Graphics Generation Device Comprising Means For Monitoring Its Operation

• US 20080211814A1
• Filed: 04/20/2006
• Published: 09/04/2008
• Est. Priority Date: 04/26/2005
• Status: Active Grant

• Current Assignee: Thales SA
• Original Assignee: Thales SA
• Inventors: Filliatre, Eric, Capircio, Patrice
• Granted Patent: US 8,009,163 B2
• Time in Patent Office: Days
• US Class Current: 345/441
• CPC Class Codes: G06T 1/60 Memory management
• CPC Class Codes: G06T 11/00 2D [Two Dimensional] image generation

Abstract

The field of the invention relates to the operational safety, security and reliability of Man/Machine Interface systems displaying information in the form of graphics or symbology. The monitoring principles according to the prior art are all based on monitoring graphical information coming from the display system and the verification that this information really corresponds to the input parameters. The heart of the invention is to monitor the correct operation of the graphics generation functions, independently of the data that they process. More precisely, the invention relates to a device for the graphical generation of symbologies intended for a display screen, the device having functions for the generation of symbology elements and means for monitoring its correct operation. The monitoring correct operation allows the use of certain of the functions for the generation of symbology elements to be prohibited and second allows micro-images dedicated to the monitoring of the functions to be generated and controlled.

Claims

1. The device for the graphical generation of symbologies intended for a display screen, the said device comprising functions for the generation of symbology elements and means for monitoring its correct operation, comprising:

first means allowing the use of certain of the said functions for the generation of symbology elements to be prohibited; and

second means allowing micro-images dedicated to the monitoring of the said functions to be generated and controlled.

2. The graphics generation device according to claim 1, wherein the prohibited functions are functions that are capable of generating recurrent symbol elements.

3. The graphics generation device according to claim 1, wherein the prohibited functions are macro-functions comprising a plurality of elementary functions for generating symbology elements.

4. The graphics generation device according to claim 1, comprising a memory comprising a first region intended for the storage of the symbology and a second region, the micro-images being generated in this second region.

5. The graphics generation device according to claim 1, comprising a memory comprising a first region intended for the storage of the symbology, the second monitoring means allowing micro-images to be generated in this first region during a short period of time compared with the refresh time of the symbology on the display screen.

6. The graphics generation device according to claim 1, comprising third monitoring means allowing certain state variables internal to the graphics generation device to be monitored.

7. The graphics generation device according to claim 6, wherein the said third means comprise means for computing the said internal state variables independent of those of the graphics generation device.

8. A method for monitoring the correct operation of a graphics generation device according to claim 5, comprising the following steps:

tracing of the micro-image within the first region;

calculating a mathematical signature for the micro-image;

comparing the calculated signature with an expected signature;

erasing of the micro-image; and

tracing of the operational image.

9. The graphics generation device according to claim 1, the said device being Graphics Processing Unit (GPU).

10. The graphics generation device according to claim 1, wherein the graphics generation functions and the monitoring means are integrated with a reception structure comprising a Central Processing Unit (CPU).

11. The graphics generation device according to claim 1, wherein the functions for generation of symbology elements are written in an OpenGL language, acronym for Open Graphics Langage.

12. The device for the graphical generation of symbologies intended for a display screen according to claim 1, wherein the display screen is of the LCD type, acronym for Liquid Crystal Display.

13. The device for the graphical generation of symbologies intended for a display screen according to claim 1, wherein the symbology is of the aeronautics type and represents symbols useful at least for the piloting and navigation of aircraft.