JP2017158173A - Moving picture encoding device and moving picture encoding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a moving picture encoding device capable of efficiently encoding a moving picture having an interlaced structure.SOLUTION: A moving picture encoding device 100 encodes a moving picture having an interlaced structure, and includes a storage unit 120 in which plural fields are stored as plural reference pictures, and an encoding unit 110 for encoding an encoding target field as a B picture by using a first reference picture list including only one field in phase with the encoding target field out of plural fields, and a second reference picture list including only one field having a phase opposite to the encoding target field out of the plural fields.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a moving image encoding apparatus that encodes an interlaced moving image.

  Patent Document 1 relates to an image processing apparatus and method capable of improving encoding efficiency in motion vector encoding or decoding when an input is an interlaced signal.

  In Patent Document 1, for example, a reference PU referred to by motion vector information related to the PU and the PU belongs to the top field. On the other hand, the Co-located PU belongs to the top field, and the reference PU referred to by the motion vector information related to the Co-located PU belongs to the bottom field, so that a phase shift occurs between the fields. Therefore, the parity adjustment unit adjusts the vertical component of the motion vector information related to the Co-located PU by −½ shift.

JP 2013-121020 A

  The present disclosure provides a moving image encoding apparatus and the like that can efficiently encode a moving image having an interlace structure.

  A moving image encoding device according to the present disclosure is a moving image encoding device that encodes a moving image having an interlace structure, and a storage unit in which a plurality of fields are stored as a plurality of reference pictures, and a plurality of fields, A first reference picture list that includes only one field that is in-phase with the encoding target field and a second reference picture list that includes only one field out of phase with respect to the encoding target field among a plurality of fields are used. And an encoding unit that encodes the encoding target field as a B picture.

  A moving image encoding device or the like in the present disclosure can efficiently encode a moving image having an interlace structure.

FIG. 3 is a block diagram showing a configuration of a moving image encoding apparatus according to Embodiment 1. FIG. 2 is a block diagram illustrating a configuration of a moving picture decoding apparatus according to Embodiment 1. Conceptual diagram showing fields in the first embodiment Conceptual diagram showing the display order of fields in the first embodiment Conceptual diagram showing reference of a plurality of fields in the first embodiment Conceptual diagram showing the reference relationship between fields in the first reference example Conceptual diagram showing the reference relationship between fields in the second reference example Conceptual diagram showing an example of a reference relationship between fields in the first embodiment Conceptual diagram showing the reference relationship between fields in the third reference example Conceptual diagram showing the reference relationship between fields in the fourth reference example Conceptual diagram showing an example of a reference relationship between fields in the first embodiment Conceptual diagram showing the reference relationship between fields in the fifth reference example Conceptual diagram showing the reference relationship between fields in the sixth reference example Conceptual diagram showing an example of a reference relationship between fields in the first embodiment Flowchart showing the operation of the moving picture coding apparatus in the first embodiment. Schematic diagram showing a first application example of the moving picture coding apparatus in the first embodiment Schematic diagram showing a second application example of the moving picture coding apparatus in the first embodiment Schematic diagram showing a third application example of the video encoding apparatus in the first embodiment.

  Hereinafter, embodiments will be described in detail with reference to the drawings as appropriate. However, more detailed description than necessary may be omitted. For example, detailed descriptions of already well-known matters and repeated descriptions for substantially the same configuration may be omitted. This is to avoid the following description from becoming unnecessarily redundant and to facilitate understanding by those skilled in the art.

  In addition, the inventors provide the accompanying drawings and the following description in order for those skilled in the art to fully understand the present disclosure, and these are intended to limit the subject matter described in the claims. is not.

  In the following description, the ordinal numbers such as first, second, and third may be appropriately replaced, omitted, or newly added.

  In the following description, each of an I picture, a P picture, a B picture, and an IDR (Instantaneous Decoding Refresh) picture basically indicates a picture attribute or type. However, each of an I picture, a P picture, a B picture, and an IDR picture may indicate a picture corresponding to its attribute and type.

  In the following description, each of the top field and the bottom field basically indicates the attribute or type of the field. However, each of the top field and the bottom field may indicate the field itself corresponding to the attribute and type.

(Embodiment 1)
Hereinafter, Embodiment 1 will be described with reference to FIGS.

[1-1. Constitution]
FIG. 1 is a block diagram showing a configuration of a moving picture coding apparatus according to Embodiment 1. The moving picture encoding apparatus 100 shown in FIG. 1 includes an encoding unit 110 and a storage unit 120. The encoding unit 110 includes a subtraction unit 111, a conversion unit 112, a variable length encoding unit 113, an inverse conversion unit 114, an addition unit 115, and a prediction unit 116.

  The moving image encoding apparatus 100 encodes a moving image. Specifically, in the video encoding device 100, the encoding unit 110 includes a plurality of pictures included in a video according to a video encoding standard called AVC (Advanced Video Coding) or HEVC (High Efficiency Video Coding). Is encoded. The encoding unit 110 encodes the encoding target picture for each block.

  When the encoding unit 110 encodes the encoding target picture for each block, the prediction unit 116 generates a predicted image block for the original image block in the encoding target picture by intra prediction or inter prediction. The subtraction unit 111 generates a difference image block by subtracting the predicted image block from the original image block in the encoding target picture. The conversion unit 112 generates a coefficient block by converting the difference image block into a frequency component and quantizing it.

  The variable length coding unit 113 generates a coded block by performing variable length coding on the coefficient block. The inverse conversion unit 114 generates a difference image block by dequantizing the coefficient block and converting the coefficient block into a pixel component. The adding unit 115 generates a reconstructed image block by adding the predicted image block to the difference image block. Filter processing for reducing block distortion may be applied to the reconstructed image block.

  The encoding unit 110 generates a reconstructed picture including a plurality of reconstructed image blocks generated for the encoding target picture, and stores the reconstructed picture in the storage unit 120 as a reference picture used for inter-frame prediction. . For example, when the next encoding target picture is encoded, the prediction unit 116 refers to the reference picture stored in the storage unit 120 and performs inter-frame prediction to thereby determine the next encoding target picture. A predicted image block for the original image block is generated.

  Each of the plurality of pictures included in the moving image is classified into one of an I picture, a P picture, and a B picture. The I picture, P picture, and B picture are also called picture types.

  In the I picture, it is prohibited to perform inter prediction for each block. In a P picture, inter-block prediction is allowed for each block, and one reference picture can be referenced for one block. In B pictures, inter-block prediction is allowed for each block, and a maximum of two reference pictures can be referenced for one block.

  Specifically, when the encoding target picture is an I picture, the encoding unit 110 performs intra prediction for each block of the encoding target picture and encodes the encoding target picture. When the encoding target picture is a P picture, the encoding unit 110 encodes the encoding target picture using one reference picture list. When the encoding target picture is a B picture, the encoding unit 110 encodes the encoding target picture using two reference picture lists.

  Each reference picture list includes one or more reference pictures. The reference picture list may be referred to as a reference list. For example, when the encoding target picture is a P picture, the encoding unit 110 may select, for each block, a reference picture that is referred to in inter prediction from a plurality of reference pictures included in one reference picture list. Good.

  Also, when the encoding target picture is a B picture, the encoding unit 110 may select, for each block, a reference picture that is referred to in inter-frame prediction from a plurality of reference pictures included in two reference picture lists. Good. In this case, the encoding unit 110 may select two reference pictures for one block by selecting one reference picture from each of two reference picture lists. For example, the encoding unit 110 may perform bi-directional prediction with reference to two reference pictures for one block.

  The two reference picture lists are called L0 and L1. For example, when the encoding target picture is a P picture, only one reference picture list L0 is used out of the two reference picture lists L0 and L1. When the encoding target picture is a B picture, two reference picture lists L0 and L1 are used.

  The storage unit 120 stores a plurality of reference pictures. The reference picture stored in the storage unit 120 is a picture used for inter prediction and is a reconstructed picture for an encoded picture. When the encoding unit 110 encodes the original image block in the encoding target picture using inter-frame prediction, the prediction unit 116 refers to the reference picture to predict the original image block, thereby predicting the predicted image block. Is generated.

  The moving image encoding apparatus 100 particularly encodes a moving image having an interlace structure. A moving image having an interlace structure includes a plurality of fields each classified into a top field and a bottom field. The encoding unit 110 encodes each of the plurality of fields as a picture. Then, each of the plurality of fields is stored in the storage unit 120 as a reference picture. That is, the picture in the above description may be a field.

  FIG. 2 is a block diagram showing a configuration of a moving picture decoding apparatus corresponding to the moving picture encoding apparatus 100 shown in FIG. The moving picture decoding apparatus 200 shown in FIG. 2 includes a decoding unit 210 and a storage unit 220. The decoding unit 210 includes a variable length decoding unit 213, an inverse conversion unit 214, an addition unit 215, and a prediction unit 216.

  The moving image decoding apparatus 200 decodes a moving image. Specifically, in the moving picture decoding apparatus 200, the decoding unit 210 decodes a plurality of pictures included in a moving picture in accordance with a moving picture coding standard called AVC or HEVC. In addition, the decoding unit 210 decodes the decoding target picture for each block.

  When the decoding unit 210 decodes the decoding target picture for each block, the variable length decoding unit 213 generates a coefficient block by performing variable length decoding on the encoded block. The inverse conversion unit 214 generates a difference image block by dequantizing the coefficient block and converting the coefficient block into a pixel component.

  The prediction unit 216 generates a predicted image block by intra prediction or inter prediction. The adding unit 215 generates a reconstructed image block by adding the predicted image block to the difference image block. Filter processing for reducing block distortion may be applied to the reconstructed image block.

  The decoding unit 210 generates a reconstructed picture including a plurality of reconstructed image blocks generated for the decoding target picture, and outputs the reconstructed picture as a decoded picture.

  Also, the decoding unit 210 stores the reconstructed picture in the storage unit 220 as a reference picture used for inter prediction. For example, when the next decoding target picture is decoded, the prediction unit 216 refers to the reference picture stored in the storage unit 220 and performs inter-frame prediction to thereby perform the decoding target in the next decoding target picture. A predicted image block for the image block is generated.

  The storage unit 220 stores a plurality of reference pictures in the same manner as the storage unit 120 of the video encoding device 100. The reference picture stored in the storage unit 220 is a picture used for inter prediction, and is a reconstructed picture equivalent to a decoded picture. When the decoding unit 210 decodes a decoding target image block in a decoding target picture using inter prediction, the prediction unit 216 generates a predicted image block by predicting the decoding target image block using a reference picture. To do.

  The moving image decoding apparatus 200 corresponds to the moving image encoding apparatus 100, and particularly decodes a moving image having an interlace structure. The decoding unit 210 decodes each of a plurality of fields included in the moving image as a picture. Each of the plurality of fields is stored in the storage unit 220 as a reference picture. The picture in the above description regarding the moving picture decoding apparatus 200 may be a field.

  FIG. 3 is a conceptual diagram showing fields. For example, one frame 300 includes a pair of fields 301 and 302.

  The field 301 and the field 302 are shifted by one pixel vertically. The field 301 corresponds to the upper field of the pair of fields 301 and 302 and is classified as a top field. The field 302 corresponds to the lower field of the pair of fields 301 and 302 and is classified as a bottom field.

  Then, each of the field 301 and the field 302 is encoded as one picture.

  FIG. 4 is a conceptual diagram showing the display order of fields. In the example of FIG. 4, fields t0, t2, and t4 belong to the top field, and fields b1, b3, and b5 belong to the bottom field. Then, fields t0, b1, t2, b3, t4, and b5 are displayed in order. That is, the top field and the bottom field are displayed alternately. Thereby, the movement is displayed smoothly.

  Note that the display order of each field included in a moving image having an interlace structure basically corresponds to the imaging order of each field, and corresponds to the input order that is the order in which each field is input to the moving image encoding apparatus 100. Regarding the field order, the past direction in time corresponds to the front and the future direction in time corresponds to the rear.

  Also, when both of the two fields belong to the top field, or when both of the two fields belong to the bottom field, the two fields have an in-phase relationship. In this case, one field is expressed as a field in phase with the other field.

  Also, if one of the two fields belongs to the top field and the other belongs to the bottom field, or if one belongs to the bottom field and the other belongs to the top field, the two fields have a reversed phase relationship. . In this case, one field is expressed as a field out of phase with respect to the other field.

  In-phase and anti-phase may be expressed as in-parity and reverse parity, respectively.

[1-2. Operation]
The operation of the moving picture coding apparatus 100 shown in FIG. 1 will be described below. In the following, the operation of the moving image encoding apparatus 100 is basically shown. The video decoding device 200 performs an operation corresponding to the operation of the video encoding device 100. In the following, encoding or decoding a picture with reference to another picture may be expressed as a picture referring to another picture.

  FIG. 5 is a conceptual diagram showing reference to a plurality of fields. For example, when there is no motion, by encoding the encoding target field with reference to the in-phase field whose position matches the encoding target field, the prediction accuracy is improved and the encoding efficiency is improved. On the other hand, when there is motion, by encoding a field to be encoded with reference to a field that is in reverse phase with respect to the field to be encoded, prediction accuracy is improved and encoding efficiency is improved.

  However, the encoding target field may include a region having no motion and a region having motion. Therefore, the encoding unit 110 of the moving image encoding apparatus 100 illustrated in FIG. 1 switches the reference destination between the in-phase field and the anti-phase field for each block of the encoding target field. Specifically, the encoding unit 110 refers to an in-phase field when encoding a block in an area where there is no motion. Then, the encoding unit 110 refers to a reversed-phase field when encoding a block in an area where there is motion.

  Thereby, the encoding unit 110 can improve the prediction accuracy in both the region having no motion and the region having motion, and can improve the encoding efficiency.

  FIG. 6 is a conceptual diagram showing a reference relationship between fields in the first reference example. In FIG. 6, fields t0, b1, t2, b3, t4, and b5 are shown in display order (input order). The fields t0, t2, and t4 belong to the top field, and the fields b1, b3, and b5 belong to the bottom field.

  The field t0 is encoded as an I picture, and the fields b1, t2, b3, t4, and b5 are encoded as P pictures. The fields t0, b1, t2, b3, t4, and b5 may constitute one GOP (Group Of Pictures).

  In the example of FIG. 6, when the field t2 is encoded as a P picture, the reference picture list L0 including the field t0 that is in phase with the field t2 is used. Then, when the field b5 is encoded as a P picture, a reference picture list L0 including a field t4 that is out of phase with the field b5 is used. Thereby, the field t2 without motion and the field b5 with motion can be efficiently encoded.

  However, it is difficult to efficiently encode a field including both a non-motion area and a motion area using the reference picture list L0 including only one of the in-phase field and the anti-phase field. is there.

  Note that L0 [0] described in FIG. 6 and the like indicates the reference index 0 of the reference picture list L0. The reference index is an index for identifying a reference picture included in the reference picture list. In the example of FIG. 6, in the encoding of the field t2, it is indicated that the field t0 is included in the reference picture list L0 and the reference index 0 is assigned. In addition, in the encoding of the field b5, the field t4 is included in the reference picture list L0 and indicates that the reference index 0 is assigned.

  FIG. 7 is a conceptual diagram showing a reference relationship between fields in the second reference example. In FIG. 7, as in FIG. 6, the fields t0, b1, t2, b3, t4, and b5 are shown in display order (input order). The fields t0, t2, and t4 belong to the top field, and the fields b1, b3, and b5 belong to the bottom field.

  Similarly to FIG. 6, the field t0 is encoded as an I picture, and the fields b1, t2, b3, t4, and b5 are encoded as P pictures. The fields t0, b1, t2, b3, t4, and b5 may constitute one GOP.

  In the example of FIG. 7, when the field t2 is encoded as a P picture, a reference picture list L0 including a field t0 that is in phase with the field t2 and a field b1 that is out of phase with respect to the field t2 is used. Then, the reference destination is switched between the field t0 and the field b1 for each block of the field t2, and the field t2 is encoded. Thereby, even if the field t2 includes both a non-motion area and a motion area, the field t2 is efficiently encoded.

  Further, in the example of FIG. 7, in the encoding of the field t2, the reference index 1 is assigned to the field t0 and the reference index is assigned to the field b1 in order to identify the field t0 and the field b1 included in the reference picture list L0. 0 is assigned. Then, the reference index 0 or 1 is encoded for each block as information indicating the reference destination.

  Also in the decoding of the field t2, the reference picture list L0 including the field t0 that is in phase with the field t2 and the field b1 that is out of phase with respect to the field t2 is used as in the case of encoding. Further, in order to identify the field t0 and the field b1 included in the reference picture list L0, the reference index 1 is assigned to the field t0, and the reference index 0 is assigned to the field b1.

  Then, the reference index 0 or 1 is decoded for each block as information indicating the reference destination. Then, for each block, the reference destination is switched between the field t0 and the field b1 based on the decoded reference index 0 or 1. As a result, the same reference destination as in the case of encoding is used in decoding.

  For example, when the field b5 is encoded as a P picture, a reference picture list L0 including a field b3 that is in phase with the field b5 and a field t4 that is out of phase with respect to the field b5 is used. Reference index 1 is assigned to field b3, and reference index 0 is assigned to field t4. Thereby, even if the field b5 includes both a non-motion area and a motion area, the field b5 is efficiently encoded.

  However, in the example of FIG. 7, since the reference index 0 or 1 is encoded for each block, the amount of codes may increase. In addition, a control circuit for assigning a plurality of fields to one reference picture list may be complicated.

  Therefore, the moving picture encoding apparatus 100 illustrated in FIG. 1 uses a first reference picture list including only one in-phase field and a second reference picture list including only one field in reverse phase, The encoding target field is encoded as a B picture.

  FIG. 8 is a conceptual diagram illustrating an example of a reference relationship between fields, which is used in the moving image coding apparatus 100 illustrated in FIG. 1. In FIG. 8, the fields t0, b1, t2, b3, t4, and b5 are shown in the display order (input order) as in FIG. 6 and FIG. The fields t0, t2, and t4 belong to the top field, and the fields b1, b3, and b5 belong to the bottom field.

  In FIG. 8, the field t0 is encoded as an I picture, and the fields b1, t2, b3, t4, and b5 are encoded as B pictures. Similar to FIGS. 6 and 7, the fields t0, b1, t2, b3, t4, and b5 may constitute one GOP.

  For example, the encoding unit 110 of the video encoding device 100 adds a field t0 that is in-phase with the field t2 to the reference picture list L0 in the encoding of the field t2. Then, the encoding unit 110 assigns the reference index 0 to the field t0 of the reference picture list L0. Also, the encoding unit 110 adds one field b1 having a phase opposite to that of the field t2 to the reference picture list L1. Then, the encoding unit 110 assigns the reference index 0 to the field b1 of the reference picture list L1.

  Then, the encoding unit 110 of the video encoding device 100 uses the reference picture list L0 including only the in-phase field t0 and the reference picture list L1 including only the out-of-phase field b1 as the B picture as the field t2. Is encoded as

  For example, the encoding unit 110 of the video encoding device 100 refers to the field t0 included in the reference picture list L0 and encodes a block having no motion in the field t2. Also, the encoding unit 110 refers to the field b1 included in the reference picture list L1 and encodes a block having motion in the field t2.

  As a result, when encoding the field t2, the moving image encoding apparatus 100 refers to the in-phase field t0 with respect to the non-motion area in the field t2, and reverses the non-motion area in the field t2. Reference can be made to the phase field b1. That is, the moving picture encoding apparatus 100 can efficiently encode the field t2 by switching the reference destination between the field t0 and the field b1 for each block in the field t2.

  Further, for example, when encoding the field t2, the encoding unit 110 of the moving image encoding device 100 uses the information indicating the field t0 included in the reference picture list L0 and the field b1 included in the reference picture list L1. The indicated information is encoded. Also, the encoding unit 110 encodes information indicating the reference picture list used for encoding the block for each block in the field t2 in the reference picture lists L0 and L1.

  Then, when decoding the field t2, the decoding unit 210 of the video decoding device 200 decodes information indicating the field t0 included in the reference picture list L0 and information indicating the field b1 included in the reference picture list L1. . Then, the decoding unit 210 adds a field t0 to the reference picture list L0 and assigns a reference index 0 to the field t0. Also, the decoding unit 210 adds the field b1 to the reference picture list L1, and assigns the reference index 0 to the field b1.

  Then, the decoding unit 210 of the video decoding device 200 decodes the field t2 as a B picture using the reference picture list L0 including only the in-phase field t0 and the reference picture list L1 including only the anti-phase field b1. To do. Also, the decoding unit 210 decodes information indicating the reference picture list used for coding the block in the field t2 in the reference picture lists L0 and L1.

  Thereby, the moving picture decoding apparatus 200 can select the reference picture list used in the encoding of the block for each block in the field t2 from the reference picture lists L0 and L1. Then, the moving picture decoding apparatus 200 selects, for each block, the field used in the encoding of the block among the field t0 included in the reference picture list L0 and the field b1 included in the reference picture list L1. be able to.

  That is, the moving picture coding apparatus 100 can switch and refer to the field t0 and the field b1 without coding the reference index in coding of the field t2. In addition, in the decoding of the field t2, the moving picture decoding apparatus 200 can select the same field as the field referenced by the moving picture encoding apparatus 100 for each block without decoding the reference index.

  Also, for example, the encoding unit 110 of the video encoding device 100 determines how each block performs prediction when two reference picture lists L0 and L1 are used as shown in FIG. The block type information shown is encoded for each block. The block type indicates information such as whether to perform intra prediction, inter prediction using the reference picture list L0, or inter prediction using the reference picture list L1. On the other hand, even when only one reference picture list L0 is used as shown in FIG. 6, almost the same block type information is encoded for each block. Therefore, regardless of which method is used, the code amount corresponding to the information indicating the reference picture list used for encoding each block does not change significantly.

  Therefore, the moving picture coding apparatus 100 can switch and refer to the in-phase field t0 and the anti-phase field b1 for each block while suppressing an increase in the code amount in the coding of the field t2. .

  Also, only one field is assigned to each of the reference picture lists L0 and L1. Therefore, it is possible to simplify the control circuit for assigning fields. In particular, even in a circuit in which only one picture is allowed to be added to the reference picture list L0 or L1, the reference destination can be switched for each block between the in-phase field and the anti-phase field. .

  In the example of FIG. 8, when the field b5 is encoded, the reference picture list L0 including only the field b3 that is in phase with the field b5, and the reference picture list L1 including only the field t4 that is out of phase with respect to the field b5 Is used. Then, the reference index 0 is assigned to both the field b3 included in the reference picture list L0 and the field t4 included in the reference picture list L1.

  The moving picture encoding apparatus 100 can encode the field b5 by switching the reference destination between the field b3 and the field t4. Further, the moving picture encoding apparatus 100 can encode the field b3 and the field t4 in the same manner as the field t2 and the field b5.

  In FIG. 8, there is no field that can be referred to in front of the field b1 and in the same order as the field b1. Therefore, the moving picture encoding apparatus 100 may encode the field b1 as a B picture using the reference picture lists L0 and L1 each including only the reverse-phase field t0. Alternatively, the moving picture encoding apparatus 100 may encode the field b1 as a P picture using the reference picture list L0 including only the field t0.

  That is, when the in-phase field and the out-of-phase field can be referred to, the reference picture list L0 including only the in-phase field and the reference picture list L1 including only the out-of-phase field are used for encoding. The field may be encoded.

  In the above description, since each of reference picture lists L0 and L1 includes only one field, reference index 0 assigned to one field is not encoded. However, not only when the reference index 0 is not encoded but also when the reference index 0 is encoded, the same effect is obtained when the code amount of the reference index 0 is smaller than the code amount of the reference index 1. Is obtained.

  FIG. 9 is a conceptual diagram showing a reference relationship between fields in the third reference example. In FIG. 9, fields t0, b1, t2, b3, t4, b5, t6, b7, t8, b9, t10, and b11 are shown in display order (input order). In this example, the encoding order is the same as the display order. The upper fields t0, t2, t4, t6, t8, and t10 belong to the top field, and the lower fields b1, b3, b5, b7, b9, and b11 belong to the bottom field. A dotted arrow indicates a reference from the reference source to the reference destination.

  In FIG. 9, each field is encoded as an IDR picture or a P picture. An IDR picture is a type of I picture. Reference from a picture behind the IDR picture in the coding order to a picture ahead of the IDR picture in the coding order is prohibited.

  In FIG. 9, when the encoding target field is encoded as a P picture, the forward in-phase field is referred to if it can be referred to. Here, the front in-phase field is a field in front of the encoding target field in the display order and in-phase with the encoding target field. If a plurality of forward in-phase fields can be referred to, the forward in-phase field closest to the encoding target field in the display order is referred to from among the plurality of forward in-phase fields that can be referred to.

  Thereby, the area | region without a motion in a moving image is encoded efficiently. However, there is a possibility that a region having motion in a moving image is not efficiently encoded.

  FIG. 10 is a conceptual diagram showing a reference relationship between fields in the fourth reference example. 10, as in FIG. 9, fields t0, b1, t2, b3, t4, b5, t6, b7, t8, b9, t10, and b11 are shown in display order (input order). In this example, the encoding order is the same as the display order. The upper fields t0, t2, t4, t6, t8, and t10 belong to the top field, and the lower fields b1, b3, b5, b7, b9, and b11 belong to the bottom field. A dotted arrow indicates a reference from the reference source to the reference destination.

  Similarly to FIG. 9, each field is encoded as an IDR picture or a P picture.

  In FIG. 10, when the encoding target field is encoded as a P picture, the forward reverse phase field is referred to if it can be referred to. Here, the forward reverse phase field is a field that is forward in the display order from the encoding target field and is out of phase with respect to the encoding target field. If a plurality of forward reverse phase fields can be referred to, the forward reverse phase field closest to the encoding target field in the display order is referred to from among the referenceable forward reverse phase fields.

  Thereby, the area | region with a motion in a moving image is encoded efficiently. However, there is a possibility that an area without motion in a moving image is not efficiently encoded.

  FIG. 11 is a conceptual diagram illustrating an example of a reference relationship between fields, which is used in the moving image coding apparatus 100 illustrated in FIG. 1.

  FIG. 11 shows the fields t0, b1, t2, b3, t4, b5, t6, b7, t8, b9, t10, b11 in the display order (input order) as in FIG. 9 and FIG. Yes. In this example, the encoding order is the same as the display order. The upper fields t0, t2, t4, t6, t8, and t10 belong to the top field, and the lower fields b1, b3, b5, b7, b9, and b11 belong to the bottom field. A dotted arrow indicates a reference from the reference source to the reference destination.

  In this example, each field is encoded as an IDR picture or a B picture. When the encoding target field is encoded as a B picture, the front in-phase field closest to the encoding target field is added to the reference picture list L0 among one or more forward in-phase fields that can be referred to. In addition, among the one or more forward reverse phase fields that can be referred to, the forward reverse phase field closest to the encoding target field is added to the reference picture list L1.

  Then, the encoding unit 110 of the moving image encoding device 100 uses the reference picture list L0 including only one forward in-phase field and the reference picture list L1 including only one forward in-phase field, to encode the encoding target field. Is encoded as a B picture. For example, for each block, the encoding unit 110 refers to the forward in-phase field with respect to the area where there is no motion in the encoding target field, and sets the forward anti-phase field with respect to the area where there is motion in the encoding target field. Refer to and encode the encoding target field.

  Thereby, the moving image encoding device 100 can efficiently encode both the non-moving region and the moving region in the moving image.

  Note that when the field b1 is encoded, there is no reference forward in-phase field. Therefore, the moving picture encoding apparatus 100 may encode the field b1 as a B picture using the reference picture lists L0 and L1 each including only the reverse-phase field t0. Alternatively, the moving picture encoding apparatus 100 may encode the field b1 as a P picture using the reference picture list L0 including only the field t0. The field b7 is encoded in the same manner as the field b1.

  FIG. 12 is a conceptual diagram showing a reference relationship between fields in the fifth reference example. In FIG. 12, fields t0, b1, t2, b3, t4, b5, t6, b7, t8, b9, t10, b11, t12, and b13 are shown in display order (input order). The encoding order is, for example, the order of t0, b1, t6, b7, t12, b13, t2, b3, t4, b5, t8, b9, t10, b11.

  The upper fields t0, t2, t4, t6, t8, t10, and t12 belong to the top field, and the lower fields b1, b3, b5, b7, b9, b11, and b13 belong to the bottom field. A dotted arrow indicates a reference from the reference source to the reference destination.

  The field t0 is encoded as an IDR picture, and the field t12 is encoded as an I picture. Fields b1, t6, b7, and b13 are encoded as P pictures. Fields t2, b3, t4, b5, t8, b9, t10, b11 are encoded as B pictures.

  Further, when the encoding target field is encoded as a P picture, the forward in-phase field is referred to if it can be referred to. If a plurality of forward in-phase fields can be referred to, the forward in-phase field closest to the encoding target field in the display order is referred to from among the plurality of forward in-phase fields that can be referred to.

  Thereby, the area | region without a motion in a moving image is encoded efficiently. However, there is a possibility that a region having motion in a moving image is not efficiently encoded.

  FIG. 13 is a conceptual diagram showing a reference relationship between fields in the sixth reference example. In FIG. 13, as in FIG. 12, the fields t0, b1, t2, b3, t4, b5, t6, b7, t8, b9, t10, b11, t12, b13 are shown in the display order (input order). ing. The encoding order is, for example, the order of t0, b1, t6, b7, t12, b13, t2, b3, t4, b5, t8, b9, t10, b11.

  Similarly to FIG. 12, the upper fields t0, t2, t4, t6, t8, t10, and t12 belong to the top field, and the lower fields b1, b3, b5, b7, b9, b11, and b13 are the bottom fields. Belonging to. A dotted arrow indicates a reference from the reference source to the reference destination.

  Similarly to FIG. 12, the field t0 is encoded as an IDR picture, and the field t12 is encoded as an I picture. Fields b1, t6, b7, and b13 are encoded as P pictures. Fields t2, b3, t4, b5, t8, b9, t10, b11 are encoded as B pictures.

  In FIG. 13, when the encoding target field is encoded as a P picture, the forward reverse phase field is referred to if it can be referred to. If a plurality of forward reverse phase fields can be referred to, the forward reverse phase field closest to the encoding target field in the display order is referred to from among the referenceable forward reverse phase fields.

  Thereby, the area | region with a motion in a moving image is encoded efficiently. However, there is a possibility that an area without motion in a moving image is not efficiently encoded.

  FIG. 14 is a conceptual diagram illustrating an example of a reference relationship between fields, which is used in the moving image coding apparatus 100 illustrated in FIG. 1. In FIG. 14, the fields t0, b1, t2, b3, t4, b5, t6, b7, t8, b9, t10, b11, t12, b13 are displayed in the display order (input order) as in FIG. 12 and FIG. It is shown in The encoding order is, for example, the order of t0, b1, t6, b7, t12, b13, t2, b3, t4, b5, t8, b9, t10, b11.

  Similarly to FIGS. 12 and 13, the upper fields t0, t2, t4, t6, t8, t10, and t12 belong to the top field, and the lower fields b1, b3, b5, b7, b9, b11, b13. Belongs to the bottom field. A dotted arrow indicates a reference from the reference source to the reference destination.

  Similarly to FIGS. 12 and 13, the field t0 is encoded as an IDR picture, the field t12 is encoded as an I picture, and the fields t2, b3, t4, b5, t8, b9, t10, b11. Is encoded as a B picture. In the example of FIG. 14, the fields b1, t6, b7, and b13 are also encoded as B pictures.

  In particular, when the fields t6, b7, and b13 are encoded as the encoding target field, the front in-phase field closest to the encoding target field is added to the reference picture list L0 among the one or more forward in-phase fields that can be referred to. The In addition, among the one or more forward reverse phase fields that can be referred to, the forward reverse phase field closest to the encoding target field is added to the reference picture list L1.

  Then, the encoding unit 110 of the moving image encoding device 100 uses the reference picture list L0 including only one forward in-phase field and the reference picture list L1 including only one forward in-phase field, to encode the encoding target field. Is encoded as a B picture. For example, for each block, the encoding unit 110 refers to the forward in-phase field with respect to the area where there is no motion in the encoding target field, and sets the forward anti-phase field with respect to the area where there is motion in the encoding target field. Refer to and encode the encoding target field.

  Thereby, the moving image encoding device 100 can efficiently encode both the non-moving region and the moving region in the moving image.

  Note that when the field b1 is encoded, there is no reference forward in-phase field. Therefore, the moving picture encoding apparatus 100 may encode the field b1 as a B picture using the reference picture lists L0 and L1 each including only the reverse-phase field t0. Alternatively, the moving picture encoding apparatus 100 may encode the field b1 as a P picture using the reference picture list L0 including only the field t0.

  FIG. 15 is a flowchart showing the operation of the moving picture encoding apparatus 100 shown in FIG. For example, when the encoding target field included in the interlaced moving image is encoded by forward reference, the encoding apparatus 100 encodes the encoding target field as a B picture instead of a P picture. Hereinafter, a specific operation of the moving image encoding apparatus 100 will be described.

  First, the encoding unit 110 determines whether the structure of the moving image is an interlace structure or a progressive structure (S101). For example, the encoding unit 110 may determine whether the structure of the moving image is an interlace structure or a progressive structure in accordance with an instruction from the outside. Alternatively, it includes information indicating whether the moving image is an interlaced structure or a progressive structure, and the encoding unit 110 may determine whether the structure of the moving image is an interlaced structure or a progressive structure based on the information included in the moving image. Good.

  If the moving image structure is an interlaced structure (Yes in S101), the encoding unit 110 determines whether or not to encode the encoding target field by forward reference (S102). The encoding unit 110 may determine whether or not to encode the encoding target field by forward reference based on GOP, display order (input order), or a combination thereof. For example, the encoding unit 110 may periodically determine to encode the encoding target field by forward reference.

  Note that the above forward reference means encoding using inter prediction and referring to the forward field in the display order without referring to the backward field in the display order.

  Then, when the encoding target field is encoded by forward reference (Yes in S102), the encoding unit 110 encodes the encoding target field as a B picture (S103). Specifically, in this case, the encoding unit 110 uses the reference picture list L0 including only one forward in-phase field and the reference picture list L1 including only one forward in-phase field, and encodes the field to be encoded. Is encoded as a B picture.

  On the other hand, when the encoding target field is not encoded by forward reference (No in S102), the encoding unit 110 encodes the encoding target field using another method (S104). For example, the encoding unit 110 may encode the encoding target field as an I picture. Alternatively, the encoding unit 110 may encode the encoding target field as a P picture or a B picture by a method including backward reference.

  Also, when the structure of the moving image is a progressive structure (No in S101), the encoding unit 110 determines whether or not to encode the encoding target frame by forward reference (S105). The encoding unit 110 may determine whether to encode the encoding target frame by forward reference based on GOP, display order (input order), or a combination thereof. For example, the encoding unit 110 may periodically determine to encode the encoding target frame by forward reference.

  Note that the above forward reference means encoding using inter prediction and referring to the forward frame in the display order without referring to the backward frame in the display order.

  Then, when the encoding target frame is encoded by forward reference (Yes in S105), the encoding unit 110 encodes the encoding target frame as a P picture (S106). Specifically, in this case, the encoding unit 110 encodes the encoding target frame as a P picture using the reference picture list L0 including only one frame ahead of the encoding target frame in the display order. .

  On the other hand, when the encoding unit 110 does not encode the encoding target frame by forward reference (No in S105), the encoding unit 110 encodes the encoding target frame by another method (S107). For example, the encoding unit 110 may encode the encoding target frame as an I picture. Alternatively, the encoding unit 110 may encode the encoding target frame as a P picture or a B picture by a method including backward reference.

  With the above operation, the moving image encoding apparatus 100 encodes the encoding target field as a B picture when encoding the encoding target field included in the interlaced moving image by forward reference. In this case, the moving picture coding apparatus 100 uses the reference picture list L0 including only one forward in-phase field and the reference picture list L1 including only one forward reverse-phase field.

  As a result, the moving image encoding apparatus 100 can encode the encoding target field by switching the reference destination for each block between the in-phase field and the anti-phase field while suppressing an increase in the code amount. it can. That is, the moving image encoding apparatus 100 can efficiently encode a moving image having an interlace structure.

  In addition, when the encoding target frame included in the progressive structure moving image is encoded by forward reference, the moving image encoding apparatus 100 encodes the encoding target frame as a P picture. In this case, the moving image encoding apparatus 100 uses the reference picture list L0 including only one frame ahead in the display order from the encoding target frame.

  Thereby, the moving image encoding device 100 can encode the encoding target frame with reference to the preceding frame while suppressing an increase in the code amount. That is, the moving image encoding apparatus 100 can efficiently encode a moving image having a progressive structure.

  In the above description, a field in phase with the encoding target field is included in the reference picture list L0, and a field out of phase with respect to the encoding target field is included in the reference picture list L1. However, a field in phase with the encoding target field may be included in the reference picture list L1, and a field out of phase with respect to the encoding target field may be included in the reference picture list L0, that is, L0 and L1 may be opposite. .

  Further, in the above description, whether or not reference is possible may correspond to whether or not reference is permitted, or may correspond to whether or not the reference is stored.

  In addition, when encoding one block in the encoding target field, the moving image encoding apparatus 100 refers to both the in-phase field with respect to the encoding target field and the reverse phase field with respect to the encoding target field. May be. That is, bi-prediction may be used. For example, the moving image encoding apparatus 100 refers to both a field in phase with respect to the encoding target field and a field in reverse phase with respect to the encoding target field, and converts the motion area into the non-motion area. You may code the block which straddles.

  If one of the two fields included in each of the two reference picture lists L0 and L1 is in phase and the other is out of phase, one or both of these two fields are displayed more than the encoding target field. It may be backward in order.

[1-3. Effect]
As described above, in the present embodiment, the moving image encoding apparatus 100 encodes a moving image having an interlace structure. In addition, the moving image encoding device 100 includes an encoding unit 110 and a storage unit 120. The storage unit 120 stores a plurality of fields as a plurality of reference pictures.

  The encoding unit 110 encodes the encoding target field as a B picture using the first reference picture list and the second reference picture list. The first reference picture list includes only one field in phase with the encoding target field among the plurality of fields stored in the storage unit 120. The second reference picture list includes only one field out of phase with respect to the encoding target field among the plurality of fields stored in the storage unit 120.

  Thereby, when encoding the encoding target field included in the interlaced structure moving image, the moving image encoding device 100 suppresses an increase in the amount of code and sets the in-phase field and the reverse-phase field for each block. You can switch to and refer to. That is, the moving image encoding apparatus 100 can efficiently encode a moving image having an interlace structure.

  For example, one field included in the first reference picture list and one field included in the second reference picture list are two fields ahead of the encoding target field in display order.

  As a result, the moving picture coding apparatus 100 can refer to the two fields ahead of the coding target field by switching each block while suppressing an increase in the code amount in coding of the coding target field. it can. Therefore, the moving image encoding apparatus 100 can refer to the two fields efficiently.

  In addition, for example, one field included in the first reference picture list is displayed in the encoding target field in display order among one or more forward in-phase fields that can be referred to included in the plurality of fields stored in the storage unit 120. The closest field. In addition, one field included in the second reference picture list is the highest in the display order in the encoding target field among the one or more forward reverse phase fields that can be referred to included in the plurality of fields stored in the storage unit 120. Close field.

  Here, the one or more forward in-phase fields are one or more fields that are forward in display order from the encoding target field and in phase with the encoding target field among the plurality of fields stored in the storage unit 120. is there. In addition, the one or more forward anti-phase fields are one or more fields that are ahead of the encoding target field in the display order and out of phase with respect to the encoding target field among the plurality of fields stored in the storage unit 120. It is.

  As a result, the moving image encoding apparatus 100 can refer to the two fields in front of the encoding target field by switching each block while suppressing an increase in the code amount in encoding of the encoding target field. it can. Therefore, the moving image encoding apparatus 100 can efficiently refer to the two fields and improve the prediction accuracy.

  Further, for example, the moving image encoding apparatus 100 further encodes a moving image having a progressive structure. Then, the encoding unit 110 encodes the encoding target field as a B picture when encoding the encoding target field using only forward reference in encoding of the interlaced structure moving image. Also, the encoding unit 110 encodes the encoding target frame as a P picture when encoding the encoding target frame using only forward reference in encoding of a moving image having a progressive structure.

  As a result, the moving picture coding apparatus 100 appropriately sets the picture type of a picture to be coded by forward reference according to whether the moving picture to be coded is an interlaced moving picture or a progressive moving picture. Can be determined. Therefore, the moving image encoding apparatus 100 can efficiently encode a moving image having an interlace structure and a moving image having a progressive structure.

  Further, in the present embodiment, the video decoding device 200 includes components corresponding to the components of the video encoding device 100, and performs an operation corresponding to the operation of the video encoding device 100. For example, the moving image decoding apparatus 200 decodes a moving image having an interlace structure. In addition, the moving picture decoding apparatus 200 includes a decoding unit 210 and a storage unit 220. The storage unit 220 stores a plurality of fields as a plurality of reference pictures.

  The decoding unit 210 decodes the decoding target picture as a B picture using the first reference picture list and the second reference picture list. The first reference picture list includes only one field in phase with the decoding target field among the plurality of fields stored in the storage unit 120. The second reference picture list includes only one field out of phase with respect to the decoding target field among the plurality of fields stored in the storage unit 120.

  Thereby, in the decoding of the decoding target field, the moving picture decoding apparatus 200 blocks a field in phase with respect to the decoding target field and a field in reverse phase with respect to the decoding target field in the same manner as the moving picture encoding apparatus 100 You can switch and refer to each. That is, the video decoding device 200 can perform an operation corresponding to the operation of the video encoding device 100.

  One of the first reference picture list and the second reference picture list is the reference picture list L0, and the other is the reference picture list L1. The first reference picture list may be either the reference picture list L0 or the reference picture list L1. Further, the second reference picture list may be either the reference picture list L0 or the reference picture list L1.

  Further, when only one reference picture is included in the reference picture list, a reference index 0 is assigned to one reference picture included in the reference picture list. In this case, since the reference index 0 is not encoded for each block as a reference destination, an increase in the code amount is suppressed.

  AVC also defines a method for switching, for each block, frame coding suitable for coding a region having no motion and field coding suitable for coding a region having motion. On the other hand, HEVC does not define a method for switching between frame coding and field coding for each block. Therefore, the moving image encoding apparatus 100 that can efficiently encode an encoding target field including a region having no motion and a region having motion is particularly useful in HEVC.

(Other embodiments)
As described above, the first embodiment has been described as an example of the technique disclosed in the present application. However, the technology in the present disclosure is not limited to this, and can also be applied to an embodiment in which changes, replacements, additions, omissions, and the like are appropriately performed. Moreover, it is also possible to combine each component demonstrated in the said Embodiment 1, and it can also be set as a new embodiment. Therefore, other embodiments will be exemplified below.

  For example, in Embodiment 1, the encoding unit 110 includes a subtraction unit 111, a conversion unit 112, a variable length encoding unit 113, an inverse conversion unit 114, an addition unit 115, and a prediction unit 116. The decoding unit 210 includes a variable length decoding unit 213, an inverse conversion unit 214, an addition unit 215, and a prediction unit 216. However, these components are examples, and changes, replacements, additions, omissions, and the like may be appropriately performed on these components.

  The encoding unit 110 may be expressed as an encoder, and the decoding unit 210 may be expressed as a decoder. Each of the storage units 120 and 220 may be expressed as a storage, a buffer, a memory, a reference picture buffer, a reference picture memory, or the like.

  Further, each of the moving image encoding device 100 and the moving image decoding device 200 may selectively include a plurality of components in the present disclosure, and the moving image encoding method and the moving image decoding method are respectively A plurality of processes in the disclosure may be selectively included.

  Each component in the present disclosure may be a circuit. These circuits may constitute one circuit as a whole, or may be separate circuits. Each of these circuits may be a general-purpose circuit or a dedicated circuit.

  Further, each process in the present disclosure may be executed by a computer. For example, a computer executes each process in the present disclosure by executing a program using hardware resources such as a processor (CPU), a memory, and an input / output circuit. Specifically, the processor acquires each data to be processed from a memory or an input / output circuit, etc., calculates the data, or outputs the calculation result to the memory or the input / output circuit, etc. .

  In addition, a program for executing each process in the present disclosure may be recorded on a non-transitory recording medium such as a computer-readable CD-ROM. In this case, the computer reads the program from the non-temporary recording medium and executes the program to execute each process.

  Furthermore, the moving picture encoding apparatus 100 shown in Embodiment 1 may be applied to various apparatuses. Hereinafter, application examples of the moving image encoding apparatus 100 will be described with reference to FIGS.

  FIG. 16 is a conceptual diagram showing a first application example of the moving picture coding apparatus 100 shown in FIG. FIG. 16 shows a digital camera 401 and a cloud system 402. The digital camera 401 is an example of the moving image encoding device 100. The digital camera 401 may include the moving image encoding device 100.

  The digital camera 401 encodes a moving image having an interlace structure according to the procedure described in the first embodiment. That is, the digital camera 401 uses the reference picture list including only one in-phase field and the reference picture list including only one anti-phase field to encode the encoding target field as a B picture. Then, the digital camera 401 stores the encoded moving image in the cloud system 402 by transmitting the encoded moving image to the cloud system 402.

  Since the procedure shown in the first embodiment is applied in the encoding of the moving image having the interlace structure, the code amount is reduced. Accordingly, the amount of data transmitted in communication is reduced, and the storage capacity for data storage is also reduced.

  FIG. 17 is a conceptual diagram showing a second application example of the moving picture encoding apparatus 100 shown in FIG. FIG. 17 shows a broadcasting camera 411, a broadcasting station 412, and a television 413. The broadcast camera 411 is an example of the moving image encoding device 100. The broadcast camera 411 may include the moving image encoding device 100.

  The broadcast camera 411 encodes a moving image having an interlace structure according to the procedure described in the first embodiment. That is, the broadcast camera 411 encodes the encoding target field as a B picture using a reference picture list including only one in-phase field and a reference picture list including only one in-phase field. The encoded moving image is transmitted from the broadcast camera 411 to the broadcast station 412 and transmitted from the broadcast station 412 to the television 413.

  Since the procedure shown in the first embodiment is applied in the encoding of the moving image having the interlace structure, the code amount is reduced. Therefore, the data transmission amount in broadcasting is also reduced.

  FIG. 18 is a conceptual diagram showing a third application example of the moving picture encoding apparatus 100 shown in FIG. FIG. 18 shows a monitoring camera 421, a cloud system 422, and a video recorder 423. The monitoring camera 421 is an example of the moving image encoding device 100. The monitoring camera 421 may include the moving image encoding device 100.

  The surveillance camera 421 encodes a moving image having an interlace structure according to the procedure shown in the first embodiment. That is, the surveillance camera 421 uses the reference picture list including only one in-phase field and the reference picture list including only one anti-phase field to encode the encoding target field as a B picture.

  The monitoring camera 421 stores the encoded moving image in the cloud system 422 or the video recorder 423 by transmitting the encoded moving image to the cloud system 422 or the video recorder 423.

  Since the procedure shown in the first embodiment is applied in the encoding of the moving image, the code amount is reduced. Accordingly, the amount of data transmitted in communication is reduced, and the storage capacity for data storage is also reduced. In addition, the moving image encoded by the monitoring camera 421 basically includes a background region that does not move. Therefore, the effect obtained by applying the procedure shown in the first embodiment is great.

  As described above, the embodiments have been described as examples of the technology in the present disclosure. For this purpose, the accompanying drawings and detailed description are provided.

  Accordingly, among the components described in the accompanying drawings and the detailed description, not only the components essential for solving the problem, but also the components not essential for solving the problem in order to illustrate the above technique. May also be included. Therefore, it should not be immediately recognized that these non-essential components are essential as those non-essential components are described in the accompanying drawings and detailed description.

  Moreover, since the above-mentioned embodiment is for demonstrating the technique in this indication, a various change, replacement, addition, abbreviation, etc. can be performed in a claim or its equivalent range.

  The present disclosure is applicable to a moving image encoding device that encodes a moving image. Specifically, the present disclosure is applicable to a digital video camera, a fixed point observation camera, a surveillance camera, a security camera, or the like.

DESCRIPTION OF SYMBOLS 100 Moving image encoder 110 Encoding part 111 Subtraction part 112 Conversion part 113 Variable length encoding part 114,214 Inverse conversion part 115,215 Adder 116,216 Prediction part 120,220 Storage part 200 Moving picture decoding apparatus 210 Decoding Unit 213 variable length decoding unit 300 frame 301, 302, b1, b3, b5, b7, b9, b11, b13, t0, t2, t4, t6, t8, t10, t12 field 401 digital camera 402, 422 cloud system 411 broadcast Camera 412 broadcast station 413 TV 421 surveillance camera 423 video recorder

Claims (5)

A video encoding device that encodes a video having an interlace structure,
A storage unit in which a plurality of fields are stored as a plurality of reference pictures;
A first reference picture list including only one field in phase with the encoding target field among the plurality of fields, and only one field out of phase with respect to the encoding target field among the plurality of fields. A video encoding apparatus comprising: an encoding unit that encodes the encoding target field as a B picture using a second reference picture list including the reference picture list. The one field included in the first reference picture list and the one field included in the second reference picture list are two fields ahead in display order from the encoding target field. The moving image encoding apparatus according to 1. The one field included in the first reference picture list is a field closest to the encoding target field in display order among one or more forward in-phase fields that can be referred to included in the plurality of fields.
The one or more forward in-phase fields are one or more fields in front of the encoding target field and in phase with the encoding target field among the plurality of fields.
The one field included in the second reference picture list is a field closest to the encoding target field in display order among one or more forward-reverse-phase fields that can be referred to included in the plurality of fields.
2. The one or more forward reverse phase fields are one or more fields of the plurality of fields that are forward in display order from the encoding target field and are out of phase with respect to the encoding target field. Or the moving image encoding apparatus of 2. The video encoding device is a video encoding device that further encodes a video having a progressive structure,
The encoding unit includes:
When encoding the encoding target field using only forward reference in encoding of the interlaced structure video, the encoding target field is encoded as a B picture,
The encoding target frame is encoded as a P picture when encoding the encoding target frame using only forward reference in encoding of the progressive structure moving image. Video encoding device. A video encoding method for encoding a video having an interlace structure,
A first reference picture list including only one field in phase with respect to the encoding target field among a plurality of fields stored as a plurality of reference pictures in the storage unit; and the encoding target field among the plurality of fields In contrast, a moving picture coding method for coding the field to be coded as a B picture using a second reference picture list including only one field in reverse phase.

Images