feat: add density transformation parameter

src/constants/supportedTransforms.ts

@@ -56,6 +56,7 @@ export const supportedTransforms: { [key: string]: string } = {
   lossless: "lo",
   colorProfile: "cp",
   metadata: "md",
+  density: "dn",
   opacity: "o",
   trim: "t",
   zoom: "z",

src/interfaces/shared.ts

@@ -1420,7 +1420,7 @@ export interface Transformation {
    *
    * - `co-color` - Color to apply (e.g., `red`, `blue`, `FF0022`). Default is gray
    *   color.
-   * - `in-intensity` - Intensity of the color (0-100). Default is 35. See
+   * - `in-intensity` - Intensity of the color (0-100). Default is 100. See
    *   [Colorize](https://imagekit.io/docs/effects-and-enhancements#colorize---e-colorize).
    */
   colorize?: string;
@@ -1468,6 +1468,16 @@ export interface Transformation {
    */
   defaultImage?: string;
 
+  /**
+   * Sets the output image density in dots per inch (DPI). Accepts an integer from 1
+   * to 1200 or an arithmetic expression using the `idn` variable, such as
+   * `idn_mul_2`. For raster images, this updates density metadata without changing
+   * dimensions. For vector images, it controls the DPI used during rasterization.
+   * Cannot be used inside layers. See
+   * [Density](https://imagekit.io/docs/image-optimization#density---dn).
+   */
+  density?: number | string;
+
   /**
    * Distorts the shape of an image. Supports two modes:
    *

test-app/tests/basic.spec.ts

@@ -1255,6 +1255,7 @@ test.describe("URL generation", () => {
                     trim: 5,
                     metadata: true,
                     colorProfile: true,
+                    density: 72,
                     defaultImage: "/folder/file.jpg/",
                     dpr: 3,
                     x: 10,
@@ -1297,7 +1298,7 @@ test.describe("URL generation", () => {
         });
 
         expect(url).toBe(
-            `https://ik.imagekit.io/test_url_endpoint/test_path.jpg?tr=h-300,w-400,ar-4-3,q-40,c-force,cm-extract,fo-left,f-jpeg,r-50,bg-A94D34,b-5-A94D34,rt-90,bl-10,n-some_name,pr-true,lo-true,t-5,md-true,cp-true,di-folder@@file.jpg,dpr-3,x-10,y-20,xc-30,yc-40,fl-h,o-0.8,z-2,vc-h264,ac-aac,so-5,eo-15,du-10,sr-1440_1080,e-grayscale,e-upscale,e-retouch,e-genvar,e-dropshadow,e-changebg-prompt-car,e-edit-prompt-make it vintage,e-bgremove,e-contrast,e-shadow-bl-15_st-40_x-10_y-N5,e-sharpen-10,e-usm-2-2-0.8-0.024,e-gradient-from-red_to-white,orig-true,pg-2_4,h-200,w-300,l-image,i-logo.png,l-end,cr-FF0000_50_00FF00,e-colorize-co-red_in-35,e-distort-p-50_50_150_50_150_150_50_150`
+            `https://ik.imagekit.io/test_url_endpoint/test_path.jpg?tr=h-300,w-400,ar-4-3,q-40,c-force,cm-extract,fo-left,f-jpeg,r-50,bg-A94D34,b-5-A94D34,rt-90,bl-10,n-some_name,pr-true,lo-true,t-5,md-true,cp-true,dn-72,di-folder@@file.jpg,dpr-3,x-10,y-20,xc-30,yc-40,fl-h,o-0.8,z-2,vc-h264,ac-aac,so-5,eo-15,du-10,sr-1440_1080,e-grayscale,e-upscale,e-retouch,e-genvar,e-dropshadow,e-changebg-prompt-car,e-edit-prompt-make it vintage,e-bgremove,e-contrast,e-shadow-bl-15_st-40_x-10_y-N5,e-sharpen-10,e-usm-2-2-0.8-0.024,e-gradient-from-red_to-white,orig-true,pg-2_4,h-200,w-300,l-image,i-logo.png,l-end,cr-FF0000_50_00FF00,e-colorize-co-red_in-35,e-distort-p-50_50_150_50_150_150_50_150`
         );
     });
 });

test-app/tests/buildTransformationString.spec.ts

@@ -24,4 +24,14 @@ test.describe("buildTransformationString", () => {
     );
     expect(result).toBe("l-text,i-Hello,l-end");
   });
+
+  test("should generate a transformation string for density as a number", async ({ page }) => {
+    const result = await page.evaluate(() => (window as any).buildTransformationString([{ density: 72 }]));
+    expect(result).toBe("dn-72");
+  });
+
+  test("should generate a transformation string for density as an arithmetic expression", async ({ page }) => {
+    const result = await page.evaluate(() => (window as any).buildTransformationString([{ density: "idn_mul_2" }]));
+    expect(result).toBe("dn-idn_mul_2");
+  });
 });