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International Journal of Signal Processing, Image Processing and Pattern Recognition
Vol. 6, No. 3, June, 2013


17

Efficient Video Stabilization Technique for Hand Held Mobile
Videos


Paresh Rawat
1
and Jyoti Singhai
2

1
Department of Electronics & Communication Engineering,
Truba College of Science &Technology Bhopal, India
2
Department of Electronics Engineering
Maulana Azad National Institute of Technology, Bhopal, India
1
[email protected],
2
[email protected]
Abstract
Majority of the videos that have been captured by mobile cameras are suffering from low
quality due to either low end manufacturing designs or complicated operating environments
and untrained users. Thus videos taken by hand held mobile cameras tend to suffer from
different undesired slow motions that cause annoying shaky motion and jitter. It is desirable
to stabilize the video sequence by removing the undesired motion between the successive
frames. Current methods are applicable to only specific camera motion models; hence having
limitation to process gorse motion. In this paper an efficient video stabilization algorithm for
hand held camera videos has been proposed. The proposed algorithm uses differential global
motion estimation with Taylor series expansion to improve the estimation efficiency. Affine
motion model has been assumed to define the inter-frame error between consecutive frames.
Motion vectors have been estimated analytically by solving the derivatives of the inter-frame
error. After motion estimation Gaussian kernel filtering has been used to smoothen out
estimated motion parameters. Inverse rotation smoothening has been applied to remove the
rotation effect from the smoothed transformation chain. This has led to reduced accumulation
error and minimizes the missing image area significantly. The performance of the proposed
algorithm has been tested on real time videos and compared with existing algorithm.

Keywords: Video stabilization, differential motion estimation, Taylor series expansion,
Gaussian Kernel filtering, motion smoothing

1. Introduction
Inventions of hand-held devices, such as digital camcorders and cell phones with video
capturing capabilities, have enabled everyday users to capture high-quality videos. The video
imagery can be processed as a sequence of still images, where each frame is processed
independently. However, the utilization of existing temporal redundancy by means of
multiframe processing enables us to develop more effective algorithms, such as video
stabilization. Hence video stabilization is becoming an indispensable technique in improving
the design of these mobile cameras. Stabilization is a video processing technique to enhance
the quality of input video [1, 7]. Stabilization is achieved by synthesizing a new stabilized
video sequence; by estimating and removing the undesired inter frame motion between the
successive frames. The video stabilization can either be achieved by hardware or post image
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processing approach. Hardware approach can be further classified as mechanical or optical
stabilization. Mechanical stabilizer uses gyroscopic sensor to stabilize entire camera. Optical
stabilization activates an optical system to adjust camera motion sensors. This approach is
expensive and also has limitation to process different kind of motions simultaneously. In the
image post processing algorithm, there are typically three major stages constituting a video
stabilization process viz. camera motion estimation, motion smoothing or motion
compensation, and mage warping. There are various algorithms proposed for stabilizing
videos taken under different environment from different camera systems by modifying these
three stages.
The development of video stabilization can be traced back by the work done in the field of
motion estimation. Various algorithms have been proposed to reduce the computational
complexity and to improve the accuracy of the motion estimation. The efficiency of the
stabilization depends on the accuracy of the motion estimation and optical flow methods.
Horn and Schunck (HS) [17] is widely used optical flow method. But it only computes the
slow motion and provides the motion vectors in one direction only. The paper discusses the
optical flow performance of original and modified HS method using 1D separable filter to
find the temporal derivatives.
The global motion estimation can either be achieved by feature based approaches [2-5] or
direct pixel based approaches [1, 7-9]. The feature-based approaches are although faster than
direct pixel based approaches, but they are more prone to local effects and their efficiency
depends upon the feature point selection [1]. Thus they have limited performance for
unintentional motion. The direct pixel based approach makes optimal use of the information
available in motion estimation and image alignment, since they measure the contribution of
every pixel in the video frame. Matsushita et al., [1], in 2006 proposed the direct pixel based
full frame video stabilization approach using hierarchical differential motion estimation with
Gauss Newton minimization. After motion estimation, motion inpainting is used to generate
full frame video. This method gave good results in most videos; except in those cases when
large portion of video frame is covered by a moving object, since this large motion makes the
global motion estimation unstable. In this paper a modified video stabilization algorithm for
hand held camera videos is proposed. The proposed algorithm uses Taylor series expansion
instead of Gauss Newton minimization. Property of Taylor series is that it converges for each
value of motion vectors and hence provides stable global motion estimation. After motion
estimation Gaussian kernel filtering is used, only to smoothen out estimated motion
parameters. This reduces the accumulation error and minimizes missing image area
significantly.
In this paper existing algorithms used to stabilize the different type of video sequences are
discussed in Section 2. In Section 3 proposed hierarchical differential motion estimation and
Gaussian kernel filtering for motion smoothing are discussed. The results obtained with the
proposed video stabilization algorithm are discussed in Section 4.

2. Reviews of Video Stabilization Algorithms
Video stabilization can be broadly classified as mechanical stabilization, optical
stabilization and image post processing stabilization. Mechanical video stabilization systems
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based on vibration feedback via sensors like gyros accelerometers etc. have been developed in
the early stage of camcorders [22]. Optical image stabilization, which has been developed
after mechanical image stabilization, employs a prism or moveable lens assembly that
variably adjusts the path length of the light as it travels through the camera’s lens system [23].
Mechanical and optical stabilization methods are unsuitable for small camera modules
embedded in mobile phones due to lack of compactness and the cost associated with
it. Hence digital video stabilizers with lesser complexity and fast response are more
suitable for stabilizing the hand held mobile camera video.
The digital video stabilization methods can be broadly classified as direct pixel based
methods [1, 7, 9, 15], and feature based methods as [2-5]. The efficiency of the motion
estimation technique depends on the optical flow method used. Two most widely used optical
flow methods are Horn and Schunck (HS) [17] and Lucas Kanade [18]. The performance of
the optical flow methods depends on the method used to find the temporal derivatives. Hany
Farid [7] used the 1D separable kernel filters to find the temporal derivatives. The majority of
today’s methods strongly resemble the original formulation of HS which is a global method.
They combine a data term that assumes constancy of some image property with a spatial term
that models how the flow is expected to vary across the image. An objective function
combining these two terms is then optimized. On the other hand Lucas Kanade method is a
local optical flow method. But these methods were initially used for the slow motion videos.
Various feature based approaches are proposed for video stabilization. Chang et al., [2]
presented a feature tracking approach based on optical flow, considering the fixed grid of
points in the video. But this approach was developed for a specific motion model [2]. Rong
Hu, et al., [3] in 2007 proposed an algorithm to estimate the global camera motion with SIFT
features. These SIFT features have been proved to be affine invariant and used to remove the
intentional camera motions. Junlan Yang et al., [4] in 2009 used SIFT feature points and
particle filtering framework to estimate the global motion between two frames. To estimate
intentional motion from accumulative motion Kalman filter is used. Derek Pang et al., [5] in
2010 proposed the video stabilization using Dual-Tree complex wavelet transform (DT-
CWT). This method uses the relationship between the phase changes of DT-CWT and the
shift invariant feature displacement in spatial domain to perform the motion estimation.
Optimal Gaussian kernel filtering is used to smoothen out the motion jitters. This phase based
method is immune to illumination changes between images, but this algorithm is
computationally complex. R. Szeliski, [6] in 2006 presented a survey on image alignment to
explain the various motion models, and also presented a good comparison of pixel based
direct and feature based methods of motion estimation. The efficiency of the feature based
methods depends upon the feature point’s selection [6]. The features would often be
distributed unevenly over the images, hence feature based methods may fail to match image
pairs that should have been aligned. The feature based methods may have probability to get
confused in regions that were either too textured or not textured enough.
Direct pixel based methods use each pixel in the frame to estimate the global motion. Hany
Farid and J.B. Woodward in 1997 [7], modelled motion between video frames as a global
affine transform and parameters are estimated by hierarchical differential motion algorithms.
Temporal mean and median filters were applied to this stabilized video sequence for
enhancing the video quality. But they have not implemented the motion smoothening or
compensation algorithms. Olivier Adda, et al., [8] in 2003 presented various motion
estimation and compensation algorithms for video sequences. They suggested the uses of
hierarchical motion estimation with gradient descent search to converge the parameters. But
the method was slow and complex.
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Matsushita et al., [1], in 2006 proposed the direct pixel based full frame video stabilization
method with motion inpainting. They achieved video stabilization by assuming an affine
motion model between each pair of frame to represent the inter frame error between adjacent
frames. Then an ‘L’ level Laplacian image pyramid is constructed and inter-frame error is
estimated using hierarchical differential motion estimation which leads to enhanced accuracy,
robustness and improved efficiency [15-16]. Estimation process involves SSD minimization
with Gauss Newton minimization, which uses a first order expansion of the individual error
quantities before squaring. The limitation of this method is that it strongly relies on the result
of global motion estimation which may become unstable when a moving object covers large
amount of image area [1]. For fast moving objects neighbouring frames will not be warped
correctly, and there will be visible artefacts at the boundaries. The convergence ability of the
Gauss Newton minimization is also limited.
Feng Liu et al., [9] in 2009 proposed an algorithm of content preserving warps for 3D
video stabilization for hand held cameras. The key insight of the work is that for the purposes
of video stabilization, small shift in viewpoint can be faked by a carefully constructed content
preserving warp, but result is not physically accurate. The major limitation of this approach
compared to 2D video stabilization is that it first requires running structure from motion, and
method is also more brittle and heavy weight. R. Szeliski [6] suggested that, for matching the
sequential frames in a video direct pixel based methods can be used. Direct methods make
optimal use of the information available in image alignment and provide a very accurate
alignment results. It is because they use each pixel in the frame to estimate the global motion.
However, the computational load is heavy and convergence range is also limited.
After estimation to smoothen the undesired camera motion in the global transformation
chain, various approaches have been proposed [10-13]. Buehler et al., [10] proposed Image
based rendering algorithm to stabilize video sequence. The camera motion was estimated by
non-metric algorithm, and then image-based rendering was applied to smoothed camera
motion. Method performs well only with simple and slow camera motion videos and was
unable to fitter motion models to complex motion as in the case of hand held camera videos.
Litvin et al., [11] applied the probabilistic methods using Kalman filter to smoothen camera
motion. This method produced very accurate results in most of the cases, but it required
tuning of camera motion model parameters to match with the type of camera motion in the
video. Matsushita et al., [1] developed an improved method called Motion inpainting for
reconstructing undefined regions and to smoothen camera motion Gaussian kernel filtering
was used effectively.

3. Proposed Video Stabilization Algorithm
In this paper an efficient video stabilization method is proposed for hand held mobile
phone cameras. The proposed method uses the differential global motion estimation with the
combination of the Gaussian kernel filtering for motion smoothing. The video sequences are
captured from mobile phone camera in different environment.

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Figure 1. Proposed Algorithm for Hand Held Mobile Video Stabilization
The motion is first detected using the optical flow method and then motion vectors are
estimated. The proposed algorithm improves the efficiency and convergence rate of the global
motion estimation. This is achieved by using Taylor series expansion [7], instead of Gauss
Newton minimization algorithm as proposed by Matsushita et al., [1], for differential motion
estimation. The use of Taylor series reduces the nonlinear error function to linear differential
equation.
The linear differential equation can be solved analytically, hence reduces computational
complexity. The proposed algorithm is explained in Figure 1, which consists of two stages
motion estimation and motion smoothening. Motion estimation is explained in Section 3.1, in
this stage every frame of video sequence is decomposed into L level Laplacian image
pyramid. The motion between successive frames is estimated using first order Taylor series
expansion. The temporal derivatives are determined by 1-D separable filters. In the presence
of fast moving object in the frames, use of the bi-cubic interpolation for warping the pyramid
levels minimizes the visible artefacts at the boundaries. In Section 3.2 motion smoothening is
explained using Gaussian kernel filtering by smoothening estimated transform parameters to
minimize the missing image areas. Then inverse rotation filtering is applied on smoothened
frame to generate the window based completion method to reduce the overall accumulation
error.

3.1. Motion Estimation
The motion of any pixel between two consecutive frames can be estimated either by global
motion or by local motion. The global motion occurs due to camera motion but in local
motion object in the scene is in motion. In case of a non-stationary camera or for small
motion of the object, motion is estimated by a global motion model. The direct method of
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global motion estimation makes optimal use of the information available in image alignment,
since they measure the contribution of every pixel in the video frame. For matching
sequential frames in a video, the direct approach can usually be made to work [6]. The
differential global motion estimation has proven highly effective at computing inter-frame
motion [7, 14]. The method used in this paper for motion estimation is similar to that of the
[7], the motion between two sequential frames, and is modelled with
a 6-parameter affine transform as in [1, 7, 20, and 21]. The major advantage of using the
affine model lies in the fact that for global motion, the affine parameters at every location
should be the same. Therefore, instead of keeping track of every motion vector, the sum of
square difference (SSD) error between two images can be described by a single affine
transformation as given by eq. (1).
∑[









]



Where





and

represents the affine rotation matrix , and

and

the
translation vector .
(








) (




) (2)
Where denotes a user specified region of interest here it is the entire frame.
To improve the performance of the motion estimation a hierarchical global estimation is
used [1]. An -level Gaussian pyramid is built for each frame pair of frames
and . The motion estimated at each pyramid level is used to warp the
frame at the next higher level , until the finest level of the pyramid is reached (the full
resolution frame is at ). Large motions are estimated at coarse level by warping using
bicubic interpolation and refining iteratively at each pyramid level. If the estimated motion at
pyramid level is









and

, then the original frame should be warped with the
affine matrix and the translation vector is given by (3).
After working at each level of the pyramid, the original frame will have to be repeatedly
warped according to the motion estimated at each pyramid level. Two affine matrices

and


and corresponding translation vectors
1
and
2
are combined as in equation (3), which is
equivalent to applying

and
1
followed by

and
2.





, and






To simplify the minimization, this error function (1) is approximated by using a first-order
truncated Taylor series expansion as in method of Hany Farid [7]. The quadratic error
function is now linear in its unknowns, m and can therefore be minimized analytically by
differentiating with respect to m as,



∑[

]


Where the scalar k and vector

are given as








(











)

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By setting the result equal to zero, and solving for m yields eq. (5).
[∑



]

[ ∑

]


a) With Horn and Schunck method(17] b) With proposed method
Figure 2. Comparison of the motion vectors for car video frame 15 and 16
The temporal derivatives are calculated by using 1-D separable kernel filters as in [7]. The
advantage of using the separable kernel filter of is that the computation is reduced to
multiplication from multiplication. Hence 1-D separable filters are used to
reduce the computation complexity. The comparison of the optical flow of the original
derivatives used by Horn and Schunck [17] and the derivatives with separable kernel are
shown in Figure 2. Although estimating the global motion, but the motion vectors may be in
different direction at different locations. It is clear that use of separable kernel for calculating
the temporal derivatives performs better than conventional method because they are able to
represent motion vectors more accurately.

3.2. Motion Smoothening
The proposed video stabilization algorithm uses Gaussian kernel filtering to smooth the
undesired camera motion after motion estimation and to remove accumulation error. In order
to avoid the accumulation error due to the cascade of original and smoothened transformation
chain, displacement among the neighbor frames is smoothened to generate a

compensation
motion. The coordinate transformed from frame to , are denoted by the transform


, as
used by Matsushita et al. [1]. The neighbor frame is given as,



The idea of Gaussian smoothing is to use this 2-D distribution as a point spread function
(PSF), and this is achieved by convolution.The compensation motion transform can be
calculated as;









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Where means convolution operator and is the Gaussian kernel given as









The motion compensated frames



can be warped from the original frame

as;








The use of large Gaussian kernel might lead to the blurring effects and small Gaussian
kernel may not effectively remove the high frequency camera motion. Hence an optimal value
of Gaussian kernel is selected. The parameter of Gaussian filter is set to as √ [1]. The
σ value for Gaussian kernel should not be greater than 2.6. Hence the kernel parameter k
should be either less than or equal to 6. Use of Gaussian kernel filtering minimizes the
missing image areas.

3.2.1. Rotation Smoothing
The rotation effect caused due to the smoothed transformation chain is removed by rotating
the frame by rotation angles. The rotation angles

and



are calculated by using the
smoothed affine parameters m
2
and m
3


as













After calculating the rotation angles, the frame is rotated in reverse direction by these
angles to remove rotation effects.





Where and are the inverse rotation factors. By using this inverse rotation
factors the missing image areas are minimized.

4. Results and Discussion
Performance of the proposed video stabilization algorithm is tested on sixteen real time
video sequences generated by Nokia (6303) mobile phone camera. The frame rate was 15
frames per second with the resolution of 176 x 144. The performance for two distinct videos
viz. Corridor and Highway are illustrated in this paper for comparison with other algorithms.
The Corridor video shown in Figure 3(a) is a slow motion video and Highway video shown in
Figure 4(a) is a video with large object motion in static scene. The results of the optical flow
methods of HS derivatives [17] and for 1D separable filters are presented for the case of large
moving object in the scene. The difference of the original and estimated frames is used
motion for the performance evaluation as in Figure 5. It is clear that proposed method is able
to estimate more precise motion vectors and thus gave better results than basic HS method.
To stabilize the motion between each pair of frames in these videos global motion
estimation has been used. To verify the performance of motion estimation, the inter frame
error between original input frames were compared with, inter frame error after motion
estimation with Mean filtering, Median filtering, Bicubic interpolation and Spline
interpolation methods. The frame to frame comparison for MSE and SNR for original input
and motion estimated video sequences are shown in Table 1 and Table 2 respectively.
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Comparisons are shown for 10 consecutive frames having the maximum motion in the given
two videos.


Figure 3. Performance of Proposed Algorithm for every 5
th
Frame for Corridor
Video


Figure 4. Performance of Proposed Algorithm for Every 5
th
Frame for Highway
Video

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Table 1. Comparison of MSE for Input Video and Motion Estimated Video
Video Mean Square Error f1,f2 f2,f3 f3,f4 f4,f5 f5,f6 f6,f7 f7,f8 f8,f9 f9,f10
Peak to
Peak
diff.
H
I
G
H
W
A
Y

Original video Before
Stabilization
23.88 29.25 31.39 29.10 29.77 34.05 41.13 48.52 53.0 29.12
After
Stabilization
With simple
mean filter
16.98 21.79 23.95 22.12 23.72 27.99 35.31 42.96 47.69 31.01
With simple
median filter
15.85 20.52 22.67 21.0 22.83 27.06 34.54 42.26 47.11 31.26
with spline
interpolation
8.45 7.79 8.448 13.38 13.88 7.052 30.08 20.58 20.7 23.05
with Proposed
bicubic
interpolation
20.02 16.67 18.33 23.93 25.88 18.58 32.53 23.98 24.5 17.19
C
O
R
R
I
D
O
R
Original video Before
Stabilization
15.78 10.87 8.35 13.93 21.99 25.26 31.36 22.4 20.06 23.01

After
Stabilization
With simple
mean filter
11.19 7.28 5.36 10.18 17.78 21.35 28.03 18.12 15.59 20.75
With simple
median filter
10.53 6.97 5.09 9.79 17.12 20.73 27.55 17.45 14.92 22.46
with spline
interpolation
7.16 7.10 7.26 7.64 4.68 9.29 11.38 14.87 5.59 9.28
with
Proposed
bicubic
interpolation
21.05 21.62 22.93 24.89 22.12 27.14 27.28 27.81 23.68 6.76

Table 2. Comparison of SNR for Input Video and Motion Estimated Video
Video Signal to Noise Ratio f1,f2 f2,f3 f3,f4 f4,f5 f5,f6 f6,f7 f7,f8 f8,f9 f
9
,f
10

Peak
to
Peak
Diff
H
I
G
H
W
A
Y

Original video Before
Stabilization
5.68 4.64 4.34 4.71 4.64 4.06 3.37 2.86 2.67 3.01
After
Stabilization
With simple
mean filter
7.99 6.23 5.69 6.19 5.82 4.94 3.93 3.23 2.97 5.02
With simple
median filter
8.56 6.62 6.00 6.52 6.05 5.10 4.02 3.29 3.00 5.56
with spline
interpolation
16.07 17.42 16.13 10.25 9.95 19.59 4.61 6.77 6.86 14.98
with bicubic
interpolation
6.78 8.15 8.35 5.73 5.33 7.43 4.27 5.79 5.78 3.98
C
O
R
R
I
D
O
R
Original video Before
Stabilization
9.09 13.22 17.13 10.3 6.56 5.58 4.60 6.62 7.44 8.62
After
Stabilization
With simple
mean filter
12.82 19.75 26.7 14.08 8.11 6.81 5.14 8.18 9.57 21.56
With simple
median filter
13.61 20.62 28.07 14.64 8.42 7.01 5.23 8.49 10 15.39
with spline
interpolation
20.06 20.22 19.69 18.8 30.81 15.65 12.67 9.97 26.7 20.04
with bicubic
interpolation
6.81 6.65 6.24 5.76 6.52 5.36 5.18 5.33 6.30 1.63

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From Table 1 and 2 it can be evaluated that with proposed algorithm using a Bicubic
interpolation MSE and SNR are more stabilized, while variation in MSE are very large with
simple mean, median filters and Spline interpolation. It is clearly seen form Table 1 and 2 that
minimum peak to peak difference of MSE is 17.19 for Highway video and 6.76 for Corridor
video and minimum peak to peak difference of SNR is 3.98 for Highway video, and 1.63 for
Corridor video which are obtained with proposed method using bicubic interpolation.


Figure 5.Comparison of Optical Flow Method a) Original Frame b) Estimated
Frame c) Difference of Frames for Horn and Schunck Derivatives [17] and d)
Difference of Frames for Proposed Method


a) Input Frame Used by Feng Liu. [9] available at www.cs.wisc.edu/graphics/Gallery/Warp

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b) Result of 2D Stabilization by Feng Liu. [9] with trimmed border area


c) Result of 2D Stabilization with proposed method
Figure 6. Comparison of Proposed 2D Stabilization Algorithm with Feng Liu [9]


Figure 7. X Translation Before and After Motion Smoothening for Corridor
Video
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Figure 8. Y Translation Before and After Motion Smoothening for Corridor
Video


Figure 9. X Translation Before and After Motion Smoothning for Highway Video


Figure 10. Y Translation Before and After Motion Smoothning for Highway
Video
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The accumulation error due to motion estimation has been minimized by using Gaussian
kernel filtering for motion smoothening, to stabilize undesired translation in X and Y
direction. Figure 7, 8, 9 and 10 shows stabilized translation in X and Y directions for 100
frames, before and after motion smoothening for Corridor and Highway video sequences. It
can be seen that there is significant reduction in the undesired X and Y translations with the
proposed method. Finally the rotation effects are removed by inverse filtering the smoothned
affine parameters. Final stabilized results for the every 5
th
frame of coorridor and highway
videos are presented in Figure 3(c) and 4(c).
Proposed method is also tested on the videos used by Feng Liu [9], as shown in Figure 6.
These videos are available in public domain of www.cs.wisc.edu/graphics/Gallery/Warp and
are used for evaluation and comparison of proposed algorithm with latest existing work. As
seen in Figure 6(b) that results of 2D stabilization by Liu. [9] method are slightly trimed at the
boundaries of the frame, but proposed method generates full frame results with very small
missing areas as shown in Figure 6(c).

5. Conclusion
In this paper a video stabilization algorithm for hand held camera videos is proposed. The
results obtained with the proposed algorithm shows the stabilized motion in X and Y direction
after motion estimation and compensation. The use of Taylor series improves the
convergence rate and increases the efficiency of the motion estimation. To calculate the
temporal derivatives 1-D separable filters are used which reduces the computation cost. The
inter frame error between original input frames are compared with, inter frame error after
motion estimation with mean filtering, median filtering, bicubic interpolation and spline
interpolation. The method gives best stabilization with bicubic interpolation. It is found that
peak to peak variation in MSE is reduced from 30 to 12 for Highway video and 23 to 7 for
Corridor video with sequence of 10 successive frames. After motion estimation Gaussian
kernel filtering is used for motion smoothening and finally the rotation effects are eliminated
using the smoothed affine parameters and inverse rotation filtering. Method is capable of
reducing the missing image areas significantly. There are few missing areas in the results as
shown in Fig 3 and 4. In future these missing areas can be filled up to generate the full frame
stabilized videos using video completion algorithm.

Acknowledgements
Authors especially want to acknowledge Mr. Feng Liu, and expresses thanks to made input
videos globally available, and also grateful to D. P. Biswari for giving his valuable guidance
time to time. Author also expresses sincere thanks to Dr.Ramakant Bharadwaj Prof. Truba
Bhopal, for his expertise to make us learn the mathematics involved with research. Authors
are grateful to everyone who have supported for our research work.


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International Journal of Signal Processing, Image Processing and Pattern Recognition
Vol. 6, No. 3, June, 2013


32

Authors

Prof. Paresh Rawat
Designation: Assistant Professor
B.E. 2000, M Tech, Ph. D* (Pursuing)





Dr. Jyoti Singhai
Designation: Associate Professor
Qualification: B.E., M. Tech., Ph. D
Research areas: Video & Image Processing


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