KR101313335B1 - Encoding Interval Configuration Method and Apparatus, Video Multiple Encoding Method and Apparatus Using Same and Computer Readable Recording Medium Therefor - Google Patents

Abstract

The present invention relates to a method and apparatus for setting an encoding interval, an image multiple encoding method and apparatus using the same, and a computer-readable recording medium therefor.

The present invention reduces the resolution of an image, encodes a reduced-resolution image, generates encoding result information of the reduced image, corrects the encoding result information, generates encoding result information of the image, and encodes the image. An encoding interval setting apparatus is provided, wherein a plurality of encoding intervals are set by analyzing result information.

According to the present invention, by dividing an image into a plurality of coding sections and setting and updating a rate-distortion model for each section, the rate-distortion model can be simplified while being encoded using a more suitable rate-distortion model. Encoding efficiency may be improved by multiplexing an image using a rate-distortion model that is set and updated.

Multiple encoding, video, compression, rate-distortion model, update

Description

Encoding Interval Configuration Method and Apparatus, Video Multiple Encoding Method and Apparatus Using Same and Computer Readable Recording Medium Therefor}

The present invention relates to a method and apparatus for setting an encoding interval, an image multiple encoding method and apparatus using the same, and a computer-readable recording medium therefor. More particularly, the present invention relates to a method and apparatus for efficiently performing multiple encoding for encoding an image several times and a recording medium therefor.

A video consists of a group consisting of a series of pictures. The video is encoded by a picture unit or a slice or a block within a picture and output as a bitstream to be compressed. The compressed image, that is, the bitstream, is transferred to the image decoding apparatus and restored to the original image.

Image compression techniques include intra prediction encoding techniques for performing intra prediction to remove spatial overlapping elements in an image, and inter prediction encoding techniques for performing inter prediction to remove temporal overlapping elements in an image. There is this. In other words, compression is reduced by reducing the amount of encoded bits by removing temporal overlapping elements and spatial overlapping elements in an image.

In order to further improve the compression performance, such a prediction encoding technique is not only a technique for predicting an image but also a transformation technique for transforming pixel signals constituting an image into a frequency domain to generate transform coefficients, a quantization technique for quantizing transform coefficients, and a quantized transform. Various techniques such as entropy encoding technique for binarizing coefficients are included. In quantization and entropy encoding, a target amount of bits generated by the bitstream, which is the final result, is determined, and the degree of quantization and degree of binarization are determined according to the target bit amount.

The smaller the target bit amount, the smaller the bit amount of the bit stream, and the better the compression performance. However, a large amount of data is lost to satisfy the target bit amount, and the image quality of the image is deteriorated when the encoded image is decoded and decompressed. The larger the amount, the worse the compression performance due to the larger bit amount of the bitstream, but the relatively less data is lost and the quality of the reconstructed image is improved.

Therefore, since the compression performance and the image quality are determined according to the target bit amount, the encoding efficiency can be improved only by encoding in consideration of the compression performance and the image quality. A rate-distortion model is generally used as a criterion for encoding compression performance and image quality in a comprehensive manner. The rate-distortion model is also expressed as a rate-distortion curve expressed in terms of bit rate and maximum signal-to-noise ratio.

As described above, although the rate-distortion model is an important factor in determining the encoding performance, it is difficult to expect an improvement in the coding efficiency since the target bit amount is determined only in the normal video compression, according to the rate-distortion model. There is a problem.

In order to solve the above-described problem, the present invention has a main object to improve encoding efficiency by efficiently performing multiple encoding for encoding an image several times.

According to an aspect of the present invention, there is provided an apparatus for setting an image to a plurality of encoding sections, the apparatus comprising: a scaler for reducing a resolution of an image; An encoder for encoding the reduced-resolution image to generate encoding result information about the reduced image; A corrector for correcting the encoding result information to generate encoding result information of the image; And an interval setter configured to analyze encoding result information of the image to set a plurality of encoding intervals.

According to another object of the present invention, there is provided a method for setting an image to a plurality of encoding intervals, the method comprising: reducing the resolution of the image; An encoding step of encoding an image having a reduced resolution to generate encoding result information about the reduced image; A correction step of correcting the encoding result information to generate encoding result information of the image; And an interval setting step of analyzing the encoding result information of the image and setting a plurality of encoding intervals.

According to yet another object of the present invention, in an apparatus for multi-encoding an image, an image set as a plurality of encoding sections is encoded according to a rate-distortion model set for each encoding section, and the encoding result of the encoded image is pre-recorded. An encoder that encodes repeatedly until the set target encoding result is satisfied; And an updater for updating the rate-distortion model set for each of the plurality of encoding intervals according to the encoding result of the encoded image whenever the image that is set in the plurality of encoding intervals is encoded.

According to still another object of the present invention, there is provided a method of multi-encoding an image, comprising: an encoding step of encoding an image set as a plurality of encoding sections according to a rate-distortion model set for each encoding section; Determining whether the encoding result of the encoded image satisfies a predetermined target encoding result; Updating the rate-distortion model set for each of a plurality of encoding intervals according to the encoding result of the encoded image, when the encoding result of the encoded image does not satisfy the preset target encoding result; And an output step of outputting a bitstream of the encoded image when the encoding result of the encoded image satisfies a predetermined target encoding result.

According to still another object of the present invention, there is provided a computer-readable recording medium having recorded thereon a program for realizing a coding interval setting method and a video multiplexing method.

As described above, according to the present invention, by dividing an image into a plurality of coding sections and setting and updating a rate-distortion model for each section, the rate-distortion model is simplified while being encoded using a more suitable rate-distortion model. In addition, encoding efficiency may be improved by multiplexing an image using a rate-distortion model set and updated for each section.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. In adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible even though they are shown in different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

In addition, in describing the component of this invention, terms, such as 1st, 2nd, A, B, (a), (b), can be used. These terms are intended to distinguish the constituent elements from other constituent elements, and the terms do not limit the nature, order or order of the constituent elements. When a component is described as being "connected", "coupled", or "connected" to another component, the component may be directly connected or connected to the other component, Quot; may be "connected," "coupled," or "connected. &Quot;

1 is a block diagram schematically illustrating a video encoding apparatus according to a first embodiment.

The video encoding apparatus 100 according to the first embodiment includes an encoding controller 110, a predictor 120, a subtracter 130, a transformer 140, and a quantizer. Quantizer 150, an encoder 160, an inverse quantizer 170, an inverse transformer 180, and an adder 190 may be included. The video encoding apparatus 100 may be a personal computer (PC), a notebook computer, a personal digital assistant (PDA), a portable multimedia player (PMP), or a PlayStation Portable (PSP). ), A communication device such as a communication modem for communicating with various devices or a wired / wireless communication network, a memory for storing various programs and data for determining an encoding mode, and a program. It means a variety of devices having a microprocessor, etc. for execution and operation and control.

2 is a flowchart illustrating a video encoding method according to a first embodiment.

The image encoding apparatus 100 outputs a bitstream having a form of binary data by removing temporal and spatial overlapping elements included in an input image from an image and entropy encoding the image to compress a moving image.

A video is composed of several images that are temporally contiguous, that is, a picture. When a video to be encoded is input to the image encoding apparatus 100 (S210), the encoding controller 110 performs all pictures of the input video. Is encoded (S220), and if all pictures are not encoded, a target bit amount is allocated to a picture to be encoded, that is, a current picture (S230). Here, each picture constituting the video is assigned a number of bits according to a predetermined bitrate (unit: Bits per Second), and each picture is encoded by dividing into multiple macroblocks (MBs). .

The encoding controller 110 determines whether all macroblocks in the current picture are encoded by checking the macroblocks divided in the current picture (S240). If all macroblocks are not encoded, the current macroblock to be encoded currently is A target bit amount is allocated to the target bit (S250). Here, the bit amount allocated to the current macroblock is allocated within the range of bit amount allocated to the current picture in step S230.

When a bit amount is allocated to the current macroblock, encoding is performed based on the allocated bit amount. The predictor 120 predicts the current macroblock by using intra prediction or inter prediction. To generate a predicted macroblock (S260), the adder 130 subtracts the current macroblock and the predicted macroblock to generate a residual macroblock, and the converter 140 generates a residual macroblock. A transform coefficient macroblock having transform coefficients is generated by transforming the frequency domain (S262), and the quantizer 150 may encode the transform coefficients according to a predetermined bit amount. Quantized Transform Coefficient Macr by Quantization using Quantization Parameter oblock), and the encoder 160 encodes the quantized transform coefficient macroblock using a technique such as entropy coding to output a bitstream (S266). The bitstream output here is a bitstream for the corresponding macroblock.

When encoding of the macroblock is completed, the encoding controller 110 updates the rate-distortion model in units of macroblocks (S270). Here, the rate-distortion model is a model introduced to determine an optimal quantization parameter, and is represented by a peak signal to noise ratio (PSNR) for bitrates, as shown in FIG. 7. It may be a rate-distortion curve, which is not necessarily a rate-distortion curve, but may be various models represented by the bit rate and the maximum signal-to-noise ratio for the macroblock.

By encoding using such a rate-distortion model, it is possible to obtain excellent image quality while encoding below a predetermined bit amount. The rate control method is based on rate-distortion optimization using this rate-distortion model, and for convenience, corrects the rate-distortion model on a picture basis. The rate-distortion model can be corrected in units of macroblocks, but in this case there is much room for improvement in overall compression performance, but the complexity is increased, so as described above, it is usually necessary to correct in units of pictures or group of macroblocks. Correct in units of).

When the rate-distortion model is updated in units of macroblocks, the encoding controller 110 determines whether all macroblocks are encoded as in step S240, and if all macroblocks are not encoded, until all macroblocks are encoded. Steps S250 to S270 are performed on the remaining macroblocks, and when all macroblocks are encoded, the rate-distortion model is updated in picture units based on the updated rate-distortion model for all encoded macroblocks (S280). In operation S220, it is determined whether all encoding of all pictures of the video is completed (S220), and if encoding of all pictures is not completed, steps S230 to S1 of the remaining pictures are performed until encoding of all pictures is completed. After performing S280 and encoding of all the pictures is completed, the encoding ends.

Meanwhile, although FIG. 2 illustrates and described that both step S270 and step S280 are performed, according to the unit for updating the rate-distortion model, it may be performed only in macroblock units as in step S270 or only in picture units as in step S280. have.

Hereinafter, an apparatus and method for effectively performing multiple encoding by dividing a video into a plurality of encoding sections and setting and updating a rate-distortion model for each encoding section will be described with reference to the second embodiment.

3 is a block diagram schematically illustrating an apparatus for setting an encoding interval according to a third embodiment.

The encoding interval setting apparatus 300 according to the third embodiment includes a scaler 310, an encoder 320, a corrector 330, an interval setter 340, and a bit rate allocator. Allocator 350 may be configured. Here, the bit rate allocator is not necessarily included in the encoding interval setting apparatus 300 but may be selectively included according to an implementation method. Although the encoding interval setting apparatus 300 may be implemented as hardware or software independent of the image encoding apparatus 100 described above with reference to FIG. 1, the image encoding apparatus 100 or the image encoding apparatus described above with reference to FIG. It may be implemented as dependent hardware or software implemented within the coding controller 110 of 100.

The scaler 310 reduces the resolution of the image. That is, the scaler 310 downsamples the images constituting the moving image, that is, the pictures, at various ratios such as 2: 1 and 3: 1, and reduces the resolution of the image.

In this case, reducing the image using the scaler 310 requires a large amount of computation when encoding all the pictures of the video to the original size in order to divide the video into a plurality of encoding intervals, thereby increasing the complexity of the implementation and increasing the time delay. Since the efficiency is reduced, the size of the image is reduced to reduce the amount of computation required by the encoder 320 to be described later. The scaler 310 may determine whether to reduce the image according to a predetermined criterion. The predetermined criterion may be changed by the user or may be changed according to a separate criterion.

For example, the predetermined reference may be whether the size of the image is smaller than the size of the preset reference image when comparing the size of the image with the size of the preset reference image. In this case, the scaler 310 may have a size of the image. The resolution of the image may be reduced only when it is smaller than the set size of the reference image. In this case, the scaler 310 determines the number of macroblocks included in the image and the number of macroblocks included in the reference image when the aspect ratio of the image is different from the aspect ratio of the reference image. The size of the image and the size of the reference image may be compared, and the resolution of the image may be reduced so that the difference between the number of macroblocks included in the image and the number of macroblocks included in the reference image is equal to or less than a preset number. .

As another example, the predetermined standard may be a resolution of a used TV standard or a digital versatile disk (DVD) standard. If the predetermined standard is a resolution specified in a standard such as an analog TV or a DVD, the resolution of a picture of an input video is input. Is the maximum supported resolution of a high definition television (HDTV), an image having a resolution of 1920x10802 in width x length may be reduced in a ratio of 1/3 in width and height respectively.

The encoder 320 encodes an image having a reduced resolution to generate encoding result information about the reduced image. In addition, the encoder 320 encodes the unreduced image when the scaler 310 decides not to reduce the image. Here, the encoder 320 is a device that performs not only the function of the encoder 160 described above with reference to FIG. 1 but also the function of the image encoding apparatus 100 described with reference to FIG. 1. That is, the encoder 320 should be understood as a concept of performing prediction, transform, quantization, entropy encoding, and the like.

The corrector 330 corrects the encoding result information to generate encoding result information about the image. That is, when the encoder 320 encodes the reduced image, the corrector 330 corrects the result information generated during the encoding of the reduced image, that is, the encoding result information of the image before the encoding result information is reduced. To this end, the corrector 330 estimates the encoding result information of the image before the reduction based on the encoding result information of the reduced image using the frequency analysis result information of the image and the frequency analysis result information of the reduced image. This can be corrected. Here, the encoding result information may be, for example, one or more of a bit rate, an average square error, and an encoding parameter determined in an encoding process, which is a result of encoding.

The interval setter 340 sets a plurality of encoding intervals by analyzing encoding result information about the image. That is, the interval setter 340 is corrected for the image that has not been encoded result information of the reduced image transmitted from the encoder 320 or the encoding result information of the reduced image transmitted from the corrector 330. The video is set as a plurality of encoding sections based on the encoding result information. A group of portions having a rate-distortion cost or a difference between the rate-distortion model and each other in the image that is equal to or less than a preset value is set as the encoding section. Can be.

To this end, the interval setter 340 analyzes the encoding result information of the image, collects portions having similar rate-distortion cost or rate-distortion model into groups, and sets the collected groups as a plurality of encoding intervals. Accordingly, the coding section may be a section having a similar rate-distortion cost or rate-distortion model and may be a picture unit or a block unit such as a slice unit, a macroblock, or a subblock.

Here, the interval setter 340 may set a rate-distortion model for each of a plurality of coding intervals. Although it may be set as a distortion model, the rate-distortion model may be set for each section in various ways according to a predetermined criterion without being limited thereto.

The bit rate allocator 350 allocates a target bit rate for each of a plurality of encoding intervals according to a predetermined bit rate based on the bit rate and the mean square error included in the encoding result information of the image. That is, when a plurality of encoding intervals are set by the interval setter 340, the bit rate allocator 350 adjusts the rate-distortion model of the corresponding encoding interval, that is, the bit rate and the mean square error included in the encoding result information of the image. A target bit rate for each encoding section is allocated based on the target bit rate, and a target bit rate for each encoding section is allocated according to a target bit rate of a preset video.

4 is a flowchart illustrating a method of setting an encoding interval according to a second embodiment.

If an image is input (S410), the encoding interval setting apparatus 300 determines whether the size of the image is larger than the size of the reference image (S420), and if the size of the image is smaller than or equal to the size of the reference image, If it is determined that there is no need to reduce the size, the input image is encoded as it is (S422). If the size of the image is larger than the size of the reference image, the resolution of the image is reduced (S430) and the reduced image is encoded (S440). The encoding result information of the reduced image is corrected to the encoding result information of the image having the original size (S450).

In addition, the encoding section setting apparatus 300 analyzes the encoding result information on the image generated by encoding the image input in operation S422 or the encoding result information on the image generated by correcting the operation in S450. A coding section is set (S460), and a bit rate is set for each set coding section (S470). Here, step S470 is not necessarily to be performed, it may be selectively performed according to the implementation manner.

Meanwhile, each of the steps described above and illustrated above with reference to FIG. 4 is merely shown to explain a method of setting an encoding interval according to the second embodiment, and is limited to the order of each step indicated by an execution step of the method of setting an encoding interval. The order of some or all of the steps may not only be changed, but may be performed in parallel depending on the implementation manner.

5 is a block diagram schematically illustrating a video multiplexing device according to a third embodiment.

The image multiple encoding apparatus 500 according to the third embodiment may include an encoder Encoder 510 and an Updater 520. The image multiplexing apparatus 500 may be implemented in software that is read and executed by a computer apparatus or a computer apparatus such as the image encoding apparatus 100 described above with reference to FIG. 1.

The encoder 510 encodes an image set as a plurality of encoding sections according to a rate-distortion model set for each encoding section, and repeatedly encodes the encoded image until the encoding target of the encoded image satisfies the predetermined target encoding result. That is, when an image is input, the encoder 510 encodes each encoding section by using a plurality of encoding sections set in the image and a bit rate and an average squared error determined by a rate-distortion model set for each encoding section. When the encoding is completed, it is determined whether the encoding result generated during the encoding satisfies the predetermined target encoding result and it is repeatedly multi-encoded until it is satisfied.

Here, the encoder 510 is a device that performs not only the function of the encoder 160 described above with reference to FIG. 1 but also the function of the image encoding apparatus 100 described with reference to FIG. 1. Accordingly, the encoder 510 should be understood as a concept including functions of prediction, transformation, quantization, entropy encoding, and the like. In addition, multiple encoding means encoding an image multiple times, and means encoding the same image (or a picture or a sequence) two or more times.

In addition, the encoder 510 encodes a previously encoded image that has a bit rate and a maximum signal-to-noise ratio that are generated as a result of encoding the encoded image that are different from or below a predetermined target bit rate and a target maximum signal-to-noise ratio, respectively. If the resultant bit rate and the maximum signal-to-noise ratio differ from the preset value, it may be determined that the encoding result of the encoded image satisfies the predetermined target encoding result. That is, the encoder 510 achieves the preset target if the encoding result of the encoded image is similar to the target encoding result of the preset image or similar to the encoding result generated at the previous encoding, although it is not similar to the target encoding result of the preset image. It can be determined that the repetitive encoding is stopped.

The updater 520 updates the rate-distortion model set for each of the plurality of encoding sections according to the encoding result of the encoded image every time the image is set in the plurality of encoding sections. That is, the updater 520 analyzes the encoding result of the generated image every time the encoder 510 encodes an image set to a plurality of encoding sections, and updates the rate-distortion model set for each encoding section based on the analysis result. Update. Here, the updater 520 may update the rate-distortion model by using the bit rate and the mean squared error that are generated each time the image set to the plurality of encoding sections is encoded.

6 is a flowchart illustrating a video multiplexing method according to a third embodiment.

When an image is input, the image multiple encoding apparatus 500 encodes an image set as a plurality of encoding sections according to a rate-distortion model set for each encoding section (S610), and determines whether the encoding result of the image satisfies the target encoding result. If it is determined (S620) that the target encoding result is not satisfied, the rate-distortion model set for each section is updated according to the encoding result of the image generated for each section (S630). Steps S610 and S630 are repeatedly performed until it satisfies. If the determination result of step S620 during the repetition is performed, and the encoding result of the image satisfies the target encoding result, a bitstream of the encoded image is output (S640). .

Meanwhile, each of the above-described steps shown in FIG. 6 and the above-described steps are merely shown to explain the video multiplexing method according to the third embodiment, and the execution steps of the video multiplexing method are necessarily limited to the order of each step. The order of some or all of the steps may not only be changed, but may be performed in parallel depending on the implementation manner.

In addition, the video encoding method, the encoding interval setting method, and the image multiple encoding method described above with reference to FIGS. 2, 4, and 6 may be realized by an image encoding program, an encoding interval setting program, and an image multiple encoding program, respectively. Each program may be a memory provided in a computer such as the image encoding apparatus 100, the encoding interval setting apparatus 300, and the image multiplex encoding apparatus 500, as described above with reference to FIGS. 1, 3, and 5. It is stored on a record carrier and can be read and executed by a computer.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments. In other words, within the scope of the present invention, all of the components may be selectively operated in combination with one or more. In addition, although all of the components may be implemented as one independent hardware, some or all of the components may be selectively combined to perform a part or all of the functions in one or a plurality of hardware. As shown in FIG. Codes and code segments constituting the computer program may be easily inferred by those skilled in the art. Such a computer program may be stored in a computer readable storage medium and read and executed by a computer, thereby implementing embodiments of the present invention. As the storage medium of the computer program, a magnetic recording medium, an optical recording medium, a carrier wave medium, or the like may be included.

Furthermore, the terms "comprises", "comprising", or "having" described above mean that a component can be implanted unless otherwise specifically stated, But should be construed as including other elements. All terms, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, unless otherwise defined. Terms used generally, such as terms defined in a dictionary, should be interpreted to coincide with the contextual meaning of the related art, and shall not be interpreted in an ideal or excessively formal sense unless explicitly defined in the present invention.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

As described above, the present invention is applied to an image processing field for compressing a moving image, while dividing an image into a plurality of encoding sections and setting and updating a rate-distortion model for each section, while encoding using a more suitable rate-distortion model. It is a very useful invention that can simplify the update of the rate-distortion model and generate the effect of improving the coding efficiency by multi-coding the image using the rate-distortion model set and updated for each section.

1 is a block diagram schematically illustrating a video encoding apparatus according to a first embodiment;

2 is a flowchart illustrating a video encoding method according to a first embodiment;

3 is a block diagram schematically illustrating an apparatus for setting an encoding interval according to a third embodiment;

4 is a flowchart for explaining a coding interval setting method according to a second embodiment;

5 is a block diagram schematically illustrating a video multiplexing device according to a third embodiment;

6 is a flowchart for explaining a video multiple encoding method according to a third embodiment;

7 is an exemplary view showing a rate-distortion model.

Description of the Related Art

310: scaler 320: encoder

330: compensator 340: interval setter

350: bit rate allocator 520: updater

Claims (17)

In the apparatus for setting a video to a plurality of coding intervals, A scaler for reducing the resolution of the image; An encoder for encoding the reduced-resolution image to generate encoding result information about the reduced image; A corrector for correcting the encoding result information to generate encoding result information for the image; And An interval setter configured to set the plurality of encoding intervals by analyzing encoding result information about the image Encoding interval setting apparatus comprising a. The method of claim 1, wherein the scaler, And the resolution of the image is reduced only when the size of the image is smaller than the size of a preset reference image. The method of claim 2, wherein the scaler, If the aspect ratio with respect to the size of the image is different from the aspect ratio with respect to the size of the reference image, the number of macroblocks included in the image and the number of macroblocks included in the reference image are compared. And a magnitude comparison with a magnitude of the reference image. The method of claim 1, wherein the scaler, If the aspect ratio for the size of the image and the aspect ratio for the size of the reference image are different, the difference between the number of macroblocks included in the image and the number of macroblocks included in the reference image is less than or equal to a preset number. And encoding resolution of the video to be reduced. The method of claim 1, wherein the corrector, Correcting by estimating encoding result information of the image based on the encoding result information of the reduced image using the frequency analysis result information of the image and the frequency analysis result information of the reduced image. Encoding interval setting device. The method of claim 1, wherein the section setter, And a group of portions in which the difference in the rate-distortion cost between the images is less than or equal to a preset value as the encoding section. The method of claim 1, wherein the section setter, And a rate-distortion model for each of the plurality of encoding sections. The method of claim 7, wherein the rate-distortion model, And a rate-distortion curve expressed by a maximum signal-to-noise ratio with respect to the bit rate. The method of claim 1, wherein the encoding result information about the video is And a coding parameter determined in the encoding process. The apparatus of claim 1, wherein the encoding interval setting apparatus is performed. And a bit rate allocator for allocating a target bit rate for each of the plurality of encoding intervals according to a preset bit rate based on the bit rate and the mean square error included in the encoding result information of the image. Device. In the method for setting a video to a plurality of coding intervals, Reducing the resolution of the image; An encoding step of encoding the reduced resolution image to generate encoding result information about the reduced image; A correction step of generating encoding result information of the image by correcting the encoding result information; And An interval setting step of setting the plurality of encoding intervals by analyzing encoding result information about the image Encoding interval setting method comprising a. In the apparatus for multi-encoding video, An encoder which encodes an image configured as a plurality of encoding intervals according to a rate-distortion model set for each encoding interval, and repeatedly encodes an encoding result of the encoded image until a predetermined target encoding result is satisfied; And An updater for updating a rate-distortion model set for each of the plurality of encoding sections according to an encoding result of the encoded image every time the images configured for the plurality of encoding sections are encoded. Video encoding apparatus, characterized in that it comprises a. The method of claim 12, wherein the encoder, If the bit rate and the maximum signal-to-noise ratio generated as the encoding result of the encoded image differ from each other by less than the preset target bit rate and the target maximum signal-to-noise ratio, respectively, the encoding result of the encoded image is the predetermined target. And a video encoding apparatus characterized in that it is determined to satisfy an encoding result. The method of claim 12, wherein the encoder, If the bit rate and the maximum signal-to-noise ratio generated as the encoding result of the encoded image differ from the bit rate and the maximum signal-to-noise ratio generated as the encoding result of the previous encoded image, respectively, below the predetermined value, And determining that an encoding result satisfies the predetermined target encoding result. The method of claim 12, wherein the updater, And the rate-distortion model is updated by using a bit rate and an average squared error that are generated each time the image set to the plurality of encoding intervals is encoded. In the method of multi-encoding the video, An encoding step of encoding an image set with a plurality of encoding sections according to a rate-distortion model set for each encoding section; A determination step of determining whether an encoding result of the encoded image satisfies a predetermined target encoding result; An update step of updating a rate-distortion model set for each of the plurality of encoding sections according to an encoding result of the encoded image when the encoding result of the encoded image does not satisfy a preset target encoding result; And An output step of outputting a bitstream of the encoded image when the encoding result of the encoded image satisfies the preset target encoding result. Image multiple encoding method comprising a. A computer-readable recording medium having recorded thereon a program for realizing the method of any one of claims 11 and 16.

Images