US008165211B2(12) Umted States Patent(10) Patent N0.2

Ngan et al.
(54)

US 8,165,211 B2(45) Date of Patent:

METHOD AND APPARATUS OF

Apr. 24, 2012
511111131 etf11~ ~~~~~~~~~~~~~~~~~~ ~~ 348/452_

ac nn1s

DE INTERLACING VIDEO(75)

2004/0205539 A1*

IIWBIIIOFSI Klllg Ngl Ngall, Hong Kong (CN); J16
Dong, Hangzhou (CN); Yan Huo,

ghenzhen (CN)
-

_

-

-

(73) Asslgnee' £1011‘?
Klong ?pphedhsilelifte:‘ndec no ogy
esearcns 1 u e

6/2006 Stoner ................ .. 375/24016
9/2006 Katayama et a1. ..... .. 375/24016

Pau et a1.

..... .. 348/448

2007/0229704 A1

10/2007 Mohapatra

2007/0230571 A1*

10/2007

Kodama ................. .. 375/240.12

2008/0069214 A1*

3/2008

Hagaiet a1.

.... .. 375/240.14

Primary Examiner i Gary Mui)

Assistant Examiner * Hicham Foud

Subject to any disclaimer, the term of thispatent is extended or adjusted under 35(74) Attorney’ Age/1Z1 0r Fir T Ella Cheong Hong Kong;
Margaret A‘ Burke’ Sam T'Ylp

U.S.C. 154(b) by 999 days.

(57)(21) Appl. No.: 12/129,891

ABSTRACTThe presently claimed invention adaptively selects a local

_

(22)

8/2005

2006/0126739 A1 *2006/0209960 A1*

cued by exammer

PKark, SgitIm, New Terr1tor1es, Hong( * ) Notice:

2005/0179814 A1*

2008/0069230 A1* 3/2008 Kondo et a1. .......... .. 375/24016* .
.

Company Limited, Hong Kong ScienceOng (10/2004 Mak et a1. ................... .. 715/511

de-interlacing method according to information from a com

Flled?

May 30a 2008_

pressed video bitstream. According to one embodiment, suc__cessive images from a video bitstream are ?rst reconstructed.

(65)

Pnor Pubhcatlon Data
US 2009/0296815 A1
Dee 3’ 2009

Syntax elements, selected from a macroblock type, a mac
roblock partition, a motion vector, a distance from a reference
frame, the existence of non-Zero transform coef?cients and(51)

Int_ C]_
H04N 7/12(200601)

the distribution of transform coe?icients, are then extracted
from this bitstream. Based on the syntax elements, a de(52)

us. Cl. ................................................ .. 375/240.16

interlacing algorithm is decided from an algon'thm Set for(58)

Field of Classi?cation Search ...................... .. Noneeach image region in a Video frame‘ Algorithms in the algo'

See application ?le for Complete Search history'rithm set include motion compensation, edge-based line aver

References Cited

aging, and line averaging. Each image region is thereby interpolated using the de-interlacing algorithm andcomplementary motion compensation. The complementary
motion compensation de-interlaces the image region using an(56)

US. PATENT DOCUMENTS

inverse of motion vectors extracted from a bitstream clip

6,269,484 B1

7/2001 Simsic

7,227,895 B1*

6/2007 Wang et a1. ............ .. 375/240.16

7,844,580 B2 *7,876,830 B2 *11/20101/2011

representing neighboring frames.

Srivastava et a1. .......... .. 707/690
Katayama et a1. ..... .. 375/240.16

11 Claims, 7 Drawing Sheets

,2. O

102
101

104

140

§

110

Reconstructed frames

94

Reordered frames

150

é

106

H.264
bitstream

H.264

—»

Deainterlaced frames

Decoding

1

1

Delayer

Syntax Element

andextractor

Re.

120

+

10 B B2 P3B4 B5—>

2-D mode maps
130
103

Stage

.. 11
1

ordering

Decision Stage

Interpolation

2- mode maps

4105

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1

2

METHOD AND APPARATUS OF
DE-INTERLACING VIDEO

from the video bitstream; deciding a de-interlacing algorithm
from an algorithm set for each image region in a video frame

based on the syntax elements; and interpolating the image

regions using the de-interlacing algorithm and complemen

TECHNICAL FIELD

tary motion compensation.
The complementary motion compensation de-interlaces

The present invention relates generally to video process
ing. More particularly, aspects of the invention relate to methods and apparatus for de-interlacing video.

the image regions using the inverse of motion vectors
extracted from the bitstream clip representing neighboring
frames. In one exemplary embodiment, it interpolates image

BACKGROUND OF THE INVENTION

pixels from an immediately neighboring frame based on the
inverse of a motion vector, Wherein said motion vector points
to the current frame from said immediately neighboring
frame.
Advantageously, the algorithm set further includes line

Many known TV and video standards, such as NTSC,
utiliZe interlacing for video coding. For example, odd or evenlines of an image are draWn on the screen alternatively forevery 60th of a second, With each line being updated at a frame
rate of 30 frames per second. One reason is that traditional,
long established display devices such as CRT televisions
could not support high refresh rate for full frame. Throughaveraging, edge-base line averaging and motion compensation.
The method may also include storing the results of decid

ing a de-interlacing algorithm for each image region in an

video interlacing, ?ickering canbe reduced due to persistenceof vision effect While the vertical resolution can be maintained.

array.
20

The decision of using a de-interlacing algorithm may bebased on syntax elements such as: macroblock types, mac

In modern display devices that do not support display ofinterlaced video, such as LCD display types, de-interlacing

roblock partitions, motion vectors, the distance from the ref
erence frame, the existence of non-Zero transform coef?

has to be applied to interlaced video to obtain the missing
cients or the distribution of transform coe?icients.
lines in each of the odd line and even line frames by interpo 25
The method may be applied to video bitstream coded underlation.
video standards such as AVS and H.264.
Other aspects of the claimed invention are also disclosed.
SUMMARY OF THE INVENTION
BRIEF DESCRIPTION OF DRAWINGSThis presently claimed invention adaptively selects a local 30
de-interlacing method according to the information from thecompressed video bitstreams, and is compatible With parallel

Embodiments of the invention are described in more detailhereinafter With reference to the draWings, in Which:
FIG. 1 is a block diagram illustrating a de-interlacing sys

implementation.
A video frame can be de-interlaced by many methods,

tem in accordance With an embodiment of the claimed inven

including line averaging, edge-base line averaging, and 35 tion.
motion compensation. Among these methods, motion com

FIG. 2 is a How chart for determining the mode of depensation is often more preferred because it can provide ainterlacing for intra-coded marcoblocks in the decision stage.

superior image quality compared to line averaging.

FIG. 3 is a How chart for determining the mode of deIn general, the macroblocks in a coded video can be clas
interlacing for inter-coded marcoblocks in the decision stage.
si?ed into intra-coded macroblocks and inter-coded macrob 40
FIG. 4 is a block diagram illustrating the interpolation
locks. While intra-coded macroblocks are coded Without
stage.

adopting motion compensation, such kind of macroblocks

FIG. 5 depicts the scenario Where complementary motion

may actually involve motion. HoWever, since they are tem
porally too far aWay from their reference ?elds, motion com

compensation is used in accordance With an embodiment of
the claimed invention.
FIG. 6 depicts the method of complementary motion com

pensation is not utiliZed as a coding method in video standards.

45

pensation for interpolating missing pixels by reference toAspects of the presently claimed invention have been

existing pixels in immediately neighboring frames in accor

developed to make full use of the information from com

dance With an embodiment of the claimed invention.
FIG. 7 is a How chart representing embodiments of theclaimed method.

pressed video bitstreams, such as an H.264 bitstream, in orderto enhance the chance of applying motion compensation, 50
hereinafter referred as complementary motion compensation.
One type of information to be considered in determining
de-interlacing methods is the siZe of the macroblockpartition,

DETAILED DESCRIPTION

Which indicates the smoothness of motion and textures.
Improved methods and apparatus for de-interlacing video
Another type of information to be considered is the distribu 55 frames are disclosed herein. In the folloWing description,
numerous speci?c details, including macroblock siZes, frametion of the transform coe?icients, Which re?ects the presenceof edges. Additionally, motion vector is also taken intosequences, image patterns, pixel patterns, and the like are set
account for ?nding the reference blocks in temporally neighforth. HoWever, from this disclosure, it Will be apparent toboring ?elds.
those skilled in the art that modi?cations, including additions
Complementary motion compensation alloWs ?nding a 60 and/or substitutions may be made Without departing from thereference block in non-referred neighboring ?elds such as
scope and spirit of the invention. In other circumstances,
speci?c details may be omitted so as not to obscure the inven
When they are not indicated by the video bitstream, When thereference ?elds indicated by the video bitstream are tempo
tion. Nonetheless, the disclosure is Written as to enable one
skilled in the art to practice the teachings of the embodiments
rally too far aWay.

In certain embodiments, the method of decoding the video 65 of the invention Without undo experimentation.
bitstream includes reconstructing successive images from a
FIG. 1 is a block diagram illustrating a de-interlacing sys
tem 100 in accordance With an embodiment of the claimed
video bitstream; extracting a plurality of syntax elements

US 8,165,211 B2
3

4

invention. The de-interlacing system 100 converts interlaced

video signals into non-interlaced video signals by interpolat

cessing continues at signal-checking step 230 if the partition
is medium, i.e.: 8x8 in the example, While processing contin

ing the missing lines in a frame. To begin With, video bit

ues at ?rst edge-based line averaging step 260 for small

stream 101 received from transmitter or storage media is fed
into a video decoding module 110. In an exemplary embodi

partition, i.e.: 4><4 in the example.
At signal-checking step 230, the distribution of the transment, the video bitstream 101 and video decoding module
110 is compatible With the H.264 industrial standard. The
video decoding module 110 decodes the video bitstream 101
and reconstructs the video frames 102. A syntax element
extractor 120 also extracts syntax elements from the video
bitstream 101. In an exemplary embodiment, informationsuch as macroblock types, macroblock partitions, motion
vectors, the distance from the reference frame, the existenceof non-Zero transform coef?cients and the distribution oftransform coef?cients are extracted.

The syntax elements are provided to a decision stage 130

form coef?cients of the macroblock is examined. If the prediction errors of the content of the macroblock are verticallysmooth, Which means that the prediction errors of the mac
roblock are coded by 8x8 transforms and each 8x8 transformed block does not have non-Zero coef?cients in the bot

tom 8x4 area, processing continues at second line averaging

step 240. OtherWise, processing continues at second edge
based line averaging step 250.
At ?rst line averaging step 220 and second line averaging
step 240, line averaging, Which is simple and e?icient forvertically smooth areas, i.e., areas Without vertical aliasing, isdetermined as the mode of de-interlacing for the macroblock.
Which determines the modes of de-interlacing for various
At ?rst edge-based line averaging step 260 and second edge
regions of a video frame. In one exemplary embodiment, eachregion corresponds to a macroblock in a video frame, While
based line averaging step 250, edge-based line averaging,such macroblock is processed in a subsequent interpolation 20 Which has outstanding performance for sharp and consistentedges inside the non-vertically-smooth areas, is determinedstage 150 by a dedicated processing unit (not shoWn). In
as the mode of de-interlacing for the macroblock.
another exemplary embodiment, the decision stage 130 out
FIG. 3 is a How chart for determining the mode of deput decisions for de-interlacing mode as tWo-dimensional
interlacing for inter-coded marcoblocks in the decision stagearrays, also referred hereinafter as 2-D mode maps 103. Each
2-D mode map corresponds to a reconstructed video frame 25 of FIG. 1. At mode-checking step 310, the video coding modeis checked. If the video stream is coded in direct mode or skip
102. The de-interlacing mode, also referred as interpolationmode, processing continues at step 320. Otherwise process
method, for each processing unit (not shoWn) is determineding continues at partition-checking step 330.
based on the values of syntax elements. HoWever, the syntax
At partition-checking step 330, the siZe of the macroblockelements may not necessarily re?ect the real motion, due tothe encoding strategies and the restriction of the standards. It 30 partition is examined. Processing continues at transformchecking step 340 if the macroblock partition is large, i.e.:
is therefore important to select the proper de-interlacing
mode for an image region. In certain situations, Where motion
larger than 8x8 in the exemplary embodiment. Otherwise,
exists but the decision stage 130 determines the de-interlacing
processing continues at step 360.
algorithm other than motion compensation according to the
At transform-checking step 340, it is examined from thesyntax elements from syntax element extractor 120, the pres 35 syntax elements Whether the macroblock is encoded under

ently claimed invention determines complementary motion
compensation as the de-interlacing mode by analyZing thereal motion, such that the interpolation stage 150 can replace

8x8 transform and Whether the prediction errors of the content of the macroblock are vertically smooth. If the macrob
lock is 8x8 transformed and the prediction errors of the con

the non-motion-compensation method With the motion com
tent are also vertically smooth (the concept of vertical
pensation one and accord better With the real motions of the 40 smoothness can be referred back to paragraph 31), processing
continues at step 350. OtherWise, processing continues at step
video sequences.
370.
The reconstructed video frames 102 and corresponding
2-D mode maps 103 are then received by a delayer and
At step 320 and step 350, motion compensation is deter
mined as the mode of de-interlacing for the macroblock. At
re-ordering unit 140. The delayer and re-ordering unit 140
delays each of the reconstructed frames 102 and rearranges 45 ?rst edge based line averaging step 360 and second edge
the same into a sequence of re-ordered frames 104 according
based line averaging step 370, edge-based line averaging isdetermined as the mode of de-interlacing for the macroblock.
to temporal order. The 2-D mode maps 102 are also rear
FIG. 4 is a block diagram illustrating the interpolation
ranged based on the sequence of the corresponding re-or
dered frames into re-ordered 2-D mode maps 105. Both thestage 150 in FIG. 1. In the illustrated embodiment, interpo
reordered frames 104 and the re-ordered 2-D mode maps are 50 lation stage 150 is implemented by parallel processing ofinterpolaters 420 in parallel architecture. Initially, re-ordered
subsequently input to an interpolation stage 150. The interpolation stage 150 de-interlaces the re-ordered frames 104
frames 104 and 2-D mode maps 105 are provided by theaccording to the decisions on corresponding re-ordered 2-D
delayer and re-ordering unit (not shoWn) to a partitioner 410.
The partitioner 410 divide each re-ordered frame 104 intomode maps 105. Consequently, the interpolation stage 150
outputs de-interlaced frames 106 for display by a display 55 image slices 401 based on the number of CPU cores. The 2-D
mode map 105 corresponding to the re-ordered frame 104 is
device (not shoWn).
also partitioned into sliced 2-D mode map 402. Each set of
In one exemplary embodiment, the decision stage 130 andimage slice 401 and sliced 2-D mode map 402 is input to ainterpolation stage 150 canbe implemented independently bycorresponding interpolater 420. The interpolater 420 refers toseparate processing units, including but not limited to digital
60 the decision information on the sliced 2-D mode map 402 andsignal processors, microprocessors, FPGAs and ASICs.
FIG. 2 is a How chart for the decision stage 200 to deter
de-interlaces the image slice 401 With the proper mode. As
mine the mode of de-interlacing for intra-coded marcoblocks
such, different parts of an image ?eld can be de-interlacedin the decision stage of FIG. 1. According to an exemplary
independently under the proper mode. In an exemplary
embodiment, the mode of de-interlacing is chosen from line
embodiment, at partition-checking step 210, the partition of
the macroblock is obtained from the syntax elements and 65 edging, edge-base line edging, motion compensation, andexamined. Processing continues at ?rst line averaging step
complementary motion compensation. After de-interlacing,
220 if the partition is large, i.e.: 16x16 in the example. Pro
each interpolater 420 outputs a respective de-interlaced sliceUS 8,165,211 B256403 Which is sent to a merger 430. The merger then assembles

In an exemplary embodiment, tWo blocks are taken as

the de-interlaced slices 403 according to corresponding coordinate information and generates a de-interlaced frame 106.
FIG. 5 shoWs the scenario, in Which complementary
motion compensation is used, in accordance With an embodi
ment of the claimed invention. The complementary motion

perfectly matched if the transform coef?cients of M are all
Zero as indicated by the coded block pattern (CBP) in the
bitstream.
As the missing ?eld of frame n and the existing ?elds offrames n-1 610 and n+1 630 have the same interlacing parity

compensation (CMCP) according to the presently claimed(i.e., odd or even), the inverse motion vector 651, 653 alWays
points to the existing pixels 613, 631 in frame n-1 610 and
n+1 630. Therefore, both the existing pixels 613, 631 frominvention can be referred as an updating process in the interpolation stage. CMCP is applied to the frames, hereinafter

frames n-1 610 and n+1 630 can be used as reference pixels

referred as target CMCP frames, Which, as restricted by the
bitstreams, are located temporally far from their reference
frames in the frame sequence. For example, target CMCP

to interpolate the missing pixel 623 in frame n 620. In suchsituation, the mean of the respective interpolation values Will

frames can be the P frames 530 in IBBPBBP sequence strucincrease the usage of motion compensation method, Which is

be used as the ?nal interpolation value. The CMCP cantures, Where IBBPBBP notates the sequential order of thesuperior to intra-?eld method and can reduce ?ickers.
FIG. 7 is a How chart representing embodiments of theclaimed method. One embodiment of the claimed method of

relevant I frame, B frames and P frames. In a further exem

plary embodiment, the target CMCP frames can be hierarchi

cal B frames. More accurately speaking, CMCP is especiallydecoding a video bitstream begins With reconstructing 701
adopted When processing units (such as the interpolators insuccessive images from a video bitstream folloWed by
FIG. 4) process the macroblock in target CMCP frames, 20 extracting 703 a plurality of syntax elements from said video
Which is coded in intra mode. According to the How chart in
bitstream. After extracting step 703, the deciding step 705
decides a de-interlacing algorithm from an algorithm set for
FIG. 2, the de-interlacing mode, or interpolation method, iseach image region in a video frame based on said plurality ofdetermined to be intra in the decision stage.

syntax elements folloWed by interpolating step 707 for inter

HoWever, it is common scenario that an intra-coded mac

roblock 532 in the target CMCP frame 530 may contain 25 polating each said image region using said de-interlacing
algorithm or complementary motion compensation andmotion. When the later P frame 530 (Which is the target

complementary motion compensation de-interlaces said
CMCP frame) is far from its reference frame, i.e., the earlier
image region using the inverse of motion vectors extracted
P frame 510, the macroblock 532 in the triangular object 531
cannot ?nd a perfectly matching block in the reference framefrom neighboring frames.
510. This is because the edge of the triangular object 511 has 30
The foregoing description of embodiments of the presentchanged over such a long interval. The encoder has no choice
but to use intra mode to code the macroblock 532. Conseinvention are not exhaustive and any update or modi?cations

to them are obvious to those skilled in the art, and therefore
reference is made to the claims for determining the scope ofquently, the associated processing unit has to select intra-?eldinterpolation method such as line averaging or edge-base line

the present invention.

averaging.

We claim:

Assuming the macroblock 532 actually contains motion, it

1. A method of decoding video bitstream, comprising:reconstructing successive images from a video bitstream;
extracting a plurality of syntax elements from said video

has a perfectly matching block 522 in a previous B frame 520.
HoWever, this B frame 520 cannot be referenced by the P
frame 530 due to a restriction of the video coding standard.

bitstream, Wherein the syntax elements are selected

Under this circumstance, the quality of de-interlacing is actu 40
ally superior if motion compensation is used, as compared to
intra-?eld interpolation. In the decision stage according to thepresently claimed invention, the motion of the macroblock532 is taken into account. Accordingly, CMCP is chosen as

the mode of de-interlacing to acquire better image quality.

45

FIG. 6 depicts the method of complementary motion com

pensation for interpolating missing pixels by reference toexisting pixels in immediately neighboring frames in accor
dance With an embodiment of the claimed invention. For
convenience of illustration, each frame is considered as a line 50

of pixels Which extend in the y direction 602. The x-axis 601
represents the time axis, While frame n-1 610, frame n 620,
frame n+1 63 0 are shoWn in sequential order from left to right.
Frame n 620 is the target CMCP frame, in Which the CMCP
is applied. The horiZontal and vertical coordinates represent 55
the time and line, respectively. Under CMCP, the immedi
ately neighboring frame n-1 610 and frame n+1 630 are usedas the references for de-interlacing frame n 620.
The existing pixels 622, 624 in frame n 620 are used as thereferences by the processing unit M in the frame n-1 610 With 60
the motion vectors MV1 641, 642 (among syntax elements

extracted from the bitstream) to interpolate missing pixels
612, 614. Furthermore, the reference and target blocks are

perfectly matched. Therefore, the missing pixels 621, 623 inframe n 620 can be interpolated from pixels 611, 613 in frame 65
n-1 610 by motion vector 651, 652, Which are the inverse of
MV1 641, 642.

from a macroblock type, a macroblock partition, amotion vector, a distance from a reference frame, exist
ence of non-Zero transform coe?icients, or a distributionof transform coe?icients;
deciding a de-interlacing algorithm from an algorithm set
for each image region in a video frame based on said

plurality of syntax elements, the deciding of the deinterlacing algorithm comprising one of:adopting motion compensation as the de-interlacing
algorithm for inter-coded macroblocks in neither
direct mode nor skip mode, Wherein the macroblock
partition is larger than 8x8, and Wherein the macrob
locks are 8x8 transformed and prediction errors ofcontent of the macroblocks are vertically smooth;

adopting edge-based line averaging as the de-interlacing
algorithm for inter-coded macroblocks in neither
direct mode nor skip mode, Wherein the macroblock

partition is larger than 8x8, and Wherein prediction
errors of content of the macroblocks are neither 8x8transformed nor vertically smooth; or

adopting edge-based line averaging as the de-interlacing
algorithm for inter-coded macroblocks in neither
direct mode nor skip mode, Wherein the macroblock
partition is not larger than 8x8; andinterpolating each said image region using said de-interlacing algorithm and complementary motion compen
sation; Wherein said complementary motion compensa
tion de-interlaces said image region using an inverse ofUS 8,165,211 B2
8

7

a syntax element extractor for extracting a plurality of

motion vectors extracted from a bitstream clip repre

senting neighboring frames.

syntax elements from said video bitstream, Wherein thesyntax elements are selected from a macroblock type, amacroblock partition, a motion vector, a distance from a

2. The method of decoding video bitstream according toclaim 1, Wherein said complementary motion compensation
de-interlaces said image region using the inverse of motion

reference frame, existence of non-Zero transform coef?cients, or a distribution of transform coe?icients;

vectors extracted from neighboring frames, Wherein saidmotion vectors point to a current frame from saidneighboring
frames.

a decision stage unit for deciding a de-interlacing algorithm from an algorithm set for each image region in avideo frame based on said plurality of syntax elements,

3. The method of decoding video bitstream according to

the deciding of the de-interlacing algorithm comprisingclaim 1, Wherein said algorithm set further comprises one ormore algorithms selected from the group consisting of line

one of:adopting motion compensation as the de-interlacing
algorithm for inter-coded macroblocks in neither

averaging, edge-based line averaging, and motion compen
sation.
4. The method of decoding video bitstream according to 15
claim 1, further comprising storing in an array the results ofdeciding a de-interlacing algorithm from an algorithm set foreach of said image region.
5. The method of decoding video bitstream according toclaim 1, Wherein said deciding a de-interlacing algorithm 20
comprising adopting line averaging as the de-interlacing

algorithm for intra-coded macroblocks having partition

locks are 8x8 transformed and prediction errors ofcontent of the macroblocks are vertically smooth;

adopting edge-based line averaging as the de-interlacing
algorithm for inter-coded macroblocks in neither
direct mode nor skip mode, Wherein the macroblock

partition is larger than 8x8, and Wherein prediction
errors of content of the macroblocks are neither 8x8transformed nor vertically smooth; or

16x16 or for intra-coded macroblocks having partition 8x8,

adopting edge-based line averaging as the de-interlacing

Wherein prediction errors of content of the macroblocks arevertically smooth.

direct mode nor skip mode, Wherein the macroblock

partition is larger than 8x8, and Wherein the macrob

25

6. The method of decoding video bitstream according toclaim 1, Wherein said deciding a de-interlacing algorithm
comprising adopting edge-based line averaging as the deinterlacing algorithm for intra-coded macroblocks having
partition 4x4 or for intra-coded macroblocks having partition 30
8x8, Wherein prediction errors of content of the macroblocks
are not vertically smooth.

algorithm for inter-coded macroblocks in neither
direct mode nor skip mode, Wherein the macroblock
partition is not larger than 8x8; andinterpolaters for interpolating each said image region using
said de-interlacing algorithm and complementary
motion compensation, Wherein said complementary
motion compensation de-interlaces said image region
using an inverse of motion vectors extracted from a

bitstream clip representing neighboring frames.

7. The method of decoding video bitstream according to
1 0. The apparatus of decoding video bitstream according toclaim 1, Wherein said deciding a de-interlacing algorithm
claim
9, Wherein said complementary motion compensation
comprising adopting motion compensation as the de-interlac 35
de-interlaces said image region using the inverse of motion
ing algorithm for inter-coded macroblocks under direct mode
vectors extracted from neighboring frames, Wherein saidor skip mode.

8. The method of decoding video bitstream according toclaim 1, additionally comprising receiving video bitstream
Which is coded under video standards selected from the group 40

consisting ofAVS and H.264.
9. An apparatus for decoding video bitstream, comprising:a decoder for reconstructing successive images from a

video bitstream;

motion vectors point to a current frame from saidneighboring
frames.

1 1. The apparatus of decoding video bitstream according toclaim 9, Wherein said algorithm set further comprises analgorithm selected from the group consisting of line averag

ing, edge-base line averaging, and motion compensation.
*

*

*

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*