WO2016029822A1

WO2016029822A1 - Star trail shooting processing method and device

Info

Publication number: WO2016029822A1
Application number: PCT/CN2015/087703
Authority: WO
Inventors: 龙浩; 崔小辉; 苗雷; 里强
Original assignee: 努比亚技术有限公司
Priority date: 2014-08-26
Filing date: 2015-08-20
Publication date: 2016-03-03

Abstract

A star trail shooting processing method and device. The method comprises: after star trail shooting is completed, calculating a centre of a circle of a star trail shot this time according to any section of a star trail arc in a synthetic image; and extending, around the centre of a circle, each section of the star trail arc in the synthetic image to acquire a complete star trail effect picture. By means of the method and device in the technical solution of the present invention, a photographer can shoot a complete star trail image in a relatively short time, thereby shortening the shooting time.

Description

Star track shooting processing method and device

Technical field

This paper relates to the field of satellite track processing technology, and in particular to a star track shooting processing method and device.

Background technique

With the development of digital imaging technology, photographers can shoot a variety of scenes, and the star track image is a night view of the photographer. However, when shooting a star track, if you want to capture a complete star track picture, it takes a long time to shoot, and for most photographers, especially amateur photographers, it is difficult to take special time for star track shooting. Therefore, it is necessary to provide a shooting method and apparatus to help the photographer to take a complete star-track image in a short period of time.

Summary of the invention

In view of this, the technical problem to be solved by the present invention is to provide a shooting method and apparatus for solving the problem that the related art star track takes a long time and helps the photographer to shoot a complete star track image in a short time. .

The present invention solves the above technical problems, and the technical solutions adopted are as follows:

A method for processing a star track photograph, comprising the following steps:

After the star track is finished, the center of the star track of the current shooting is calculated according to any segment of the star track in the composite image;

Extending each segment of the star-track arc in the composite image around the center of the circle to obtain a complete star-track rendering.

Optionally, after the star track is finished, the step of calculating the center of the star track of the current shooting according to any segment of the star track in the composite image includes:

Extracting two points on the arc of any of the segments of the star;

Calculating the midpoint of the line with the two points as the endpoint, and confirming through the midpoint and perpendicular to the The vertical line of the line;

Determining an intersection of the perpendicular to the arc of any of the segments;

Matching the two points with a circumference on which the center of the circle is located, finding a circle passing through the two points and the intersection, and determining that the circumference is a trajectory of any of the segments of the star track, The center of the circle is the center of the star track for this shot.

Optionally, the step of extending each segment of the star-track arc in the composite image around the center of the circle to obtain a complete star-track rendering includes:

Identifying a star track zone and a non-star track zone in the composite image;

Each segment of the star track in the composite image is extended around the center of the star in the star track region.

Optionally, the step of identifying the star track zone and the non-star track zone in the composite image includes:

Obtain a range of luminance values of pixels in the star track area;

Performing a row-by-row scan on the pixel points in the star-track image to obtain a brightness value of each pixel point;

Determining whether the magnitude of the luminance value of each pixel is within the range of the luminance value;

If yes, it is determined that the pixel point is a pixel point of the star track area, otherwise, the pixel point is determined to be a pixel point of the non-star track area.

A. Obtain a range of brightness values of pixels in the star track area;

B. Scan the pixels in the star track image row by row to obtain the brightness value of each pixel point;

C. Find, according to the obtained brightness value of each pixel point, a sudden pixel point in which the change of the brightness value in each row of pixels exceeds the first preset threshold;

D. determining that the size of the luminance value between adjacent abrupt pixel points of each row exceeds the number of pixels of the luminance value range and the percentage of the number of all pixel points between the adjacent abrupt pixel points Whether it is greater than a preset second threshold, if yes, determining that a pixel point between the adjacent abrupt pixel points is a pixel point of a non-star-track region, otherwise determining a pixel point between the adjacent abrupt pixel points The pixel point of the star track area.

Optionally, the C step includes:

C1, determining that the first pixel and the last pixel in each row are abrupt pixels, and The first pixel begins to perform step C2;

C2, sequentially calculating an absolute value of a luminance difference between adjacent pixel points, and determining whether an absolute value of a luminance difference between the current pixel point and a subsequent adjacent pixel point exceeds a first preset threshold, and if so, Perform step C3;

C3. Calculate the absolute value of the brightness difference between the current pixel point and the subsequent pixel point in turn, and determine whether the current pixel point is the last pixel point, and if so, stop the calculation, if otherwise, until the absolute value of the brightness difference is less than the first Presetting another pixel point of the threshold, and determining whether the number of N pixel points spaced between the other pixel point and the current pixel point is greater than a third predetermined threshold, and if so, determining the current pixel point and another pixel The point is the abrupt pixel point, and step C2 is continued with another pixel point as the abrupt pixel point.

Optionally, after the step of shooting the star track, calculating the center of the star track of the current shooting according to any segment of the star track in the composite image, the method further includes:

S1, when entering the star track shooting mode, detecting whether the fast shooting mode is turned on;

S2. If the fast shooting mode is turned on, the shooting is stopped when the shooting is performed to a preset time;

S3. Acquire a current composite image.

Optionally, the step S1 includes:

By setting the function of the quick shooting mode to be turned on, the user determines whether to enable the quick shooting mode and set the shooting time of the fast shooting mode according to actual needs.

Optionally, the step S2 includes:

If the quick shooting mode is turned on, the timer is turned on at the beginning of shooting;

Determining whether the timing of the timer reaches a preset time;

Shooting stops if the preset time is reached.

A photographing apparatus comprising a center determining unit and a processing unit, wherein:

The center determining unit is configured to: after the end of the star track shooting, calculate the center of the star track of the current shooting according to any segment of the star track in the composite image;

The processing unit is configured to: surround each segment of the star track arc in the composite image The center of the meta-calculation is extended to obtain a complete star-track rendering.

Optionally, the center determining unit is configured to calculate the center of the star track of the current shooting according to any segment of the star track in the composite image as follows:

Extracting two points on the arc of any of the segments of the star;

Calculating a midpoint of a straight line ending at the two points, and confirming a perpendicular line passing through the midpoint and perpendicular to the straight line;

Optionally, the processing unit is configured to extend each segment of the star-track arc in the composite image around the center of the circle to obtain a complete star-track rendering:

Identifying a star track zone and a non-star track zone in the composite image;

Optionally, the processing unit is configured to identify the star track zone and the non-star track zone in the composite image as follows:

Obtain a range of luminance values of pixels in the star track area;

When it is determined that the size of the brightness value of each pixel is within the range of the brightness value, determining that the pixel point is a pixel point of the star track area, otherwise, determining that the pixel point is a pixel point of the non-star track area .

A. Obtain a range of brightness values of pixels in the star track area;

C. According to the obtained brightness value of each pixel, the change of the brightness value in each row of pixels is found to be super a sudden pixel point of the first preset threshold;

Optionally, the processing unit is configured to: according to the obtained brightness value of each pixel point, find a sudden pixel point in which the change of the brightness value in each row of pixels exceeds the first preset threshold:

C1, determining that the first pixel and the last pixel in each row are abrupt pixels, and performing step C2 from the first pixel;

Optionally, the device further includes a detecting unit and a control unit, wherein

The detecting unit is configured to: detect whether to enable the fast shooting mode when entering the star track shooting mode;

The control unit is configured to: when the detecting unit detects that the quick shooting mode is turned on, control the shooting device to end the star track shooting when the shooting is performed to a preset time.

Optionally, the device further includes a setting unit, wherein

The setting unit is configured to: determine whether to enable the fast shooting mode according to actual needs, and set the shooting time of the fast shooting mode by setting the function button of the fast shooting mode to be turned on.

Optionally, the control unit is configured to control the photographing device to end the star track shooting when the detecting unit detects that the fast shooting mode is turned on when the detecting unit reaches a preset time as follows:

When the quick shooting mode is turned on, the timer is turned on at the start of shooting, and it is judged whether the timer has reached the preset time, and the shooting is stopped when the timer counts up to the preset time.

A computer program comprising program instructions that, when executed by a computer, cause the computer to perform any of the above-described methods of star-tracking processing.

A carrier carrying the computer program as described.

A method and device for processing a star track of the technical solution of the present invention can determine the center of the star track of the current shooting only according to the star track arc of any star track arc when shooting the star track, and then The star-track arcs in the composite image extend around the center of the circle to obtain a complete star-track rendering, thus enabling the photographer to capture a complete star-track image in a shorter period of time. And when each segment of the star-track arc in the composite image is extended around the center of the circle, the star-track region and the non-star-track region in the composite image may be distinguished, and the arcs of each segment of the star track are extended only in the star-track region. The resulting star-track renderings are more in line with the actual shooting results.

BRIEF abstract

1 is a schematic block diagram of a camera device according to an embodiment of the present invention;

2 is a flowchart of a method for photographing according to an embodiment of the present invention;

Figure 3 is a flow chart of step S201 of Figure 2;

4 is a schematic diagram of an implementation method of step S201 in FIG. 2;

5 is a flow chart of a method 1 for identifying a star track area and a non-star track area in the composite image in the embodiment shown in FIG. 2;

6 is a flow chart of a second method for identifying a star track zone and a non-star track zone in the composite image in the embodiment shown in FIG. 2.

Preferred embodiment of the invention

The following is an overview of the topics detailed in this document. This Summary is not intended to limit the scope of the claims.

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Referring to FIG. 1 , an embodiment of the present invention provides a photographing apparatus. The photographing apparatus includes a detecting unit 101, a control unit 102, a center determining unit 103, and a processing unit 104.

In practical applications, after the start of the star track shooting, the camera collects an image every preset time; determines whether the brightness of the pixel in the current image at the same position is greater than the brightness of the pixel in the image obtained in the past; if so, the The pixels in the same position in the image are replaced with the pixels in the current image, and the synthesis of the star track image is performed accordingly. The star track in the complete star-track image is composed of multiple concentric circles around the same center.

The detecting unit 101 is configured to detect whether the fast shooting mode is turned on when entering the star track shooting mode.

The device further includes a setting unit (not shown), wherein the setting unit is configured to: determine whether to enable the fast shooting mode according to actual needs, and set the fast shooting mode by setting the quick shooting mode function entry to be turned on. filming time.

The control unit 102 is configured to: when the detecting unit 101 detects that the quick shooting mode is turned on, control the shooting device to end the star track shooting when the shooting is performed to a preset time.

Alternatively, the control unit 102 can implement control of the shooting time by a timer. At this time, the control unit 102 is further configured to: when the fast shooting mode is turned on, turn on the timer at the start of shooting, and determine whether the timing of the timer reaches a preset time, and set to: the timing of the timer is reached. Shooting stops at a preset time.

The center determining unit 103 is configured to: after the end of the star track shooting, calculate the center of the star track of the current shooting according to any of the star track arcs in the composite image.

Optionally, the method for determining, by the processing unit 104, the center of the star track of the current shooting according to the star track in the composite image is as shown in FIG. 4, and the details are as follows:

Extracting two points A and B on the arc of any one of the segments, calculating a midpoint C of the straight line a with the two points A and B as end points, and confirming through the midpoint C and perpendicular to the straight line a vertical line b, and is set to: determine an intersection D of the perpendicular line b and the arc of any one of the segments, and match the two points A and B with a circle whose center is located on the vertical line, and find Through the two points A and B and the circumference of the intersection D, and determining that the circumference is the trajectory of any of the segments of the star track, the center E of the circumference is the center of the star track of the current shooting.

The processing unit 104 is configured to: extend each segment of the star track arc in the center of the circle calculated by the calculating unit to obtain a complete star track rendering.

Optionally, the processing unit 104 extends the segment of the star track in the composite image to obtain a complete star track rendering image, and is further configured to: identify the star track region and the non-star track region in the composite image, and Each segment of the star track in the composite image is extended around the center of the star in the star track region.

In practical applications, the processing unit 104 can identify the star track zone and the non-star track zone by two methods.

method one,

Obtaining a range of brightness values of the pixels in the star track area, and scanning the pixels in the star track image row by row, obtaining brightness values of each pixel point, and determining whether the brightness value of each pixel point is in the Within the range of the brightness value, and configured to: determine that the pixel point is a pixel point of the star track area when it is determined that the size of the brightness value of each pixel point is within the brightness value range; otherwise, determining the Pixels are pixels of a non-star track area.

Method Two,

The processing unit 104 is further configured to: determine, by performing the following steps, a pixel point in the non-star-track region of the captured star-track image: A, obtain a range of brightness values of the pixel points of the star-track region; B, and the star track The pixel points in the image are scanned row by row to obtain the brightness value of each pixel point; C. According to the obtained brightness value of each pixel point, the mutation of the brightness value in each row of pixel points exceeds the first preset threshold value. a pixel; D, determining that the magnitude of the luminance value between adjacent abrupt pixel points of each row exceeds the number of pixels of the luminance value range and all pixel points between the adjacent abrupt pixel points Whether the percentage of the quantity is greater than a preset second threshold value, and if so, determining that the pixel point between the adjacent abrupt pixel points is a pixel point of the non-star-track area, otherwise determining the adjacent mutant image The pixel between the prime points is the pixel of the star track area.

For example, there are 100 pixels between pixels A1-A100, and the brightness value of 10 pixels (A5, A12, A15, ...) exceeds the brightness value range, the percentage is 10%, which is less than the second threshold, then A1 is judged. -A100 is the star track area;

There are 100 pixels between the pixels B1-B100, and the brightness value of 70 pixels exceeds the brightness value range, and the percentage is 70%. If the value is greater than the second threshold, it is judged that B1-B100 is a non-star track area.

When the step C is performed, the processing unit 104 is further configured to: according to the obtained brightness value of each pixel point, find a sudden pixel point in which the change of the brightness value in each row of pixels exceeds the first preset threshold. : C1, determining that the first pixel and the last pixel in each row are abrupt pixels, and performing step C2 from the first pixel; C2, sequentially calculating brightness between adjacent pixels An absolute value of the difference, and determining whether an absolute value of a luminance difference between the current pixel point and a subsequent adjacent pixel point exceeds a first preset threshold, and if yes, performing step C3; C3, sequentially calculating the current pixel point and The absolute value of the brightness difference of the subsequent pixel points, and determines whether the current pixel point is the last pixel point, and if so, stops the calculation, if otherwise, until another pixel point whose absolute value of the brightness difference is less than the first preset threshold value is found And determining whether the number of N pixel points spaced between the other pixel point and the current pixel point is greater than a third predetermined threshold, and if so, determining that the current pixel point and another pixel point are abrupt pixels And another pixel to pixel as a mutation execution continues in step C2.

For example, a row of pixels C1-C100, determine C1, C100 as abrupt pixel points,

Calculate the absolute value of the luminance difference between C1 and C2, the absolute value of the luminance difference between C2 and C3, and calculate whether the absolute value of the above luminance difference exceeds the first preset threshold, such as C11 and The absolute value of the difference in luminance between C12 exceeds the first preset threshold.

Calculate the absolute value of the luminance difference between C11 and C12, C11 and C13, C11 and C14... in order, and calculate whether the absolute value of the above luminance difference is smaller than the first preset threshold, for example, the absolute difference between the luminance difference between C11 and C36 The value is less than the first preset threshold, and the interval between C11 and C36 is 25 pixels, which is greater than the third preset threshold, and it is determined that C11 and C36 are abrupt pixel points.

Optionally, when the processing unit 104 extends the star track in the composite image around the center of the star track, it may extend from one end of the arc or simultaneously from both ends of the arc. Extend; you can also copy the arc of the segment of the star track first, and then repeatedly paste the arc on the circumference of the segment of the star track to make it more realistic.

In practical applications, the processing unit 104 may also scan the pixels in the star track image row by row and read the brightness values of the pixels with the same distance. The first preset threshold, the second preset threshold, and the range of brightness values of the satellite track pixels can be obtained based on experimental data. The range of brightness values of the pixels in the star track area can also be obtained by statistically counting the brightness values of the pixels in the first row of the star track image during scanning.

In practical applications, the device can also set a display unit, which is set to: display a complete star track rendering.

The photographing device of the embodiment can turn on the fast shooting mode when performing the star track shooting, and when the fast shooting mode is turned on, the shooting can be stopped only by shooting the preset time, and then the composite image when the shooting is stopped is acquired. Determining the center of the star track of the current shooting according to the star track arc in the composite image, and then extending the arc of each star track in the composite image around the center of the circle to obtain a complete star track rendering image, thereby enabling The photographer takes a complete star track image in a short period of time. And when each segment of the star-track arc in the composite image is extended around the center of the circle, the star-track region and the non-star-track region in the composite image may be distinguished, and the arcs of each segment of the star track are extended only in the star-track region. The resulting star-track renderings are more in line with the actual shooting results.

On the basis of the foregoing device embodiments, an embodiment of the present invention provides a shooting method. Referring to FIG. 2, the method process includes:

S201. After the star track is finished, the center of the star track of the current shooting is calculated according to any segment of the star track in the composite image.

Please refer to FIG. 3 and FIG. 4, the steps include:

S2011, extracting two points A and B on the arc of any one of the star tracks;

S2012, calculating a midpoint C of the straight line a with the two points A and B as the end points, and confirming the perpendicular line b passing through the midpoint C and perpendicular to the straight line;

S2013, determining an intersection D of the perpendicular line b and the arc of any one of the segments;

S2014, matching the two points A and B with the circumference of the center line on the vertical line, and searching for The two points A and B and the circumference of the intersection point D, and determine that the circumference is the trajectory of the arc of any of the segments, the center E of the circumference is the center of the star track of the current shot.

S202. Extend each segment of the star track arc in the composite image around the center of the circle to obtain a complete star track rendering.

When performing this step, the star track area and the non-star track area in the composite image may also be identified; and each segment of the star track in the composite image is extended around the center of the star track area.

Alternatively, identifying the star-track region and the non-star-track region in the composite image can be implemented in two ways.

Referring to Figure 5, method one includes:

S401. Acquire a range of brightness values of pixels in the star track area;

S402. Perform a row-by-row scan on the pixel points in the image of the star track to obtain a brightness value of each pixel point.

S403. Determine whether a size of the brightness value of each pixel is within the brightness value range.

S405. If yes, determine that the pixel point is a pixel point of the star track area, otherwise, determine that the pixel point is a pixel point of the non-star track area.

Please refer to Figure 6. Method 2 includes:

A. Obtain a range of brightness values of pixels in the star track area;

B. scanning the pixels in the star track image row by row to obtain the brightness value of each pixel point;

D. determining whether the brightness value between adjacent abrupt pixel points of each row exceeds the range of the pixel value of the brightness value range and the percentage of the number of all pixel points between the adjacent abrupt pixel points is greater than a preset second threshold value, if yes, determining that the pixel point between the adjacent abrupt pixel points is a pixel point of the non-satellite track area, otherwise determining that the pixel point between the adjacent abrupt pixel points is a star track area Pixels.

There are 100 pixels between pixels B1-B100, and 70 of them have brightness values exceeding The brightness value range, the percentage is 70%, and is greater than the second threshold, then it is determined that B1-B100 is a non-satellite track area.

In practical applications, the implementation method of step C includes the following steps C1-C3.

In an actual application, before performing step S201, the embodiment may further include the following steps:

S1. When entering the star track shooting mode, it is detected whether the fast shooting mode is turned on.

Optionally, the fast shooting mode function entry can be turned on by setting, and the user determines whether to enable the fast shooting mode according to actual needs, and set the shooting time of the fast shooting mode.

S2. If the quick shooting mode is turned on, shooting stops when the shooting progresses to the preset time.

Optionally, the step includes:

Determining whether the timing of the timer reaches a preset time;

Shooting stops if the preset time is reached.

S3. Acquire a current composite image.

It should be noted that when the related art utilizes a digital camera (especially a mobile terminal) to take a star track, multiple images are taken in a long time multiple exposure mode, and the current captured image and the previous image are taken during the shooting process. The synthesis process is performed so that when the shooting is completed, the synthesized star track image can be directly obtained. Therefore, when the shooting is stopped in this embodiment, the current composite image is acquired as the image after the last image captured and the previous image (ie, the previous composite image).

In the shooting method of the embodiment, the fast shooting mode can be turned on when the star track is taken, and when the fast shooting mode is turned on, the shooting can be stopped only by shooting the preset time, and then the composite image when the shooting is stopped is acquired. Determining the center of the star track of the current shooting according to the star track arc in the composite image, and then extending the arc of each star track in the composite image around the center of the circle to obtain a complete star track rendering image, thereby enabling The photographer takes a complete star track image in a short period of time. And when each segment of the star-track arc in the composite image is extended around the center of the circle, the star-track region and the non-star-track region in the composite image may be distinguished, and the arcs of each segment of the star track are extended only in the star-track region. The resulting star-track renderings are more in line with the actual shooting results.

The embodiment of the invention also discloses a computer program, comprising program instructions, which when executed by a computer, enable the computer to execute any of the above-mentioned star track shooting processing methods.

The embodiment of the invention also discloses a carrier carrying the computer program.

Other aspects will be apparent upon reading and understanding the drawings and detailed description.

The preferred embodiments of the present invention have been described above with reference to the drawings, and are not intended to limit the scope of the invention. Any modifications, equivalent substitutions and improvements made by those skilled in the art without departing from the scope and spirit of the invention are intended to be included within the scope of the invention.

Industrial applicability

A method and device for processing a star track of the technical solution of the present invention can determine the center of the star track of the current shooting only according to the star track arc of any star track arc when shooting the star track, and then The star-track arcs in the composite image extend around the center of the circle to obtain a complete star-track rendering, thus enabling the photographer to capture a complete star-track image in a shorter period of time. And when each segment of the star-track arc in the composite image is extended around the center of the circle, the star-track region and the non-star-track region in the composite image may be distinguished, and the arcs of each segment of the star track are extended only in the star-track region. The resulting star-track renderings are more in line with the actual shooting results. Therefore, the present invention has strong industrial applicability.

Claims

A method for processing a star track photograph, comprising the following steps:

After the star track is finished, the center of the star track of the current shooting is calculated according to any segment of the star track in the composite image;

Extending each segment of the star-track arc in the composite image around the center of the circle to obtain a complete star-track rendering.
The method of processing a star-tracking method according to claim 1, wherein, after the star-tracking is completed, the step of calculating a center of the star-track of the current shooting according to any one of the star-track arcs in the composite image comprises:

Extracting two points on the arc of any of the segments of the star;

Calculating a midpoint of a straight line ending at the two points, and confirming a perpendicular line passing through the midpoint and perpendicular to the straight line;

Determining an intersection of the perpendicular to the arc of any of the segments;

Matching the two points with a circumference on which the center of the circle is located, finding a circle passing through the two points and the intersection, and determining that the circumference is a trajectory of any of the segments of the star track, The center of the circle is the center of the star track for this shot.
The method for processing a star-tracking method according to claim 1 or 2, wherein the step of extending each segment of the star-track arc in the composite image around the center of the circle to obtain a complete star-track effect map comprises:

Identifying a star track zone and a non-star track zone in the composite image;

Each segment of the star track in the composite image is extended around the center of the star in the star track region.
The satellite track photographing processing method according to claim 3, wherein said step of identifying a star track area and a non-star track area in said composite image comprises:

Obtain a range of luminance values of pixels in the star track area;

Performing a row-by-row scan on the pixel points in the star-track image to obtain a brightness value of each pixel point;

Determining whether the magnitude of the luminance value of each pixel is within the range of the luminance value;

If yes, it is determined that the pixel point is a pixel point of the star track area, otherwise, the pixel point is determined to be a pixel point of the non-star track area.
The satellite track photographing processing method according to claim 3, wherein said step of identifying a star track area and a non-star track area in said composite image comprises:

A. Obtain a range of brightness values of pixels in the star track area;

B. Scan the pixels in the star track image row by row to obtain the brightness value of each pixel point;

C. Find, according to the obtained brightness value of each pixel point, a sudden pixel point in which the change of the brightness value in each row of pixels exceeds the first preset threshold;

D. determining that the size of the luminance value between adjacent abrupt pixel points of each row exceeds the number of pixels of the luminance value range and the percentage of the number of all pixel points between the adjacent abrupt pixel points Whether it is greater than a preset second threshold, if yes, determining that a pixel point between the adjacent abrupt pixel points is a pixel point of a non-star-track region, otherwise determining a pixel point between the adjacent abrupt pixel points The pixel point of the star track area.
The method of processing a star-tracking method according to claim 5, wherein said C step comprises:

C1, determining that the first pixel and the last pixel in each row are abrupt pixels, and performing step C2 from the first pixel;

C2, sequentially calculating an absolute value of a luminance difference between adjacent pixel points, and determining whether an absolute value of a luminance difference between the current pixel point and a subsequent adjacent pixel point exceeds a first preset threshold, and if so, Perform step C3;

C3. Calculate the absolute value of the brightness difference between the current pixel point and the subsequent pixel point in turn, and determine whether the current pixel point is the last pixel point, and if so, stop the calculation, if otherwise, until the absolute value of the brightness difference is less than the first Presetting another pixel point of the threshold, and determining whether the number of N pixel points spaced between the other pixel point and the current pixel point is greater than a third predetermined threshold, and if so, determining the The current pixel point and the other pixel point are abrupt pixel points, and step C2 is continued with another pixel point as the abrupt pixel point.
The method of processing a star-tracking method according to claim 1, wherein after the step of shooting the star track, the step of calculating the center of the star track of the current shooting according to any of the star-track arcs in the composite image, the method further comprises:

S1, when entering the star track shooting mode, detecting whether the fast shooting mode is turned on;

S2. If the fast shooting mode is turned on, the shooting is stopped when the shooting is performed to a preset time;

S3. Acquire a current composite image.
The method of processing a star-tracking process according to claim 7, wherein said step S1 comprises:

By setting the function of the quick shooting mode to be turned on, the user determines whether to enable the quick shooting mode and set the shooting time of the fast shooting mode according to actual needs.
The method of claim 7, wherein the step S2 comprises:

If the quick shooting mode is turned on, the timer is turned on at the beginning of shooting;

Determining whether the timing of the timer reaches a preset time;

Shooting stops if the preset time is reached.
A photographing apparatus comprising a center determining unit and a processing unit, wherein:

The center determining unit is configured to: after the end of the star track shooting, calculate the center of the star track of the current shooting according to any segment of the star track in the composite image;

The processing unit is configured to: extend each segment of the star track arc in the center of the circle calculated by the calculating unit to obtain a complete star track rendering.
The photographing apparatus according to claim 10, wherein the center determining unit is set to Calculate the center of the star track of this shot based on any of the star-track arcs in the composite image as follows:

Extracting two points on the arc of any of the segments of the star;

Calculating a midpoint of a straight line ending at the two points, and confirming a perpendicular line passing through the midpoint and perpendicular to the straight line;

Determining an intersection of the perpendicular to the arc of any of the segments;

Matching the two points with a circumference on which the center of the circle is located, finding a circle passing through the two points and the intersection, and determining that the circumference is a trajectory of any of the segments of the star track, The center of the circle is the center of the star track for this shot.
The photographing apparatus according to claim 10 or 11, wherein the processing unit is configured to extend each segment of the star-track arc in the composite image around the center of the circle to obtain a complete star-track effect map as follows:

Identifying a star track zone and a non-star track zone in the composite image;

Each segment of the star track in the composite image is extended around the center of the star in the star track region.
The photographing apparatus according to claim 12, wherein said processing unit is configured to identify a star track area and a non-star track area in said composite image as follows:

Obtain a range of luminance values of pixels in the star track area;

Performing a row-by-row scan on the pixel points in the star-track image to obtain a brightness value of each pixel point;

Determining whether the magnitude of the luminance value of each pixel is within the range of the luminance value;

When it is determined that the size of the brightness value of each pixel is within the range of the brightness value, determining that the pixel point is a pixel point of the star track area, otherwise, determining that the pixel point is a pixel point of the non-star track area .
The photographing apparatus according to claim 12, wherein said processing unit is configured to identify a star track area and a non-star track area in said composite image as follows:

A. Obtain a range of brightness values of pixels in the star track area;

B. Scan the pixels in the star track image row by row to obtain the brightness value of each pixel point;

C. Find, according to the obtained brightness value of each pixel point, a sudden pixel point in which the change of the brightness value in each row of pixels exceeds the first preset threshold;

D. determining that the size of the luminance value between adjacent abrupt pixel points of each row exceeds the number of pixels of the luminance value range and the percentage of the number of all pixel points between the adjacent abrupt pixel points Whether it is greater than a preset second threshold, if yes, determining that a pixel point between the adjacent abrupt pixel points is a pixel point of a non-star-track region, otherwise determining a pixel point between the adjacent abrupt pixel points The pixel point of the star track area.
The photographing apparatus according to claim 14, wherein the processing unit is configured to search for the change of the brightness value in each row of pixels beyond the first preset threshold according to the acquired brightness values of the respective pixel points as follows. Mutated pixel points:

C1, determining that the first pixel and the last pixel in each row are abrupt pixels, and performing step C2 from the first pixel;

C2, sequentially calculating an absolute value of a luminance difference between adjacent pixel points, and determining whether an absolute value of a luminance difference between the current pixel point and a subsequent adjacent pixel point exceeds a first preset threshold, and if so, Perform step C3;

C3. Calculate the absolute value of the brightness difference between the current pixel point and the subsequent pixel point in turn, and determine whether the current pixel point is the last pixel point, and if so, stop the calculation, if otherwise, until the absolute value of the brightness difference is less than the first Presetting another pixel point of the threshold, and determining whether the number of N pixel points spaced between the other pixel point and the current pixel point is greater than a third predetermined threshold, and if so, determining the current pixel point and another pixel The point is the abrupt pixel point, and step C2 is continued with another pixel point as the abrupt pixel point.
The photographing apparatus according to claim 10, further comprising a detecting unit and a control unit, wherein

The detecting unit is configured to detect whether to enable fast shooting when entering the star track shooting mode mode;

The control unit is configured to: when the detecting unit detects that the quick shooting mode is turned on, control the shooting device to end the star track shooting when the shooting is performed to a preset time.
The photographing apparatus according to claim 16, further comprising a setting unit, wherein

The setting unit is configured to: determine whether to enable the fast shooting mode according to actual needs, and set the shooting time of the fast shooting mode by setting the function button of the fast shooting mode to be turned on.
The photographing apparatus according to claim 16, wherein the control unit is configured to control the photographing device to end the star track when the photographing is performed to a preset time when the detecting unit detects that the quick shooting mode is turned on as follows Shooting:

When the quick shooting mode is turned on, the timer is turned on at the start of shooting, and it is judged whether the timer has reached the preset time, and the shooting is stopped when the timer counts up to the preset time.
A computer program comprising program instructions which, when executed by a computer, cause the computer to perform the star-tracking processing method of any one of claims 1-9.
A carrier carrying the computer program of claim 19.