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You can also use the top-left pixel in the source image as the transparent color
<div style="background-color:Red;width:130px;height:130px;padding-left:30px;padding-top:30px">
	<p>
		@Html.DynamicImageTag(b => b.ImageFormat(DynamicImageFormat.Png).FillBackgroundColor(Colors.Transparent).WithLayer(
			LayerBuilder.Image.SourceFile("~/Assets/Images/bmw.jpg")
				.WithFilter(FilterBuilder.ColorKey.Color(Colors.White).ColorTolerance(5))
		))
	</p>
</div>