Attach (recommended) or Link to PDF file here:
https://s3.eu-west-1.amazonaws.com/scai-dev.website.com/tmp/8ab8b56a-fa91-11eb-8d74-0242ac110004.pdf

Hi,
Please see an incorrect canvas rendering for the following document - page 9 specifically. It reproduces on https://mozilla.github.io/pdf.js/web/viewer.html (tried with Chrome). Other pages in this document look pretty much the same but the problem is on page 9 only.

Original screenshot:
![image](https://user-images.githubusercontent.com/23075641/129066656-7bb2fb56-2b88-4f40-8e67-b95bdeb9e521.png)


PDF JS:

![image](https://user-images.githubusercontent.com/23075641/129066734-56503a5c-413c-49c1-9e1c-470da3a642ed.png)

transferMapGreen = transferMaps[0];
        transferMapBlue = transferMaps[0];
        transferMapGray = transferMaps[0];
        break;
      case 4:
        transferMapRed = transferMaps[0];
        transferMapGreen = transferMaps[1];
        transferMapBlue = transferMaps[2];
        transferMapGray = transferMaps[3];
        break;
    }
  }
  
  
  if (imgData.kind === ImageKind.GRAYSCALE_1BPP) {
    
    const srcLength = src.byteLength;
    const dest32 = new Uint32Array(dest.buffer, 0, dest.byteLength >> 2);
    const dest32DataLength = dest32.length;
    const fullSrcDiff = (width + 7) >> 3;
    let white = 0xffffffff;
    let black = IsLittleEndianCached.value ? 0xff000000 : 0x000000ff;
    if (transferMapGray) {
      if (transferMapGray[0] === 0xff && transferMapGray[0xff] === 0) {
        [white, black] = [black, white];
      }
    }
    for (i = 0; i < totalChunks; i++) {
      thisChunkHeight = i < fullChunks ? FULL_CHUNK_HEIGHT : partialChunkHeight;
      destPos = 0;