WO2016155124A1 - Method and device for removing singular point noise - Google Patents

Abstract

Disclosed are a method and device for removing singular point noise. For various pixel points in an image to be sent to an encoder, the following process is executed: calculating a luminance difference value and a chrominance difference value between every two pixel points in several neighbouring pixel points of a current pixel point, so as to obtain several first luminance difference values and several first chrominance difference values; calculating a luminance difference value and a chrominance difference value between the current pixel point and various neighbouring pixel points, so as to obtain several second luminance difference values and several second chrominance difference values; when it is judged that an absolute value of each of the first luminance difference values is less than a first pre-set luminance threshold value, and an absolute value of a second luminance difference value with the minimum absolute value in the various second luminance difference values is greater than a second pre-set luminance threshold value, setting a luminance value of the current pixel point to be an average value of luminance values of the various neighbouring pixel points; and as for the chrominance of the pixel points, performing execution according to the luminance processing method. By means of the process, singular point noise in an image is removed, and the user experience is improved.

Description

Method and device for removing singular noise Technical field

This application claims the priority of the domestic application filed on March 30, 2015, the Chinese Patent Office, Application No. 201510145620.9, entitled "A Method and Apparatus for Removing Singular Noise", the entire contents of which are incorporated herein by reference. In the application.

Background technique

In the self-media technology, network video applications are emerging one after another. The main process of network video is to collect image information by the camera and send the image information to the encoder, and the image information is encoded by the encoder for display by the terminal.

Because the cameras on the market vary widely and the quality is uneven, the image information collected by the camera and sent to the encoder has a lot of noise, also known as singularity. These singular noises are amplified by the encoder and seriously affect the user experience.

Summary of the invention

In view of this, the present application provides a method and apparatus for removing singular noise, which is used to solve the problem that affects the user experience caused by the image information collected by the camera including singular noise.

In order to achieve the above objectives, the proposed scheme is as follows:

A method of removing singular noise that performs the following process for each pixel in an image to be sent to an encoder:

Calculating a luminance difference value and a chrominance difference value of two or two pixel points of the plurality of neighboring pixel points of the current pixel point, obtaining a plurality of first luminance difference values and a plurality of first chrominance difference values; calculating the current pixel point and each of the foregoing a luminance difference value and a chrominance difference value of neighboring pixels, to obtain a plurality of second luminance difference values and a plurality of second chrominance difference values;

Determining whether an absolute value of each of the first brightness difference values is less than a first preset brightness threshold;

If yes, determining whether an absolute value of the second brightness difference value whose absolute value is the smallest among the second brightness difference values is greater than a second preset brightness threshold value;

If yes, setting a brightness value of the current pixel point to an average value of brightness values of each of the neighboring pixel points;

Determining whether an absolute value of each of the first chromaticity difference values is less than a first preset chromaticity threshold;

If yes, determining whether an absolute value of the second chromaticity difference value whose absolute value is the smallest among the second chromaticity difference values is greater than a second preset chromaticity threshold value;

If so, the chrominance value of the current pixel point is set to an average value of the chrominance values of each of the neighboring pixel points.

Preferably, when the image is an image of the YUV format, the calculated first luminance difference is ΔY1, the first chrominance difference is ΔU1 and ΔV1, and the second luminance difference is ΔY2, second. The chromaticity difference values are ΔU2 and ΔV2, the first preset chromaticity threshold includes a first preset U value and a first preset V value, and the second preset chromaticity threshold includes a second pre- Setting a U value and a second preset V value;

Determining whether an absolute value of each of the first chromaticity difference values is smaller than a first preset chromaticity threshold value, and determining a minimum value of each of the second chromaticity difference values when the determination result is YES The process of whether the absolute value of the dichromatic difference value is greater than the second preset chroma threshold is:

Determining whether the absolute value of each ΔU1 is smaller than the first preset U value;

When it is determined that the absolute value of each ΔU1 is less than the first preset U value, it is determined whether the absolute value of ΔU2 with the smallest absolute value in each ΔU2 is greater than the second preset U value;

Determining whether the absolute value of each ΔV1 is less than a first preset V value;

When it is determined that the absolute value of each ΔV1 is smaller than the first preset V value, it is determined whether the absolute value of ΔV2 whose absolute value is the smallest among the ΔV2 is greater than the second preset V value.

Preferably, the setting a chromaticity value of the current pixel point as an average value of chrominance values of each of the neighboring pixel points includes:

When it is determined that the absolute value of each ΔU1 is smaller than the first preset U value, and the absolute value of ΔU2 whose absolute value is the smallest among the ΔU2 is determined to be greater than the second preset U value, the chromaticity of the current pixel point will be determined. a value set to an average of chrominance values for each of the neighboring pixel points; and,

When it is determined that the absolute value of each ΔV1 is smaller than the first preset V value, and it is determined that the absolute value of ΔV2 whose absolute value is the smallest among the ΔV2 is greater than the second preset V value, the chromaticity of the current pixel point will be The value is set to the average of the chrominance values of each of the neighboring pixel points.

Preferably, the plurality of neighboring pixel points of the current pixel point are:

Four pixels above, below, to the left, and to the right of the current pixel.

A device for removing singular noise, for each pixel in an image to be sent to an encoder Point processing, the device includes:

a first calculating unit, configured to calculate a luminance difference value and a chrominance difference value of two or two pixel points of the plurality of neighboring pixel points of the current pixel point, to obtain a plurality of first brightness difference values and a plurality of first chromaticity difference values;

a second calculating unit, configured to calculate a luminance difference value and a chrominance difference value between the current pixel point and each of the neighboring pixel points, to obtain a plurality of second brightness difference values and a plurality of second chromaticity difference values;

a first determining unit, configured to determine whether an absolute value of each of the first brightness difference values is smaller than a first preset brightness threshold;

a second determining unit, configured to determine, when the first determining unit determines that the value is YES, whether the absolute value of the second brightness difference value whose absolute value is the smallest among the second brightness difference values is greater than the second preset brightness threshold ;

a pixel brightness processing unit, configured to set a brightness value of the current pixel point to an average value of brightness values of each of the neighboring pixel points when the second determining unit determines to be YES;

a third determining unit, configured to determine whether an absolute value of each of the first chrominance differences is less than a first preset chromaticity threshold;

a fourth determining unit, configured to determine, when the third determining unit determines that the value is YES, whether the absolute value of the second chromaticity difference value whose absolute value is the smallest among the second chromaticity difference values is greater than the second preset color Degree threshold

And a pixel chrominance processing unit configured to set a chromaticity value of the current pixel point to an average value of chromaticity values of each of the neighboring pixel points when the fourth determining unit determines that the value is YES.

Preferably, when the image is an image of the YUV format, the calculated first luminance difference is ΔY1, the first chrominance difference is ΔU1 and ΔV1, and the second luminance difference is ΔY2, second. The chromaticity difference values are ΔU2 and ΔV2, the first preset chromaticity threshold includes a first preset U value and a first preset V value, and the second preset chromaticity threshold includes a second pre- Setting a U value and a second preset V value;

The third determining unit includes:

a first U value determining unit, configured to determine whether an absolute value of each ΔU1 is smaller than a first preset U value;

a first V value determining unit, configured to determine whether an absolute value of each ΔV1 is smaller than a first preset V value;

The fourth determining unit includes:

The second U value determining unit is configured to determine, when the first U value determining unit determines that the absolute value of each ΔU1 is smaller than the first preset U value, whether the absolute value of the ΔU2 having the smallest absolute value in each ΔU2 is large At a second preset U value;

The second V value determining unit is configured to determine, when the first V value determining unit determines that the absolute value of each ΔV1 is smaller than the first preset V value, whether the absolute value of the ΔV2 having the smallest absolute value in each ΔV2 is greater than The second preset V value.

Preferably, the pixel chrominance processing unit comprises:

a pixel chrominance processing sub-unit, configured to determine that an absolute value of each ΔU1 is smaller than a first preset U value, and determine that an absolute value of ΔU2 having the smallest absolute value in each ΔU2 is greater than a second preset U value, Setting a chromaticity value of the current pixel point to an average value of chrominance values of each of the neighboring pixel points; and determining that an absolute value of each ΔV1 is smaller than a first preset V value, and determining each ΔV2 When the absolute value of ΔV2 with the smallest absolute value is greater than the second preset V value, the chrominance value of the current pixel point is set to the average value of the chrominance values of each of the neighboring pixel points.

Preferably, the plurality of neighboring pixel points of the current pixel point are:

Four pixels above, below, to the left, and to the right of the current pixel.

It can be seen from the above technical solution that the method for removing singular noise provided by the embodiment of the present application performs the following process for each pixel in an image to be sent to the encoder: calculating several neighbor pixels of the current pixel a luminance difference value and a chrominance difference value of two or two pixels in the point, to obtain a plurality of first luminance difference values and a plurality of first chrominance difference values; calculating luminance difference values and colors of the current pixel point and each of the neighboring pixel points a difference value, a plurality of second brightness difference values and a plurality of second color difference values are obtained; determining that an absolute value of each of the first brightness difference values is smaller than a first preset brightness threshold, and each of the second brightness differences When the absolute value of the second brightness difference value whose absolute value is the smallest value is greater than the second preset brightness threshold value, the brightness value of the current pixel point is set as the average value of the brightness values of each of the neighboring pixel points; The absolute value of each of the first chromaticity differences is smaller than the first preset chromaticity threshold, and the absolute value of the second chromaticity difference having the smallest absolute value among the second chromaticity differences is greater than the second pre- The current pixel point when the chroma threshold is set Chrominance value to the average chroma value of each of the neighboring pixels. Through the above process, the singular noise in the image is removed, and the user's experience is improved.

DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will be The drawings used in the embodiments or the description of the prior art are briefly introduced. It is obvious that the drawings in the following description are merely examples of the present application, and no one skilled in the art will be engaged in creative labor. Further drawings may also be obtained from the drawings provided.

FIG. 1 is a flowchart of a method for removing singular noise according to an embodiment of the present application;

2 is a bitmap of an 8*8 pixel according to an example of an embodiment of the present application;

FIG. 3 is a schematic structural diagram of an apparatus for removing singular noise according to an embodiment of the present application.

detailed description

The technical solutions in the embodiments of the present application are clearly and completely described in the following with reference to the drawings in the embodiments of the present application. It is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present application without departing from the inventive scope are the scope of the present application.

The embodiment of the present application provides a method for removing singular noise, which is processed for each pixel in an image to be sent to an encoder, and the specific processing process is shown in FIG. 1 .

Before introducing the solution of the present application, it should be explained that the pixel of the image is composed of two factors of brightness and chrominance, and the value of either one of the two is too high or too low, which may cause the pixel to become a singular noise.

As shown in Figure 1, the method includes:

Step S100: Calculate a luminance difference value and a chrominance difference value of two or two pixel points of the plurality of neighboring pixel points of the current pixel point, to obtain a plurality of first brightness difference values and a plurality of first color difference values;

Specifically, the pixels in the image are generally arranged in a rectangle, and each pixel has a neighbor pixel. It can be understood that the number of neighboring pixel points of the pixel points on the four sides of the image is smaller than the number of neighboring pixel points of the pixel points in the middle of the image.

In this step, the luminance difference and the chrominance difference between the two pairs are calculated for a plurality of neighboring pixel points of the current pixel.

Step S110, calculating a luminance difference value and a chrominance difference value between the current pixel point and each of the neighboring pixel points, to obtain a plurality of second brightness difference values and a plurality of second chromaticity difference values;

Step S120, determining whether the absolute value of each of the first brightness difference is less than the first preset brightness threshold; if yes, executing step S130;

The first preset brightness threshold value is a preset value. If the absolute values of the respective first brightness difference values are smaller than the value, it means that the brightness difference of the neighboring pixel points is not large, and there is no singular point noise.

Step S130, determining whether the absolute value of the second brightness difference value with the smallest absolute value among the second brightness difference values is greater than the second preset brightness threshold; if yes, executing step S140;

Wherein, the second preset brightness threshold value is a preset value, and if the absolute value of the second brightness difference value which is the smallest of the second brightness difference values is greater than the value, it means that the brightness of the current pixel point is far Far greater than the brightness of its neighboring pixels. Moreover, since it has been determined that the neighboring pixel points of the current pixel point are non-singular point noise, it can be determined that the current pixel point is a singular point noise.

Step S140, setting a brightness value of the current pixel point as an average value of brightness values of each of the neighboring pixel points;

After determining that the current pixel point is a singular noise in the previous step, it is necessary to adjust the brightness value of the current pixel point. During the specific adjustment, the brightness value of the current pixel point is adjusted to the average value of the luminance values of its neighboring pixel points.

Step S150, determining whether the absolute value of each of the first chromaticity difference is less than the first preset chromaticity threshold; if yes, executing step S160;

The first preset chroma threshold is a preset value. If the absolute values of the first chroma differences are smaller than the value, it means that the chroma of the neighbor pixels is not much different, and there is no oddity. Point noise.

Step S160, determining whether the absolute value of the second chromaticity difference value whose absolute value is the smallest among the second chromaticity difference values is greater than the second preset chromaticity threshold value; if yes, executing step S170;

Wherein, the second preset chroma threshold is a preset value, and if the absolute value of the second chroma difference of the smallest of the second chroma differences is greater than the value, the current pixel is The chromaticity is much larger than the chrominance of its neighboring pixels. Moreover, since it has been determined that the neighboring pixel points of the current pixel point are non-singular point noise, it can be determined that the current pixel point is a singular point noise.

Step S170: Set a chromaticity value of the current pixel point as an average value of chrominance values of each of the neighboring pixel points.

After determining that the current pixel is a singular noise in the previous step, it is necessary to adjust the chrominance value of the current pixel. When the adjustment is made, the chromaticity value of the current pixel is adjusted to its neighbor pixel color. The average of the degrees.

It should be noted that the foregoing steps S100 and S110 do not limit the sequence, and steps S120-S140 and steps S150-S170 are two independent determination processes, which may be performed separately or sequentially. Just illustrate the case where these two links are executed independently.

The method for removing singularity noise provided by the embodiment of the present application performs the following process for calculating each pixel point in an image to be sent to the encoder: calculating brightness of two or two pixel points among several neighboring pixel points of the current pixel point And a difference between the difference and the chrominance, obtaining a plurality of first luminance differences and a plurality of first chrominance differences; calculating a luminance difference and a chrominance difference between the current pixel and each of the neighboring pixels to obtain a plurality of second luminances a difference value and a plurality of second chromaticity difference values; determining that the absolute value of each of the first brightness difference values is smaller than a first preset brightness threshold, and wherein the second brightness of each of the second brightness difference values is the smallest When the absolute value of the difference is greater than the second preset brightness threshold, setting the brightness value of the current pixel point to an average value of the brightness values of each of the neighboring pixel points; determining each of the first chromaticity difference values The absolute value of the second chromaticity difference value is smaller than the second preset chromaticity threshold, and the absolute value of the second chromaticity difference value of each of the second chromaticity difference values is greater than the second preset chromaticity threshold The chrominance value of the current pixel is set to each of the neighbor images Point average chroma values. Through the above process, the singular noise in the image is removed, and the user's experience is improved.

It should be noted that the neighboring pixel points of the current pixel point described above can be understood as four pixel points above, below, to the left, and to the right of the current pixel point. Of course, if the current pixel is at the edge of the image, the neighboring pixels of the pixel may be less than four, and only the remaining neighbor pixels need to be considered.

Since the existing encoder can only encode image information in the YUV format, if the image captured by the camera is image information in the RGB format, it is necessary to convert the image information into the YUV format according to the existing formula. The image in the YUV format includes a luminance signal Y and two chrominance signals U and V.

For the image in which the image is in the YUV format, we introduce the scheme of the above embodiment.

First, the first luminance difference obtained by the above calculation is ΔY1, the first chromaticity difference is ΔU1 and ΔV1, the second luminance difference is ΔY2, and the second chromaticity difference is ΔU2 and ΔV2. The first preset chroma threshold includes a first preset U value and a first preset V value, and the second preset chroma threshold includes a second preset U value and a second preset V value.

1. The above process of determining whether the absolute value of each of the first brightness difference values is less than the first preset brightness threshold is:

It is determined whether the absolute value of each ΔY1 is smaller than the first preset brightness threshold.

2. The process of determining whether the absolute value of the second brightness difference value with the smallest absolute value among the second brightness difference values is greater than the second preset brightness threshold is:

It is judged whether or not the absolute value of ΔY2 whose absolute value is the smallest among the respective ΔY2 is greater than the second preset brightness threshold.

3. determining whether the absolute value of each of the first chromaticity differences is smaller than a first preset chromaticity threshold, and determining that the absolute value of each of the second chromaticity differences is the smallest when the determination result is YES. The process of whether the absolute value of the second chromaticity difference is greater than the second preset chromaticity threshold is:

Determining whether the absolute value of each ΔU1 is smaller than the first preset U value;

When it is determined that the absolute value of each ΔU1 is smaller than the first preset U value, it is determined whether the absolute value of ΔU2 whose absolute value is the smallest among the ΔU2 is greater than the second preset U value.

as well as,

Determining whether the absolute value of each ΔV1 is less than a first preset V value;

When it is determined that the absolute value of each ΔV1 is smaller than the first preset V value, it is determined whether the absolute value of ΔV2 whose absolute value is the smallest among the ΔV2 is greater than the second preset V value.

4. The process of setting the chrominance value of the current pixel point to the average value of the chrominance values of each of the neighboring pixel points is as follows:

When it is determined that the absolute value of each ΔU1 is smaller than the first preset U value, and the absolute value of ΔU2 whose absolute value is the smallest among the ΔU2 is determined to be greater than the second preset U value, the chromaticity of the current pixel point will be determined. a value set to an average of chrominance values for each of the neighboring pixel points; and,

When it is determined that the absolute value of each ΔV1 is smaller than the first preset V value, and it is determined that the absolute value of ΔV2 whose absolute value is the smallest among the ΔV2 is greater than the second preset V value, the chromaticity of the current pixel point will be The value is set to the average of the chrominance values of each of the neighboring pixel points.

In summary, the luminance Y, the chrominance U, and the chrominance V of the pixel affect the singularity of the pixel. If the pixel point becomes singular noise due to the brightness Y, it is necessary to adjust the brightness Y of the pixel point; if the pixel point becomes singular noise due to the chromaticity U, it is necessary to adjust the chromaticity U of the pixel point; If the pixel point becomes singular noise due to the chromaticity V, it is necessary to adjust the chromaticity V of the pixel.

For ease of understanding, the embodiment is illustrated by a specific example, as shown in FIG. 2.

Figure 2 illustrates an 8*8 pixel lattice. The neighboring pixels of the pixel point P are selected as the upper, lower, left, and right pixel points of P (points marked with diagonal lines in the figure), and are defined as P _up , P _down , P _left , and P _{right, respectively} . In the present embodiment, only the process of judging whether or not the pixel point is singular noise by the brightness of the pixel point is exemplified. P is assumed luminance is 10, _the P, _the P, P _left, P _right 2,3,4,3 luminance respectively. The first preset brightness threshold is defined as 3, and the second preset brightness threshold is 5.

Since _{the upper} P, _the P, between P _{left, and right} points P, the difference between any two points of brightness are more than 3, and the point _P and P, _the P, P _{left, and right} points P The smallest difference among the luminance differences is 10-4=6, and since 6 is greater than the second preset luminance threshold 5, it is determined that the pixel point P is singular noise.

The apparatus for removing singular noise provided by the embodiment of the present application is described below, and the apparatus for removing singular noise described below and the method for removing singular noise described above may be referred to each other.

Referring to FIG. 3, FIG. 3 is a schematic structural diagram of an apparatus for removing singular noise according to an embodiment of the present application.

The device processes the individual pixels in the image to be sent to the encoder. As shown in Figure 3, the device comprises:

The first calculating unit 31 is configured to calculate a luminance difference value and a chrominance difference value of two or two pixel points of the plurality of neighboring pixel points of the current pixel point, to obtain a plurality of first brightness difference values and a plurality of first chromaticity difference values;

a second calculating unit 32, configured to calculate a luminance difference value and a chrominance difference value between the current pixel point and each of the neighboring pixel points, to obtain a plurality of second brightness difference values and a plurality of second color difference values;

The first determining unit 33 is configured to determine whether an absolute value of each of the first brightness difference values is smaller than a first preset brightness threshold;

The second determining unit 34 is configured to determine, when the first determining unit 33 determines that the value is YES, whether the absolute value of the second brightness difference value whose absolute value is the smallest among the second brightness difference values is greater than the second preset brightness Threshold

a pixel brightness processing unit 35, configured to set a brightness value of the current pixel point to an average value of brightness values of each of the neighboring pixel points when the second determining unit 34 determines YES;

The third determining unit 36 is configured to determine whether an absolute value of each of the first chromaticity difference values is smaller than a first preset chromaticity threshold value;

The fourth determining unit 37 is configured to determine, when the third determining unit 36 determines that the value is YES, whether the absolute value of the second chromaticity difference value whose absolute value is the smallest among the second chromaticity difference values is greater than the second pre-predetermined Set the chroma threshold;

The pixel chrominance processing unit 38 is configured to set a chromaticity value of the current pixel point to an average value of chromaticity values of each of the neighboring pixel points when the fourth determining unit 37 determines YES.

Optionally, when the image is an image of the YUV format, the calculated first brightness difference is ΔY1, the first chromaticity difference is ΔU1 and ΔV1, and the second brightness difference is ΔY2. The two chromaticity difference values are ΔU2 and ΔV2, the first preset chromaticity threshold includes a first preset U value and a first preset V value, and the second preset chromaticity threshold includes a second Presetting a U value and a second preset V value;

The third determining unit 36 may include:

a first U value determining unit, configured to determine whether an absolute value of each ΔU1 is smaller than a first preset U value;

a first V value determining unit, configured to determine whether an absolute value of each ΔV1 is smaller than a first preset V value;

The fourth determining unit includes:

The second U value determining unit is configured to determine, when the first U value determining unit determines that the absolute value of each ΔU1 is smaller than the first preset U value, whether the absolute value of the ΔU2 having the smallest absolute value in each ΔU2 is greater than a second preset U value;

The second V value determining unit is configured to determine, when the first V value determining unit determines that the absolute value of each ΔV1 is smaller than the first preset V value, whether the absolute value of the ΔV2 having the smallest absolute value in each ΔV2 is greater than The second preset V value.

The pixel chrominance processing unit 38 may include:

a pixel chrominance processing sub-unit, configured to determine that an absolute value of each ΔU1 is smaller than a first preset U value, and determine that an absolute value of ΔU2 having the smallest absolute value in each ΔU2 is greater than a second preset U value, Setting a chromaticity value of the current pixel point to an average value of chrominance values of each of the neighboring pixel points; and determining that an absolute value of each ΔV1 is smaller than a first preset V value, and determining each ΔV2 When the absolute value of ΔV2 with the smallest absolute value is greater than the second preset V value, the chrominance value of the current pixel point is set to the average value of the chrominance values of each of the neighboring pixel points.

It should be noted that the neighboring pixel points of the current pixel point described above can be understood as current. Four pixels above, below, to the left and to the right of the pixel. Of course, if the current pixel is at the edge of the image, the neighboring pixels of the pixel may be less than four, and only the remaining neighbor pixels need to be considered.

The apparatus for removing singular noise provided by the embodiment of the present application performs the following process for calculating each pixel point in an image to be sent to the encoder: calculating brightness of two or two pixel points among several neighboring pixel points of the current pixel point And a difference between the difference and the chrominance, obtaining a plurality of first luminance differences and a plurality of first chrominance differences; calculating a luminance difference and a chrominance difference between the current pixel and each of the neighboring pixels to obtain a plurality of second luminances a difference value and a plurality of second chromaticity difference values; determining that the absolute value of each of the first brightness difference values is smaller than a first preset brightness threshold, and wherein the second brightness of each of the second brightness difference values is the smallest When the absolute value of the difference is greater than the second preset brightness threshold, setting the brightness value of the current pixel point to an average value of the brightness values of each of the neighboring pixel points; determining each of the first chromaticity difference values The absolute value of the second chromaticity difference value is smaller than the second preset chromaticity threshold, and the absolute value of the second chromaticity difference value of each of the second chromaticity difference values is greater than the second preset chromaticity threshold The chrominance value of the current pixel is set to each of the neighbor images Point average chroma values. Through the above process, the singular noise in the image is removed, and the user's experience is improved.

Finally, it should also be noted that in this context, relational terms such as first and second are used merely to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply these entities. There is any such actual relationship or order between operations. Furthermore, the term "comprises" or "comprises" or "comprises" or any other variations thereof is intended to encompass a non-exclusive inclusion, such that a process, method, article, or device that comprises a plurality of elements includes not only those elements but also Other elements, or elements that are inherent to such a process, method, item, or device. An element that is defined by the phrase "comprising a ..." does not exclude the presence of additional equivalent elements in the process, method, item, or device that comprises the element.

The various embodiments in the present specification are described in a progressive manner, and each embodiment focuses on differences from other embodiments, and the same similar parts between the various embodiments may be referred to each other.

The above description of the disclosed embodiments enables one skilled in the art to implement or make Use this application. Various modifications to these embodiments are obvious to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the application. Therefore, the application is not limited to the embodiments shown herein, but is to be accorded the broadest scope of the principles and novel features disclosed herein.

Claims (8)

1. A method of removing singular noise, characterized in that the following process is performed for each pixel in an image to be transmitted to an encoder:

   Calculating a luminance difference value and a chrominance difference value of two or two pixel points of the plurality of neighboring pixel points of the current pixel point, obtaining a plurality of first luminance difference values and a plurality of first chrominance difference values; calculating the current pixel point and each of the foregoing a luminance difference value and a chrominance difference value of neighboring pixels, to obtain a plurality of second luminance difference values and a plurality of second chrominance difference values;

   Determining whether an absolute value of each of the first brightness difference values is less than a first preset brightness threshold;

   If yes, determining whether an absolute value of the second brightness difference value whose absolute value is the smallest among the second brightness difference values is greater than a second preset brightness threshold value;

   If yes, setting a brightness value of the current pixel point to an average value of brightness values of each of the neighboring pixel points;

   Determining whether an absolute value of each of the first chromaticity difference values is less than a first preset chromaticity threshold;

   If yes, determining whether an absolute value of the second chromaticity difference value whose absolute value is the smallest among the second chromaticity difference values is greater than a second preset chromaticity threshold value;

   If so, the chrominance value of the current pixel point is set to an average value of the chrominance values of each of the neighboring pixel points.
2. The method according to claim 1, wherein when the image is an image of the YUV format, the calculated first luminance difference value is ΔY1, and the first chrominance difference values are ΔU1 and ΔV1, and the second luminance difference The value is ΔY2, the second chromaticity difference is ΔU2 and ΔV2, and the first preset chromaticity threshold includes a first preset U value and a first preset V value, and the second preset chromaticity threshold The second preset U value and the second preset V value are included;

   Determining whether an absolute value of each of the first chromaticity difference values is smaller than a first preset chromaticity threshold value, and determining a minimum value of each of the second chromaticity difference values when the determination result is YES The process of whether the absolute value of the dichromatic difference value is greater than the second preset chroma threshold is:

   Determining whether an absolute value of each ΔU1 is smaller than a first preset U value;

   When determining that the absolute value of each ΔU1 is less than the first preset U value, determining whether the absolute value of ΔU2 with the smallest absolute value in each ΔU2 is greater than the second preset U value;

   Determining whether an absolute value of each ΔV1 is smaller than a first preset V value;

   When it is determined that the absolute value of each ΔV1 is smaller than the first preset V value, it is judged whether or not the absolute value of ΔV2 whose absolute value is the smallest among the respective ΔV2 is greater than the second preset V value.
3. The method according to claim 2, wherein the setting the chrominance value of the current pixel point to an average value of chrominance values of each of the neighboring pixel points comprises:

   When determining that the absolute value of each ΔU1 is smaller than the first preset U value, and determining that the absolute value of ΔU2 whose absolute value is the smallest among the ΔU2 is greater than the second preset U value, the chromaticity value of the current pixel point is set to The average of the chrominance values of each of the neighboring pixel points; and,

   When determining that the absolute value of each ΔV1 is less than the first preset V value, and determining that the absolute value of ΔV2 whose absolute value is the smallest among the ΔV2 is greater than the second preset V value, the chromaticity value of the current pixel point is set to The average of the chrominance values of each of the neighboring pixel points.
4. The method according to any one of claims 1-3, wherein the plurality of neighboring pixel points of the current pixel point are:

   Four pixels above, below, to the left, and to the right of the current pixel.
5. A device for removing singular noise, characterized in that each pixel in an image to be transmitted to an encoder is processed, the device comprising:

   a first calculating unit, configured to calculate a luminance difference value and a chrominance difference value of two or two pixel points of the plurality of neighboring pixel points of the current pixel point, to obtain a plurality of first brightness difference values and a plurality of first chromaticity difference values;

   a second calculating unit, configured to calculate a luminance difference value and a chrominance difference value between the current pixel point and each of the neighboring pixel points, to obtain a plurality of second brightness difference values and a plurality of second chromaticity difference values;

   a first determining unit, configured to determine whether an absolute value of each of the first brightness difference values is smaller than a first preset brightness threshold;

   a second determining unit, configured to determine, when the first determining unit determines that the value is YES, whether the absolute value of the second brightness difference value whose absolute value is the smallest among the second brightness difference values is greater than the second preset brightness threshold ;

   a pixel brightness processing unit, configured to set a brightness value of the current pixel point to an average value of brightness values of each of the neighboring pixel points when the second determining unit determines to be YES;

   a third determining unit, configured to determine whether an absolute value of each of the first chrominance differences is less than a first preset chromaticity threshold;

   a fourth determining unit, configured to determine, when the third determining unit determines that the value is YES, whether the absolute value of the second chromaticity difference value whose absolute value is the smallest among the second chromaticity difference values is greater than the second preset color Degree threshold

   And a pixel chrominance processing unit configured to set a chromaticity value of the current pixel point to an average value of chromaticity values of each of the neighboring pixel points when the fourth determining unit determines that the value is YES.
6. The apparatus according to claim 5, wherein when the image is an image of the YUV format, the calculated first luminance difference value is ΔY1, and the first chrominance difference values are ΔU1 and ΔV1, and the second luminance difference The value is ΔY2, the second chromaticity difference is ΔU2 and ΔV2, and the first preset chromaticity threshold includes a first preset U value and a first preset V value, and the second preset chromaticity threshold The second preset U value and the second preset V value are included;

   The third determining unit includes:

   a first U value determining unit, configured to determine whether an absolute value of each ΔU1 is smaller than a first preset U value;

   a first V value determining unit, configured to determine whether an absolute value of each ΔV1 is smaller than a first preset V value;

   The fourth determining unit includes:

   a second U value judging unit, configured to determine, when the first U value judging unit judges that the absolute value of each ΔU1 is smaller than the first preset U value, whether the absolute value of ΔU2 having the smallest absolute value in each ΔU2 is greater than the second pre- Set the U value;

   The second V value determining unit is configured to determine, when the first V value determining unit determines that the absolute value of each ΔV1 is smaller than the first preset V value, whether the absolute value of the ΔV2 with the smallest absolute value in each ΔV2 is greater than the second pre- Set the V value.
7. The apparatus according to claim 6, wherein the pixel chrominance processing unit comprises:

   a pixel chrominance processing sub-unit, configured to determine that an absolute value of each ΔU1 is smaller than a first preset U value, and determining that an absolute value of ΔU2 having the smallest absolute value in each ΔU2 is greater than a second preset U value The chromaticity value of the current pixel point is set as an average value of chrominance values of each of the neighboring pixel points; and, in determining that the absolute value of each ΔV1 is smaller than the first preset V value, and determining that the absolute value of each ΔV2 is the smallest When the absolute value of ΔV2 is greater than the second predetermined V value, the chrominance value of the current pixel point is set to an average value of the chrominance values of each of the neighboring pixel points.
8. Apparatus according to any of claims 5-7, wherein said current pixel The number of neighbor pixels of the point is:

   Four pixels above, below, to the left, and to the right of the current pixel.

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