PDF.js displays blurry plots in PDF documents, e.g.

http://arxiv.org/pdf/1202.5344v1.pdf

When viewed in Chrome or Adobe Acrobat all the plots show sharp-edged squares. When viewed in Preview or PDF.js, all the squares show as blurry pixelated blobs.

);
    const tmpCtx = tmpCanvas.context;
    const data = tmpCtx.createImageData(width, height);
    if (backgroundColor) {
      const bytes = data.data;
      for (let i = 0, ii = bytes.length; i < ii; i += 4) {
        bytes[i] = backgroundColor[0];
        bytes[i + 1] = backgroundColor[1];
        bytes[i + 2] = backgroundColor[2];
        bytes[i + 3] = 255;
      }
    }
    for (const figure of this._figures) {
      drawFigure(data, figure, context);
    }
    tmpCtx.putImageData(data, BORDER_SIZE, BORDER_SIZE);
    const canvas = tmpCanvas.canvas;
    return {
      canvas,
      offsetX: offsetX - BORDER_SIZE * scaleX,
      offsetY: offsetY - BORDER_SIZE * scaleY,
      scaleX,
      scaleY,
    };
  }
  getPattern(ctx, owner, shadingFill = false, patternTransform = null) {
    applyBoundingBox(ctx, this._bbox);
    let scale;
    if (shadingFill) {
      scale = Util.singularValueDecompose2dScale(ctx.mozCurrentTransform);