Duotone Image Generator
Map image shadows and highlights to two custom colors
Duotone Image Generator — what it does
Map an image's tonal range onto two colours: the darkest areas take your shadow colour, the lightest take your highlight colour, and everything between is interpolated. Duotone unifies photographs of wildly different origins into one visual language, which is why editorial and brand systems lean on it so heavily.
When this tool helps
- Giving a set of mismatched stock photos a consistent brand-coloured treatment.
- Creating a section background where a photo must sit behind text without competing with it.
- Producing a styled header image for an article or presentation.
How to use it
- Choose the image.
- Pick the shadow colour and the highlight colour.
- Process the duotone conversion.
- Download the result.
Accuracy, limits, and good practice
- The two colours need real contrast in lightness, not just different hues, or the image flattens into an unreadable mush.
- A dark brand colour for shadows and a very light neutral for highlights is the safest recipe and reads well behind white text.
- Photos with a clear subject and simple background survive duotone best; busy scenes lose their structure once colour information is removed.
Frequently asked questions
Is this the same as tinting?
No. A tint shifts every pixel toward one colour; duotone maps the shadow-to-highlight ramp across two colours, keeping tonal separation.
Can I use three colours?
This tool is two-colour by design. Tritone effects need an image editor with gradient map control.
Why does my image look flat?
The two colours are probably too close in lightness. Push the shadow darker and the highlight lighter.
Related tools on this site
- Image Annotation Tool — Add text, rectangles, and arrows to an image
- Image EXIF Viewer — Inspect image dimensions and available camera metadata
- Rounded Image & Border — Add rounded corners, background, and a custom border
Everything above runs inside this page. Duotone Image Generator needs no account, no upload, and no server round trip — close the tab and nothing is left behind.
雙色調圖片生成器能做什麼
把圖片的明暗範圍映射到兩個顏色：最暗處取你的陰影色、最亮處取你的高光色，中間依比例內插。雙色調能把來源天差地遠的照片統一成同一種視覺語言，這也是編輯設計與品牌系統重度依賴它的原因。
什麼時候用得上
- 為一組風格不一的圖庫照片，套上一致的品牌色處理。
- 當照片必須襯在文字後方又不能搶戲時，用它做區塊背景。
- 為文章或簡報製作風格化的頁首圖。
使用步驟
- 選擇圖片。
- 挑選陰影色與高光色。
- 執行雙色調轉換。
- 下載結果。
精確度、限制與實務建議
- 兩個顏色必須在明度上真的拉開，光是色相不同不夠，否則畫面會糊成一片。
- 深色品牌色當陰影、極淺中性色當高光，是最保險的配方，襯白字也好看。
- 主體清楚、背景單純的照片最禁得起雙色調；畫面雜亂的場景一旦抽掉色彩資訊就失去結構。
常見問題
這和上色調（tint）一樣嗎？
不一樣。上色調是把每個像素都推向同一色；雙色調是把「暗到亮」的階梯映射到兩色，保留明暗層次。
可以用三個顏色嗎？
本工具設計為雙色。三色效果需要具備漸層映射功能的影像編輯器。
為什麼畫面看起來很平？
通常是兩色明度太接近。請把陰影色調更暗、高光色調更亮。
本站相關工具
- 圖片標註工具 — 在圖片加入文字、矩形與箭頭
- 圖片 EXIF 檢視器 — 查看圖片尺寸與可用的相機中繼資料
- 圖片圓角與邊框 — 加入圓角、背景與自訂邊框
以上步驟全部在這個頁面內完成，雙色調圖片生成器 不需要註冊、不上傳檔案、也不經過伺服器，關閉分頁後不會留下任何資料。