@nova-slides/pdf-to-img
Version:
📃📸 Converts PDFs to images in nodejs
118 lines (117 loc) • 6.63 kB
JavaScript
;
var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
if (k2 === undefined) k2 = k;
var desc = Object.getOwnPropertyDescriptor(m, k);
if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
desc = { enumerable: true, get: function() { return m[k]; } };
}
Object.defineProperty(o, k2, desc);
}) : (function(o, m, k, k2) {
if (k2 === undefined) k2 = k;
o[k2] = m[k];
}));
var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) {
Object.defineProperty(o, "default", { enumerable: true, value: v });
}) : function(o, v) {
o["default"] = v;
});
var __importStar = (this && this.__importStar) || function (mod) {
if (mod && mod.__esModule) return mod;
var result = {};
if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
__setModuleDefault(result, mod);
return result;
};
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
return new (P || (P = Promise))(function (resolve, reject) {
function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
step((generator = generator.apply(thisArg, _arguments || [])).next());
});
};
var __importDefault = (this && this.__importDefault) || function (mod) {
return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.pdf = void 0;
require("./polyfill"); // do this before pdfjs
const node_path_1 = __importDefault(require("node:path"));
// 🛑 inspite of esModuleInterop being on, you still need to use `import *`, and there are no typedefs
const _pdfjs = __importStar(require("pdfjs-dist/legacy/build/pdf"));
const canvasFactory_1 = require("./canvasFactory");
const parseInput_1 = require("./parseInput");
const pdfjs = _pdfjs;
const pdfjsPath = node_path_1.default.dirname(require.resolve("pdfjs-dist/package.json"));
/** required since k-yle/pdf-to-img#58, the objects from pdfjs are weirdly structured */
const sanitize = (x) => {
const object = JSON.parse(JSON.stringify(x));
// remove UTF16 BOM and weird 0x0 character introduced in k-yle/pdf-to-img#138 and k-yle/pdf-to-img#184
for (const key in object) {
if (typeof object[key] === "string") {
// eslint-disable-next-line no-control-regex -- this is deliberate
object[key] = object[key].replaceAll(/(^þÿ|\u0000)/g, "");
}
}
return object;
};
/**
* Converts a PDF to a series of images. This returns a `Symbol.asyncIterator`
*
* @param input Either (a) the path to a pdf file, or (b) a data url, or (c) a buffer, or (d) a ReadableStream.
*
*/
function pdf(input, options = {}) {
return __awaiter(this, void 0, void 0, function* () {
if (options.scale && (options.maxWidth || options.maxHeight)) {
console.warn("pdf-to-img: The 'scale' option is not recommended when 'maxWidth' or 'maxHeight' are specified. Scaling is determined by the max values.");
}
const data = yield (0, parseInput_1.parseInput)(input);
const pdfDocument = yield pdfjs.getDocument(Object.assign(Object.assign({ password: options.password, standardFontDataUrl: node_path_1.default.join(pdfjsPath, `standard_fonts${node_path_1.default.sep}`), cMapUrl: node_path_1.default.join(pdfjsPath, `cmaps${node_path_1.default.sep}`), cMapPacked: true, isEvalSupported: false }, options.docInitParams), { data })).promise;
const metadata = yield pdfDocument.getMetadata();
return {
length: pdfDocument.numPages,
metadata: sanitize(metadata.info),
[Symbol.asyncIterator]() {
return {
pg: 0,
next() {
var _a, _b, _c;
return __awaiter(this, void 0, void 0, function* () {
if (this.pg < pdfDocument.numPages) {
this.pg += 1;
const page = yield pdfDocument.getPage(this.pg);
let viewport = page.getViewport({ scale: (_a = options.scale) !== null && _a !== void 0 ? _a : 1 });
let targetWidth = (_b = options.maxWidth) !== null && _b !== void 0 ? _b : viewport.width;
let targetHeight = (_c = options.maxHeight) !== null && _c !== void 0 ? _c : viewport.height;
if (options.maintainAspectRatio) {
let scaleX = targetWidth / viewport.width;
let scaleY = targetHeight / viewport.height;
let scale = Math.min(scaleX, scaleY);
viewport = page.getViewport({ scale: scale });
}
else {
// Maintain the scale, but set the canvas dimensions to be what the target is to prevent ratio issues
let scaleX = targetWidth / viewport.width;
let scaleY = targetHeight / viewport.height;
viewport = page.getViewport({ scale: Math.min(scaleX, scaleY) });
}
const canvasFactory = new canvasFactory_1.NodeCanvasFactory();
const { canvas, context } = canvasFactory.create(Math.round(viewport.width), Math.round(viewport.height));
yield page.render({
canvasContext: context,
viewport,
canvasFactory,
}).promise;
return { done: false, value: canvas.toBuffer() };
}
return { done: true, value: undefined };
});
},
};
},
};
});
}
exports.pdf = pdf;