Setting pixel dimensions for an ImageRGBA glyph

How would one go about displaying an ImageRGBA glyph with exact pixel dimensions in the browser? For example, if I had an 800 x 600 image that I converted to a 2-d array (600 rows and 800 columns) of color values, I would like for the ImageRGBA glyph to render with the dimensions 800 x 600 in the browser. This is different than setting the size of the figure, which includes axes, etc.