Android : How to output an image file to external display using HDMI connector and matintain the image resoulution

I'm trying to write an app that can output an image file to external display by connecting HDMI. Now I use only an ImageView in the page to place the image and set fill_parent for both height and width. My device's resolution is 1024*736, and I connect my device to a 50" TV which is 1920*1080 to display the image. And the result is horrible. The image is 1920*1080 and its definitely being downscaled.

Does anyone know how to maintain the resolution of the image while displaying to external device??

Thank you!!