Monitoring apparatus

1. A monitoring apparatus comprising:

plural imaging units;

a viewpoint conversion unit making viewpoint conversion of each imaged picture of the plural imaging units into an overhead picture with the same depression angle, respectively; and

a picture composite unit joining each overhead picture obtained from the viewpoint conversion unit to superimpose the same scene portion of each overhead picture, and generating a wide overhead picture, wherein the picture composite unit adopts a picture of a superimposed portion in the overhead picture with the highest picture quality of the superimposed portion among each overhead picture related to the superimposed portion as a picture of the superimposed portion of the wide overhead picture.

2. A monitoring apparatus according to claim 1 , wherein an overhead picture in which an amount of depression angle change before and after the viewpoint conversion is smallest is selected as the overhead picture with the highest picture quality of the superimposed portion.

3. A monitoring apparatus according to claim 1 , wherein the overhead picture in which resolution of the superimposed portion is highest is selected as the overhead picture with the highest picture quality of the superimposed portion.

4. A monitoring apparatus according to claim 1 , wherein the overhead picture in which the same scene portion shown in a picture portion before the viewpoint conversion of the superimposed portion is largest shown is selected as the overhead picture with the highest picture quality of the superimposed portion.

5. A monitoring apparatus according to claim 1 , wherein the overhead picture in which distortion of a picture of the superimposed portion is smallest is selected as the overhead picture with the highest picture quality of the superimposed portion.

6. A monitoring apparatus according to claim 1 , wherein the plural imaging units are set in a vehicle, and

wherein the plural imaging units image the periphery of the vehicle.