Method and system for synchronizing colorimetric rendering of a juxtaposition of display surfaces

1. A method for adjusting a colorimetric rendering of a display surface, said display surface including at least one pair of adjacent display screens, each controlled by a video processing system through which a corresponding video stream passes for each pair of adjacent display screens, the method comprising:

receiving image data of images in the video stream displayed on a separation area located between two screens of each pair of adjacent display screens, wherein the image data comprises colorimetric measurements for each screen in each pair of adjacent display screens, and wherein the colorimetric measurements are taken from measurement areas distributed symmetrically on each side of the separation area;

periodically sampling the image data;

analyzing the image data sampled in each period to determine a difference in colorimetric rendering between the two screens in the pair of adjacent display screens; and

applying a correction law, based on the difference in colorimetric rendering, to the images in the video stream of one of two video processing systems controlling the pair of adjacent display screens.

2. The method according to claim 1 , wherein the image data are obtained using a video camera placed overlapping the separation area.

3. The method according to claim 1 , wherein the analysis of sampled image data comprises:

determining average color components in each measurement area; and

comparing each average color component in one of the two measurement areas with a corresponding average color component in the other measurement area to determine differences in color components which form the difference in colorimetric rendering.

4. The method according to claim 3 , wherein average color components in each measurement area are determined from color components on each pixel in the measurement area.

5. The method according to claim 1 , wherein image data are sampled at time intervals of a few minutes to a few tens of minutes.

6. The method according to claim 1 , wherein the correction law applied by the correction device to the difference in colorimetric rendering is a matrix type law.

7. The method according to claim 1 , wherein the correction law applied by the correction device to the difference in colorimetric rendering is an iterative type law with a convergence criterion.

8. The method according to claim 1 , comprising:

comparing the difference in colorimetric rendering with a predefined threshold; and

applying no correction processing to the video stream of either of the two video processing systems controlling the pair of adjacent display screens if the difference in the colorimetric rendering is greater than the threshold.

9. The method according to claim 8 , further comprising:

sending an alert signal indicating that a manual adjustment of the video processing systems is necessary to make the colorimetric rendering of the display surface uniform if the difference in colorimetric rendering is greater than the threshold for several consecutive periods.

10. The method according to claim 1 , further comprising:

storing a history of colorimetric differences determined for each pair of adjacent display screens; and

performing an analysis of the history to set up a colorimetric drifts law for each display screen.

11. A system for making a colorimetric rendering of a display surface uniform, said display surface including at least one pair of adjacent display screens, each controlled by a video processing system through which a corresponding video stream passes, the system comprising:

a correction system correcting the colorimetric rendering of one display screen of said pair of adjacent display screens, the correction system including:

a sensor for supplying image data of images displayed on the pair of adjacent display screens;

a calculation device connected to the sensor and configured to periodically sample image data from among the image data supplied by the sensor and to a first difference in colorimetric rendering between two screen areas respectively situated in the pair of adjacent display screens and

a correction device connected to the calculation device and configured to determine, by applying a correction law based on the first difference in colorimetric rendering to a corrected video stream of one of two video processing systems controlling the pair of adjacent display screens and to apply said process to the video stream to make the colorimetric rendering of the display surface uniform, wherein the correction law comprises:

while the first difference is greater than a predetermined threshold:

applying the first difference in colorimetric rendering to each pixel of images in the corrected video stream,

determining a second difference in colorimetric rendering between the two screen areas after applying the first difference in colorimetric rendering,

comparing the second difference to the first difference, and

responsive to the second difference being greater than the first difference, applying a matrix correction method to the corrected video stream.

12. The system according to claim 11 , wherein the sensor is a video camera placed overlapping a separation area between the pair of adjacent display screens.