GB2530997A

GB2530997A - Method And Device For Processing An Image

Info

Publication number: GB2530997A
Application number: GB1417613.5A
Authority: GB
Inventors: Thoumy Francois; Caillerie Alain; Lorgeoux Michaël
Original assignee: Canon Inc
Current assignee: Canon Inc
Priority date: 2014-10-06
Filing date: 2014-10-06
Publication date: 2016-04-13
Anticipated expiration: 2034-10-06
Also published as: GB2530997B; GB201417613D0

Abstract

Disclosed is a system and method for processing an image in a system comprising a mobile device and a fixed communication device with the mobile device comprising a mobile camera and a communication device. The mobile device is positioned at a first position, 610, which allows a desired image of an object to be captured using the mobile camera. The quality of a wireless communication path between the mobile device and the fixed communication device is then determined, 623. If the determined quality does not meet a quality threshold value, 625, the mobile device is moved to a second position, 630, and an image of the object captured at this second position. An image corresponding to the desired image of the object with the mobile device at the first position is then reconstructed based on the image that has been captured at the second position. The invention can be used in a visual control system in which a mobile camera is used to check operations carried out by a robot.

Description

The present invention relates to a method and a system for processing an image in a system comprising at least one mobile device and at least one fixed communication device, the at least one mobile device comprising at least one mobile image capture device and at least one mobile communication device.

In one particular embodiment, the at least one mobile device communicates with the at least one fixed device via a Wireless Personal Area Network (W-PAN).

The invention has a particular application in a visual control system which is used for example to control an industrial process. For example the visual control system may be used to check the results of an operation such as an assembly step implemented by an industrial robot.

Such an application is illustrated in Figure 1. Figure 1 represents an industrial robot comprising mainly an arm 120, an arm controller 110, a vision controller 190 and a robot brain 100.

In this example, the mobile device is a wireless mobile camera 150 that is fixed at the end of the arm 120, the movements of the arm 120 being controlled by the arm controller 110. The wireless mobile camera 150 may be positioned such that a particular image of an object 160 is acquired. In this example, the object 160 is a camera.

The wireless mobile camera 150 comprises at least one mobile image capture device 130 (video camera or image camera) and at least one mobile communication device 140.

The mobile image capture device 130 is connected to the mobile communication device 140 which transmits to the vision controller 190 the images that have been captured by the mobile image capture device 130.

The vision controller 190 is connected to at least one fixed communication device 180, the fixed communication device 180 comprising means for receiving, via radio waves 170, the image that has been acquired by the mobile image capture device 130.

The vision controller 190 transmits information through a connection to the robot brain 100, the information varying on the basis of the process carried out by the robot.

In one embodiment, the connection 195 is a wired connection.

However, this connection may be wireless.

For example, in the case of a robot used to assemble parts, the information transmitted through the wired connection 195 from the vision controller 190 to the robot brain 100 may be the level of correlation between the captured image and a reference image, allowing thus detection of whether the

assembled object is compliant with specifications.

Wireless Personal Area Networks use millimeter wave frequencies, typically in the 60 GHz band for interconnecting nodes in the network. At those frequencies, electromagnetic signals preferably require a direct transmission without reflection, called Line of Sight (LOS), the spread of these electromagnetic signals being characterized by rapid attenuation of the signal strength.

Figure 2 illustrates the wireless mobile camera 150, the vision controller 190 connected to the fixed communication device 180 and a device or object 160 to be observed.

The mobile image capture device 130 is placed at a distance dl from the mobile communication device 140, the mobile image capture device 130 and the mobile communication device 140 being both fixed together on a frame 210. The frame 210 may be a PCB (Printed Circuit board) or another kind of frame.

The frame 210 is mounted at one end of the arm 120 of the robot in order to be positioned close to the object 160 which is inspected.

According to the example represented by Figure 2, the arm of the robot 120 is positioned along the optical or symmetry axis of the mobile image capture device 130.

In another example, the arm 120 of the robot may be situated in a different position, for example at a distance from the mobile image capture device 130 and along an axis which is parallel to the optical axis of the mobile image capture device 130.

In another example, the arm 120 of the robot is situated along an axis that is misaligned with respect to the optical axis of the mobile image capture device 130.

It may be noted that the mobile image capture device 130 and the mobile communication device 140 are close to each other in order to reduce the length of the electrical connection 220.

The distance dl between the mobile image capture device 130 and the mobile communication device 140 is also reduced as much as possible in order to avoid data corruption, and thus to obtain images with very high quality from the wireless mobile camera 150.

The wireless mobile camera 150 is placed at a distance d2 from the object 160 to inspect. This distance d2 is defined on the basis of optical characteristics of the vision sensor, of the area to shoot and of other constraints such the position of other arms of the robot.

Moreover, in order to be sure to obtain an image of the object 160 and to obtain a good quality image, the distance d2 is commonly limited to a few centimeters or decimeters.

Since values of distances dl and d2 are low compared with the dimension of the object 160 to observe, it may occur that the object 160 is in the Line Of Sight (LOS) between the mobile communication device 140 and the fixed communication device 180.

Thus, it may occur that for some positions of the wireless mobile camera 150, the radio beam between the mobile communication device 140 and the fixed communication device 180 is obstructed by the device 160 under scan, making the radio communication more difficult, i.e. increasing the communication duration and/or losing on quality of the captured image, or even making impossible the communication by radio between the mobile communication device 140 and the fixed communication device 180.

Document US2009/073270 describes a method for efficiently transferring data from an electronic camera device. Captured image data are temporarily stored into a local buffer memory that is embedded in the electronic camera device.

However, this solution slows down the operation of the robot since image capture and image transfer operations are implemented from different positions of the arms.

The present invention is directed to providing a method for processing an image in a system comprising at least one mobile device and at least one fixed communication device, providing improved reception in the fixed communication device of images of good quality, without slowing down the system.

To that end, according to a first aspect, the present invention concerns a method for processing an image in a system comprising at least one mobile device and at least one fixed communication device, the mobile device comprising at least one mobile image capture device and at least one mobile communication device, the image being captured by the mobile image capture device According to the invention, the method comprises: -determining a first position of the mobile device, the first position allowing the mobile image capture device to capture a desired image of an object, -determining a quality parameter representing the quality of the communication conditions for wirelessly transmitting an image from the mobile device positioned at the first position to the fixed communication device, -assessing the determined quality parameter by comparison with a quality threshold value, the quality threshold value representing a threshold quality: -in a case where the determined quality does not meet the threshold quality, positioning the mobile device in a second position different from the first position, -capturing an image of the object, -transmitting the captured image to the fixed communication device, and reconstructing an image corresponding to the desired image obtained with the mobile device at the first position, based on the image that has been captured with the mobile device at the second position.

Thus, an image of an object is obtained and then transmitted by the mobile device which is positioned at a second position, the positioning or not of the mobile device at this second position taking into account the communication conditions between the mobile device and the fixed communication device, this second position allowing good transmission conditions.

Since, both capturing and transmitting the image are implemented at the same position (second position), the operation of the system is not slowed down.

Therefore, the desired image that would be captured by the mobile device at the first position is obtained without slowing down the system.

According to an embodiment, the method further comprises modifying the first position and repeating the steps of determining a quality parameter and of assessing the determined quality until the second position is obtained for which the determined quality meets the threshold quality.

According to an embodiment, modifying the first position comprises displacing the mobile device parallel to at least one from among the x-axis, the y-axis and the z-axis, and/or around at least one from among the x-axis, the y-axis and the z-axis, the displacement of the mobile device from the first position to the second position being represented by a set of parameters.

According to an embodiment, reconstructing the desired image comprises modifying the captured image according to parameters representing the displacement of the mobile device from the first position to the second position.

In particular, modifying the captured image according to parameters is based on a reverse displacement of the mobile device from the first position to the second position.

According to an embodiment, the first position and the second position of the mobile device comprise coordinates according to an x-axis, an y-axis and z-axis representing the optical center of the mobile image capture device.

It may be noted that in such an embodiment, the position of the mobile device and the position of the mobile image capture device are identical.

According to an embodiment, the set of parameters representing the displacement of the mobile device from the first position to the second position are transmitted to a vision controller that is connected to the fixed communication device.

According to an embodiment, reconstructing the desired image is implemented by a vision controller according to the parameters representing the displacement of the mobile device from the first position to the second position.

Thus, the vision controller reconstructs the desired image that would be captured by the mobile device at a first position, based on the image which is obtained by the mobile device positioned at a second position.

Thus, the mobile device does not need of supplementary means (for instance image buffer) and its cost is not increased.

According to another embodiment, reconstructing the desired image is implemented by the mobile device before transmitting the desired image to the fixed communication device.

According to an embodiment, the quality parameter representing the communication conditions comprises a predetermined period of time, the period of time representing a maximum period of time for the reception of an image by the fixed communication device.

According to another example, the quality parameter representative of the communication conditions comprises a Radio Signal Strength Indication, a Signal to Noise Ratio, a Bit Error Rate or an Error Vector Magnitude.

According to an embodiment, the second position is pre-defined according to an operation to implement or a time parameter relative to the system.

Therefore, time is saved since steps of determining a quality parameter and of assessing the determined quality parameter are only implemented during a phase] named learning phase.

According to a second aspect of the invention, there is provided a system for processing an image comprising at least a mobile device and a least a fixed communication device, the mobile device comprising at least one mobile image capture device and at least one mobile communication device, the image being captured by the mobile image capture device, the system further comprising: -means for determining a first position of the mobile device, the first position allowing the mobile image capture device to capture a desired image of an object, -means for determining a quality parameter representative of the quality of communication conditions for wirelessly transmitting an image from the mobile device positioned at the first position to the fixed communication device, -means for assessing the determined quality parameter by comparison with a quality threshold value, the quality threshold value representing a threshold quality, -means for positioning the mobile device in a second position different from the first position, in a case where the determined quality does not meet the threshold quality, -means for capturing an image of the object, -means for transmitting the captured image to the fixed communication device, and -means for reconstructing an image corresponding to the desired image obtained with the mobile device at the first position based on the image that has been captured with the mobile device at the second position.

According to an embodiment, the system further comprises means for modifying the first position and means for assessing a quality until the second position is obtained for which a determined quality meets the threshold quality.

B

According to an embodiment, the means for modifying the first position comprises means for displacing the mobile device parallel to at least one from among the x-axis, the y-axis and the z-axis, and/or around at least one from among the x-axis, the y-axis and the z-axis, the displacement of the mobile device from the first position to the second position being represented by a set of parameters.

According to an embodiment, the means for reconstructing the desired image comprises means for modifying the captured image according to parameters representing the displacement of the mobile device from the first position to the second position.

According to an embodiment, the system further comprises means for transmitting the set of parameters representing the displacement of the mobile device from the first position to the second position to a vision controller that is connected to the fixed communication device.

According to a third aspect of the present invention, there is provided a means for storing information which can be read by a computer or a microprocessor holding instructions of a computer program, for implementing a method for processing an image according to the invention, when said information is read by said computer or said microprocessor.

The means for storing is partially or totally removable.

According to a fourth aspect of the present invention, there is provided a computer program product which can be loaded into a programmable apparatus, comprising a sequence of instructions for implementing a method for processing an image according to the invention when said computer program product is loaded into and executed by said programmable apparatus.

The advantages and particular features of the system for processing an image, of the means for storing information and the computer program product are similar to those of the method for processing an image.

Still other features and advantages of the invention will appear in the following description, made with reference to the accompanying drawings which are given by way of non-limiting example, and in which: -Figure 1 represents a system comprising a wireless mobile camera according to the invention; -Figure 2 and Figure 3 illustrate a problem solved by the present invention; -Figures 4 illustrates a proposed solution according to an embodiment of the invention; -Figure 5 illustrates in a general form a proposed solution according to the invention; -Figure 6 illustrates flowcharts followed by the brain and the vision controller according to an embodiment of the invention; and -Figure 7 represents a schematic block diagram of a particular hardware configuration of a device suitable for implementation of a method according to the invention.

The problem solved by the present invention is recalled here in reference to Figure 3.

Figure 3 illustrates schematically the problem found when transmitting an image from the mobile device 150 to the fixed communication device 180. The mobile device is, in an embodiment, a wireless mobile camera 150.

In particular, Figure 3 represents schematically the elements of the system illustrated in Figure 2 according to a 2 dimensional side view, a 2 dimensional top view and a 3 dimensional view.

As explained below, in a general case, the distance dl between the mobile image capture device 130 and the mobile communication device 140, and distance d2 between the mobile image capture device 130 and the object to inspect are low compared to the dimensions of the object 160 to inspect.

In the example represented by Figure 3, the wireless mobile camera is positioned in a vertical position such that the mobile image capture device 130 and the mobile communication device 140 are aligned with a vertical axis (y-axis).

In the represented example, the mobile image capture device 130 captures a desired image 300 of the object 160.

Once the desired image 300 has been captured, the image data is transferred to the mobile communication device 140 which transmits the data to the fixed communication device 180.

As illustrated by Figure 3, the object 160 to inspect is situated in the Line Of Sight between the mobile communication device 140 and the fixed communication device 180. As explained above the radio waves 170 from the mobile communication device 140 cannot reach the fixed communication device and the transmission of the image data cannot be achieved satisfactorily.

Figure 4 represents schematically a solution provided by the method of processing an image that solves the problem illustrated in Figure 3.

In Figure 4, the mobile image capture device 130 and the mobile communication device 140 are aligned with a horizontal axis z (z-axis). Thus, the mobile camera 150 is positioned in a second position that is different that the first position represented in Figure 3. In this example, the wireless camera 150 has been rotated by 9Q0 around the x-axis and in a plane formed by the y- axis and a z-axis (i.e. an axis that is perpendicular to the y-axis and to the z-axis).

In this second position, the mobile image capture device 130 captures an image 400 of the object 160. Next, the mobile image capture device 130 transmits the captured image 400 to the mobile communication device 140 which transmits the captured image 400 data to the fixed communication device 180.

With the wireless mobile camera 150 positioned in the second position, the Line Of Sight between the mobile communication device 140 and the fixed communication device 180 is not obstructed by the object 160 of interest and the captured image 400 data may be correctly received at the fixed communication device 180.

In one embodiment, once the captured image 400 has been obtained, the desired image 300 is reconstructed on the basis of the captured image 400.

In one embodiment, the reconstruction of the desired image 300 is implemented by the vision controller 190 that is connected to the fixed communication device 180, once the captured image 400 has been received at the fixed communication device 180.

In another embodiment, the reconstruction of the desired image 300 is implemented by the wireless mobile camera 150 before transmitting the image to the fixed communication device 180.

The reconstruction of the desired image 300 comprises modifying the captured image 400 according to parameters representing the displacement of the wireless mobile camera 150 from the first position to the second position.

It may be noted that in the described example, the captured image 400 is square in shape. In this case, the modification of the captured image 400 according to parameters representing the displacement of the wireless mobile camera 150 from the first position to the second position, comprises swapping the x and y coordinates of the pixels constituting the captured image 400.

If the shape of the capture image 400 is not square, for example a rectangular shape, the second position is also determined such that the captured image 400 comprises at least the entirety of the pixels constituting the desired image 300.

In an alternative, the wireless mobile camera 150 comprises a zoom lens allowing capture more or fewer pixels.

Figure 5 represents a general case of the application of the method according to the invention.

The wireless mobile camera 150 is displaced from a first position A to a second position B. The first position A corresponds to the position at which the mobile image capture device 130 would acquire the desired image 300 of the object 160, i.e. the optimal position for acquiring an image of the objet 160 to inspect. The second position B corresponds to the position at which the transmission between the wireless mobile camera 150 and the fixed communication device 180 is satisfactorily possible.

In a general case, the displacement of the wireless mobile camera 150 may be defined by: -parameters Ax, Ay, Az representing respectively the translation movement with respect to the horizontal x-axis, the vertical y-axis, and the z-axis which is perpendicular to both x-axis and y-axis.

-parameters ex, ey, ez representing a rotation of the end of the arm 120 at which the wireless mobile camera 150 is fixed respectively around the x-axis, the y-axis and the z-axis.

According to the described embodiment, the first position A and the second position B of the wireless mobile camera 150 comprise coordinates according to the x-axis, the y-axis and the z-axis representing the optical center of the mobile image capture device 130.

It should be noted that similar to Figure 2, in the described embodiment, the arm 120 of the robot is positioned along the optical or symmetry axis of the mobile image capture device 130.

Thus, the position of the wireless mobile camera 150 coincides with the position of the mobile image capture device 130.

In other embodiments, the arm 120 of the robot may be positioned along a different axis, for example the arm 120 of the robot may be situated at a distance from the mobile image capture device 130 and along an axis which is parallel to the optical axis of the mobile image capture device 130.

In another example, the axis along the arm 120 is situated and the optical axis of the mobile image capture device 130 may be misaligned.

In these embodiments the gap between the coordinates x, y, z of the optical center of the mobile image capture device 130 and the coordinates x, y, z of the wireless mobile camera 150 (represented for example by the position of the arm 120 of the robot) has to be taken into account when reconstructing the desired image 300.

According to example represented by Figure 5, in the first position A, the mobile image capture device 130 is situated at coordinates xO, yO, and zO in the horizontal axis x-axis, the vertical axis y-axis and the z-axis respectively, and in the second position B the mobile image capture device 130 is situated at coordinates xl, yl and zl.

In the example described, the parameter Ax presents a value of xl-xO, the parameter Ay a value of yl -yO, and the parameter Az is equal to zero.

The parameter ex and ey present a value of zero. Only the parameter ez presents a value different from zero since the arm 120 rotates around the z-axis when passing from the first position A to the second position B. The parameters Ax, Ay, Az, Ox, 6 y, 6 z are transferred from the brain 100 to the arm controller 110 in order to implement the displacement of the wireless mobile camera 150 from the first position A to the second position B. In one embodiment, the parameters Ax, Ay, Az, Ox, Oy, ez are also transferred to the wireless mobile camera 150 which uses them in order to generate the desired image 300 on the basis of the captured image 400 and the parameters Ax, Ay, Az, Ox, Oy, Oz.

In another embodiment, the parameters Ax, Ay, Az, Ox, Oy, Oz are transferred to the vision controller 190. The vision controller 190 generates the desired image 300 on the basis of the captured image 400 and the parameters Ax, Ay, Az, Ox, Oy, Oz.

According to an embodiment, the desired image 300 is reconstructed by modifying the captured image 400 according to parameters Ax, Ay, Az, ex, ey, ez representing the displacement of the mobile device 150 from the first position A to the second position B. In particular, the captured image 400 is modified according to parameters Ax, Ay, Az, ex, ey, ez based on a reverse displacement of the mobile device 150 from the first position A to the second position B. An embodiment of the method for processing according to the invention is illustrated in Figure 6. In this embodiment, a first part of the method is implemented by the brain 100 of the system and a second part is implemented by the vision controller 190.

The part of the method implemented by the brain 100 begins with a step of initialization 605 which is directed to initializing the system.

Next, in step 610, the brain 100 requests to the arm controller 110 to put the arm 120 at the first position A. At step 615 the brain 100 checks if a picture or image of the object 160 is required when the arm 120 is positioned at this first position A. If the response is negative, i.e. if no picture is required, there follows a step 640 in which the brain 100 requests another operation, the operation consisting for example in putting the arm 120 at another position. Next, step 615 is implemented again. Thus, the brain 100 waits for a new request to take a picture or image.

If the response in step 615 is affirmative, i.e. if a picture is required, in step 620 the brain 100 requests the vision controller 190 to take a picture or an image of the object 160.

The vision controller 190 requests the wireless camera 150 to take a picture.

Next, in step 623, a quality parameter representing the communication conditions for transmitting an image from the mobile device 150 positioned at the given position, for example the first position A, to the fixed communication device 180 is determined.

In the following step 625, it is checked if the determined quality parameter is acceptable.

In particular, the determined quality parameter is assessed by comparison with a threshold quality value, the quality threshold value representing a threshold quality.

In an embodiment, a quality parameter representing the communication conditions comprises a period of time, and the threshold quality a predetermined period of time representing a maximum period of time for the reception of an image by the fixed communication device 180.

In this embodiment, in step 625, the brain 100 checks if the picture has been received at the vision controller 190 within a predetermined period of time.

In particular, determining 623 the quality parameter comprises determining the period of time needed for the reception of an image to the fixed communication device 180, and assessing 625 the determined quality parameter comprises comparing the period of time required for the reception of the image with the predetermined period of time.

If the response is affirmative, i.e. a picture or captured image 400 is received in the vision controller 190 before the predetermined period of time has elapsed, the step 640 follows in order to implement another operation, for example to put the arm 120 in another position.

In this example, if the determined quality parameter (a period of time) is greater than a threshold quality value (predetermined period of time), i.e. if an image is not received by the vision controller 190 within the predetermined period of time, in step 630, the brain 100 requests the arm controller 110 to set the wireless mobile camera 150 in a new position until a position is attained which makes it possible to obtain an image 400 of the object 160 (the second position B).

Thus, in step 625, the determined quality parameter is compared with a threshold quality value, the threshold quality value representing a quality threshold, the result of this comparison indicating if the position allows both capturing the image 400 by the mobile image capture device 130 and transmitting it at a predetermined quality from the mobile communication device 140 to the fixed communication device 180.

If the result of this comparison is negative, i.e. the position does not allow both capturing and transmitting an image, the position is modified in step 630, and the steps of determining 623 a quality parameter and of comparing 625 are repeated until a position is attained for which the result of the comparison is positive.

According to another embodiment, a quality parameter is a parameter representing the quality of the wireless communication between the mobile communication device 140 and the fixed communication device 180. For example, the quality parameter may be the Radio Signal Strength Indication (RSSI) which represents the signal level at a receiver (here the fixed communication device 180), the Signal to Noise Ratio (SNR), the Bit Error Rate (BER) or the Error Vector Magnitude (EVM).

In this embodiment, in step 625, the brain 100 assesses the determined quality parameter by comparison with the correspondent threshold quality value.

The threshold value for the corresponding parameter represents a threshold quality.

Depending on the type of parameter used to assess communication conditions, a higher or lower value may indicate better quality. Therefore a determination of whether a value is greater than or less than a threshold is made accordingly.

Thus, for example, when the quality parameter is the RSSI or the SNR, the determined quality parameter has to be greater than the threshold quality value in order to meet the threshold quality.

On the contrary, when the quality parameter is the BER or the EVM, the determined quality parameter has to be lower than the threshold quality value in order to meet the threshold quality.

In the affirmative case, step 640 follows and in the negative case, step 630 follows.

The new positions of the wireless mobile camera 150 may be determined in several ways.

According to a preferred embodiment, the displacements of the wireless mobile camera 150 are parallel to the x-axis or the y-axis, or comprising a rotation of +1-90° or 180°around z-axis.

According to an embodiment, a new position is determined by successively rotating the arm of the robot 120 around the z axis of +90°, rotating around the z axis of -90°, rotating around the z axis of 180°.

These spatial operations can be compensated easily by manipulation of the address of the pixels without having to process the pixels themselves.

If none of the determined new positions permits to meet the threshold quality, the arm 120 of the robot is successively moved along the arc of a circle of radius equal to the distance between the mobile image capture device 130 and the object 160 by steps corresponding to an angle of 10°.

According to another embodiment, the second position B is pre-defined according to an operation to implement or a time parameter relative to the system.

For example, a pre-defined position allowing good communication conditions (second position B) is associated with each step or operation in the functioning of the industrial robot. Thus, the wireless mobile camera 150 is positioned in a pre-defined position that allows the fixed communication device to correctly receive an image from the mobile communication device 140.

That embodiment has the advantage of save time as there is no need to look for the right position again.

According to an embodiment, the predetermined position of the wireless mobile camera 150 is manually programed by an operator during the programming phase of the industrial robot.

Next] in the following step 635 the brain 100 informs the vision controller 190 about the displacement of the wireless mobile camera 150 by transferring it the parameters Ax, Ay, Az, ex, ey, 9z.

Next, step 620 is implemented in order to request to the vision controller 190 to obtain an image of the object 160 to inspect.

Step 620 is followed, as indicated here-above, by step 623.

The loop comprising steps 620, 623, 625, 630 and 635 is repeated until an image is received.

Thus, when in step 625 it is checked that an image is received to the fixed communication device 180 and that the determined quality meets the threshold quality, step 640 is implemented in order to implement another operation, the wireless mobile camera 150 going to a new position.

In the second part of the method for processing that is implemented by the vision controller 190, a step of initialization 650 is directed to initializing the system.

Next, in step 655, the vision controller 190 checks if a picture or image of the object 160 is required by the brain 100. In a negative case, the vision controller 190 returns to the step following the initialization step 650.

In an affirmative case, in step 660 a variable Nb_ofjrials is initialized, for example to zero, this variable Nb_of_trials recording the number of times that the vision controller 190 has requested to the wireless mobile camera 150 to obtain an image.

Next, in step 665, the vision controller 190 requests the wireless mobile camera 150 to take an image and in step 670 the variable Nb_of_trials is incremented.

Next, in step 675 the vision controller 190 checks if an image has been received from the wireless mobile camera 150.

If the response is positive, in step 680 the captured image 400 is processed taking into account the displacement information concerning the wireless mobile camera 150. This information is received from the brain 100.

The displacement information comprises the parameters Ax, Ay, Az, ex, ey, Bz.

Thus, in step 680, the desired image 300 is reconstructed on the basis of the captured image 400 received in the vision controller 190 and taking into account the displacement information.

In an example, if the wireless mobile camera 150 has been rotated by 9Q0 to enable the wireless communication (such as described in reference to Figures 3 and 4), a signal processing unit of the vision controller 190 applies an operation consisting in swapping the x and y coordinates. Once the desired image 300 has been reconstructed, it is for example transferred to the brain 100 in step 685.

If the response in step 675 is negative, the vision controller 190, in a step 690, compares the value of the variable Nb_of_trials with a predetermined threshold.

If the value of the variable Nb_of_trials is below the predetermined threshold, the vision controller 190 returns to the step 665 and again requests the wireless mobile camera 150 to acquire an image.

If the value of the variable Nb_ofjrials is above the predetermined threshold, the vision controller 190 returns to the step 655 and waits for a new request from the brain 100 to take a picture (step 620).

It may be noted that in another embodiment the step 680 in which the desired image 300 is reconstructed is not implemented by the vision controller but by the brain or by the wireless mobile camera 150. In the case where the wireless mobile camera 150 reconstructs the desired image 300, the image that has been received by the vision controller 190 corresponds to the desired image 300.

Figure 7 is a schematic block diagram of a computing device 700 suitable for implementing one or more embodiments of the invention. The computing device 700 may be embodied in each device of the system, i.e. in the mobile device 150, the vision controller 190, the fixed communication device 180, the brain 100 or the arm controller 110 The computing device 700 may be a programmable computing machine, such as a PC ("Personal Computer"), a DSP ("Digital Signal Processor") or a microcontroller; or else implemented in hardware by a machine or a dedicated component, such as an FPGA ("Field-Programmable Gate Array") or an ASIC ("Application-Specific Integrated Circuit"). Any step of the method for processing an image which is shown in Figure 6 may be implemented in software by execution of a set of instructions or program by the computing device 700.

The computing device 700 comprises among others a central processing unit 701 (designated CPU in the drawing) which executes the instructions relative to the implementation of embodiments of the method for processing an image. The instructions are stored in a Read Only Memory (ROM) 702 or in other storage means. On powering up, the programs which are stored in a non-volatile memory, for example the ROM 702, are transferred into the Random Access Memory RAM 703, which will then contain the executable code of embodiments of the method for processing an image, as well as registers for storing the variables necessary for implementing the invention. In a variant, the program or programs may be received in order to be stored in an identical fashion to that described previously via the communication network 704. The computing device 700 may also comprise a data storage means 706 such as a hard disk, for storing computer programs for implementing methods of one or more embodiments of the invention and data used or produced during the implementation of one or more embodiments of the invention.

In more general terms, an information storage means, which can be read by a computer or microprocessor, integrated or not into the device, and which may possibly be partially or totally removable stores a program implementing the method for processing an image according to the invention.

A communication bus 705 enables communication between the different elements included the computing device 700. The representation of the communication bus 705 is non-limiting and, in particular, the central processing unit 701 may communicate instructions to any element of the computing device 700 directly or by means of another element.

The computing device 700 also comprises a hard disk 706, used by the central processing unit 701 in a conventional manner via the communication bus 705.

The computing device 700 further comprises a communication interface 709 linked to the network 704 adapted to transmit digital data in the context of the implementation of the invention. The communication interface 709 is typically connected to a communication network over which digital data to be processed are transmitted or received. The communication interface 709 can be a single communication interface, or composed of a set of different communication interfaces (for instance wired and wireless interfaces, or different kinds of wired or wireless interfaces). Data packets are written to the communication interface for transmission or are read from the communication interface for reception under the control of the software application running in the CPU 701.

The computing device 700 further comprises elements for interface with the user (for receiving inputs from a user or to display information to a user), and in particular a keyboard 707 as well as a screen 708.

The computing device 700 can be connected to various peripherals, such as for example a digital camera 714 or a micro-phone 716, each being connected to an input/output module 712. The inputloutput module 712 receives/sends data from/to external devices such as a video source or display.

The executable code may be stored either in read only memory 702, on the hard-disk 706 or on a removable digital medium such as for example a disk. According to a variant, the executable code of the programs can be received by means of a communication network, via the communication interface 709, in order to be stored in one of the storage means of the computing device 700, such as the hard disk 706, before being executed.

The disk 706 can be replaced by any information medium such as for example a compact disk (CD-ROM), rewritable or not, a ZIP disk or a memory card and, in general terms, by an information storage means that can be read by a microcomputer or by a microprocessor, integrated or not into the computing device 700, possibly removable and adapted to store one or more programs whose execution enables the method for processing an image according to the invention to be implemented.

The central processing unit 701 is adapted to control and direct the execution of the instructions or portions of software code of the program or programs according to embodiments of the method for processing an image according to the invention, which instructions are stored in one of the aforementioned storage means.

The device described here and in particular the central processing unit or CPU 701 is capable of executing instructions from main RAM memory 703 relating to a software application after those instructions have been loaded from the program ROM 702 or the hard-disk (HD) 706 for example, in order to implement the method for processing an image according to the invention.

Claims

CLAIMS1. Method for processing an image in a system comprising at least one mobile device (150) and at least one fixed communication device (180), the at least one mobile device (150) comprising at least one mobile image capture device (130) and at least one mobile communication device (140), the image being captured by the mobile image capture device (130), wherein the method comprises: -determining (610)a first position (A) of the mobile device (150), the first position (A) allowing the mobile image capture device (130) to capture a desired image (300) of an object (160), -determining (623) a quality parameter representing the quality of the communication conditions for wirelessly transmitting an image from the mobile device (150) positioned at the first position (A) to the fixed communication device (180), -assessing (625) the determined quality parameter by comparison with a quality threshold value, the quality threshold value representing a threshold quality: -in a case where the determined quality does not meet the threshold quality, positioning (630, 635) the mobile device (150) in a second position (B) different from the first position (A), -capturing (620, 665) an image (400) of the object (160), -transmitting (685) the captured image (400) to the fixed communication device (180), and -reconstructing (680) an image (300) corresponding to the desired image obtained with the mobile device (150) at the first position (A), based on the image (400) that has been captured with the mobile device (150) at the second position (B).
2. Method according to claim 1, further comprising modifying (630, 635) the first position (A) and repeating the steps of determining a quality parameter and of assessing (625) the determined quality until the second position (B) is obtained for which the determined quality meets the threshold quality.
3. Method according to claim 2, wherein modifying (630, 635) the first position (A) comprises displacing the mobile device (150) parallel to at least one from among the x-axis, the y-axis and the z-axis, and/or around at least one from among the x-axis, the y-axis and the z-axis, the displacement of the mobile device (150) from the first position (A) to the second position (B) being represented by a set of parameters (Ax, Ay, Az, Ox, Oy, ez).
4. Method according to any one of claims 1 to 3, wherein reconstructing (680) the desired image (300) comprises modifying the captured image (400) according to parameters (Ax, Ay, Az, ex, ey, ez) representing the displacement of the mobile device (150) from the first position (A) to the second position (B).
5. Method according to claim 4, wherein modifying the captured image (400) according to parameters (Ax, Ay, Az, Ox, Oy, ez) is based on a reverse displacement of the mobile device (150) from the first position (A) to the second position (B) to the captured image (400).
6. Method according to any one of claims 1 to 5, wherein the first position (A) and the second position (B) of the mobile device (150) comprises coordinates (x, y, z) according to an x-axis, an y-axis and an z-axis representing the optical center of the mobile image capture device (130).
7. Method according to any one of claims 3 to 6, wherein the set of parameters (Ax, Ay, Az, Ox, Oy, Oz) representing the displacement of the mobile device (150) from the first position (A) to the second position (B) are transmitted to a vision controller (190) that is connected to the fixed communication device (180).
8. Method according to claim 7, wherein reconstructing the desired image (300) is implemented by the vision controller (190) according to the parameters (Ax, Ay, Az, Ox, Oy, Oz) representing the displacement of the mobile device (150) from the first position (A) to the second position (B).
9. Method according to any one of claims 3 to 6, wherein reconstructing the desired image (300) is implemented by the mobile device (150) before transmitting the desired image (300) to the fixed communication device (180).
10. Method according to any one of claims 1 to 9, wherein a quality parameter representing the communication conditions comprises a predetermined period of time, the period of time representing a maximum period of time for the reception of an image by the fixed communication device (180).
11. Method according to any one of claims 1 to 9, wherein a quality parameter representative of the communication conditions comprises a Radio Signal Strength Indication (RSSI), a Signal to Noise Ratio (SNR), a Bit Error Rate (BER) or an Error Vector Magnitude (EVM).
12. Method according to any one of claims 1 to 11, wherein the second position (B) it is pre-defined according to an operation to implement or a time parameter relative to the system.
13. System for processing an image comprising at least a mobile device (150) and a least a fixed communication device (180), the mobile device (150) comprising at least one mobile image capture device (130) and at least one mobile communication device (140), the image being captured by the mobile image capture device (130), wherein the system further comprises: -means for determining (610) a first position (A) of the mobile device (150), the first position (A) allowing the mobile image capture device (130) to capture a desired image (300) of an object (160), -means for determining a quality parameter representative of the quality of communication conditions for wirelessly transmitting an image from the mobile device (150) positioned at the first position (A) to the fixed communication device (180), -means for assessing the determined quality parameter by comparison with a quality threshold value, the quality threshold value representing a threshold quality, -means for positioning the mobile device (150) in a second position (B) different from the first position (A), in a case where the determined quality does not meet the threshold quality, -means for capturing (620) an image (400) of the object (160), -means for transmitting (685) the captured image (400) to the fixed communication device (180), and -means for reconstructing an image (300) corresponding to the desired image obtained with the mobile device (150) at the first position (A), based on the image (400) that has been captured with the mobile device (150) at the second position (B).
14. System for processing an image according to claim 13, further comprising means for modifying the first position and means for assessing a quality until the second position is obtained for which a determined quality meets the threshold quality.
15. System for processing an image according to claim 14, wherein means for modifying the first position comprises means for displacing the mobile device (150) parallel to at least one from among the x-axis, the y-axis and the z-axis, and/or around at least one from among the x-axis, the y-axis and the z-axis, the displacement of the mobile device (150) from the first position (A) to the second position (B) being represented by a set of parameters (Ax, Ay, Az, ex, ey, ez).
16. System for processing an image according to any one of claims 13 to 15, wherein means for reconstructing the desired image (300) comprises means for modifying the captured image (400) according to parameters (Ax, Ay, Az, 9x, ey, ez) representing the displacement of the mobile device (150) from the first position (A) to the second position (B).
17. System for processing an image according to claims 15 and 16, further comprising means for transmitting the set of parameters (Ax, Ay, Az, ex, ey, ez) representing the displacement of the mobile device (150) from the first position (A) to the second position (B) to a vision controller (190) that is connected to the fixed communication device (180).
18. Means for storing information which can be read by a computer or a microprocessor holding instructions of a computer program, for implementing a method for processing an image according to any one of claims 1 to 12, when said information is read by said computer or said microprocessor.
19. Means for storing information according to claim 18, being partially or totally removable.
20. Computer program product which can be loaded into a programmable apparatus, comprising a sequence of instructions for implementing a method for processing an image to any one of claims 1 to 12, when said computer program product is loaded into and executed by said programmable apparatus.
21. Method for processing an image substantially as hereinbefore described with reference to, and as shown in, Figure 6 of the accompagnying drawings.
22. System for processing an image substantially as hereinbefore described with reference to, and as shown in, Figure 1 of the accompagnying drawings.