A method of controlling a head-up display, HUD,, the method comprising: performing eye tracking of an eye of a user in a captured image; characterized by: identifying an eye tracking status based on a result of the eye tracking identifying a rendering mode for an HUD image to be one of a two-dimensional, 2D, rendering mode and a three-dimensional, 3D, rendering mode based on the eye tracking status; and rendering the HUD image in the identified rendering mode, wherein the identifying the eye tracking status comprises classifying the eye tracking status as one of a stable status and an unstable status based on whether eye coordinates are present in the result of the eye tracking and based on a speed of position change with respect to the eye coordinates, wherein the identifying the rendering mode comprises: identifying the rendering mode to be the 3D rendering mode based on the eye tracking status being classified as the stable status; and identifying the rendering mode to be the 2D rendering mode based on the eye tracking status being classified as the unstable status, wherein the eye tracking status is classified as the stable status based on the eye coordinates being included in the result of the eye tracking and a speed of position change with respect to the eye coordinates is less than a threshold, and wherein the eye tracking status is classified as the unstable status based on the eye coordinates being included in the result of the eye tracking and the speed of position change with respect to the eye coordinates is greater than the threshold. performing eye tracking of an eye of a user in a captured image; characterized by: identifying an eye tracking status based on a result of the eye tracking identifying a rendering mode for an HUD image to be one of a two-dimensional, 2D, rendering mode and a three-dimensional, 3D, rendering mode based on the eye tracking status; and rendering the HUD image in the identified rendering mode, wherein the identifying the eye tracking status comprises classifying the eye tracking status as one of a stable status and an unstable status based on whether eye coordinates are present in the result of the eye tracking and based on a speed of position change with respect to the eye coordinates, wherein the identifying the rendering mode comprises: identifying the rendering mode to be the 3D rendering mode based on the eye tracking status being classified as the stable status; and identifying the rendering mode to be the 2D rendering mode based on the eye tracking status being classified as the unstable status, wherein the eye tracking status is classified as the stable status based on the eye coordinates being included in the result of the eye tracking and a speed of position change with respect to the eye coordinates is less than a threshold, and wherein the eye tracking status is classified as the unstable status based on the eye coordinates being included in the result of the eye tracking and the speed of position change with respect to the eye coordinates is greater than the threshold. identifying an eye tracking status based on a result of the eye tracking identifying a rendering mode for an HUD image to be one of a two-dimensional, 2D, rendering mode and a three-dimensional, 3D, rendering mode based on the eye tracking status; and rendering the HUD image in the identified rendering mode, wherein the identifying the eye tracking status comprises classifying the eye tracking status as one of a stable status and an unstable status based on whether eye coordinates are present in the result of the eye tracking and based on a speed of position change with respect to the eye coordinates, wherein the identifying the rendering mode comprises: identifying the rendering mode to be the 3D rendering mode based on the eye tracking status being classified as the stable status; and identifying the rendering mode to be the 2D rendering mode based on the eye tracking status being classified as the unstable status, identifying the rendering mode to be the 3D rendering mode based on the eye tracking status being classified as the stable status; and identifying the rendering mode to be the 2D rendering mode based on the eye tracking status being classified as the unstable status, wherein the eye tracking status is classified as the stable status based on the eye coordinates being included in the result of the eye tracking and a speed of position change with respect to the eye coordinates is less than a threshold, and wherein the eye tracking status is classified as the unstable status based on the eye coordinates being included in the result of the eye tracking and the speed of position change with respect to the eye coordinates is greater than the threshold.