A resolution-adjustable linear scanning device

Abstract

The present application relates to a kind of linear scanning device with adjustable resolution, including the scanning module with several scanning units, scanning unit can be locally imaged to scanning object to generate local image with overlapping area to make scanning module panoramic imaging to scanning object, several scanning units are periodically and / or non-periodically arranged along the first direction to form scanning module, so that the local image generated by scanning module in the first direction has different size overlapping area with its adjacent local image, several scanning units are periodically and / or non-periodically arranged along the second direction to collect local image to make several local images collected by scanning module along the second direction at least have different size overlapping area.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of image acquisition and image processing, and particularly relates to a linear scanning device with adjustable resolution. BACKGROUND

[0002] Image stitching refers to a technology of stitching two or more images with overlapping parts into a panoramic image or a high-resolution image. Image stitching has two steps: image alignment and image blending.

[0003] In the prior art, a device for imaging a partial field of view, a multi-aperture imaging device and a method of providing the same are provided in the patent document with the publication number CN110754081A, wherein each optical channel comprises optical means for projecting a partial field of view of a total field of view onto an image sensor region of an image sensor. A first optical channel of the array is configured to image a first partial field of view of the total field of view. A second optical channel of the array is configured to image a second partial field of view of the total field of view. The device comprises a computing unit configured to obtain image information of the first partial field of view and the second partial field of view based on the imaged partial fields of view, to obtain image information of the total field of view, and to combine the image information of the partial fields of view with the image information of the total field of view to produce combined image information of the total field of view.

[0004] A method and apparatus for capturing a high resolution photograph of a target are provided in the patent document with the publication number CN1287588A, which shifts a focal zone of a linear image sensor array through the entire area of the target to be photographed, the shift can be angular or linear, with appropriate scaling, to produce a final photograph, by varying the depth of focus, the relief of the target can be completely focused in one or more passes.

[0005] The above-mentioned scheme improves the resolution of the image to some extent, but does not fully consider the registration error that occurs in the actual stitching process, and the stitching line is roughly on the same extension line, which is more easily visually distinguished, and the registration of the details such as text and stripes is more difficult, which can cause stitching errors in the above-mentioned details.

[0006] In addition, on the one hand, there are differences in the understanding of those skilled in the art, and on the other hand, the inventors have studied a large number of literatures and patents when making the present application, but due to the limited space, all the details and contents are not listed in detail, which does not mean that the present application does not have the characteristics of the prior art, on the contrary, the present application has all the characteristics of the prior art, and the applicant reserves the right to add relevant prior art in the background art. SUMMARY

[0007] The application discloses a resolution-adjustable linear scanning device, comprising a scanning module configured with a plurality of scanning units, the scanning units being capable of locally imaging a scanning object to generate local images with overlapping regions so that the scanning module performs panoramic imaging on the scanning object, the plurality of scanning units being periodically and / or aperiodically arranged along a first direction to form the scanning module, so that the local images generated by the scanning module in the first direction have different sizes of overlapping regions with adjacent local images, and the plurality of scanning units periodically and / or aperiodically collect local images along a second direction so that the plurality of local images collected by the scanning module along the second direction have at least different sizes of overlapping regions.

[0008] Most of the scanning devices in the prior art splice a plurality of local images with the same size and the same size of overlapping regions to obtain a panoramic image of the scanning object with higher resolution. The local images collected for splicing the panoramic image are generally selected to have the same size (or approximately the same size) and equal size of overlapping parts of adjacent local images collected by the same scanning unit along a stepping direction (or the scanning units are arranged at equal intervals so that adjacent local images are collected by adjacent scanning units). When the local images collected in the above manner are spliced, registration is performed based on the overlapping parts, an optimal splicing line is selected for splicing, and then a fusion algorithm (such as wavelet change, fuzzy inference, etc.) is used to make the adjacent local images naturally transition near the splicing line. The characteristics of small scale change of the local images to some extent reduce the difficulty of splicing, simplify the calculation amount of registration and fusion in the image splicing process, and greatly reduce the visual difference between the adjacent local images and the visual difference between the two sides of the splicing seam. However, the collected images have the same size and approximately equal size of overlapping regions, so that the overlapping regions are on the same extension line, the processing algorithm of the overlapping regions is consistent, and therefore the overlapping regions have similar picture features and are different from the non-overlapping regions, which makes the overlapping regions more easily identified in vision and more easily observed in vision, thereby affecting the splicing effect. Therefore, the periodic or aperiodic collection method adopted by the application disperses the overlapping regions (splicing seams), avoids the overlapping regions with similar picture features on the same extension line after being processed based on the same algorithm, and effectively weakens the visual difference caused by splicing, thereby improving the picture imaging effect.

[0009] In the process of registration fusion, the panoramic image is spliced by several local images, although the existing registration technology can reduce the error caused by the splicing of adjacent local images, but the error cannot be completely eliminated, and the error will gradually accumulate when splicing multiple images in the same extension direction, thus generating an overall error, which is the result of the accumulation of small errors, which is easy to be visually perceived and thus affects the imaging effect, therefore, the non-periodic image acquisition method of the present application can disperse the overall error caused by the registration splicing process to the entire picture or the area which is not easy to be visually perceived (such as the edge of the painting and the blank part between the lines of the text work, etc.), so as to disperse the error of splicing registration to the extent that the observer cannot perceive, so as to weaken the visual difference caused by the overall error.

[0010] Further, in the process of imaging the partial scanning object (such as a painting), multiple scanning is required to ensure the imaging effect. Therefore, the processing module of the present application is not limited to the above-mentioned parameters for the initial scanning result, and the processing module can also identify the contour line and the defect site of the scanning object. In the final scanning process, the overlapping area of the local image is matched with the contour line, and the overlapping area is as much as possible on the contour line, and the splicing line of the fused image is mainly concentrated on the contour line, so that the visually distinguishable splicing line caused by image splicing and the visual splicing trace caused by multiple overlapping areas are fused into the contour line of the picture itself.

[0011] When scanning, the small-scale distortion of the pre-scanning object itself or the small-scale convexity or concavity defect caused by the fact that the pre-scanning object cannot be flatly attached to the scanning platform makes the area of the above-mentioned defect lose picture details and affect the scanning effect, and the multiple scanning sub-units arranged non-periodically in the present application can collect the details of the above-mentioned defect area multiple times under the condition of small angle deviation, and the details of the defect site in the overlapping area can be fused in the process of local image registration and fusion, thereby improving the scanning quality.

[0012] There are certainly multiple regions with different processing difficulties in the picture of the to-be-scanned object (such as the edges of the painting and calligraphy works and the blank parts between lines of the calligraphy works, the image difference between different local images is small in the regions, and the part rich in characters has a large difference between the characters and the background where the characters are located, and the details of the characters make small differences affect the visual effect and cause the eye-recognizable splicing misplacement problem, and thus a higher splicing precision is required), and the same acquisition mode or registration fusion method cannot realize fast and high-resolution acquisition of the target, such as taking a higher-precision acquisition and splicing method to process the regions such as edges that do not contain important features, which further increases the amount of acquired data and thus increases the calculation amount, causing unnecessary time and computing power waste, and reducing the precision causes the problems of character content misplacement, character blurring and other problems affecting the visual effect in the character part.

[0013] Therefore, the non-periodic acquisition mode adopted by the present application can adopt different acquisition modes for regions with different processing difficulties of the pre-scanned object, increase the acquisition density of the part such as the character part which has more precise splicing requirements, so that the adjacent local images of the character part have larger overlapping regions, further improve the registration precision of the adjacent local images, and reduce the acquisition density of the regions with higher similarity and lower processing difficulty, reduce the size of the overlapping region and thus reduce the data acquisition amount and processing calculation amount, and based on the same data processing method, different processing difficulty regions can achieve their predetermined processing effect, and by differentially acquiring different regions in the acquisition process, the factors affecting the picture effect are preprocessed in the acquisition process, reducing the difficulty of subsequent registration fusion.

[0014] Preferably, the linear scanning device further comprises an illumination module and a data processing module, the illumination module comprises a plurality of light emitting units for providing illumination, and the light emitting units are periodically or non-periodically arranged along the first direction and / or the second direction.

[0015] Preferably, during the stepping of the scanning module along the second direction, the data processing module can adjust the spacing between adjacent scanning units of the scanning module based on the preprocessing of the local image information acquired by the scanning unit.

[0016] Preferably, the data processing module can adjust the scanning parameters of the scanning module based on the preprocessing of the local image information so that the local images have different sizes of overlapping regions during the stepping of the scanning module along the second direction.

[0017] Preferably, the scanning parameters at least include the stepping speed and the Z-axis height of the scanning unit.

[0018] Preferably, the preprocessing of the local image information by the data processing module at least includes calculating the frequency domain information, brightness information and color information of the local image.

[0019] Preferably, the data processing module is capable of setting the scanning parameters based on the information inputted by the operator.

[0020] Preferably, the scanning unit is capable of collecting partial images of the scanning object to form a partial image array in digital form related to the scanning object, and a plurality of overlapping areas in the partial image array are capable of being arranged periodically and / or non-periodically.

[0021] Preferably, the data processing module is capable of processing the intersection area of the image with the first resolution and the image with the second resolution, so that the data processing module is capable of realizing the registration of a plurality of partial images with the intersection area based on the image processing of the intersection area. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a simplified overall structure schematic diagram of the resolution-adjustable linear scanning device of the present application;

[0023] Figure 2 is a partial image collection and splicing structure schematic diagram in the prior art;

[0024] Figure 3 is a partial image collection and splicing structure schematic diagram of the resolution-adjustable linear scanning device of the present application.

[0025] LIST OF REFERENCE NUMBERS

[0026] 1: scanning module; 2: scanning object; 3: data processing module; 10: scanning unit; 11: first scanning unit; 12: second scanning unit; 13: third scanning unit; 21: first direction; 22: second direction; 40: first partial image; 41: second partial image; 42: third partial image; 50: fourth partial image; 60: fifth partial image; 70: third overlapping area; 71: fourth overlapping area; 80: first overlapping area; 81: second overlapping area; 101: best view angle range; 200: partial image array. DETAILED DESCRIPTION

[0027] The present application will be described in detail below with reference to the accompanying drawings.

[0028] As Figure 1The present invention discloses a resolution-adjustable linear scanning device, including a scanning module 1 configured with a plurality of scanning units 10, an illumination module (not shown in the figure), and a data processing module 3. The scanning units 10 are capable of performing local imaging on the scanned object 2 to generate local images with overlapping regions so that the scanning module 1 can perform panoramic imaging on the scanned object. The illumination module includes a plurality of light-emitting units for providing illumination. The light-emitting units are arranged periodically or non-periodically along a first direction and / or a second direction. The plurality of scanning units 10 are arranged periodically and / or non-periodically along the first direction 21 to form the scanning module 1, so that the local image generated by the scanning module 1 in the first direction has an overlapping region of different size with its adjacent local images.

[0029] Optionally, the illumination module is disposed on the scanning module 1, and the light-emitting units are distributed near the scanning unit 10, so that the light from the light-emitting units can be projected onto the scanning object 2, and the light from the light-emitting units is reflected by the scanning object 2 and captured by the scanning unit 10.

[0030] like Figure 2 As shown, during the imaging process of scanning module 1, the magnification of the central area and the edge area of ​​the lens of scanning unit 10 are inconsistent, resulting in distortion at the imaging edges. When scanning using scanning unit 10, the larger the field of view and the shorter the focal length of the lens used, the more obvious the distortion becomes, resulting in distorted edges and other parts that are not convenient for stitching. Therefore, the scanning object 2 can be imaged according to the optimal viewing angle range 101 of scanning module 1. During the arrangement of scanning units 10 in the first direction 21, the optimal viewing angle range 101 of scanning units 10 can cover the scanning object 2 to remove distorted edges in the imaging. When stitching multiple images acquired by scanning module 1, the overlapping parts between multiple images are registered and fused to form a final panoramic image containing multiple images. The aforementioned overlapping parts specifically refer to the overlapping parts of multiple images formed within the optimal viewing angle range 101.

[0031] To facilitate the description of the image acquisition process used for stitching, the relative movement direction of the scanning module 1 and the scanning object 2 is set as the second direction 22, and the direction forming a certain angle with the second direction 22 is set as the first direction 21. Preferably, the second direction 22 is perpendicular to the first direction 21. Several scanning units 10 can cover the scanning object 2 with a full field of view in the first direction 21, and perform full-area image acquisition of the scanning object 2 along the second direction 22.

[0032] like Figure 3The image acquired by the first scanning unit 11 of the scanning module 1 shown is the first partial image 40, the image acquired by the second scanning unit 12 is the second partial image 41, and the image acquired by the third scanning unit 13 is the third partial image 42. The overlapping area of ​​the first partial image 40 and the second partial image 41 is the first overlapping area 80, the overlapping area of ​​the second partial image 41 and the third partial image 42 is the second overlapping area 81, the overlapping area of ​​the first partial image 40 and the fourth partial image 50 is the third overlapping area 70, and the overlapping area of ​​the fourth partial image 50 and the fifth partial image 60 is the fourth overlapping area 71.

[0033] Taking the first scanning unit 11 as an example, during the linear stepping process along the second direction 22, the images acquired by the first scanning unit 11 are the first local image 40, the fourth local image 50 and the fifth local image 60 in sequence. The overlapping area of ​​the first local image 40 and the fourth local image 50 is the third overlapping area 70, and the overlapping area of ​​the fourth local image 50 and the fifth local image 60 is the fourth overlapping area 71.

[0034] Example 1

[0035] like Figure 3 As shown, in the prior art, a linear array is used to scan the object (letters, paintings, etc., containing text and images on paper or other materials) in an equally spaced stepping manner. This ensures that the multiple images acquired for stitching have the same size, and the overlapping area between adjacent images acquired by the same scanning unit along the stepping direction is equal in size, facilitating image stitching. The equally spaced arrangement of the scanning units 10 and the equally spaced arrangement of the light sources ensures that the scanned object 2 is under the same or similar lighting conditions, and panoramic images of the scanned object 2 are acquired at the same stepping speed. The acquired images have the same size and lighting conditions, and the overlapping area has the same size, reducing the parameter differences of the acquired images to facilitate stitching. However, the overlapping area of ​​the stitched image is roughly on the same extension line, which easily leads to visually noticeable stitching marks. Furthermore, the errors generated during stitching are easy to accumulate, resulting in more noticeable errors at the edges of the later stitched parts. Therefore, this invention disperses the overlapping area by changing the overlapping area size of multiple scanning sub-units through periodic or non-periodic acquisition methods.

[0036] Preferably, the scanning unit 10 can acquire local images of the scanned object 2 to form a local image array 200 related to the scanned object 2 in digital form, wherein several overlapping regions in the local image array 200 can be arranged periodically and / or non-periodically.

[0037] In particular, during the stepping of the scanning module 1 along the second direction 22, the data processing module 3 is capable of adjusting the spacing between adjacent scanning units 10 of the scanning module 1 based on its pre-processing of the local image information acquired by the scanning units 10, and the data processing module 3 is capable of adjusting the scanning parameters of the scanning module 1 based on its pre-processing of the local image information such that the local images acquired by the scanning module 1 along the second direction 22 have different sized overlapping regions during the stepping of the scanning module 1 along the second direction 22.

[0038] Preferably, the scanning units 10 acquire local images along the second direction periodically and / or aperiodically such that the local images acquired by the scanning module 1 along the second direction have at least different sized overlapping regions.

[0039] Preferably, the scanning parameters comprise at least the stepping speed and the Z-axis height of the scanning units 10.

[0040] Preferably, the pre-processing of the data processing module 3 on the local image information comprises at least the calculation of the frequency domain information, the brightness information and the color information of the local images.

[0041] Preferably, the data processing module 3 is capable of setting the scanning parameters based on information inputted by an operator.

[0042] Preferably, the linear scanning device further comprises an illumination module and a data processing module, the illumination module comprises a plurality of light emitting units for providing illumination, the light emitting units are arranged periodically or aperiodically along the first direction and / or the second direction.

[0043] Preferably, during the stepping of the scanning module along the second direction, the data processing module is capable of adjusting the spacing between adjacent scanning units of the scanning module based on its pre-processing of the local image information acquired by the scanning units.

[0044] Preferably, the data processing module 3 is capable of processing the overlapping region of the image having the first resolution and the image having the second resolution such that the data processing module 3 is capable of achieving the registration of the plurality of local images having the overlapping region based on the image processing of the overlapping region.

[0045] Embodiment 2

[0046] According to a preferred embodiment, when scanning, small-scale defects such as small-scale twists of the scanning object 2 itself or small-scale protrusions or depressions caused by the fact that the scanning object 2 cannot be flatly attached to the scanning platform cause the loss of picture details in the area where the defects are located, affecting the scanning effect. However, in the present application, the non-periodic arrangement of multiple scanning subunits can collect the details of the defect area multiple times under a smaller angle deviation, and by adjusting the Z-axis height, the details of the defect part in the overlapping area can be imaged in a multi-focal manner, thereby realizing fusion in the process of local image registration and fusion and improving the scanning quality.

[0047] Specifically, the part with micro-scale twists has a certain undulation compared to other parts. In the case of fixed focal length scanning, the part with micro-scale twists in the best imaging range of focal length will achieve clear imaging effect, and the image will have obvious edge features and rich details in the spatial domain, and will have more high-frequency components in the frequency domain. However, the imaging of the part outside the best imaging range of focal length will be blurred, and the edge features will be blurred in the spatial domain, and there will be more low-frequency components in the frequency domain. Based on the above characteristics, the data processing module 3 judges the blurred area during image preprocessing and adjusts the Z-axis height of the scanning unit to perform multi-distance imaging at the part with micro-scale twists, or adjusts the distance of the steps, so that several images in the step direction can image the part with micro-scale twists from different angles to adjust the distance of the part with micro-scale twists, so that the part with micro-scale twists can be imaged in multi-focal manner, thereby improving the imaging effect of the part with micro-scale twists.

[0048] According to a preferred embodiment, there are inevitably multiple areas with different processing difficulties in the picture of the object to be scanned (such as the edge of a painting or calligraphy and the blank part between lines of a text work, etc.), and the image difference between different local images is small, while the part rich in text has a large difference between the text and the background where the text is located, and the details of the text cause small differences to affect the visual effect and cause the problem of eye-recognizable misalignment in splicing. Therefore, higher splicing accuracy is required. Based on the same collection method or registration fusion method, it is impossible to quickly and high-resolution collect the target. For example, using a higher-precision collection and splicing method to process the area without important features such as the edge will further increase the amount of collected data, thereby increasing the calculation amount and causing unnecessary time and power waste, and reducing the accuracy will cause problems such as misalignment of text content and blurred text, which affect the visual effect.

[0049] Therefore, the non-periodic acquisition mode adopted by the present application can adopt different acquisition modes for different regions of the pre-scanned object with different processing difficulties, increase the acquisition density of the text part and other parts with more detailed splicing requirements, so that the adjacent local images of the text part have larger overlapping regions, further improve the registration accuracy of the adjacent local images, reduce the acquisition density of the regions with higher similarity and lower processing difficulty, reduce the size of the overlapping region and further reduce the data acquisition amount and processing calculation amount, and based on the same data processing mode, different processing difficulty regions can achieve their predetermined processing effect. By differentiating the acquisition of different regions during the acquisition process, the factors affecting the picture effect are pre-processed during the acquisition process, reducing the difficulty of subsequent registration and fusion.

[0050] Specifically, for the naked eye to observe the region rich in text or with more content changes, it will be felt that the above-mentioned information-containing part has a larger difference with the background where it is located, and the information-containing part is more dispersed, and the information such as the frequency domain information and color information of the corresponding local image changes more obviously. Therefore, the complexity of the picture can be judged during the preprocessing process, so as to adjust the frequency of acquiring local images based on the input information of the operator or the preprocessing result, and further adaptively adjust the acquisition density of the local images according to the difference degree of the picture in the local image, select an appropriate step speed based on the preprocessing result of the previous local image, set multiple acquisition densities, reduce the data processing amount and improve the scanning speed.

[0051] Embodiment 3

[0052] In the imaging process of part of the scanning object (such as a painting), multiple scanning is required in the prior art to ensure the imaging effect. Therefore, the data processing module of the present application is not limited to the content of the above-mentioned embodiments, and the data processing module 3 can also identify the contour line and defect position of the scanning object (using the contour recognition algorithm in the prior art). In the final scanning process, the overlapping region of the local image is matched with the contour line, and the overlapping region is as much as possible on the contour line, and the splicing line of the fused image is mainly concentrated on the contour line, so that the splicing line caused by image splicing and the visual splicing marks caused by multiple overlapping regions are fused into the contour line of the picture itself.

[0053] Specifically, the data processing module 3 is used to perform contour recognition on the panoramic image formed by the initial scanning to extract the contour line of the picture, and the matching fusion is performed in combination with the method of dispersing the splicing seam in Embodiment 1 to adjust the scanning parameters of the scanning module 1.

[0054] Further, in the process of splicing the local images, the overlapping area is mainly used for registration, and then a splicing line is calculated in the range of the overlapping area by using a splicing algorithm, and then the local images are fused based on the splicing line. Based on the above principle, in the process of scanning by the scanning module 1, the contour of the panoramic image obtained by the preliminary scanning has been extracted, and thus the scanning parameters of the scanning module 1 can be adjusted based on the position of the contour line in the image, so that the overlapping part of the local images collected by the scanning module 1 is located at the position of the contour line, and further in the process of re-scanning after the preliminary scanning, the overlapping area of the local images scanned can cover part of the contour line and be distributed at the position of the contour line, so that the splicing line in the process of registration and fusion can be located at the same position as the contour line obtained by the preliminary scanning to a great extent, so as to weaken the splicing trace.

[0055] Further, the contour line is usually an irregular line, and in the process of extracting the contour line, the area in a certain range of the contour line is selected, so that the shape after the selection is similar to the contour frame of the overlapping area, and thus the extracted contour frame can be used as the overlapping area for local image collection. In the process of registration and fusion, since the areas on both sides of the contour line are quite different, the algorithm of the splicing line (least square method, etc.) in the prior art tends to select the area with smaller difference, and usually the contour of the above-mentioned area is distributed along the general trend of the contour line, so that the splicing line can be more consistent with the trend of the contour line in the process of registration and fusion, and the difference on both sides of the splicing line is smaller, so that the fusion of the splicing line and the contour line is more natural.

[0056] In the entire text, the features guided by "preferably" are only optional ways, and should not be understood as necessarily setting, so the applicant reserves the right to abandon or delete the related preferred features at any time.

[0057] It should be noted that the above specific embodiments are exemplary, and those skilled in the art can think of various solutions under the inspiration of the disclosure of the present application, and these solutions also belong to the disclosed range of the present application and fall within the protection scope of the present application. Those skilled in the art should understand that the specification and drawings of the present application are illustrative and do not constitute a limitation on the claims. The protection scope of the present application is defined by the claims and their equivalents.

Claims

1. A resolution-adjustable linear scanning device, comprising a scanning module (1) configured with a plurality of scanning units (10) and a data processing module (3), wherein the scanning units (10) are capable of performing local imaging on a scanned object (2) to generate a local image with overlapping regions, thereby enabling the scanning module (1) to perform panoramic imaging on the scanned object (2). characterized in that A plurality of scanning units (10) are arranged periodically and / or non-periodically along a first direction (21) to form the scanning module (1), so that the local image generated by the scanning module (1) in the first direction has an overlapping region of different size with its adjacent local images. The plurality of scanning units (10) change the size of the overlapping region by periodic or non-periodic acquisition methods to disperse the overlapping region. The data processing module (3) is used to perform contour recognition on the panoramic image formed by the initial scan in order to extract the contour lines of the image. Based on the position of the contour lines in the image, the scanning parameters of the scanning module (1) are adjusted so that the overlapping part of the local image acquired by the scanning module (1) is located at the position of the contour lines.

2. The resolution adjustable line scan apparatus according to claim 1, wherein, The linear scanning device further includes an illumination module, which comprises a plurality of light-emitting units for providing illumination, the light-emitting units being arranged periodically or non-periodically along a first direction and / or a second direction.

3. A resolution adjustable linear scanning device according to claim 2, wherein, During the process of the scanning module (1) stepping along the second direction (22), the data processing module (3) can adjust the spacing between adjacent scanning units (10) of the scanning module (1) based on its preprocessing of the local image information acquired by the scanning unit (10).

4. A resolution-adjustable linear scanning device, comprising a scanning module (1) configured with a plurality of scanning units (10) and a data processing module (3), wherein the scanning units (10) are capable of performing local imaging on the scanned object (2) to generate local images with overlapping regions, thereby enabling the scanning module (1) to perform panoramic imaging on the scanned object. Its features are, Several scanning units (10) periodically and / or non-periodically acquire local images along the second direction so that the several local images acquired by the scanning module (1) along the second direction have overlapping regions of different sizes. The multiple scanning units (10) change the size of the overlapping region through periodic or non-periodic acquisition to disperse the overlapping region. The data processing module (3) is used to perform contour recognition on the panoramic image formed by the initial scan in order to extract the contour lines of the image. Based on the position of the contour lines in the image, the scanning parameters of the scanning module (1) are adjusted so that the overlapping part of the local image acquired by the scanning module (1) is located at the position of the contour lines.

5. The resolution-adjustable linear scanning device according to claim 4, characterized in that, The data processing module (3) can adjust the scanning parameters of the scanning module (1) based on its preprocessing of local image information so that the scanning module (1) has local images of overlapping regions with different sizes during the stepping process of the scanning module (1) along the second direction.

6. The resolution-adjustable linear scanning device according to claim 5, characterized in that, The scanning parameters include at least the stepping speed and Z-axis height of the scanning unit (10).

7. The resolution-adjustable linear scanning device according to claim 6, characterized in that, The data processing module (3) preprocesses the local image information by at least calculating the frequency domain information, brightness information and color information of the local image.

8. The resolution-adjustable linear scanning device according to claim 7, characterized in that, The data processing module (3) can set scanning parameters based on the information input by the operator.

9. A linear scanning device with adjustable resolution, comprising a plurality of scanning units (10) and a data processing module (3), characterized in that, The scanning unit (10) is capable of acquiring local images of the scanned object (2) to form a local image array (200) of the scanned object (2) in digital form. The feature is that several overlapping regions in the local image array (200) can be arranged periodically and / or non-periodically, and the multiple scanning units (10) change the size of the overlapping regions through periodic or non-periodic acquisition methods to disperse the overlapping regions. The data processing module (3) is used to perform contour recognition on the panoramic image formed by the initial scan in order to extract the contour lines of the image. Based on the position of the contour lines in the image, the scanning parameters of the scanning module (1) are adjusted so that the overlapping part of the local image acquired by the scanning module (1) is located at the position of the contour lines.

10. The resolution-adjustable linear scanning device according to claim 9, characterized in that, The data processing module (3) can process the intersection region of the image with the first distinguishability and the image with the second distinguishability, so that the data processing module (3) can realize the registration of multiple local images with the intersection region based on the image processing of the intersection region.

Images