This is solved with embed tag in html,  as in "MIME encoding of a PDF file in an HTML page".
This resulted in error 
"Error: unsafe value used in a resource URL context (see
  g.co/ng/security#xss) at
  DomSanitizerImpl.push../node_modules/@angular/platform-browser/fesm5/platform-browser.js.DomSanitizerImpl.sanitize
  (platform-browser.js:1812)"
This was later solved with Unsafe value used in a resource URL context with Angular 2 using DomSanitizer, answered by @helzgate as method 1. 
Overall code:
in HTML:
<embed [src]='sanitizer.bypassSecurityTrustResourceUrl(imgURL)' height="200" *ngIf="imgURL">
In typescript,add the following in component:
import { DomSanitizer } from '@angular/platform-browser';
and
  constructor(public sanitizer: DomSanitizer) { }