Popiai-skill/content-creation/video-prompting/references/models/image-models/prompting.md

Image Generation Models - Prompting Guide

This guide covers all available image generation models, helping you choose the right model and write optimal prompts.

Model Selection Quick Reference

Need	Recommended Model	Tool Name
General text-to-image / image editing	Gemini (default)	nano_banana_image_generation
Batch image generation	Gemini Batch	nano_banana_batch_image_generation_v2
Text embedded in images	Qwen Wanxiang	qwen_image_generation
Style transfer / editing	FLUX Kontext	kontext_image_generation
Face / character reference	Kling	kling_image_generation
Creative illustration / Logo / transparent background	OpenAI GPT-Image	openai_image_generation
Artistic quality	Midjourney	midjourney_image_generation
Many reference images (up to 14)	Seedream	seedream_image_generation

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Gemini (nano_banana)

Default image model with the strongest overall capabilities.

Model Variants

Variant	Model ID	Features
nano_banana	gemini-2.5-flash-image	Fast, good for iteration
nano_banana_2	gemini-3-pro-image-preview	High quality
nano_banana_2_flash	gemini-3.1-flash-image-preview	Default, balances speed and quality

Prompt Style

Natural language descriptions, like talking to an artist:

A serene Japanese garden in autumn, with a wooden bridge over a koi pond.
Red and golden maple leaves float on the water surface. Soft morning mist
rises from the pond. Shot in the style of a landscape photograph, natural
lighting, shallow depth of field focusing on the bridge.

Image Editing

Provide reference images via image_paths, then describe the desired changes in the prompt:

image_paths: [original.jpg]
prompt: "Change the background to a sunset beach scene, keep the person and their pose exactly the same"

Resolution

Supports 1K / 2K / 4K, default 2K. 2K is sufficient for video first frames.

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Qwen Wanxiang (qwen)

Best choice for embedding text in images. Only supports image editing (reference image required).

Use Cases

• Adding text titles to images
• Modifying existing text in images
• Poster / cover creation

Prompt

image_paths: [background.jpg]
prompt: "Add the text 'Brightest Star in the Night Sky' in elegant calligraphy style at the center of the image, white text with subtle glow effect"

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FLUX Kontext (kontext)

Best choice for style transfer and image editing.

Strengths

• Converting photos to specific art styles
• Changing art style while maintaining composition
• Multi-image reference fusion

Prompt

image_paths: [photo.jpg]
prompt: "Transform this photo into Studio Ghibli anime style, maintain the same composition and character pose, soft watercolor textures, warm pastel colors"

Aspect Ratios

Supports a rich set of aspect ratios: 1:1, 16:9, 9:16, 3:2, 2:3, 4:3, 3:4, 4:5, 5:4, 21:9, 7:4, 4:7

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Kling (kling)

Best choice for face and character reference generation.

Reference Modes

Mode	Use Case
subject	Preserves overall appearance (clothing, pose, style)
face	Preserves facial features only (can change outfit, scene)

Prompt

# Face mode: Keep face, change scene
image_path: face_reference.jpg
reference_type: face
prompt: "A woman in a traditional red qipao standing in a lantern-lit ancient Chinese street at night, full body shot, elegant pose, cinematic lighting"

# Subject mode: Preserve overall appearance
image_path: character_reference.jpg
reference_type: subject
prompt: "The same person standing on a rooftop at sunset, wind blowing through their hair, dramatic sky background, cinematic wide shot"

Batch Generation

kling_batch_image_generation supports independent prompt, reference image, reference mode, and aspect ratio for each image.

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OpenAI GPT-Image (openai)

Best choice for creative illustrations, logos, and transparent backgrounds.

Special Capabilities

• Transparent background images (ideal for logos, stickers, UI elements)
• Creative concept visualization
• Abstract art

Prompt

prompt: "A minimalist logo of a phoenix rising from flames, clean vector style, bold lines, gradient from deep red to bright gold"
size: "1024x1024"
quality: "high"

Image Editing

image_paths: [original.jpg]
prompt: "Remove the background and make it transparent, keep only the main subject"

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Midjourney (midjourney)

Best choice for artistic quality and stylization.

Version Selection

Append version flag at the end of the prompt:

• --v 7: V7 (default), realistic and general purpose
• --niji 7: Niji7, anime/manga style

Core Parameters

Parameter	Function	Example
--ar	Aspect ratio	--ar 16:9
--sref	Style reference URL	--sref https://example.com/style.jpg
--cref	Character reference URL	--cref https://example.com/char.jpg
--cw	Character reference weight (0-100)	--cw 50

Prompt Style

Midjourney favors concise, evocative descriptions — no need to be overly verbose:

prompt: "ancient samurai meditating under cherry blossoms, moonlit courtyard, atmospheric fog, cinematic lighting, dramatic shadows --ar 16:9 --v 7"

Reference Images

Provide local reference images via image_paths:

image_paths: [reference.jpg]
prompt: "a warrior in similar armor style standing on a cliff overlooking a vast ocean, epic scale, golden hour --ar 16:9 --v 7"

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Seedream (seedream)

Supports the most reference images — version 4.5 supports up to 14 reference images.

Model Selection

Model	Features
doubao-seedream-4-0-250828	Standard version
doubao-seedream-4-5-251128	New version, supports up to 14 reference images

Ideal Use Cases

• Scenarios requiring many reference images to constrain style
• Multi-character consistency (provide multiple character reference images)
• Complex scene reconstruction

Prompt

image_paths: [ref1.jpg, ref2.jpg, ref3.jpg, ...]
prompt: "A group photo of these characters together in a modern office setting, natural lighting, professional photography style, everyone is smiling and looking at the camera"

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General Prompting Tips

1. Optimizing for Video First Frames

When generating images intended as video first frames:

✓ Character's mouth slightly open (helps with lip sync)
✓ Pose suggests motion (e.g., mid-step, mid-turn)
✓ Leave room for motion in the frame (don't push subject to edges)
✓ Avoid extreme perspective (video models struggle to maintain it)
✗ Don't generate overly static "passport photo" compositions

2. MV First Frame Batch Generation Strategy

1. Determine art style → select primary image generation model
2. Use Kling face mode to lock character facial consistency
3. Batch generate first frames for each scene with the selected model
4. Use Kontext to unify style (if inconsistencies exist)
5. After confirmation, send to video model for generation

3. Style Consistency

Tips for maintaining unified style across a set of images:

• Use the same style keyword suffix
• Use Midjourney --sref to lock style
• Use Kling face mode to lock character appearance
• Use Kontext with the same style reference image for all images
• In batch generation tools (Gemini batch / Kling batch), use the same style description suffix for each image