KR100956641B1 - Video encoding method and apparatus, video decoding method and apparatus, and computer-readable storage medium - Google Patents

Abstract

The present invention relates to an image encoding apparatus, an image encoding method, an image decoding apparatus, an image decoding method, and a computer-readable recording medium. According to an aspect of the present invention, an image encoding apparatus includes: a first image frame input in a first mode; Rotates a predetermined angle to output the second image frame and the rotation unit and the second image frame are divided into a top field and a bottom field by an interlace method, and the top field and the bottom field are divided. And an encoder which encodes the second image frame by using the encoder.

H.264, binocular video

Description

An image encoding apparatus, an image encoding method, an image decoding apparatus, an image decoding method, and a computer-readable recording medium {Video encoding method and apparatus, video decoding method and apparatus, and computer-readable storage medium}

The present invention relates to an image encoding apparatus, an image encoding method, an image decoding apparatus, an image decoding method, and a computer-readable recording medium. The present invention relates to an image encoding apparatus capable of encoding or decoding a binocular image in various formats, an image encoding method, and an image decoding. An apparatus, an image decoding method, and a computer readable recording medium.

H.264 / MPEG-4 AVC, a joint international standard of ISO / IEC and ITU-T, supports binocular video encoding through the supplemental enhancement information (SEI) called stereo_video_info (). This SEI supports two methods of encoding. The first is a case where the format of the input image is a combination of the pixel rows of the left image and the pixel rows of the right image, and the second is the input image format of the left image and the right image. This is the case in which each is listed in picture units.

Specifically, in the first case, it may be encoded by using a MB-AFF (Macroblock-based Adaptive Field / Frame) method or a Pic-AFF (Picture-based Adaptive Field / Frame) method, and the MB-AFF (Macroblock-based Adaptive Field / Frame) method. The frame method is to divide an image frame into a top field and a bottom field in an interlaced manner, and encode the top field and the bottom field or the image frame in units of macroblocks. Pic-AFF The Picture-based Adaptive Field / Frame method encodes a top field and a bottom field or an image frame in picture units.

In the second case, since the left image and the right image are each arranged side by side in one picture, and then encoded, the frame rate of the image is doubled. That is, encoding a binocular image of 30 fps (frame per second) becomes the same as encoding a 60 fps single-eye image.

On the other hand, when encoding and decoding both eyes in H.264 / AVC, the compression efficiency varies according to the format of the image frame as described above. In addition, the above-mentioned format is not supported by H.264 / AVC. Therefore, there is a need for a technique capable of efficiently encoding and decoding image frames of various formats while using an encoder and decoder of a conventional H.264 / AVC method.

An object of the present invention is to provide an image encoding / decoding apparatus capable of efficiently compressing image frames of various formats while still using a conventional H.264 / AVC type encoder and decoder.

Another object of the present invention is to provide a video encoding / decoding method capable of efficiently compressing video frames of various formats while still using a conventional H.264 / AVC type encoder and decoder.

It is still another object of the present invention to provide a computer-readable recording medium storing messages used for efficiently compressing image frames of various formats while still using a conventional H.264 / AVC type encoder and decoder. It is.

The object of the present invention is not limited to the above-mentioned object, and other objects that are not mentioned will be clearly understood by those skilled in the art from the following description.

According to an aspect of the present invention, there is provided an apparatus for encoding an image. The image encoding apparatus may include a rotation unit and a second image frame configured to rotate an input first image frame by a predetermined angle and output the second image frame. And an encoder configured to classify the second image frame by using a top field and a bottom field by using an interlace method, and using the top field and the bottom field.

The image encoding method according to an aspect of the present invention may include outputting a first image frame as a second image frame, rotating the first image frame by a predetermined angle in a first mode, and outputting the first image frame as the second image frame. And dividing the second image frame into a top field and a bottom field by an interlace method, and encoding the second image frame by using the top field and the bottom field. It includes a step.

Also, an image decoding apparatus according to another aspect of the present invention is provided with a decoder that decodes an encoded video sequence to reconstruct a first image frame, and a rotation flag indicating whether to rotate, and optionally according to the rotation flag. And a rotation unit configured to rotate the first image frame by a predetermined angle and output the second image frame.

In addition, the image decoding method according to another aspect of the present invention, decoding the encoded video sequence to restore the first image frame, receiving a rotation flag indicating whether or not to rotate and the rotation flag And optionally rotating the first image frame by a predetermined angle to output the second image frame.

Further, in a computer-readable recording medium storing a message required to decode a video sequence encoded by an image frame according to another aspect of the present invention, the message is rotated to indicate whether the image frame is rotated and encoded. And a message including a flag and a rotation direction flag indicating a rotation direction of the image frame when the image frame is rotated.

Specific details of other embodiments are included in the detailed description and the drawings.

According to the present invention, binocular images of various formats can be efficiently encoded and decoded.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various different forms, and only the embodiments make the disclosure of the present invention complete, and the general knowledge in the art to which the present invention belongs. It is provided to fully inform the person having the scope of the invention, which is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

Hereinafter, an image encoding apparatus, an image encoding method, an image decoding apparatus, an image decoding method, and a computer readable recording medium according to an embodiment of the present invention will be described with reference to FIGS. 1A to 5. The explanation focuses on the parts necessary to understand the operation.

First, before describing an embodiment of the present invention, the type of the binocular image format will be described with reference to FIGS. 1A to 1C. FIG. 1A is a schematic diagram for capturing a binocular image, FIG. 1B is a conceptual diagram for describing a binocular image frame of a first format, and FIG. 1C is a conceptual diagram for describing a binocular image frame of a second format.

Referring to FIG. 1A, two cameras c1 and c2 photograph one subject S to form a binocular image. For example, the first camera c1 captures an image of the left side of the subject S, and the second camera c2 captures an image of the right side of the subject S. FIG.

FIG. 1B shows a left image TF taken by the first camera c1, a right image BF taken by the second camera c2, and an image frame FRM1 having a first format composed therefrom. have. Hereinafter, an example in which the left image TF and the right image BF constitute one field field fileld will be described as an example. However, the left image TF and the right image BF may each be one frame. The size may vary depending on the resolution of each of the cameras c1 and c2.

Each field TF and BF may include a plurality of pixels, and each field TF and BF may be divided into a plurality of pixel columns. The image frame FRM1 of the first format illustrated in FIG. 1B may be a format in which pixel columns of the first field TF and the second field BF are sequentially and alternately combined. However, the image frame FRM1 of the first format is not limited thereto, and the odd (or even) pixel columns of the pixel columns of the first field TF and the even (or odd) pixel columns of the second field BF, respectively, are not limited thereto. In sequential order, it may be a format combined alternately. That is, the image frame FRM1 of the first format may be a format in which pixel columns of at least one first field TF and pixel columns of at least one second field BF are sequentially and alternately combined. . Hereinafter, a case in which all pixel columns of the first field TF and the second field BF are in a format in which they are sequentially and alternately combined will be described as an example.

FIG. 1C shows a first field TF taken by the first camera c1, a second field BF taken by the second camera c2, and a second format having a different format from that shown in FIG. 1B. An image frame FRM2 is shown.

Specifically, each field TF and BF may include a plurality of pixels, and each field TF and BF may be divided into pixel rows. The second image frame FRM2 illustrated in FIG. 1C may have a format in which pixel rows of the first field BF and the second field BF are sequentially and alternately combined. However, the image frame FRM2 of the second format is not limited thereto, and the odd (or even) pixel rows of the first field TF and the even (or odd) pixel rows of the second field BF are sequentially arranged. It may be a format combined alternately. That is, the image frame FRM2 of the second format may be a format in which pixel rows of at least one first field TF and pixel rows of at least one second field BF are sequentially and alternately combined. have. Hereinafter, a case in which all pixel rows of the first field TF and the second field BF are in a format in which they are sequentially and alternately combined will be described as an example.

As described above, in the binocular image, image frames FRM1 and FRM2 of the formats shown in FIGS. 1B and 1C may be configured from fields captured by two cameras c1 and c2. The image encoding apparatus 100, the image encoding method, the image decoding apparatus 200, and the image decoding method efficiently encode / encode the image frame FRM1 and FRM2 formats of the first and second formats shown in FIGS. 1B and 1C. Can be decrypted Hereinafter, the present invention will be described in detail with reference to FIGS. 2 to 5.

First, an image encoding / decoding apparatus and method for encoding / decoding an image frame FRM1 of the first format shown in FIG. 1B will be described with reference to FIGS. 2A to 3. FIG. 2A is a block diagram illustrating an image encoding apparatus according to an exemplary embodiment of the present invention, FIG. 2B is a conceptual diagram illustrating a first rotation unit and an encoding unit of FIG. 2A, and FIG. 3 is an image decoding apparatus according to an embodiment of the present invention. A block diagram showing a device.

Referring to FIG. 2A, the image encoding apparatus 100 includes a first rotation unit 110 and an encoder 120.

In detail, when the image frame FRM1 of the first format is input (first mode), the first rotation unit 110 rotates the input image frame FRM1 by a predetermined angle, for example, 90 °. Output to 120. At this time, the first rotation unit 110 displays a rotation flag (frm_rotate_flag) indicating whether the input image frame FRM1 is rotated and a rotation direction flag (is_right90_flag) indicating the rotation direction of the image frame FRM1. A message containing the message may be output. For example, when the image frame FRM1 of the first format is input (first mode), the first rotation unit 110 rotates the image frame FRM1 of the first format, and thus the first rotation unit 110. ) May generate and output a rotation flag (frm_rotate_flag) of “1”.

Also, when the first rotation unit 110 rotates the image frame FRM1 of the first format by 90 ° clockwise, that is, + 90 °, the first rotation unit 110 rotates in the direction of “1”. When the flag is_right90_flag may be generated and output, or when the image frame FRM1 of the first format is rotated 90 degrees counterclockwise, that is, rotated by -90 degrees, the first rotation unit 110 may be “ 0 ”rotation direction flag is_right90_flag may be generated and output. The message including the rotation flag (frm_rotate_flag) and the rotation direction flag (is_right90_flag) is provided to the second rotation unit 210 of the image decoding apparatus 200 to be described later through the encoder 120. However, the first rotation unit 110 is not limited to 90 degrees according to the format of the image frame FRM1, and may be rotated by another predetermined angle.

The encoder 120 encodes the rotated image frame FRM1 and transmits the encoded bitstream (or video sequence) to the image decoding apparatus 200. Here, the encoder 120 may encode the image frame FRM1 rotated by 90 degrees by using the H.264 standard method.

In detail, as illustrated in FIG. 2B, the encoder 120 receives an image frame FRM1_90 rotated by 90 ° from the first rotation unit 110, and interlaces the top field TF_90 by an interlaced method. The image frame FRM1_90 rotated by 90 ° is encoded using the top field TF_90 and the bottom field BF_90. Here, the top field TF-90 may be rotated 90 ° of the first field TF shown in FIG. 2B. That is, in the top field TF_90, the left image TF of the subject S may be rotated 90 °. Similarly, in the bottom field BF_90, the second field BF is rotated by 90 °, and the right image BF of the subject S may be rotated by 90 °.

For example, the encoder 120 encodes in a 16 × 32 block unit including 16 × 16 macroblocks of the top field TF_90 and 16 × 16 macroblocks of the bottom field BF_90, and rotates 90 °. Coded data having a high compression efficiency can be selected from among the 16 × 32 (or 16 × 16) block units of the video frame FRM1_90 (MB-AFF). Alternatively, the encoder 120 encodes the image frame FRM1_90 rotated by 90 ° in picture (or frame) unit, and encodes in picture (or frame) unit by attaching the top field TF_90 and the bottom field BF_90. Among them, coded data having a high compression efficiency can be selected (Pic-AFF). In addition, the encoder 120 may perform a motion compensation process using a motion estimation process, a transform process such as a discrete cosine transform (DCT), and a quantization process. Also, the encoder 120 may use a ratio of 4: 2: 0 or 4: 2: 2 between the luminance Y, the color difference Cb, and the sampling frequency of the Cr signal.

Also, the encoder 120 may encode a message including a rotation flag (frm_rotate_flag) and a rotation direction flag (is_right90_flag) together.

Meanwhile, since the technical idea of the present invention is to rotate and encode the image frame FRM1 of the first format into the image frame FRM1_90 interlaced in the horizontal (or horizontal) direction as illustrated in FIG. 2B, the encoder 120 ) Is a method of encoding the image frame FRM1_90 rotated by 90 °. The method is not limited to any one, and may be any known method, and may be any one of methods developed later. Therefore, the present specification is not limited to any one method.

Next, referring to FIG. 3, the image decoding apparatus 200 includes a decoder 220 and a second rotation unit 210.

In detail, the decoder 220 receives an encoded bitstream (or a video sequence) from the encoder 120 and decodes the encoded bitstream. For example, the decoder 220 is a unit corresponding to the encoder 120 and the image frame rotated 90 degrees in a manner corresponding to the method in which the encoder 120 encodes the image frame FRM1_90 rotated 90 degrees. Decode to restore (FRM1_90). That is, the decoder 220 may reconstruct the 90 ° rotated image frame FRM1_90 by decoding the encoded top field and the bottom field. However, in the present invention, since the method of encoding by the encoder 120 is not limited to any one, the method of decoding by the decoder 220 is not limited to any one.

In addition, the decoder 220 extracts a message including a rotation flag (frm_rotate_flag) and a rotation direction flag (is_right90_flag) while decoding the bitstream and provides the message to the second rotation unit 210.

When the rotation flag (frm_rotate_flag) is "1", the second rotation unit 210 rotates the image frame FRM1_90 output from the decoder 220 according to the rotation direction flag is_right90_flag. For example, when the rotation flag (frm_rotate_flag) is "1" and the rotation direction flag (is_right90_flag) is "1", the second rotation unit 210 outputs an image frame FRM1_90 output from the decoder 220. Is rotated counterclockwise, that is, -90 ° to output the image frame FRM1 of the first format. Alternatively, when the rotation flag (frm_rotate_flag) is "1" and the rotation direction flag (is_right90_flag) is "0", the second rotation unit 210 clocks the image frame FRM1_90 output from the decoder 220. That is, the image frame FRM1 of the first format is output by rotating + 90 °. If the rotation flag (frm_rotate_flag) is "0", the image frame output from the decoder 220 is output without rotating, regardless of the rotation direction flag (is_right90_flag). This case will be described later with reference to FIGS. 4A to 5.

According to the exemplary embodiment of the present invention, the binocular image frame FRM1 of the first format illustrated in FIG. 1B may be efficiently encoded. In addition, in the image encoding apparatus 100 according to an exemplary embodiment of the present invention, the encoder 120 uses a conventional H.264 / AVC standard scheme to display an image frame FRM1 of the first format shown in FIG. 1B. Can be efficiently encoded. Specifically, a technique for efficiently encoding the 90 [deg.] Rotated image frame FRM1_90 shown in FIG. 2B has already been developed. The H.264 / AVC standard also efficiently encodes such an image format. In the case of compressing the binocular image frame FRM1 of the illustrated first format, a large amount of loss occurs in terms of efficiency. That is, when the binocular image frame FRM1 of the first format shown in FIG. 1B is rotated by 90 °, converted into an image of the format as shown in FIG. 2B, and encoded, a conventionally developed encoding tool and a method for executing the same. Compression efficiency can be increased without changing hardware.

Meanwhile, a message including the rotation flag (frm_rotate_flag) and the rotation direction flag (is_right90_flag) will be described in detail below. A message including the rotation flag (frm_rotate_flag) and the rotation direction flag (is_right90_flag) may have the following syntax.

ext_stereo_video_info (payloadSize) { Descriptor    frm_rotate_flag u (1)    if (frm_rotate_flag) {         Is_right90_flag u (1)    } }

The message ext_stereo_video_info includes a rotation flag (frm_rotate_flag) and a rotation direction flag (is_right90_flag). As described above, the rotation flag (frm_rotate_flag) is, for example, 1 bit, and the input image frame FRM1_90 is rotated. Is a flag for notifying, and the rotation direction flag (is_right90_flag) is, for example, 1 bit and is a flag for notifying the rotation direction of the video frame FRM1_90.

When the first rotation unit 110 transmits the rotation flag (frm_rotate_flag) and the rotation direction flag (is_right90_flag) according to the rotation and the rotation direction, the second rotation unit 210 transmits the decoded image frame FRM1_90 accordingly. It rotates again and restores the image frame FRM1 that was finally input.

Next, referring to FIGS. 4A to 5, when the image frame FRM2 of the second format illustrated in FIG. 1C is input (second mode), the image frame FRM2 of the second format is encoded / decoded. A video encoding / decoding apparatus and method will be described. FIG. 4A is a block diagram illustrating an image encoding apparatus according to another embodiment of the present invention. FIG. 4B is a conceptual diagram for describing the first rotation unit and the encoding unit of FIG. 4A, and FIG. 5 is a view illustrating another embodiment of the present invention. Fig. 1 is a block diagram showing a video decoding apparatus.

Referring to FIG. 4A, when the image frame FRM2 of the second format is input (second mode), the first rotation unit 110 does not rotate the input image frame FRM2 by 90 ° without changing the encoder ( 120). At this time, the first rotation unit 110 may output a message including a "0" rotation flag (frm_rotate_flag) indicating that the input image frame FRM2 is not rotated. The message including the rotation flag (frm_rotate_flag) is provided to the second rotation unit 210 of the image decoding apparatus 200 described later through the encoder 120.

The encoder 120 encodes the image frame FRM2 output from the first rotation unit 110, and transmits the encoded bitstream to the image decoding apparatus 200. Here, the encoder 120 may encode the video frame FRM2 by, for example, the H.264 / AVC standard method.

Specifically, as illustrated in FIG. 4B, the encoder 120 receives the image frame FRM2 from the first rotation unit 110, and uses the interlaced top field TF and the bottom field BF. ) And encodes an image frame FRM2 using the top field TF and the bottom field BF. Here, the top field TF is the first field TF illustrated in FIG. 1C, which may be a left image of the subject S, and the bottom field BF is the second field TF, which is a representation of the subject S. It may be a right image.

For example, the encoder 120 encodes a 16 × 32 block unit including 16 × 16 macroblocks of the top field TF and 16 × 16 macroblocks of the bottom field BF, and encodes an image frame ( Coded data having a high compression efficiency can be selected from among the 16 × 32 (or 16 × 16) block units of the FRM2 (MB-AFF). Alternatively, as described above, the encoder 120 may encode the Pic-AFF scheme. In addition, the encoder 120 may perform a motion compensation process using a motion estimation process, a transform process such as a discrete cosine transform (DCT), and a quantization process. Also, the encoder 120 may use a ratio of 4: 2: 0 or 4: 2: 2 between the luminance Y, the color difference Cb, and the sampling frequency of the Cr signal.

In addition, the encoder 120 may encode a message including a rotation flag (frm_rotate_flag) together. Meanwhile, the encoding unit 120 may encode the second frame of the image frame FRM2 by any method known in the art, and may be any one of methods developed thereafter.

Next, referring to FIG. 5, the decoder 220 receives a bitstream from the encoder 120 and decodes the bitstream. For example, the decoder 220 is a unit corresponding to the encoder 120, and the image frame of the second format encoded according to the method in which the encoder 120 encodes the image frame FRM2 of the second format. Decrypt to restore (FRM2). That is, the decoder 220 may decode the encoded top field TF and the bottom field BF to restore the image frame FRM2 of the second format.

In addition, the decoder 220 extracts a message including the rotation flag (frm_rotate_flag) while decoding the bitstream and provides the message to the second rotation unit 210.

Since the rotation flag (frm_rotate_flag) is “0”, the second rotation unit 210 outputs the image frame FRM1 output from the decoder 220 without being rotated. In this case, the second rotation unit 210 may ignore the rotation direction flag is_right90_flag. For example, if the rotation flag (frm_rotate_flag) is "0", regardless of whether the rotation direction flag (is_right90_flag) is "1" or "0", the second rotation unit 210 is output from the decoder 220. The video frame FRM2 is output without being rotated.

According to the exemplary embodiment of the present invention, even when the binocular image frames FRM1 and FRM2 of any of the first and second formats of the binocular image frames FRM1 and FRM2 shown in FIGS. 1B and 1C are inputted, The binocular image frames FRM1 and FRM2 can be encoded efficiently. Further, even when the binocular image frames FRM1 and FRM2 of any format are input from the first and second format binocular image frames FRM1 and FRM2 shown in Figs. 1B and 1C, conventionally known H.264 Can be encoded efficiently by the / AVC standard method.

Meanwhile, according to another embodiment, when the input image frames FRM1 and FRM2 are limited to the case of the first format shown in FIG. 1B, the rotation flag (frm_rotate_flag) and the rotation direction flag (is_right90_flag) according to the present invention. The message containing) may be removed. That is, the first rotation unit 110 may always rotate the input image frame FRM1 to + 90 °, and the second rotation unit 210 may always rotate the decoded image frame FRM1_90 to -90 °. have. Alternatively, only the rotation flag (frm_rotate_flag) may be removed. That is, when the first rotation unit 110 rotates the input image frame FRM1_90 to + 90 ° or -90 ° and transmits the rotation direction flag is_right90_flag accordingly, the second rotation unit 210 According to the rotation direction flag is_right90_flag, the decoded image frame FRM1_90 may be rotated by -90 ° or + 90 °.

Next, an image encoding method according to another embodiment of the present invention will be described with reference to FIG. 6. 6 is a flowchart illustrating an image encoding method according to another embodiment of the present invention.

Referring to FIG. 6, the input image frame is rotated 90 ° (S610). In this case, a rotation flag indicating whether the image frame is rotated and / or a rotation direction flag indicating the rotation direction may be output. However, as described above, when the input image frame is limited to the image frame FRM1 of the first format shown in FIG. 1B, the rotation flag and the rotation direction flag may not be output. Alternatively, only the rotation direction flag may be output.

Next, the image frame rotated by 90 ° is encoded (S620). In this case, an image frame rotated by 90 ° may be encoded by the H.265 / AVC standard method. In addition, the rotation flag and / or the rotation direction flag may be encoded together.

An image decoding method according to an embodiment of the present invention will be described with reference to FIG. 7. 7 is a flowchart illustrating an image decoding method according to an embodiment of the present invention.

Referring to FIG. 7, an encoded video frame is decoded (S710). Here it can be decoded in a manner according to the H.265 / AVC standard.

Next, the decoded video frame is rotated 90 ° (S720). The rotation flag may be rotated with reference to the rotation flag and / or the rotation direction flag. That is, if the rotation flag indicates rotation, the decoded image frame may be rotated according to the rotation direction indicated by the rotation direction flag. However, as described above, when the video frame to be encoded is limited to the video frame FRM1 of the first format shown in FIG. 1B, the decoding of the decoded video frame without reference to the rotation flag and the rotation direction flag are performed. It can be rotated 90 ° as opposed to the direction of rotation. Alternatively, it may be rotated by 90 ° with reference only to the rotation direction flag.

Hereinafter, an image encoding apparatus, an image encoding method, an image decoding apparatus, an image decoding method, and a computer readable recording medium according to another embodiment of the present invention will be described with reference to FIG. 8. 8 is a block diagram illustrating a video encoding apparatus according to another embodiment of the present invention.

First, in this embodiment, a message ext_stereo_video_info necessary to decode a bitstream (or a video sequence) encoded with an image frame may be as follows.

ext_stereo_video_info (payloadSize) { Descriptor    frm_rotate_flag u (1)    if (frm_rotate_flag) {         Is_right90_flag u (1)    }    stero_video_info () }

That is, the message ext_stereo_video_info may further include stero_video_info, which is a stereo video information SEI defined by the H.264 / AVC standard, in addition to the rotation flag (frm_rotate_flag) and the rotation direction flag (is_right90_flag).

Stero_video_info, which is a stereo video information SEI, is a message instructing the encoder 120 that a pair of coded video sequences form a binocular image in the H.264 / AVC standard. It is defined. The stero_video_info, which is a stereo video information SEI, is as follows.

stereo_video_info (payloadSize) { Descriptor    field_view_flag u (1)    if (field_view_flag)         top_field_is_left_view_flag u (1)    else {         current_frame_is_left_view_flag u (1)         next_frame_is_second_view_flag u (1)    } left_view_self_contained_flag u (1) right_view_self_contained_flag u (1) }

In this case, the format of the input image frame is not a combination of pixel columns (or pixel rows) of the left image and the right image, and as shown in FIG. 8, the frame (or picture) of the left image (FRM3_L) Even when frames (or pictures) FRM3_R of the right and right images are listed and sequentially input (third mode), the image can be efficiently encoded and decoded.

That is, among the image frame FRM1 of the first format shown in FIG. 1B, the image frame FRM2 of the second format shown in FIG. 1C, and the image frames FRM3_L and FRM3_R of the third format shown in FIG. 8. Whatever the format of the image frame, the image can be efficiently encoded and decoded. More specifically, according to the format of the input image, the first rotation unit 110 rotates the image frame in the first mode, and the encoder 120 without rotating the image frame in the second and third modes. To provide. In addition, the first rotation unit 110 outputs a message ext_stereo_video_info. The encoder 120 efficiently encodes the image frame output from the first rotation 110 and outputs the encoded bitstream. The decoder 210 receives and decodes the bitstream, and the second rotation unit 220 selectively rotates the image frame output from the decoder 210 with reference to the message ext_stereo_video_info. That is, the second rotation unit 220 rotates and outputs the image frame output from the decoder 210 in the first mode, and outputs the same without being rotated in the second and third modes.

Those skilled in the art will appreciate that the present invention can be embodied in other specific forms without changing the technical spirit or essential features of the present invention. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of the present invention is indicated by the scope of the following claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and the equivalent concept are included in the scope of the present invention. Should be interpreted.

1A is a block diagram for capturing a binocular image.

1B is a conceptual diagram illustrating a binocular image frame of a first format.

1C is a conceptual diagram illustrating a binocular image frame of a second format.

2A is a block diagram illustrating an image encoding apparatus according to an embodiment of the present invention.

FIG. 2B is a conceptual diagram illustrating the first rotation unit and the encoder of FIG. 2A.

3 is a block diagram illustrating an image decoding apparatus according to an embodiment of the present invention.

4A is a block diagram illustrating an image encoding apparatus, according to another embodiment of the present invention.

FIG. 4B is a conceptual diagram for describing the first rotation unit and the encoder of FIG. 4A.

5 is a block diagram illustrating an image decoding apparatus according to another embodiment of the present invention.

6 is a flowchart illustrating an image encoding method according to another embodiment of the present invention.

7 is a flowchart illustrating an image decoding method according to another embodiment of the present invention.

8 is a block diagram illustrating an image encoding apparatus according to another embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

100: video encoding apparatus 110: first rotation unit

120: encoder 200: video decoding device

210: second rotation unit 220: decoder

Claims (22)

A rotation unit configured to rotate the input first image frame by a predetermined angle and output the second image frame in a first mode; And An encoder configured to classify the second image frame into a top field and a bottom field by an interlace method, and to encode the second image frame by using the top field and the bottom field. Image encoding apparatus comprising. The method of claim 1, And the rotation unit provides a rotation direction flag indicating a rotation direction of the first image frame. The method of claim 1, wherein the first image frame in the first mode And at least one column of pixels constituting the left image of the subject and at least one column of pixels constituting the right image of the subject. The method of claim 1, In the second mode, the rotation unit is provided to the second image frame without rotating the first image frame. The method of claim 4, wherein And the rotation unit provides a rotation flag indicating whether or not the first image frame has been rotated. The method of claim 4, wherein the first image frame in the second mode And an at least one pixel row constituting the left image of the subject and at least one pixel row constituting the right image of the subject. The method of claim 1, And the encoder is configured to encode the second image frame according to the H.264 / AVC standard. Outputting a first image frame as a second image frame, wherein the first image frame is rotated by a predetermined angle in a first mode and outputted as the second image frame; And Dividing the second image frame into a top field and a bottom field by an interlace method, and encoding the second image frame by using the top field and the bottom field. Image coding method comprising. The method of claim 8, The outputting may include providing a rotation direction flag indicating a rotation direction of the first image frame. The method of claim 8, wherein the first image frame in the first mode And at least one column of pixels constituting the left image of the subject and at least one column of pixels constituting the right image of the subject. The method of claim 8, In the second mode, the outputting of the image encoding method outputs the second image frame without rotating the first image frame. The method of claim 11, The outputting may include providing a rotation flag indicating whether or not the first image frame has been rotated. The method of claim 11, wherein the first image frame in the second mode And an at least one pixel row constituting the left image of the subject and at least one pixel row constituting the right image of the subject in turn. The method of claim 8, And the encoding comprises encoding the second image frame according to the H.264 / AVC standard. A decoder configured to decode the encoded video sequence to reconstruct the first image frame; And And a rotation unit configured to receive a rotation flag indicating whether to rotate and selectively rotate the first image frame by a predetermined angle according to the rotation flag to output a second image frame. The method of claim 15, wherein the rotation unit Provided with a rotation direction flag indicating the direction of rotation, And rotating the first image frame by 90 ° according to the rotation direction when the rotation flag indicates rotation. Reconstructing the first image frame by decoding the encoded video sequence; Receiving a rotation flag indicating whether to rotate; And And selectively rotating the first image frame by a predetermined angle and outputting the second image frame according to the rotation flag. The method of claim 17, wherein the receiving step And receiving a rotation direction flag indicating a rotation direction. The method of claim 18, And when the rotation flag indicates rotation, the outputting includes rotating the first image frame by 90 ° corresponding to the rotation direction of the rotation direction flag. The method of claim 18, And when the rotation flag does not indicate rotation, outputting the output image comprises outputting the first image frame without rotating the image regardless of the rotation direction flag. A computer-readable recording medium storing a program for decoding a video sequence encoded with an image frame, the method comprising: The program is to perform decryption using a message, The message is A rotation flag indicating whether the image frame is rotated and encoded; And And a rotation direction flag indicating a rotation direction of the image frame when the image frame is rotated. Computer-readable recording medium having stored thereon program. The method of claim 21, The message further includes a stereo video information SEI of the H.264 / AVC standard. Computer-readable recording medium having stored thereon program.

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