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`block having the same size of the transform unit accord-
`ing to the scan pattern.
`[8193] The prediction mode decoder 230 reconstructs
`the intra prediction mode of the current prediction mode
`on the basis of the intra prediction information and the
`size information on the current prediction unit received
`from the entropy decoder 210. The received intra predic--
`tion information is restored through an inverse process
`of the process shown in FiG. 4.
`[8194] The reference pixel generator 240 generates;
`unavailable reference pixels of the current prediction unit,
`and adaptively fitters the reference pixels according to
`the intra prediction mode of the current prediction unit
`received from the prediction mode decoder 230. A meth-
`od of generating the reference pixels and a method of
`filtering the reference pixels are the same as those ofthe
`reference pixel generator “:42 in the intra predictor 140
`of FlG. 2.
`
`Specifically, it is determined whether reference
`[£3195]
`pixels of the current prediction unit are available. The
`reference pixels of the current prediction unit used for
`intra prediction consist of a corner reference pixel posi-
`tioned at (x = 4. y = —t), 2L upper reference pixels posi—
`tioned at (x == ’3,
`and 2L-’l , y === --’l ), and 2M left reference
`pixels positioned at (x = O, y = G,
`and 2M1). Here, L
`is a width of the current prediction unit, and M is a height
`of the current prediction unit.
`{0166] When the reference pixels for generating a pre-
`diction block are unavailable orinsufficient, reference pix-
`els are generated.
`{£3197} When all the reference pixels are unavailable,
`reference pixels are generated with a predetermined val—
`ue.
`
`ltl’l G8} When some of the reference pixels are u travail--
`able, it is determined whether the unavailable referenc 3
`pixels exist in only one direction from available pixels or
`between the available pixels.
`{£3199} When the unavailable reference pixels exist in
`only one direction from the available pixels, reference
`pixels are generated by copying the value ofan available
`pixel closest to the unavailable pixel. For example, when
`the current prediction unit
`is positioned at an upper
`boundary ofa picture ora slice, the corner reference pixel
`and the upper reference pixels are navailahle. Thus, in
`this case, the corner reference pixel and the upper ref-
`erence pixels can be generated by copying a reference
`pixel positioned at (x = 4. y = 0). Alternatively, reference
`pixels may be generated using an available reference
`pixel of the closest position and one or more available
`reference pixels. Forexample, when the corner refer ,nce
`pixel having a position (x == --1, y == --1) and reference pixels
`at positions (x = O,
`and L—f, y = 4) are available and
`reference pixels at positions (x = L, 2L—f, y = —1) are
`unavailable, reference pixels at the unavailable positions
`can be generated using change in a difference between
`a reference pixel at a position (x = L—‘l, y = —‘l) and a
`corner reference pixel value or another reference pixel
`value.
`
`20
`
`40
`
`OiOr
`
`[31 “m3 When the unavailable reference pixels exist be—
`tween the available pixels, reference pixels are generat~
`ed using two available pixels p and o adjacent to the
`unavailable reference pixels. For example, when the cor-
`ner reference pixel and the L upper reference pixels po—
`sitioned at (x = f),
`and L—t, y = —f) are unavailable,
`reference pixels existing between the reference pixel p
`at a position (x = —‘., y = 0) and the reference pixel d at a
`position (x = L, y = 4) can be generated using the refer~
`ence pixels p and Cl-
`[91113 The generated reference pixel values may be
`obtained by rounding offan average ofthe reference pixel
`p and the reference pixel d. Also. the reference pixel val—
`ues may be generated using change in difference be—
`hveen pixels values of the reference pixel p and the ref-
`erence pixel d ln this case. the reference pixel values
`may be generated by linear interpolation according to
`positions corresponding to the generated pixel values or
`using a weighted average of the two reference pixels.
`[@1123 Meanwhile, when a plurality of prediction units
`are on an upper side of the current prediction unit, there
`is a high possibility that a difference behveen boundary
`pixels present on both sides ofa boundary between two
`)f the upper prediction units will be higher than a differ-
`ence between adjacent pixels in each upper prediction
`unit. This results from an error caused by a quantization
`parameter. lt is highly probable that the error will occur
`in directional intra prediction modes in which the predic—
`tion block is generated using two adjacent reference pix-
`els.
`
`in particular, modes (mode numbers 3, 6 and
`[91133
`9) having a direction of 45° with reference to a horizontal
`or vertical direction of F'lG. 3 are most seriously affected.
`ln the vertical and horizontal
`intra prediction modes
`(mode numbers 0 and 1), one pixel is used to generate
`the prediction bloclt, and thus the vertical and horizontal
`intra prediction modes are slightly affected.
`[91143
`For this reason, a filter (smoothing filter) is ap-
`plied to the reference pixels in the directional intra pre—
`diction modes 3, 6 and 9, and is n tapplied to the refer—
`ence pixels in the vertical and horizontal intra prediction
`modes. in the DC rnode out of non-directional modes,
`the filter is not applied either. For these modes, whether
`)r not to apply the filter may be determined regardless
`of a size of the current prediction unit.
`[@1153
`in directional intra prediction modes existing be—
`tween the intra prediction mode 3. 6 or 9 and the hori—
`zontal orvertical intra prediction mode, the filter (smooth--
`ing filter) can be adaptively applied to reference pixels.
`it is preferable to increase a probability of applying the
`filter (sirioothing filter) as the direction of the directional
`intra prediction mode is relatively closer to the direction
`of the intra prediction mode having the direction of 45°.
`Specifically, when a first directional intra prediction mode
`is closer in directivity to the intra prediction mode having
`the direction of 45° than a second directional intra pre-
`diction mode. if a filter is applied to the second directional
`intra prediction mode, the filter is also applied to the first
`
`|PR2021-00827
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`directionat intra prediction mode. On the other hand, if
`the fitter is apptied to the first directionat intra predicti n
`mode, the fitter may or may not be apptied to the second
`directicnat intra prediction mode.
`[£3116] There is a high possibitity that a change in dif—
`ference between pixets in a prediction unit ofa targe size
`witt he tess than a change in difference between pixeis
`in a prediction unit of a smaii size. Thus, the number of
`directionat modes in which the fitter is appiied may be
`increase or the stronger fitter maybe a pptied as the size
`of the prediction unit increases. On the other hand, when
`a prediction unit becomes smaiier than a specific size,
`the friter may not be apptied.
`{0117]
`For one exampie, in the intra prediction mode
`3, 6 or 9 having the direction of 45°, a first fitter may be
`appiied to a prediction unit having a size eduai to orsmati—
`er than a first size, and a second fitter that is stronger
`than the first fitter may be apptied to a prediction unit
`having a size targer than the first size. The first size may
`vary according to directionat prediction modes.
`{0118]
`For another exam pie,
`in the intra prediction
`mode 5 existing between the verticat
`intra prediction
`mode and the intra prediction mode 8 having the direction
`0M5", no fitter may he a pptied to a prediction unit having
`a size equai to or smatier than a second size, the first
`fitter may be apptied to a prediction unit having a size
`iarger than the second size and eguat to or smatter than
`a third size, and the second fitter may be apptied to a
`prediction unit having a size iarger than the third size.
`The second size and the third size may vary according
`to directionai prediction modes.
`[(31 1Q] The first fitter may be a B—tap fitter if, 2, f] or a
`5~tap fitter [1, 2, 4, 2, i]. The second fitter has a greater
`smoothing effect: than the first fitter.
`{012%} The prediction biock generator 250 generates
`a prediction biock according to the intra prediction mode
`of the current prediction unit received from the prediction
`mode decoder 230. A method of generating the predic-
`tion biock is the same as that of the prediction biock gen—
`erator 142 in the intra predictor 140 of F'tG. 2.
`[0121} That is, in the directionat intra prediction mode,
`the corresponding reference pixets vary according to the
`intra prediction modes. Forexamoie, in the verticai mode,
`t. upper reference pixets positioned at (x === t),
`and i_.-,’t
`= ~i) are used, and in the horizontat mode, L teft refer-
`ence pixeis positioned at (x = -’i, y = 0,
`and L—f) are
`used.
`
`in non-directionat infra prediction modes, the
`[0122}
`corner pixei, L upper reference pixeis positioned at (x =
`(i,
`and L—f, y: d) and i. teft reference pixeis positioned
`at (x === -1 . y === 0,
`and L- t) are used. The non-directionat
`intra prediction modes are the DC mode and the pianar
`mode.
`
`20
`
`40
`
`tn the pianar mode, a reference pixei ofa pre—
`[£3123]
`diction Mode is generated using the corner reference pix-
`ei, a teft reference pixet and an upper reference pixet.
`When a reference pixei to he generated is positioned at
`(a, b), the reference pixet cf the prediction ptoch X(a, b)
`
`OiOr
`
`is generated using the corner reference pixei C(x = -t, y
`= ~ 1), an upper reference pixet 'i'tx = a, y = —’r) and a teft
`reference pixet t_(x === --f, y == h). Specificatty, Xta, b) may
`be th = —1, y 2 h)+T(x = a, y = —f)~C(x = 4, y = 4).
`[@1243
`in the intra prediction mode existing to the right
`side of the verticat mode (mode number 0) of HG. 3,
`there is a pcssibiiity that differences between pixets of a
`tower teft region of the generated prediction biock and
`pixets of the originat prediction unit wiii increase if the
`prediction hiock is generated using onty upper reference
`pixets. However, when a prediction tricok is generated
`using upper reference pixeis and ieft reference pixeis for
`severat modes among the modes, the difference can be
`reduced. This effect is greatest in the intra prediction
`mode 6. Aiso in intra prediction modes existing under the
`horizontat mode (mode number i) of HG. 3, same meth~
`od may be apptied. and the effect is greatest in the intra
`prediction mode 9.
`[@1253 Thus, in the prediction mode 6 or 9, a prediction
`pixet may be generated using corresponding (for exam
`pie, positioned at 45° of the prediction pixet) one upper
`interpotation reference pixet and one teft interpoiation ref-
`erence pixet. T'he prediction pixei may be generated by
`tinear interpoiaticn of the one upper interpotation refer-
`ence pixei and the one teft interpoiation reference pixet
`or using a rounded off average. Likewise, in a predeter—
`mined number of intra prediction mcdes adiacent to
`mode 6 or 9, a prediction otook may be generated using
`the teft reference pixeis and the upper reference pixeis.
`in this case, to reduce comptexity, the aforementioned
`method may not he apptied in intra prediction modes hav-
`ing mode numbers greater than a predetermined mode
`number (for exampie, 9 or 17‘). Atso, the method may be
`appiied to cnty a current prediction unit having a size
`eouai to or iarger than a predetermined size. The prede—
`termined size is 8X8 or iSXfS.
`
`[91263 The prediction hiock post-processor 260 adap-
`tiveiy fitters the prediction tricok generated by the predic-
`tion biock generator 250 according to the intra prediction
`mode of the current prediction unit received from the pre—
`diction mode decoder 230. The prediction btock
`post—processor may be integrated into the prediction
`biock generator 250. A prediction biock fittering method
`is the same as that of the prediction bicck post-processor
`144 of the intra predictor 140 of FiG. 2.
`[@1273 That is, to reduce differences in pixei vaiues be—
`tween a reference pixet and pixets in the prediction biock
`adjacent to the reference pixet, the prediction btock fitter
`260 adaptiveiy fitters some or aii pixeis in the prediction
`biock adjacent to the reference pixet according to the
`intra prediction mode. The pixets adjacent to the refer-
`ence pixet exist in the prediction bicck.
`[@1233
`in the pianar mode, pixets in the prediction biock
`adjacent to a reference pixei are generated using the
`reference pixei, and thus no fitter is appiied.
`[9129}
`in the DC mode, an average of reference pixeis
`is used to generate prediction pixei, and thus a fitter is
`apptied. Different type of fitter can he used according to
`
`|PR2021-00827
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`

`21
`
`E? 2 603 613 A2
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`22
`
`the size of the prediction unit (the size of the prediction
`biock). in a prediction unit of a iarge size. a fitter that is
`the same as used in a prediction unit of a smaii size or
`a strong fiiter having a great smoothing effect can be
`used.
`
`in intra prediction modes existing
`i‘i/ieanwhiie,
`[£3130]
`to the right side of the verticai mode (mode number 0) of
`FiG. 3,
`if the prediction biock is generated using cniy
`upper reference pixeis there exists a possibiiity thata
`difference betweenarapixei in the generated predictit3n
`biocit and the corresponding pixei of the originai predic-
`ticn unit wiii increase as the position of the pixei in the
`generated prediction biock is going down to the under~ieft
`region. in particuiai: the difference remarkabiy increases
`in the intra prediction mode 6.
`[9131} Likewise in intra prediction modes existing un—
`der the horizontai mode (mode number 1) of HS. 3} ii a
`prediction biock is generated using oniy ieit reference
`pixeis there exists a possibiiity that a difference between
`a pixe i in the generated prediction biock and the corre-
`spending pixei of the originai prediction unitwiiiincrease
`as the position of the pixei in the generated prediction
`biock is going to the upper~rig
`region. T'he differ,nce
`remarkabiy increases in the intra prediction mode 9.
`[£3132]
`in the verticai mode (mode number 0), a differ—
`ence between a pixei in the prediction biock and the cor—
`responding pixei oi the originai prediction unit increases
`as the position of the pixei is going down. in the horizontai
`mode (mode number 1). a difference between a pixei in
`the prediction biock and the corresponding pixei of the
`originai prediction unit increases as the position of the
`pixei is going right.
`[£3133] Therefore, to reduce the difference. some pre—
`diction pixeis in the prediction biock can be adaptiveiy
`fittered according to the directionai intra prediction mode.
`in this case, the some prediction pixeis in the prediction
`biock are fiitered using reference pixeis in the prediction
`unit not used for gene “ating the prediction biock.
`[£3134] A region to be fiitered may be set differentiy ac—
`cording to a directionai intra prediction mode. As a direc—
`tion of intra prediction mode gets <2:ioser to mode 6 or
`mode 9, the region to be tiitered may become iarger or
`remain the same.
`
`For one examp ie when a size ofa predict
`[8135]
`unit is QNXEN in the intra prediction mode 6, a fiiter may
`be appiied to oniy a predetermined number (1~") of intra
`prediction modes adjacent to the intra prediction mode
`5 among intra prediction modes existing to the right side
`of the verticai mode (mode number 0).
`in this case, to
`reduce compiexity, no fiiter may be appiied to the intra
`prediction mode having a mode number greater thana
`predetermined mode numberifiiorexampie. 9 or i 7). Aiso,
`some pixeis in the prediction biock may be adaptiveiy
`fittered according to a size of the prediction unit. As the
`size ofthe prediction unit increasesa the number of pixeis
`to be tiitered may increase or remain the same.
`[9136}
`For another exampie in the intra prediction
`mode 5, the prediction biock may not be fiitered if the
`
`20
`
`4o
`
`OiOi
`
`size of the prediction unit is 4X4. if the size of the pre—
`diction unit is 8X8 or 1 6X 1 t5, oniy fouriower ieft boundary
`pixeis of the prediction biock among eight pixeis posi-
`tioned at (x = O, y = t),
`and 7) may he fiitered. if the
`size of the prediction unit is 32x32 cr iarger, aii eight of
`the boundary pixeis may be fittered.
`[G137]
`Strength of tiiter to be appiied to the pixeis in
`the prediction biock may aiso vary according to the size
`of the prediction unit. As the size of the prediction unit
`increases. the tiiter strength ma y increase or remai.3. the
`same.
`
`[@1333 The image reconstructor 270 receives a predic—
`tion biock from the prediction biock generator 250 or the
`prediction biock fiiter 250 in units of prediction units ac—
`cording to the intra prediction mode. The image recon-
`structor 270 receives a residuai biock reconstructed by
`the residuai signai decoder 220 in units of transform units.
`The image reconstructor 270 generates a reconstructed
`image by adding the received prediction biock and resid—
`uai biock. The image may be recoirstructed in units:
`coding units.
`[9139} White the invention has been shown and de-
`scribed with reference to certain exempiary embodi~
`ments thereof. it wiii be understood by those shifted in
`the art that various changes in form and detaiis may be
`made therein without departing from the spiritand scope
`of the invention as (ieiined by thea' ppendediciaims.
`
`Ciaims
`
`1. An intra prediction decoding apparatus. comprising:
`
`an entropy decoder configured to restore (roan--
`tized residuai coefficients, intra prediction infor—
`mation and size information on a prediction unit
`from a received bit stream;
`a prediction mode decoder configured to restore
`an intra prediction mode ofthe current prediction
`unit on the basis of the intra prediction informa—
`ti<2on and the size information on the current ore--
`diction unit received from the entropy decoder;
`aresiduai signai decoder configured to restore
`aresidiuai signaia ccord ing <2ti theintra prediction
`mode received from the prediction mode decod-
`er;
`
`a referie.ce pixei generator configured to gen—
`erate unavaiiabie reference pixeis of the current
`prediction unit, and to adaptiveiy fitter the refer-
`ence pixeis on the basis of the intra prediction
`mode of the current: prediction unit received from
`the prediction mode decoder;
`a prediction biock generator configured to gen—
`erate a prediction biock using reference pixeis
`corresponding to the intra prediction mode re—
`ceived from the prediction mode decoder;
`a prediction biock fitter configured to adaptiveiy
`fitterthe pr<2idiction biock generated from the pre-
`
`|PR2021-00827
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`Unified EX1002 Page 927
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`

`23
`
`E? 2 603 613 A2
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`24
`
`diction hiock generate“ according to the intra
`prediction mode received from the predictin
`rnode decoder; and
`an image reconstructor configured to receive the
`prediction hiook from the prediction biock gen—
`erator or a prediction oiock fiiter in units of pre—
`diction units according to the intra prediction
`mode received from the prediction mode decod-
`eri and generate a reconstructed image using a
`restored residuai piock received from the resid-
`
`uai signai decoder.
`
`The intra prediction decoding apparatus of ciaim 1,
`wherein the reference pixei generator adaptiveiy fii-
`ters the reference pixeis according to a size of a pre-
`diction unit in intra prediction modes having direction
`between intra prediction mode 31 {3 or 9 having a
`direction of 45° and the horizontai mode or the ver-
`ticai mode.
`
`The intra prediction decoding apparatus of ciaim 1,
`wherein the reference pixei generator appiies no fii-
`ter to reference pixeis of a prediction unit smaiier
`than a predetermined size.
`
`The intra prediction decoding apparatus of ciaim t,
`whereim when; among a first: directionai mode and
`a second directionai mode present between a hori-
`zontai mode or a verticai mode and an intra predic-
`tion mode 3 5 or 9 having direction of 45° with re—
`spect to the horizontai mode or the verticai mode,
`the first directionai mode has cioser directivity to the
`intra prediction mode having the direction of45° than
`the second directionai rnode if the reference pixei
`generator appiies a fiiter to reference pixeis of the
`second directionai mode, the reference pixei gener-
`ator aiso appiies the fitter to reference pixeis of the
`first directionai mode.
`
`The intra prediction decoding apparatus of ciaim t,
`whereim when the intra prediction mode is a pianar
`mode, the prediction biocit generator generates pre-
`dioted pixeis of the prediction oiock using a corner
`reference pixeiq a ieft reference pixei and an upper
`reference pixei.
`
`The intra prediction decoding apparatus of ciaim t,
`whereim when the intra prediction mode is a verticai
`mode, the reference pixei generator does not fitter
`the refer,noe pixeis, and
`the prediction hicck fitter uses reference pixeis that
`have not been used for generating the prediction
`hiock to fitter some pixeis in the prediction biock.
`
`The intra prediction decoding apparatus of ciaim 1,
`wherein, when the intra prediction mode is an intra
`prediction mode having direction of 45° with respect
`to a verticai rncde (mode nurn her 6) or among a pre-
`
`20
`
`40
`
`OiOi
`
`determined number of intra prediction modes having
`directivity ciose to the intra prediction mode, the ore
`diction hiook generator generates;
`the prediction
`biocit using upper reference pixeis and iett reference
`pixeis.
`
`|PR2021-00827
`
`Unified EX1002 Page 928
`
`IPR2021-00827
`Unified EX1002 Page 928
`
`

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`E? 2 603 613 A2
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`|PR2021-00827
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`|PR2021-00827
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`Unified EX1002 Page 933
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`IPR2021-00827
`Unified EX1002 Page 933
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`3 des brevets
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`Patentamt
`: Eurep'a‘ischss
`European
`E‘atent Office
`Bffice eurapéen
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`(19:)
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`.‘2
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`A “A
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`~../
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`EP 2 999 914 A2
`
`EUROPEAN PATENT APPLECATEQN
`pubiished in accordance with Art. 153(4) EPC
`
`(43) Date of puhiication:
`95.96.2913 Buiietin 2913/23
`
`(51) int CL:
`”(MN 7/34 (2005.01)
`
`(21) Appiication number: 118147982
`
`(22) Date of fiiing: 29.9?.2911
`
`(86) internationat appiicaticn number;
`PCT/KRZG11I995592
`
`(87) internationai pubiicetion number:
`W0 2912/913198 (99.92.2912 Gazette 2912196)
`
`
`(84) Designated Contracting States:
`AL AT BE BG CH CY CZ DE DK EE ES FE FR GB
`GR HR HU EE ES ET LE LT LU LV MC MK MT NL N3
`PL PT RO RS SE $15K SM TR
`
`(72) inventor: 0h, Soc-mi
`eeou; 138—998 (KR)
`
`(74) Representative: Grtinecker, Kinkeidey,
`Stockmair 8t Schwanhéuseer
`
`(3(3) Priority: 28.98.2911 KR 29119962693
`31.97.2919 KR 29199974492
`
`Leopoidstraeee it
`89892 Mt’inchen (DE)
`
`(71) Appiicant: Oh, Soc-mi
`33201.3! 138-998 (KR;
`
`(54-)
`
`PREQECTEGN BLGCK GENERATENG SEVECE
`
`A prediction oicoit generating device of the
`(57)
`present invention determines additionai information for
`generating a prediction biock inciuded in an additionai
`information container received. and an intra prediction
`mode of a current prediction unit using avaiiapie intra
`prediction mode candidate information ofthe current pre—
`diction unit. generates; reference pixeis that are not in e
`unavaitabie position for generating an intra prediction
`biock by using avaiiabie reference pixeis, adaptiveiy iii-
`
`terse the reference pixeie ciose to the current prediction
`init based on the determined intra prediction mode of the
`current prediction unit or size information or" the current
`prediction unit. and generates a prediction ciock of the
`current prediction unit using the reference pixeis corre-
`sponding to the determined intra prediction mode of the
`current prediction unit. Therefore. the present invention
`can improve image compression ratio by generating the
`prediction bicck cicse to an originai image.
`
`
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`
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`|PR2021-00827
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`Unified EX1002 Page 934
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`iN
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`0w: FRED
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`P2699914A2
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`IPR2021-00827
`Unified EX1002 Page 934
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`...i.
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`£532 603 614A2
`
`2
`
`{Description
`
`[Technicai Fieid]
`
`[STEM] The present invention reiates to a prediction
`piock generating device, and more particuiarty, to an ap—
`paratus of generating a prediction hiock capahie of min--
`imize the amount of coding bits of a residuai biock.
`
`[Background Art]
`
`in image compression methods such as Motion
`[£3992]
`Picture Experts Group (MF’EG)~1, MPEG—2. MPEG—4
`and HEM/MPEG4 Advanced Video Coding (AVG‘, one
`picture is divided into macrobiocks (MBs) to encode an
`image. 'Then, the respective MBs are encoded using inter
`prediction or intra prediction.
`{£3093}
`in intra prediction, a current biOCk of a current
`picture is encoded notusing a reference picture, but using
`vaiues oi pixeis spatiaiiy adjacent to the current piock.
`An intra prediction mode with iittte distortion is seiected
`by comparing a prediction biock generated using the ad-
`jacent pixei vaiues with an originai MB. Then, using the
`seiected intra prediction mode and the adjacent pixei vat--
`ues, prediction vaiues ofthe current biock are caicuiated.
`Differences between the prediction vaiues and pixeis vai—
`ues of the originai current picck are caicuiated and then
`encoded through transform coding, quantization and en-
`tropy coding. The intra prediction mode is aiso encoded.
`[9&de
`intra prediction modes are generaiiy ciassified
`into 4K4 intra prediction mode, 8X8 intra prediction
`mode and 16%th intra prediction mode for iuminance
`components and intra prediction mode for chrominance
`components.
`{@665}
`in ’iBXtB intra prediction mode according to a
`prior art, there are four modes ofa verticai mode, a hor-
`izontai mode, a direct current (DC) mode and a piano
`mode.
`
`jacent to current oiock do not exist or are not aiready
`encoded, it is impossioie to appiy some or aii of the intra
`prediction modes to the current hiock. Aiso, when intra
`prediction is performed by seiecting prediction rnode
`among applicabie intra mode, a residue signai between
`a prediction hiock and the current piock becomes iarge.
`Therefore, the coding efficiency is degraded.
`
`[Disciosure]
`
`{Technicai Prooiem]
`
`[90:18} The present invention is directed to an appara—
`tus of generating a prediction picck simiiar to an originai
`biock.
`
`{Technicai Sciuticn]
`
`20
`
`room One aspect of the present invention provides
`an apparatus inciuding: an intra prediction mode decod-
`ing unit configured to restore an intra prediction mode of
`a current prediction unit using additionai information in-
`ciuded in a received additionai information container and
`
`avaiiabie intra prediction mode candidate information of
`the current prediction unit; a reference pixei generating
`unit configured to generate reference pixeis using avaii—
`apie reference pixeis; a reference pixei fiitering unit con--
`figured to adaptiveiy fitter the reference pixets based on
`the restored intra prediction mode of the current predic-
`tion unit and a size of the curr nt prediction unit; and a
`prediction biOCk generating unit configured to generate
`a prediction biock of the current prediction unit using the
`reference pixeis corresponding to the restored intra pre—
`diction mode.
`
`in 4X4 intra prediction according to the priorart,
`[£3996]
`there are nine modes of a verticai mode, a horizontai
`mode. a DC mode, a diagonai down--ieft mode, a diagonai
`down-right mode, a verticai right mode, a verticai ieft
`mode, a horizontai—up mode and a horizontai—down
`mode.
`
`4o
`
`{£3097} Each prediction mode has indexed according
`to the frequency of use of the respective modes. The
`\ieiticai mode ofwhioh mode number is 0 shows the high—
`est: possihiiity of being used most freouentiy for perform--
`ing intra prediction on a target piock, and the horizon-
`tai~up mode ofwhich mode numberis 8 shows the highest
`possihiiity of being used most infreduentiy.
`{£3098} According to H.254 standards, a current biock
`is encoded using a totai of 13 modes, that is, 4 modes
`of the 4X4 intra prediction and 9 modes of the toxto
`intra prediction. A bit stream of the current picck is gen-
`erated according to an optimai mode among these
`modes.
`
`(Advantageous Effects}
`
`[96123 An apparatus according to the present invention
`generates reference pixeis and adaptiveiy fitters the ref—
`erence pixeis in order to generate a prediction hiock min—
`imizing the difference between the prediction hiock and
`an originai biock. Aiso, by adaptivety fiitering the predic—
`tion piock according to intro prediction mode, residuai
`signais become smaiier and thus an image compression
`can be improved.
`
`[Description of Drawings]
`
`[3913}
`
`HQ. 1 is a hiock diagram iiiustrating a moving picture
`coding apparatus according to the present invention.
`HS. 2 is a fiow chart iiiustrating an operation of a
`scanning unit according to the present invention.
`FiG. 3 is a biock diagram iiiustrating a moving picture
`decoding apparatus according to the present inven-
`tion.
`
`OiOi
`
`[8099] However. when some or at! vaiues of pixeis ad-
`
`HQ. 4 is a bicck diagram iiiustrating an intra predict-
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`|PR2021-00827
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`Unified EX1002 Page 935
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`IPR2021-00827
`Unified EX1002 Page 935
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`3
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`E92 603 614A2
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`4
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`tion unit according to the present invention.
`PEG. 5 is a c ,nceptuai diagram showing positions of
`reference pixeis used for intra prediction according
`to the present invention.
`FEG. 6 a fiow chart iiiustrating a process ofgenerating
`reference pixeis according to the present invention.
`FEG. 7’ is a biock diagram ittustrating an intra predic-
`tion unit ofa moving picture decoding apparatus ac-
`cording to the present invention.
`
`[Mode for invention}
`
`the
`embodiments of
`[£3914] Hereinafter. various
`present invention wiii be described in detaii with refer-
`ence to the accompanying drawings. However.
`the
`present invention is not iimited to the exem piary embod—
`iments disciosed heiow. but can be impiemented in var--
`ious types. Therefore, many ether modifications and var-
`iations of the present invention are possible. and it is to
`be understood that within the scope of the disoiosed con--
`cept, the present invention may be practiced otherwise
`than as has been specificatiy described.
`[@151
`For image coding, each picture consists of a
`piuraiity of siices. and each siice consists of a piuraiity of
`coding units. Since an image of a high-definition (HD)
`grade or higherhas many smooth regions. an image com—
`pression can be improved by encoding the image with
`coding units oftargerthan an M8 ofwhich size is 16X 1 6.
`[9616} Asize ofthe coding unitaccording to the present
`invention may be 16x16, 32x32 or 84x64. A size of the
`coding unit may aiso be 8x8 or iess. A coding unit of the
`iargest size is referred to as a super macrobiocit (3MB).
`A size cfSMB is indicated by a smaiiest size ofthe coding
`unit and depth information. The depth information indi--
`cates a difference vaiue between the size of EMS and
`
`the smaiiest size of the coding unit.
`[801?] Therefore, coding units to he used for coding
`pictures may he SMB or sub-hiock of 5MB. The coding
`units are set to defauits vaiue or are indicated in a se—
`
`quence header.
`[0818} A 53MB consists of one or more coding units.
`The 8MB has a form of a recursive coding tree so as to
`inciude the coding units and a division structure of the
`coding units. When the Sit/IE} is not divided into four
`sub—coding units. the coding tree may consist of informa-
`tion indicating that the SMB is not divided and one coding
`unit. When the SMB is divided into four sub—