Image synthesizing device

Abstract

An image synthesizing device includes a graphics data expanding unit 2 for securing a rectangular area 4a whose alpha value is “0” in a region of a non-display memory 4, the region corresponding to a display area in which moving image data is to be displayed, and for expanding motionless graphics data onto a region of the non-display memory 4, the region corresponding to a display area in which the motionless graphics data is to be displayed, and a moving image data expanding unit 3 for expanding the moving image data onto a non-display memory 5. The image synthesizing device then synthesizes the graphics data which are expanded onto the non-display memory 4 and the graphics data which are expanded onto the non-display memory 5.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing an image synthesizing device in accordance with embodiment 1 of the present invention; and

FIG. 2 is a diagram showing expanding processing carried out by a graphics data expanding unit 2 of the image synthesizing device in accordance with embodiment 1 of the present invention.

Claims

1. An image synthesizing device comprising: a graphics data expanding means for, when input graphics data to be synthesized is moving image data, securing a rectangular area whose transmittance information indicates perfect transparence in a region of a first non-display memory, the region corresponding to a display area in which said moving image data is to be displayed, and for, when the input graphics data to be synthesized is motionless graphics data, expanding said input graphics data onto a region of said first non-display memory, the region corresponding to a display area in which said motionless graphics data is to be displayed;a moving image data expanding means for, when the input graphics data to be synthesized is moving image data, expanding said moving image data onto a second non-display memory; andan image synthesizing means for synthesizing the graphics data which are expanded onto said first non-display memory by said graphics data expanding means, and the graphics data which are expanded onto said second non-display memory by said moving image data expanding means.

2. The image synthesizing device according to claim 1, wherein when transferring moving image data which is expanded onto said second non-display memory to a region of an entire non-display memory, the region corresponding to the display area in which the moving image data is to be displayed, said image synthesizing means transfers the graphics data which are expanded onto said first non-display memory in which the rectangular area whose transmittance information indicates perfect transparence is secured in the region corresponding to the display area in which said moving data is to be displayed to said entire non-display memory.

3. The image synthesizing device according to claim 1, wherein every when said moving image data is updated, said moving image data expanding means expands said moving image data onto said second non-display memory.

4. The image synthesizing device according to claim 1, wherein when synthesizing the graphics data which are expanded onto said first non-display memory and the graphics data which are expanded onto said second non-display memory, said image synthesizing means adjusts a depth value of said moving image data which are expanded onto said second non-display memory.