"Warning: fetchStandardFontData: failed to fetch file "LiberationSans-Regular.ttf" with "UnknownErrorException"

[sayo96]

I'm getting this weird warning whenever I load a pdf. How do I fix this?

Second Question:
I'm using pdfjs-dist on node js environment and I want to modify and remove the field values from all the fields on a page and save the resulting pdf. Please let me know how can I achieve that 🙏

[kallebysantos]

I'm using Deno, and got a similar error:

code:

import { createCanvas } from "jsr:@gfx/[email protected]";
import { getDocument } from "npm:[email protected]";
import { Err, Ok, Result } from "@src/lib/result.ts";

export async function loadImageDocument(
  storagePath: string,
) {
  console.info("Loading file", storagePath);

  const fileBlob = await Result.wrapAsync<Blob, Error>(async () => {
    const response = await fetch(new URL(storagePath));
    return await response.blob();
  });

  if (fileBlob.isErr()) {
    return Err(fileBlob.error);
  }

  const file = await fileBlob.value.arrayBuffer();

  getDocument(file).promise
  .then(async (pdf) => {

    const page = await pdf.getPage(1);
    const viewport = page.getViewport({ scale: 1.0 });

    const canvas = createCanvas(
      Math.floor(viewport.width),
      Math.floor(viewport.height),
    );

    await  page.render({
      canvasContext: canvas.getContext("2d"),
      viewport,
    }).promise;

    canvas.save("image.png");
  });

  return Ok.EMPTY;
}

Loading file file:/home/kalleby/projects/my-project/examples/file.pdf
Warning: fetchStandardFontData: failed to fetch file "FoxitSerif.pfb" with "UnknownErrorException: The standard font "baseUrl" parameter must be specified, ensure that the "standardFontDataUrl" API parameter is provided.".
Warning: fetchStandardFontData: failed to fetch file "FoxitSerif.pfb" with "UnknownErrorException: The standard font "baseUrl" parameter must be specified, ensure that the "standardFontDataUrl" API parameter is provided.".
Warning: fetchStandardFontData: failed to fetch file "FoxitSerifBold.pfb" with "UnknownErrorException: The standard font "baseUrl" parameter must be specified, ensure that the "standardFontDataUrl" API parameter is provided.".
Warning: fetchStandardFontData: failed to fetch file "FoxitSerifItalic.pfb" with "UnknownErrorException: The standard font "baseUrl" parameter must be specified, ensure that the "standardFontDataUrl" API parameter is provided.".

The process simple just exits after this "warnings"

NOTE: The text extraction works fine and I'm already using it within langchain PDFLoader, but render as image not. I need to render it in order to use tesseract.

I already tried to specify the standardFontDataUrl with the following attempts:

  getDocument({
    data: file,
    standardFontDataUrl: 
     "https://github.com/mozilla/pdf.js/raw/master/external/standard_fonts/",
    // "https://cdn.jsdelivr.net/npm/[email protected]/standard_fonts/"
    // Donwload the files to a local folder and use relative location to it
  })

But always got Unable to load font data at: <location>.
Also tried to specify useWorkerFetch: true and/or useSystemFonts: true.
But in theses cases the Deno process just exit without any error message.

[dualdetail]

For me, I was able to get it working in a docker container by copying the standard_fonts folder in and using the folder path as the standardFontDataUrl. Eg COPY ./standard_fonts /etc/standard_fonts

And then getDocument({data:file, standardFontDataUrl: "/etc/standard_fonts/"})