **Whole-image edit** — pass one input image plus a prompt. The model
   regenerates the entire image guided by the original.
2. **Mask inpainting** — add `--mask mask.png`. The mask must be a PNG with
   an alpha channel; transparent pixels mark the region to regenerate, opaque
   pixels are kept.
3. **Multi-image composition** — pass multiple `--image` flags (or one
   positional + multiple `--image`). The model composes a new image using
   all references. Useful for combining people, products, or styles.

`gpt-image-2` always uses high input fidelity; the `--input-fidelity` flag
exists for older models.

## Prompting guidance

Keep prompts descriptive and visual — avoid passive negations ("no clouds")
and prefer positive descriptions ("clear blue sky").

| Use case | Pattern |
|----------|---------|
| Photorealistic | "Photorealistic close-up portrait, 85mm lens, golden-hour light, shallow depth of field, …" |
| Stylized illustration | "Kawaii sticker, bold black outlines, cel-shading, white background, …" |
| Logo with text | Spell text in quotes: "logo with the text 'Acme' in clean sans-serif…" |
| Product mockup | "Studio photo on polished concrete, three-point softbox, 45° angle, …" |
| Marketing banner | Specify aspect ratio, focal point, copy-safe area: "wide banner with empty space on the right for headline copy" |

GPT Image silently rewrites prompts; the scripts surface the rewritten version
as `revised_prompt` so you can iterate on what the model actually saw.

## Common tasks

### Logo with transparent background

Transparent output is gpt-image-1.5 / gpt-image-1 only:

```bash
python scripts/generate_image.py \
  "minimal flat logo: orange spark icon next to the word 'Acme' in bold sans-serif, on a clean canvas" \
  logo.png \
  --model gpt-image-1.5 --background transparent --output-format png --quality high
```

### High-resolution hero image

```bash
python scripts/generate_image.py \
  "panoramic city skyline at dusk, cinematic colour grading" \
  hero.jpeg \
  --size 3840x1280 --quality high --output-format jpeg --output-compression 92
```

### Variation set for A/B testing

```bash
python scripts/generate_image.py \
  "social card for a SaaS launch announcement" \
  variant.png --n 4 --size landscape --quality medium
```

### Mask inpainting

Build the mask in any editor (e.g. Pillow, Photoshop) with the area to
regenerate set to fully transparent and the rest opaque.

```bash
python scripts/edit_image.py \
  "replace the sky with a clear starfield with the milky way" \
  photo.png photo_starry.png --mask sky_mask.png --quality high
```

## Output

Both scripts print saved file paths and any `revised_prompt`. Pass `--json`
for a machine-readable result:

```json
{
  "model": "gpt-image-2",
  "files": ["panda.png"],
  "revised_prompts": ["A kawaii red panda wearing sunglasses..."],
  "usage": {
    "total_tokens": 4321,
    "input_tokens": 12,
    "output_tokens": 4309
  }
}
```

## Troubleshooting

**"OPENAI_API_KEY not set"** — confirm the key is in the project root `.env`
file. The scripts auto-load it from there.

**"You may need to complete the API Organization Verification"** — gpt-image-*
models require org verification. Complete it in the OpenAI dashboard.

**"Invalid size"** — custom dimensions must be multiples of 16, ≤ 3840 per
edge, with total pixels in [655,360, 8,294,400] and aspect ratio ≤ 3:1.

**Latency** — high-quality 4K images can take up to 2 minutes. Don't time out
the call; use `low`/`medium` while iterating on prompt language.

**Transparent background ignored** — gpt-image-2 does not support transparent.
Switch to `--model gpt-image-1.5 --background transparent`.

**Garbled text in image** — text rendering is improved but still imperfect.
Quote the text explicitly, keep it short, and re-roll if needed.

## Comparison with sibling skills

- **gemini-imagegen** — Google's Nano Banana Pro. Use when the user explicitly
  asks for Gemini, or needs Google Search grounding inside the image.
- **kie-ai** — third-party gateway with GPT-4o, Flux Kontext etc. Use when
  the user names kie.ai or wants a non-OpenAI GPT image model.
- **chatgpt-imagegen** (this) — first-party OpenAI Image API. Default for any
  generic "ChatGPT image" / "OpenAI image" / "DALL-E successor" request.