⚾ Replace Buffer with Uint8Array

README.md

@@ -51,7 +51,7 @@ async main() {
     });
 
     // Save the PNG image to the output folder
-    await fs.writeFile(`output/${page.number}.png`, image.data);
+    await fs.writeFile(`output/${page.number}.png`, Buffer.from(image.data));
   }
 
   // Do not forget to destroy the document and the library

docs/docs/02-render-pdf.md

@@ -106,15 +106,15 @@ console.log(image.data); // Bitmap image data as a buffer
 
 #### render: custom render function
 
-You can also pass a custom render function as the `render` option. It should be a function that accepts a `RenderPageOptions` object and returns a `Promise<Buffer>` object. You can use it to render to any image format:
+You can also pass a custom render function as the `render` option. It should be a function that accepts a `RenderPageOptions` object and returns a `Promise<Uint8Array>` object. You can use it to render to any image format:
 
 ```typescript
 import sharp from 'sharp';
 import { type PDFiumPageRenderOptions } from '@hyzyla/pdfium';
 
 const image = await page.render({
   scale: 3,
-  render: async (options: PDFiumPageRenderOptions): Promise<Buffer> => {
+  render: async (options: PDFiumPageRenderOptions): Promise<Uint8Array> => {
     return await sharp(options.data, {
       raw: {
         width: options.width,
@@ -170,7 +170,7 @@ async main() {
     });
 
     // Save the PNG image to the output folder
-    await fs.writeFile(`output/${page.number}.png`, image.data);
+    await fs.writeFile(`output/${page.number}.png`, Buffer.from(image.data));
   }
 
   // Do not forget to destroy the document and the library

docs/docs/03-extract-images-from-page.md

@@ -22,7 +22,7 @@ for (const page of document.pages()) {
       });
 
       // Save the PNG image to the output folder
-      await fs.writeFile(`output/${index}.png`, image.data);
+      await fs.writeFile(`output/${index}.png`, Buffer.from(image.data));
 
       index++;
     }
@@ -44,7 +44,7 @@ const page = document.getPage(0);
 const object = page.getObject(0);
 
 const image = await object.render({
-  render: async (options: PDFiumPageRenderOptions): Promise<Buffer> => {
+  render: async (options: PDFiumPageRenderOptions): Promise<Uint8Array> => {
     return await sharp(options.data, {
       raw: {
         width: options.width,

src/objects.ts

@@ -1,7 +1,7 @@
 import type * as t from "./vendor/pdfium";
 
 import { BYTES_PER_PIXEL, FPDFBitmap, FPDFPageObjectType } from "./constants";
-import { convertBitmapToImage } from "./utils";
+import { convertBitmapToImage, readUInt16LE } from "./utils";
 import type {
   PDFiumImageObjectRaw,
   PDFiumImageObjectRender,
@@ -93,7 +93,7 @@ export class PDFiumImageObject extends PDFiumObjectBase {
       throw new Error("Failed to get bitmap buffer.");
     }
 
-    const oData = Buffer.from(this.module.HEAPU8.slice(bufferPtr, bufferPtr + bufferSize));
+    const oData = this.module.HEAPU8.slice(bufferPtr, bufferPtr + bufferSize);
     this.module.wasmExports.free(bufferPtr);
 
     // Width and height of the image in pixels will be written to these pointers as 16-bit integers (2 bytes each):
@@ -106,12 +106,12 @@ export class PDFiumImageObject extends PDFiumObjectBase {
       throw new Error("Failed to get image size.");
     }
 
-    const widthBuffer = Buffer.from(this.module.HEAPU8.slice(widthPtr, widthPtr + 2));
-    const heightBuffer = Buffer.from(this.module.HEAPU8.slice(heightPtr, heightPtr + 2));
+    const widthBuffer = this.module.HEAPU8.slice(widthPtr, widthPtr + 2);
+    const heightBuffer = this.module.HEAPU8.slice(heightPtr, heightPtr + 2);
     this.module.wasmExports.free(sizePtr);
 
-    const width = widthBuffer.readUInt16LE();
-    const height = heightBuffer.readUInt16LE();
+    const width = readUInt16LE(widthBuffer)
+    const height = readUInt16LE(heightBuffer)
 
     const filtersCount = this.module._FPDFImageObj_GetImageFilterCount(this.objectIdx);
     const filters: string[] = [];
@@ -121,8 +121,9 @@ export class PDFiumImageObject extends PDFiumObjectBase {
       if (!this.module._FPDFImageObj_GetImageFilter(this.objectIdx, i, filterPtr, filterSize)) {
         throw new Error("Failed to get image filter.");
       }
-      const filterBuffer = Buffer.from(this.module.HEAPU8.slice(filterPtr, filterPtr + filterSize - 1));
-      const filter = filterBuffer.toString("utf8").trim();
+      const filterBuffer = this.module.HEAPU8.slice(filterPtr, filterPtr + filterSize - 1);
+      const filter = (new TextDecoder().decode(filterBuffer)).trim();
+
       this.module.wasmExports.free(filterPtr);
       filters.push(filter);
     }
@@ -178,7 +179,9 @@ export class PDFiumImageObject extends PDFiumObjectBase {
     const tBPP = BYTES_PER_PIXEL;
 
     // Create a new buffer for the target image and fill it with white color
-    const tData = Buffer.alloc(width * height * tBPP, 255);
+    const tData = new Uint8Array(width * height * tBPP);
+    // Fill the buffer with transparent white color
+    tData.fill(255);
 
     // Iterate over the rows of the original and target images
     for (let rowIndex = 0; rowIndex < height; rowIndex++) {

src/objects.types.ts

@@ -9,12 +9,12 @@ export type PDFiumImageObjectRenderParams = {
 export type PDFiumImageObjectRender = {
   width: number;
   height: number;
-  data: Buffer;
+  data: Uint8Array;
 };
 
 export type PDFiumImageObjectRaw = {
   width: number;
   height: number;
-  data: Buffer;
+  data: Uint8Array;
   filters: string[];
 };

src/page.ts

@@ -89,7 +89,7 @@ export class PDFiumPage {
     this.module._FPDFBitmap_Destroy(bitmap);
     this.module._FPDF_ClosePage(this.pageIdx);
 
-    const data = Buffer.from(this.module.HEAPU8.subarray(ptr, ptr + buffSize));
+    const data = this.module.HEAPU8.subarray(ptr, ptr + buffSize);
     this.module.wasmExports.free(ptr);
 
     const image = await this.convertBitmapToImage({
@@ -112,7 +112,7 @@ export class PDFiumPage {
     options: {
       render: PDFiumRenderFunction;
     } & PDFiumRenderOptions,
-  ): Promise<Buffer> {
+  ): Promise<Uint8Array> {
     return await convertBitmapToImage(options);
   }
 

src/page.types.ts

@@ -3,18 +3,18 @@ import type { PDFiumRenderFunction, PDFiumRenderOptions } from "./types";
 export type PDFiumPageRenderFunction = PDFiumRenderFunction;
 export type PDFiumPageRenderOptions = PDFiumRenderOptions;
 
-export type PDFiumPageRenderCallback = (options: PDFiumPageRenderOptions) => Promise<Buffer>;
+export type PDFiumPageRenderCallback = (options: PDFiumPageRenderOptions) => Promise<Uint8Array>;
 export type PDFiumPageRenderParams = {
   render: PDFiumPageRenderFunction;
 } & (
-  | {
+    | {
       scale: number;
     }
-  | {
+    | {
       width: number;
       height: number;
     }
-);
+  );
 
 export type PDFiumPageSize = {
   width: number;
@@ -26,5 +26,5 @@ export type PDFiumPageRender = {
   height: number;
   originalHeight: number;
   originalWidth: number;
-  data: Buffer;
+  data: Uint8Array;
 };

src/renderer/sharp.ts

@@ -1,6 +1,6 @@
 import type { PDFiumRenderOptions } from "../types";
 
-export async function renderBySharp(options: PDFiumRenderOptions): Promise<Buffer> {
+export async function renderBySharp(options: PDFiumRenderOptions): Promise<Uint8Array> {
   const { default: sharp } = await import("sharp");
   return await sharp(options.data, {
     raw: {

src/types.ts

@@ -1,9 +1,9 @@
 export type PDFiumRenderOptions = {
   width: number;
   height: number;
-  data: Buffer;
+  data: Uint8Array;
 };
 
-export type PDFiumRenderCallback = (options: PDFiumRenderOptions) => Promise<Buffer>;
+export type PDFiumRenderCallback = (options: PDFiumRenderOptions) => Promise<Uint8Array>;
 
 export type PDFiumRenderFunction = "sharp" | "bitmap" | PDFiumRenderCallback;

src/utils.ts

@@ -5,7 +5,7 @@ export async function convertBitmapToImage(
   options: {
     render: PDFiumRenderFunction;
   } & PDFiumRenderOptions,
-): Promise<Buffer> {
+): Promise<Uint8Array> {
   switch (options.render) {
     case "sharp":
       return await renderBySharp(options);
@@ -15,3 +15,8 @@ export async function convertBitmapToImage(
       return await options.render(options);
   }
 }
+
+
+export function readUInt16LE(buffer: Uint8Array, offset = 0): number {
+  return buffer[offset] | (buffer[offset + 1] << 8);
+}

test/index.test.ts

@@ -151,14 +151,14 @@ describe("PDFium", () => {
         const result = await document.getPage(0).render({
           scale: 1,
           render: async (options) => {
-            expect(options.data).toBeInstanceOf(Buffer);
+            expect(options.data).toBeInstanceOf(Uint8Array);
             expect(options.height).toBe(A4_SIZE.height);
             expect(options.width).toBe(A4_SIZE.width);
-            return Buffer.from("test");
+            return new TextEncoder().encode("test");
           },
         });
         expect(result).toEqual({
-          data: Buffer.from("test"),
+          data: new TextEncoder().encode("test"),
           height: A4_SIZE.height,
           width: A4_SIZE.width,
           originalHeight: A4_SIZE.height,
@@ -256,6 +256,7 @@ describe("PDFium", () => {
               const { data: image } = await imageObj.render({
                 render: "sharp",
               });
+              expect(image).toBeInstanceOf(Uint8Array);
               expect(image).toMatchImageSnapshot();
             }
           }