Head-up display apparatus and method of processing video data

1 . A head-up display apparatus mounted on a transportation, the head-up display apparatus comprising:

an information acquiring portion configured to acquire information on the transportation;

a video display configured to display a video and to output video light of the displayed video;

a video-light projector configured to project the video light output from the video display to a display region, thereby causing the projected video light to be visually recognized as a virtual image; and

a controller configured to prepare video data based on the information on the transportation acquired by the information acquiring portion, and to cause the video display to display a video based on the prepared video data,

wherein the controller performs control to reduce a processing load required for preparing the video data such that the video data is completely prepared within a predetermined processing cycle, and

wherein the controller monitors a preparation time required for preparing the video data, and starts the control to reduce the processing load if the preparation time meets a predetermined condition.

2 . The head-up display apparatus according to claim 1 ,

wherein the controller starts the control to reduce the processing load if the preparation time is longer than the processing cycle.

3 . The head-up display apparatus according to claim 1 ,

wherein, with reference to a first threshold time shorter than the processing cycle, the controller starts the control to reduce the processing load if the preparation time is longer than the first threshold time in a plural number of times in a row.

4 . The head-up display apparatus according to claim 1 ,

wherein, after the start of the control to reduce the processing load, the controller increases stepwise a reduction amount of the processing load for each processing cycle within a suppression transit period.

5 . The head-up display apparatus according to claim 4 ,

wherein, after the suppression transit period, the controller decreases stepwise the reduction amount of the processing load for each processing cycle within a restoration transit period.

6 . The head-up display apparatus according to claim 5 ,

wherein, after the suppression transit period, and then, after a suppression period in which the video data is prepared at the reduced processing load, the controller performs the control within the restoration transit period.

7 . The head-up display apparatus according to claim 6 ,

Wherein, in the suppression period, with reference to a second threshold time shorter than the processing cycle and a threshold duration that is a period multiple times of the processing cycle or longer, the controller starts the control in the restoration transit period if the preparation time shorter than the second threshold time is continued for the threshold duration or longer.

8 . The head-up display apparatus according to claim 4 ,

wherein, in the suppression transit period, the controller generates the video data in order to notify a user of the suppression transit period.

9 . The head-up display apparatus according to claim 1 ,

wherein the controller reduces the processing load by reducing an amount of the video data to be prepared.

10 . A head-up display apparatus mounted on a transportation, the head-up display apparatus comprising:

an information acquiring portion configured to acquire information on the transportation;

a video display configured to display a video and to output video light of the displayed video; and

a video-light projector configured to project the video light output from the video display to a display region, thereby causing the projected video light to be visually recognized as a virtual image,

wherein video data is prepared based on the information on the transportation acquired by the information acquiring portion, and a part of the video data to be prepared is changed if at least one condition for preparing the video data does not meet a predetermined condition in a predetermined processing cycle, and

wherein a control to change the part of the video data to be prepared is started if a preparation time, as one of the at least one condition for preparing the video data, does not meet the predetermined condition.

11 . A head-up display apparatus mounted on a transportation, the head-up display apparatus comprising:

an information acquiring portion configured to acquire information on the transportation;

a video display configured to display a video and to output video light of the displayed video;

a video-light projector configured to project the video light output from the video display to a display region, thereby causing the projected video light to be visually recognized as a virtual image; and

a controller configured to determine display contents based on the information on the transportation acquired by the information acquiring portion, to prepare video data based on the determined display contents, and to cause the video display to display a video based on the prepared video data,

wherein, if a preparation time required for preparing the video data of tentatively-determined display contents before determining the display contents is longer than a predetermined processing cycle, the controller changes the tentatively-determined display contents, and

wherein, before determining the display contents, the controller predicts the preparation time required for preparing the video data based on the tentatively-determined display contents, predicted based on predicted time information for defining a relationship between the display contents and a predicted time required for preparing the video data, and changes the tentatively-determined display contents such that the preparation time is shorter than the processing cycle if the preparation time is longer than the processing cycle.

12 . The head-up display apparatus according to claim 11 ,

wherein items in changing the tentatively-determined display contents include the number of videos or a display format of each video, and

items in changing the display format of each video include at least one of a size, a display position, and a design type.

13 . The head-up display apparatus according to claim 12 ,

wherein the controller previously stores priority information for defining a priority of each of the items, and changes the tentatively-determined display contents while increasing the items to be changed based on the priority information until the preparation time is shorter than the processing cycle.

14 . The head-up display apparatus according to claim 13 ,

wherein the items in changing the tentatively-determined display contents include the number of videos and the display format of each video, and

the number of videos in the priority information is set to have a lower priority than a priority of the display format of each video.

15 . The head-up display apparatus according to claim 12 ,

wherein the predicted time information includes a basic time and a coefficient of each of the items included in the display format of each video, and

the controller predicts the preparation time by multiplying the basic time by the coefficient.

16 . The head-up display apparatus according to claim 11 ,

wherein the information acquiring portion acquires a distance between the transportation mounting the head-up display apparatus and an object present ahead of the transportation, and

if an alert video is superimposed on the object, the controller determines a color or a shape of the alert video, depending on the distance to the object.

17 . The head-up display apparatus according to claim 16 ,

wherein the controller determines the display contents such that the preparation time is shorter than the processing cycle, and then, updates the color or the shape of the alert video without predicting the preparation time again if the alert video is included in the determined display contents.