transpValue not working properly for rgb geotiff?

[teoxonline]

Hi, your code is not working as expected
for RGB geotiff with 3 active bands when you set transpValue you should check for all the three r,g,b values matches the trasnpValue, not only for the alphaBand specified, your case is useful for single layer geotiff but for three bands rgb, to avoid holes in the final composite rapresentation, the transpValue:0 should match the rgb(0,0,0)

  const a = this.options.transpValue ? data[this.options.alphaBand].map(v => {
    return v == this.options.transpValue ? 0 : 255;
  }) : data[this.options.alphaBand];