Abstract: A method for inspecting a tire's surface includes: capturing a reference image of a reference tire's surface relief elements and transmitting data of the reference image to a processor; parameterizing main characteristics of the reference image via interaction of an operator with the processor; producing a reference map of the surface relief elements by dividing the reference image into a plurality of reference zones of interest; assigning a specific registration and checking algorithm to each of the reference zones of interest; capturing an inspection image of a tire under inspection; and, after completion of pre-processing of the inspection image, automatically: superimposing the reference map on the inspection image, and, for each of a plurality of zones of interest of the inspection image, running the specific registration and checking algorithm for a corresponding one of the reference zones of interest, to determine a conformity of the tire under inspection.

Abstract: A method for inspecting a tire's surface includes: capturing a reference image of a reference tire's surface relief elements and transmitting data of the reference image to a processor; parameterizing main characteristics of the reference image via interaction of an operator with the processor; producing a reference map of the surface relief elements by dividing the reference image into a plurality of reference zones of interest; assigning a specific registration and checking algorithm to each of the reference zones of interest; capturing an inspection image of a tire under inspection; and, after completion of pre-processing of the inspection image, automatically: superimposing the reference map on the inspection image, and, for each of a plurality of zones of interest of the inspection image, running the specific registration and checking algorithm for a corresponding one of the reference zones of interest, to determine a conformity of the tire under inspection.

Abstract: To analyze a tire surface, a 3D elevational image is captured, which is formed of pixels representing points on the surface. Each point is assigned a grey-level value proportional to its elevation relative to a surface level. Based on the elevations in the elevational image, an orientational image is formed showing elevation gradients of the surface. In the orientational image, which is formed of pixels representing points on the surface, each point is assigned a grey-level value proportional to an angle formed with a direction given by a projection in an image plane of a non-zero norm vector substantially corresponding, at this point, to a gradient vector tangent to the surface and oriented in a direction of greatest slope. A filtered image is determined by transforming the orientational image using a filter to select areas that include structures similar to those in a reference orientational image of a blow hole.

Abstract: In this method for referencing striations present in digital representations (10) of tires, automated means execute the following steps in order to reference types of striation: determining at least one representation comprising a type of striation (1, 2) to be referenced, identifying at least one segment of pixels or voxels of the representation (10), and recording at least one value relating to differences between grey levels or colour levels of pixels or voxels of the segment.

Abstract: To analyze a tyre surface, a 3D elevational image is captured, which is formed of pixels representing points on the surface. Each point is assigned a grey-level value proportional to its elevation relative to a surface level. Based on the elevations in the elevational image, an orientational image is formed showing elevation gradients of the surface. In the orientational image, which is formed of pixels representing points on the surface, each point is assigned a grey-level value proportional to an angle formed with a direction given by a projection in an image plane of a non-zero norm vector substantially corresponding, at this point, to a gradient vector tangent to the surface and oriented in a direction of greatest slope. A filtered image is determined by transforming the orientational image using a filter to select areas that include structures similar to those in a reference orientational image of a blow hole.

Abstract: A method for inspecting a portion of a tire surface involves comparison with an image of a three-dimensional (“3D”) reference surface. The method includes: extracting contours of graphic elements of an image of a 3D profile of a surface to be inspected; transforming the reference surface by establishing a correspondence between the contours of the graphic elements of the surface to be inspected and contours of identical graphic elements of the reference surface using a series of transformations; associating a B-spline surface, which includes control points, with the graphic elements of the transformed reference surface; and deforming the contours of the graphic elements of the reference surface by modifying positions of the control points of the B- spline surface so as to minimize distances between the contours of the graphic elements of the reference surface and the contours of the graphic elements of the surface to be inspected corresponding thereto.

Abstract: A method for inspecting a portion of a tyre surface involves comparison with an image of a three-dimensional (“3D”) reference surface. The method includes: extracting contours of graphic elements of an image of a 3D profile of a surface to be inspected; transforming the reference surface by establishing a correspondence between the contours of the graphic elements of the surface to be inspected and contours of identical graphic elements of the reference surface using a series of transformations; associating a B-spline surface, which includes control points, with the graphic elements of the transformed reference surface; and deforming the contours of the graphic elements of the reference surface by modifying positions of the control points of the B-spline surface so as to minimize distances between the contours of the graphic elements of the reference surface and the contours of the graphic elements of the surface to be inspected corresponding thereto.

Abstract: A method for inspecting a tyre surface involves comparison with an image of a three-dimensional (“3D”) reference surface. The method includes: extracting contours of graphic elements of an image of a 3D profile of a tyre surface to be inspected; locating characteristic points on the image of the tyre surface, and pairing the characteristic points with corresponding reference characteristic points on the image of the reference surface; associating a first reset B-spline surface with the reference surface by associating the reference characteristic points of the image of the reference surface with control points of the first reset B-spline surface; and deforming the reference surface by moving the control points of the first reset B-spline surface so as to superpose the control points on the characteristic points of the tyre surface, in accordance with the reference characteristic points of the reference surface paired with the characteristic points of the tyre surface.

Abstract: Method for inspecting a zone of the surface of a tire, said surface comprising markings in relief, wherein the three-dimensional profile of the surface to be inspected is determined, characteristic points on the surface to be inspected are located and these points are matched with the corresponding points originating from the three-dimensional data of a reference surface, so as to create a set of pairs of matched points, in an iterative manner, a first affine transformation function is sought, applied to the characteristic points of the reference surface, so that the value representing the sum of the distances between each of the characteristic points of the reference surface, which points are transformed with the aid of said first transformation function, and the points of the surface to be inspected that are matched with them, is minimal, and said first transformation function is applied to all of the points of the reference surface in order to obtain a transformed reference surface.

Abstract: Method for inspecting a zone of the surface of a tire, said surface comprising markings in relief, wherein the three-dimensional profile of the surface to be inspected is determined, characteristic points on the surface to be inspected are located and these points are matched with the corresponding points originating from the three-dimensional data of a reference surface, so as to create a set of pairs of matched points, in an iterative manner, a first affine transformation function is sought, applied to the characteristic points of the reference surface, so that the value representing the sum of the distances between each of the characteristic points of the reference surface, which points are transformed with the aid of said first transformation function, and the points of the surface to be inspected that are matched with them, is minimal, and said first transformation function is applied to all of the points of the reference surface in order to obtain a transformed reference surface.