CN113473132B - Transparent video compression method, device, storage medium and terminal - Google Patents

Abstract

The embodiment of the application discloses a transparent video compression method, a device, a storage medium and a terminal, wherein the method comprises the following steps: acquiring size information, first color information and first transparency information of an initial frame image in an initial video, wherein the first transparency information comprises first transparency of each pixel point in the initial frame image, generating a blank frame image corresponding to the initial frame image, the blank frame image comprises a color area and a transparent area, the size information of the color area and the size information of the transparent area are identical to the size information of the initial frame image, writing the first color information into the color area, writing second color information obtained after compression processing of each first transparency into the transparent area, obtaining a target frame image corresponding to the initial frame image, and generating a target video based on the target frame image corresponding to each initial frame image. The method and the device reserve the transparency of all pixel points in the initial video, and can avoid the problem that the compressed transparent video is distorted during restoration.

Description

Transparent video compression method, device, storage medium and terminal

Technical Field

The present application relates to the field of computer technology, and in particular to a transparent video compression method, device, storage medium and terminal.

Background technique

The alpha channel value is used to represent transparency data and represents the transparency of the pixel. The alpha channel value can be expressed as a percentage or as a value between 0 and 255. If a pixel's alpha channel value is 0%, it is completely transparent (that is, invisible), while a value of 100% means a completely opaque pixel (traditional digital images). Values between 0% and 100% allow the pixel to show through the background.

In the related art, when compressing transparent videos with alpha channel values, lossy compression is usually used. As the lossy compression ratio increases, the loss increases. When restoring the transparent video, details will be lost, resulting in video distortion.

Summary of the invention

The embodiments of the present application provide a transparent video compression method, device, computer storage medium and terminal, which can avoid the problem of distortion of the compressed transparent video when restoring it. The technical solution is as follows:

In a first aspect, an embodiment of the present application provides a transparent video compression method, the method comprising:

Acquire size information, first color information, and first transparency information of an initial frame image in an initial video, where the first transparency information includes a first transparency of each pixel in the initial frame image;

Generate a blank frame image corresponding to the initial frame image, wherein the blank frame image includes a color area and a transparent area, and size information of the color area and size information of the transparent area are the same as size information of the initial frame image;

Writing the first color information into the color area, and writing the second color information obtained after compressing each of the first transparency into the transparent area, to obtain a target frame image corresponding to the initial frame image;

A target video is generated based on the target frame images corresponding to each of the initial frame images.

In a second aspect, an embodiment of the present application provides a transparent video compression device, the device comprising:

An information acquisition module, used to acquire size information, first color information, and first transparency information of an initial frame image in an initial video, wherein the first transparency information includes a first transparency of each pixel in the initial frame image;

An image frame generation module, used to generate a blank frame image corresponding to the initial frame image, wherein the blank frame image includes a color area and a transparent area, and the size information of the color area and the size information of the transparent area are the same as the size information of the initial frame image;

An image frame processing module, used for writing the first color information into the color area, and writing the second color information obtained after compressing each of the first transparency into the transparent area, so as to obtain a target frame image corresponding to the initial frame image;

The video generation module is used to generate a target video based on the target frame images corresponding to each of the initial frame images.

In a third aspect, an embodiment of the present application provides a computer storage medium, wherein the computer storage medium has a plurality of instructions, and the instructions are suitable for being loaded by a processor and executing the above-mentioned method steps.

In a fourth aspect, an embodiment of the present application provides a terminal, which may include: a memory and a processor; wherein the memory stores a computer program, and the computer program is suitable for being loaded by the memory and executing the above-mentioned method steps.

The beneficial effects brought by the technical solution provided by the embodiment of the present application include at least:

When the scheme of the embodiment of the present application is executed, the size information, first color information and first transparency information of the initial frame image in the initial video are obtained, the first transparency information includes the first transparency of each pixel in the initial frame image, and a blank frame image corresponding to the initial frame image is generated, the blank frame image includes a color area and a transparent area, the size information of the color area and the size information of the transparent area are the same as the size information of the initial frame image, the first color information is written into the color area, and the second color information obtained after the first transparency is compressed is written into the transparent area, the target frame image corresponding to the initial frame image is obtained, and the target video is generated based on the target frame images corresponding to the initial frame images. The present application retains the transparency of all pixels in the initial frame image by writing the color information obtained by compressing the transparency of all pixels in the initial frame image into the transparent area, and then generates a compressed initial video based on each target frame image composed of the transparent area and the color area, thereby retaining the transparency of all pixels in the initial video and not losing details, thereby avoiding the problem of distortion of the compressed transparent video when it is restored.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

FIG1 is a schematic diagram of a flow chart of a transparent video compression method provided in an embodiment of the present application;

FIG2 is a schematic diagram of a principle for generating a blank frame image provided by an embodiment of the present application;

FIG3 is a schematic diagram of a flow chart of another transparent video compression method provided in an embodiment of the present application;

FIG4 is a schematic diagram of a principle for generating a target frame image provided by an embodiment of the present application;

FIG5 is a flow chart of another transparent video compression method provided in an embodiment of the present application;

FIG6 is a schematic diagram of the structure of a transparent video compression device provided in an embodiment of the present application;

FIG. 7 is a schematic diagram of the structure of a terminal provided in an embodiment of the present application.

Detailed ways

In order to make the purpose, features, and advantages of the embodiments of the present application more obvious and understandable, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

In the description of the present application, it should be understood that the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In the description of the present application, it should be noted that, unless otherwise clearly specified and limited, "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood in specific circumstances. In addition, in the description of the present application, unless otherwise specified, "multiple" refers to two or more. "And/or" describes the association relationship of associated objects, indicating that there can be three relationships, for example, A and/or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone. The character "/" generally indicates that the associated objects before and after are an "or" relationship.

In the related art, regarding the transparent video solution, the video content consists of two areas, namely the color area and the transparent area. For the compression solution of the transparent video, one is to use the MPEG-2 format to perform specific video encoding on the video to achieve transparent area compression; the other is to compress the size of the transparent area proportionally when generating the video, and restore the transparent area by interpolation when playing the video.

Obviously, the above two methods of compressing transparent videos are actually lossy compression methods. As the compression ratio increases, the loss increases. When the compression ratio is large, the transparency restored during playback is distributed in a stepped/blocky manner, which will lose details and cause video distortion.

For ease of understanding, the terms involved in the embodiments of the present application are explained.

The first color information is used to represent the R value, G value, and B value of all pixels in each initial frame image.

The first transparency information is used to represent the transparency value of all pixels in each initial frame image (that is, the alpha channel value, represented by A). For example, if the RGBA values of a pixel are: R=255, G=0, B=0, A=151, then the first color information includes R=255, G=0, B=0, and the first transparency information includes A=151.

Second color information: used to represent the second R value, the second G value, and the second B value obtained after the transparency values of all pixels in each initial frame image are compressed.

The present application is described in detail below with reference to specific embodiments.

In the following method embodiments, for the sake of convenience, only the execution subject of each step is introduced and described as the terminal.

Please refer to Figure 1, which is a flow chart of a transparent video compression method provided in an embodiment of the present application. As shown in Figure 1, the method in the embodiment of the present application may include the following steps:

S101, obtaining size information, first color information, and first transparency information of an initial frame image in an initial video, where the first transparency information includes a first transparency of each pixel in the initial frame image.

The initial video refers to a video with a transparency channel, that is, in addition to the RGB three-color information, the initial video also has alpha channel information. The alpha channel is generally used as an opacity parameter. If the alpha channel value of a pixel is 0%, it is completely transparent (that is, invisible), and a value of 100% means a completely opaque pixel (traditional digital image), and a value between 0% and 100% allows the pixel to show through the background. The alpha channel value can be expressed as a percentage, an integer, or a real number from 0 to 1 like the RGB parameter.

The size information refers to the width and height of each initial frame image in the initial video, which respectively represent the number of pixels of the initial frame image in the horizontal direction and the vertical direction.

Specifically, each initial frame image of the initial video may be exported according to the video frame rate through a video tool, and size information, first color information, and first transparency information of each initial frame image may also be obtained.

S102, generating a blank frame image corresponding to the initial frame image, wherein the blank frame image includes a color area and a transparent area, and size information of the color area and size information of the transparent area are the same as size information of the initial frame image.

Among them, the blank frame image refers to an image whose size is twice the size of the initial frame image. The double size mentioned here can be understood as, on the one hand, the width value of the blank frame image is twice the width value of the initial frame image, and the height value of the blank frame image is equal to the height value of the initial frame image; on the other hand, it can be understood as, the width value of the blank frame image is equal to the width value of the initial frame image, and the height value of the blank frame image is equal to twice the height value of the initial frame image.

Among them, the color area can be understood as an area for storing the R value, G value and B value of all pixels in the initial frame image, and the position of each pixel in the color area is the same as the position of each pixel in the initial frame image. The transparent area can be understood as an area for storing the second R value, the second G value and the second B value of all pixels in the initial frame image. The second R value is not equal to the R value in the color area, the second G value is not equal to the G value in the color area, and the second B value is not equal to the B value in the color area. The specific assignment process of the second R value, the second G value and the second B value can be referred to S103. The position of each pixel in the transparent area is the same as the position of each pixel in the initial frame image. Since the width value and height value of the color area, the width value and height value of the transparent area, and the width value and height value of the initial frame image are the same, the position of each pixel in the initial frame image is fixed, so the position of each pixel can also be fixed in the color area and the transparent area.

According to some embodiments, referring to the schematic diagram shown in FIG. 2, 201 is an initial frame image. On the one hand, 2021 and 2022 form a blank frame image. The sizes of 2021 and 2022 are respectively the same as 201. 2021 can be a color area, 2021 can be a transparent area, or 2021 can be a transparent area, and 2022 can be a color area. On the other hand, 2031 and 2032 form a blank frame image. The sizes of 2031 and 2032 are respectively the same as 201. 2031 can be a color area, 2031 can be a transparent area, or 2031 can be a transparent area, and 2032 can be a color area.

S103, writing the first color information into the color area, and writing the second color information obtained after compression processing of each of the first transparencies into the transparent area, to obtain a target frame image corresponding to the initial frame image.

Among them, the first color information refers to the R value, G value and B value of all pixels in the initial frame image, and the second color information refers to the second R value, second G value and second B value obtained after compression processing of the transparency value (first transparency, that is, A value) of all pixels in the initial frame image.

Specifically, the process of obtaining the second R value, the second G value and the second B value after compressing the first transparency of each pixel can be understood as using three formulas, substituting the A value into the three formulas respectively, to obtain the second R value, the second G value and the second B value. The main function of these three formulas is to convert the larger A value into the smaller second R value, the second G value and the second B value, that is, the second R value, the second G value and the second B value are all less than or equal to the A value. Optionally, the second R value can be equal to the second G value, or the second G value can be equal to the second B value, or the second R value can be equal to the second B value. Further, the color area is filled with the R value, G value and B value of each pixel, and the transparent area is filled with the second R value, the second G value and the second B value of each pixel. Since the color area and the transparent area are initially blank frame images, the blank frame image filled with color component values becomes the target frame image.

Generally, if the value of a single color component among the three color components of the pixel point R value, G value, and B value is smaller, and the difference between the single color component values is smaller (the difference between the single color components is closer to 0), the volume increment of the compressed transparent video is smaller. The embodiment of the present application is based on this principle and compresses the first transparency into a smaller color component value.

S104: Generate a target video based on the target frame images corresponding to the initial frame images.

The target video is a video compressed from the initial video, that is, the target video is a compressed transparent video. Specifically, the process of generating the target video from each target frame image can be understood as the process of compressing and encoding each target frame image to generate the target video. Generally, digital video compression coding methods are hybrid coding, that is, combining transform coding, motion estimation and motion compensation, and entropy coding to perform compression coding.

The function of transform coding is to transform the image signal described in the spatial domain into the frequency domain, and then encode the transformed coefficients. Generally speaking, images have strong correlation in space, and transforming them into the frequency domain can achieve decorrelation and energy concentration. Commonly used orthogonal transforms include discrete Fourier transform, discrete cosine transform, etc. The most widely used in the digital video compression process is discrete cosine transform.

Entropy coding is named because the average code length after coding is close to the entropy value of the source. Entropy coding is often implemented using variable length coding (VLC). The basic principle is to assign short codes to symbols with a high probability of appearing in the source, and assign long codes to symbols with a low probability of appearing, so as to obtain a shorter average code length statistically. Variable length coding usually includes Huffman coding, arithmetic coding, run-length coding, etc. Among them, run-length coding is a very simple compression method. Its compression efficiency is not high, but its encoding and decoding speeds are fast. It is still widely used, especially when run-length coding is used after transform coding, which has a good effect.

Motion estimation and motion compensation are effective means to eliminate the temporal correlation of image sequences. The methods of DCT transformation, quantization, and entropy coding are performed on the basis of a frame of image. These methods can eliminate the spatial correlation between pixels within the image. In fact, in addition to spatial correlation, image signals also have temporal correlation. For example, for digital videos such as the news broadcast with a static background and small motion of the main body of the picture, the difference between each picture is small, and the correlation between the pictures is large. In this case, we do not need to encode each frame of the image separately, but can only encode the changed parts of adjacent video frames, thereby further reducing the amount of data. This work is achieved by motion estimation and motion compensation.

In practical applications, the above encoding methods are not separated, and they are usually used in combination to achieve the best compression effect.

When the scheme of the embodiment of the present application is executed, the size information, first color information and first transparency information of the initial frame image in the initial video are obtained, the first transparency information includes the first transparency of each pixel in the initial frame image, a blank frame image corresponding to the initial frame image is generated, the blank frame image includes a color area and a transparent area, the size information of the color area and the size information of the transparent area are the same as the size information of the initial frame image, the first color information is written into the color area, and the second color information obtained after the compression processing of each first transparency is written into the transparent area, the target frame image corresponding to the initial frame image is obtained, and the target video is generated based on the target frame images corresponding to each of the initial frame images. The present application retains the transparency of all pixels in the initial video by writing the color information obtained by compressing the transparency of all pixels in the initial frame image into the transparent area, and then generates a compressed initial video based on each target frame image composed of the transparent area and the color area. The problem of distortion in the compressed transparent video can be avoided.

In the following method embodiments, for the sake of convenience, only the execution subject of each step is introduced and described as the terminal.

Please refer to Figure 3, which is a flow chart of a transparent video compression method provided in an embodiment of the present application. As shown in Figure 3, the method in the embodiment of the present application may include the following steps:

S301, obtaining size information, first color information, and first transparency information of an initial frame image in an initial video, where the first transparency information includes a first transparency of each pixel in the initial frame image.

S302, generating a blank frame image corresponding to the initial frame image, wherein the blank frame image includes a color area and a transparent area, and size information of the color area and size information of the transparent area are the same as size information of the initial frame image.

S303: Write the first color information into the color area.

Specifically, S301 - S303 may refer to S101 - S103 in FIG. 1 , which will not be described in detail here.

S304: Determine the target transparency with the highest proportion in the first transparency information.

Specifically, since the first transparency information refers to the first transparency of all pixels in each initial frame image, determining the target transparency with the highest proportion can be understood as selecting the first transparency with the highest frequency from the first transparency and taking the first transparency with the highest frequency as the target transparency. Therefore, for each initial frame image in the initial video, each initial frame image will have a target transparency.

For example, there are 959*959 pixels in an initial frame image, and the first transparency of these pixels can be 100, 125, 130, 134, 135, 136, etc. The transparency value range here is 0-255. The most frequently occurring value in the above first transparency is 134. Then for the initial frame image, the target transparency can be 134.

S305, obtaining the correspondence between different compression ratios and different compression volumes of the target video under the target transparency, selecting the compression ratio with the smallest compression volume from the different compression ratios, and using the compression ratio with the smallest compression volume as the compression ratio corresponding to the target transparency.

The compression ratio refers to a compression value used to compress the first transparency. For details on how to use the compression ratio to compress the first transparency, please refer to the description of S307 below.

Specifically, for the target transparency, a plurality of different compression ratios can be pre-set, and after compressing the target transparency with a plurality of compression ratios, the second color information of each pixel in the initial frame image can be obtained. Furthermore, the target frame image corresponding to the initial frame image can be obtained, and after the target frame image is compressed and encoded, a compressed transparent video, that is, the target video, can be obtained. The volume of the target video at this time can be called the compressed volume. It can be understood that for the same target transparency, the compressed volumes obtained by different compression ratios are also different. Then, the compression ratio with the smallest compressed volume can be selected, and the compression ratio with the smallest compressed volume can be used as the target compression ratio. Because the purpose of compressing the transparent video is also to achieve a smaller compressed volume effect.

For example, the target transparency is 134, and the preset compression ratios are 15 integers in the range of 1-15. Among the compression volumes corresponding to these 15 compression ratios, the compression volume corresponding to the integer 13 is the smallest. Therefore, 13 can be used as the target compression ratio for the target transparency of 134.

S306: Using the compression ratio corresponding to the target transparency as the target compression ratio corresponding to the initial frame image.

Specifically, as can be seen from S304-S305, the target transparency is the selected transparency for each initial frame image, and the compression ratio corresponding to the target transparency can be used as the target compression ratio of the initial frame image. In other words, the first transparency of all pixels in the initial frame image can be compressed according to the target compression ratio. For details, see S307, which will not be repeated here.

S307, compressing each of the first transparencies according to the target compression ratio to obtain second color information of each pixel in the color area, and writing the second color information into the transparent area to obtain a target frame image corresponding to the initial frame image.

Specifically, each of the first transparencies is compressed according to the target compression ratio. It can be understood that a preset formula is used. The preset formula is related to the target compression ratio. Different target compression ratios may correspond to different formulas. The first transparency of each pixel point can be substituted into the formula to obtain the second R value, second G value and second B value of each pixel point, and the second R value, second G value and second B value of each pixel point are written into the position of each pixel point in the transparent area respectively. Furthermore, the transparent area filled with the second color information and the color area filled with the first color information can constitute the target frame image.

For example, ratio represents the target compression ratio, R1 represents the second R value, G1 represents the second G value, B1 represents the second B value, and A represents the first transparency of each pixel. In the embodiment of the present application, according to different target compression ratios, the pre-set formula may be:

(1) ratio = 1, R1 = A, G1 = 0, B1 = 0;

(2)ratio＝2, G1＝R1,B1＝A-R1*2;

(3)ratio≥3, G1＝R1, B1＝A-R1*(ratio-1).

For example, see the schematic diagram of the principle of generating the target frame image as shown in FIG4 , 401 represents the initial frame image, 4021 represents the color area in the blank frame image, 4022 represents the transparent area in the blank frame image, and the RGBA values of a certain pixel in 401 are: R=255, G=0, B=0, A=156; the target transparency of the initial frame image shown in 401 is 255, and the target compression ratio corresponding to 255 is 10, then the A value of the pixel point can be substituted into the above formula (3), and R1=15, G1=15, B1=21 can be obtained. Therefore, R=255, G=0, B=0 can be filled into the position where the pixel point is located in the color area 4021, and R1=15, G1=15, B1=21 can be filled into the position where the pixel point is located in the transparent area 4022.

S308: Generate a target video based on the target frame images corresponding to the initial frame images.

For details, please refer to S104 in FIG. 1 , which will not be described in detail here.

S309, writing the target compression ratio, the size information of the color area, and the size information of the transparent area into the target video.

Among them, the size information of the color area includes not only the width value and height value of the color area, but also the area range occupied by the color area in the blank frame image. Similarly, the size information of the transparent area includes not only the width value and height value of the transparent area, but also the area range occupied by the transparent area in the blank frame image. For example, referring to the principle schematic diagram of the blank frame image shown in FIG2, if 201 represents the initial frame image, 2021 represents the color area, 2022 represents the transparent area, the size of 201 is 100*100, and the sizes of 2021 and 2022 are also 100*100, but the size of the blank frame image or the target frame image composed of 2021 and 2022 can be 200*100, then the area range occupied by 2021 in the blank frame image can be a pixel area with a width value of 0-100 and a height value of 100, and the area range occupied by 2022 in the blank frame image can be a pixel area with a width value of 100-200 and a height value of 100.

Specifically, after the target video is obtained by compressing the initial video, the target compression ratio, the size information of the color area, and the size information of the transparent area can also be written into the header file of the target video. It can be understood that the frame rate and number of frames of the initial video can also be written into the header file of the target video to facilitate the subsequent decoding and decompression of the target video.

S310, when playing the target video, reading the target compression ratio, the size information of the color area, and the size information of the transparent area in the target video.

Specifically, when playing the target video, it is first necessary to obtain the target compression ratio of the target video, the size information of the color area in the target frame image, and the size information of the transparent area in the target frame image. The purpose of obtaining the target compression ratio of the target video and the size information of the transparent area in the target frame image is to restore the first transparency of each pixel in each initial frame image according to the second color information filled in the transparent area and the target compression ratio. The purpose of obtaining the size information of the color area is to obtain the R value, G value, and B value of each pixel in each initial frame image.

S311 , determining a first transparency of each pixel point in a color area in the initial frame image according to the target compression ratio and the second color information corresponding to the transparent area.

Specifically, as described in S307, when calculating the second color information of the transparent area, a preset formula can be used to calculate the second color information based on the target compression ratio and the first transparency of each pixel. Therefore, when restoring the first transparency of each pixel, the first transparency of each pixel can be obtained by performing a reverse operation according to the formula.

For example, using the example in S307, the calculation formula used in the embodiment of the present application when restoring the first transparency may be:

(1) ratio = 1, A = R1;

(2) ratio = 2, A = R1 + G1 + B1;

(3)ratio≥3,A＝R1*(ratio-2)+G1+B1.

S312, based on the first transparencies, the first color information corresponding to the color area, the size information of the color area and the size information of the transparent area, the initial frame image is obtained, and the initial video including all the initial frame images is played.

Specifically, since the first transparency of each pixel in the initial frame image has been obtained by the above calculation process, when restoring the initial frame image, it is also necessary to obtain the first color information in the color area in the target frame image, that is, the R value, G value and B value of each pixel. When reading the first color information of the color area, it can be read according to the position of each pixel in the color area. When reading the first transparencies corresponding to the second color area in the transparent area, it can also be read according to the position of each pixel in the transparent area. Because the position of each pixel in the color area and the transparent area is the same as the position of each pixel in the initial frame image. Therefore, the RGBA value of each pixel in the initial frame image can be obtained in sequence according to the position of each pixel. Furthermore, the process of obtaining the initial video through the RGBA value of each pixel is well known to those skilled in the art and will not be repeated here.

In an embodiment of the present application, the first color information of the acquired initial frame image is written into the color area in the blank frame image, and the target transparency with the highest proportion is determined in the first transparency information corresponding to each initial frame image, and then the target compression ratio corresponding to each target transparency is determined, that is, each initial frame image uses its own compression ratio to compress the first transparency of each pixel in each initial frame image to obtain the second color information of each pixel, and then write the second color into the transparent area in the blank frame image, and then the target frame image can be obtained, and then the target video can be obtained from each target frame image. Therefore, when the initial video is restored by the target video, the first transparency of each pixel can be restored according to the compression ratio and the second color information. By retaining the transparency of each pixel, lossless compression of transparent video can be achieved, and the problem of distortion of the compressed transparent video during restoration can be avoided. In addition, the process of compressing each first transparency in the present application is different from the related art, in which each color component in the transparent area may be directly equal to the transparency, but can make the value of each color component in the transparent area smaller, and the difference value between each color component smaller, so that the incremental volume of the transparent video after compression can be reduced.

Optionally, based on FIG. 3 , as shown in FIG. 5 , S304 and S306 may be replaced by S504 and S506 .

S504: Determine the target transparency with the highest proportion in the second transparency information.

The second transparency information refers to the first transparency of each pixel of all initial frame images of the initial video. In other words, the second transparency information includes the first transparency of all pixels in the initial video.

Specifically, determining the target transparency with the highest proportion in the second transparency information can be understood as selecting the first transparency with the highest frequency among the first transparency corresponding to all pixels, and taking the first transparency with the highest frequency as the target transparency. Therefore, for each initial frame image in the initial video, each initial frame image corresponds to the same target transparency.

For example, in an initial video, the first transparency of these pixels can be 0, 30, 35, 40, 50, 100, 125, 135, 136, 199, 234, etc., where the transparency value range is 0-255. The most frequently occurring value in the above first transparency is 100. Then for the initial video, the target transparency can be 100.

S506: Using the compression ratio corresponding to the target transparency as the target compression ratio corresponding to the initial frame image.

Specifically, as can be seen from S504, the target transparency is the transparency selected for the initial video, and the compression ratio corresponding to the target transparency of the initial video can be used as the target compression ratio of all initial frame images. In other words, the first transparency of all pixels in all initial frame images can be compressed according to the same target compression ratio.

In the embodiment of the present application, when selecting the target transparency, it is determined according to the transparency value of each pixel in all the initial frame images in the initial video. Therefore, when compressing the transparency value of each pixel, only one target compression ratio is selected for compression. Then, when restoring the transparency value of each pixel, only this target compression ratio is needed for restoration. By selecting a target transparency and obtaining a target compression ratio, it is possible to avoid distortion when restoring the compressed transparent video and simplify the calculation process.

Please refer to FIG6 , which is a schematic diagram of the structure of a transparent video compression device provided in an embodiment of the present application. The transparent video compression device 600 can be implemented as all or part of a terminal through software, hardware, or a combination of both. The device 600 includes:

An information acquisition module 610 is used to acquire size information, first color information, and first transparency information of an initial frame image in an initial video, where the first transparency information includes a first transparency of each pixel in the initial frame image;

An image frame generating module 620 is used to generate a blank frame image corresponding to the initial frame image, wherein the blank frame image includes a color area and a transparent area, and the size information of the color area and the size information of the transparent area are the same as the size information of the initial frame image;

An image frame processing module 630 is used to write the first color information into the color area, and write the second color information obtained after compressing each of the first transparency into the transparent area, so as to obtain a target frame image corresponding to the initial frame image;

The video generation module 640 is used to generate a target video based on the target frame images corresponding to each of the initial frame images.

Optionally, the image frame processing module 630 includes:

A first acquisition unit, used to acquire a target compression ratio corresponding to the initial frame image;

The second compression unit is used to compress each of the first transparencies according to the target compression ratio to obtain second color information of each pixel in the color area, and write the second color information into the transparent area.

Optionally, the first acquisition unit includes:

A first acquisition subunit is used to determine the target transparency with the highest proportion in the first transparency information, and determine the compression ratio corresponding to the target transparency;

The second acquisition subunit is used to use the compression ratio corresponding to the target transparency as the target compression ratio corresponding to the initial frame image.

Optionally, the first acquisition unit includes:

A third acquisition subunit is used to determine the target transparency with the highest proportion in the second transparency information, and determine the compression ratio corresponding to the target transparency, wherein the second transparency information includes the first transparency of each pixel point of all initial frame images of the initial video;

The fourth acquisition subunit is used to use the compression ratio corresponding to the target transparency as the target compression ratio corresponding to the initial frame image.

Optionally, the first acquisition subunit or the third acquisition subunit includes:

A fifth acquisition subunit, configured to acquire a correspondence between different compression ratios and different compression volumes of the target video at the target transparency;

The sixth acquisition subunit is used to select a compression ratio with the smallest compression volume from the different compression ratios, and use the compression ratio with the smallest compression volume as the compression ratio corresponding to the target transparency.

Optionally, the device 600 further includes:

The information writing module is used to write the target compression ratio, the size information of the color area and the size information of the transparent area into the target video.

A first playback module, used for reading the target compression ratio, the size information of the color area, and the size information of the transparent area in the target video when playing the target video;

A second playback module, configured to determine a first transparency of each pixel point in the color area of the initial frame image according to the target compression ratio and the second color information corresponding to the transparent area;

The third playback module is used to obtain the initial frame image based on the first transparency, the first color information corresponding to the color area, the size information of the color area and the size information of the transparent area, and play the initial video including all the initial frame images.

Optionally, the device 600 further includes:

In the first calculation module, when ratio=1, R1=A, G1=0, B1=0;

The second calculation module, when ratio = 2, G1＝R1，B1＝A-R1*2；

The third calculation module, when ratio ≥ 3, G1＝R1，B1＝A-R1*(ratio-1);

Among them, the ratio is the target compression ratio, A is the first transparency of each pixel in the initial frame image, and R1, G1 and B1 are the values of each color channel in the second color information respectively.

When the scheme of the embodiment of the present application is executed, the size information, first color information and first transparency information of the initial frame image in the initial video are obtained, the first transparency information includes the first transparency of each pixel in the initial frame image, a blank frame image corresponding to the initial frame image is generated, the blank frame image includes a color area and a transparent area, the size information of the color area and the size information of the transparent area are the same as the size information of the initial frame image, the first color information is written into the color area, and the second color information obtained after the first transparency is compressed is written into the transparent area, the target frame image corresponding to the initial frame image is obtained, and the target video is generated based on the target frame images corresponding to the initial frame images. The present application retains the transparency of all pixels in the initial video by writing the color information obtained by compressing the transparency of all pixels in the initial frame image into the transparent area, and then generates a compressed initial video based on each target frame image composed of the transparent area and the color area. The problem of distortion in the compressed transparent video can be avoided.

Please refer to Figure 7, which shows a block diagram of a terminal 700 provided by an exemplary embodiment of the present application. The terminal 700 in the present application may include one or more of the following components: a display component 701, a memory 702, and a processor 703. The display component 701 is electrically connected to the processor 703, and the processor 703 is electrically connected to the memory 702.

The display component 701 is used to play the initial video after the target video is decompressed.

The memory 702 may include a random access memory (RAM) or a read-only memory (ROM). Optionally, the memory 702 includes a non-transitory computer-readable storage medium. The memory 702 may be used to store instructions, programs, codes, code sets or instruction sets. The memory 702 may include a storage program area and a storage data area, wherein the storage program area may store instructions for implementing an operating system, instructions for implementing at least one function (such as a touch function, a sound playback function, an image playback function, etc.), instructions for implementing the above-mentioned various method embodiments, etc. The operating system may be an Android system (including a system deeply developed based on an Android system), an IOS system developed by Apple (including a system deeply developed based on an IOS system) or other systems. The storage data area may also store data (such as a phone book, audio and video data, chat record data) created by the terminal 700 during use.

The processor 703 may include one or more processing cores. The processor 703 uses various interfaces and lines to connect the various parts of the entire terminal 700, and executes various functions and processes data of the terminal 700 by running or executing instructions, programs, code sets or instruction sets stored in the memory 702, and calling data stored in the memory 702. Optionally, the processor 703 can be implemented in at least one hardware form of DSP, Field-Programmable Gate Array (FPGA), and Programmable Logic Array (PLA). The processor 703 can integrate one or a combination of CPU, Graphics Processing Unit (GPU), and modem. Among them, the CPU mainly processes the operating system, user interface, and application programs; the GPU is responsible for rendering and drawing the content to be displayed on the touch display; and the modem is used to process wireless communications. It can be understood that the above-mentioned modem may not be integrated into the processor 703, but may be implemented separately through a communication chip. In an embodiment of the present application, the processor 703 can obtain the size information, first color information and first transparency information of the initial frame image in the initial video, wherein the first transparency information includes the first transparency of each pixel in the initial frame image, and generate a blank frame image corresponding to the initial frame image, wherein the blank frame image includes a color area and a transparent area, and the size information of the color area and the size information of the transparent area are the same as the size information of the initial frame image, and the first color information is written into the color area, and the second color information obtained after the compression processing of each first transparency is written into the transparent area, so as to obtain the target frame image corresponding to the initial frame image, and then generate the target video based on the target frame images corresponding to each of the initial frame images. Therefore, by writing the color information obtained after compressing the transparency of all pixels in the initial frame image into the transparent area, and then generating the compressed initial video based on each target frame image composed of the transparent area and the color area, the transparency of all pixels in the initial video is retained, and the problem of distortion of the compressed transparent video when it is restored can be avoided.

Optionally, the display component 701 in the terminal 700 may also include a touch screen, which may be a capacitive touch screen, which is used to receive a touch operation on or near it by a user using any suitable object such as a finger, a touch pen, etc., and to display the user interface of each application. The touch screen is usually arranged on the front panel of the terminal 700. The touch screen may be designed as a full screen, a curved screen, or a special-shaped screen. The touch screen may also be designed as a combination of a full screen and a curved screen, or a combination of a special-shaped screen and a curved screen, which is not limited in the embodiments of the present application.

Optionally, the terminal 700 may further include at least one of the speaker components, and the processor 703 is electrically connected to the speaker component. The processor 703 is used to control the speaker component through a driver to play the audio of the initial video obtained by decompressing the target video.

In addition, those skilled in the art will appreciate that the structure of the terminal 700 shown in the above figures does not constitute a limitation on the terminal 700, and the terminal may include more or fewer components than shown, or combine certain components, or arrange the components differently. For example, the terminal 700 also includes a radio frequency circuit, an audio circuit, a wireless fidelity (WiFi) component, a power supply, a Bluetooth component, and other components, which will not be described in detail here.

An embodiment of the present application further provides a computer-readable storage medium, which stores at least one instruction, and the at least one instruction is used to be executed by a processor to implement the transparent video compression method as described in the above embodiments.

An embodiment of the present application also provides a computer program product, which stores at least one instruction, and the at least one instruction is loaded and executed by the processor to implement the transparent video compression method described in the above embodiments.

Those skilled in the art should be aware that in one or more of the above examples, the functions described in the embodiments of the present application can be implemented with hardware, software, firmware, or any combination thereof. When implemented using software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or codes on a computer-readable medium. Computer-readable media include computer storage media and communication media, wherein the communication media include any media that facilitates the transmission of a computer program from one place to another. The storage medium can be any available medium that a general or special-purpose computer can access.

The above description is only an optional embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims (10)

1. A transparent video compression method, characterized in that the method comprises: Acquire size information, first color information, and first transparency information of an initial frame image in an initial video, where the first transparency information includes a first transparency of each pixel in the initial frame image; Generate a blank frame image corresponding to the initial frame image, wherein the blank frame image includes a color area and a transparent area, and size information of the color area and size information of the transparent area are the same as size information of the initial frame image; Writing the first color information into the color area, and writing the second color information obtained after compressing each of the first transparency into the transparent area, to obtain a target frame image corresponding to the initial frame image; A target video is generated based on the target frame images corresponding to each of the initial frame images. 2. The method according to claim 1, wherein the step of writing the second color information obtained after compressing each of the first transparency into the transparent area comprises: Obtaining a target compression ratio corresponding to the initial frame image; The first transparencies are compressed respectively according to the target compression ratio to obtain second color information of each pixel in the color area, and the second color information is written into the transparent area. 3. The method according to claim 2, characterized in that the step of obtaining the target compression ratio corresponding to the initial frame image comprises: Determine the target transparency with the highest proportion in the first transparency information, and determine the compression ratio corresponding to the target transparency; The compression ratio corresponding to the target transparency is used as the target compression ratio corresponding to the initial frame image. 4. The method according to claim 2, characterized in that the step of obtaining the target compression ratio corresponding to the initial frame image comprises: Determining the target transparency with the highest proportion in the second transparency information, and determining the compression ratio corresponding to the target transparency, wherein the second transparency information includes the first transparency of each pixel point of all initial frame images of the initial video; The compression ratio corresponding to the target transparency is used as the target compression ratio corresponding to the initial frame image. 5. The method according to claim 3 or 4, characterized in that the step of determining the compression ratio corresponding to the target transparency comprises: Acquire a correspondence between different compression ratios and different compression volumes of the target video at the target transparency; A compression ratio with the smallest compression volume is selected from the different compression ratios, and the compression ratio with the smallest compression volume is used as the compression ratio corresponding to the target transparency. 6. The method according to any one of claims 2 to 4, characterized in that the method further comprises: Writing the target compression ratio, the size information of the color area, and the size information of the transparent area into the target video; When playing the target video, reading the target compression ratio, the size information of the color area, and the size information of the transparent area in the target video; Determining a first transparency of each pixel point in the color area of the initial frame image according to the target compression ratio and the second color information corresponding to the transparent area; Based on the first transparencies, the first color information corresponding to the color area, the size information of the color area, and the size information of the transparent area, the initial frame image is obtained, and the initial video including all the initial frame images is played. 7. The method according to any one of claims 2 to 4, characterized in that the relationship between the target compression ratio and the second color information is: If ratio = 1, then R1 = A, G1 = 0, B1 = 0; If ratio = 2, then G1＝R1，B1＝A-R1*2； If ratio ≥ 3, then G1＝R1，B1＝A-R1*(ratio-1); Among them, the ratio is the target compression ratio, A is the first transparency of each pixel in the initial frame image, and R1, G1 and B1 are the values of each color channel in the second color information respectively. 8. A transparent video compression device, characterized in that the device comprises: An information acquisition module, used to acquire size information, first color information, and first transparency information of an initial frame image in an initial video, wherein the first transparency information includes a first transparency of each pixel in the initial frame image; An image frame generation module, used to generate a blank frame image corresponding to the initial frame image, wherein the blank frame image includes a color area and a transparent area, and the size information of the color area and the size information of the transparent area are the same as the size information of the initial frame image; An image frame processing module, used for writing the first color information into the color area, and writing the second color information obtained after compressing each of the first transparency into the transparent area, so as to obtain a target frame image corresponding to the initial frame image; The video generation module is used to generate a target video based on the target frame images corresponding to each of the initial frame images. 9. A computer storage medium, characterized in that the computer storage medium stores a plurality of instructions, wherein the instructions are suitable for being loaded by a processor and executing the method steps according to any one of claims 1 to 7. 10. A terminal, comprising: a processor and a memory; wherein the memory stores a computer program, and the computer program is suitable for being loaded by the processor and executing the method steps according to any one of claims 1 to 7.