• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.11 no.9
• /
• pp.4527-4548
• /
• 2017

This paper proposes a method to generate panoramic images by combining conventional feature extraction algorithms (e.g., SIFT, SURF, MPEG-7 CDVS) with sensed data from inertia sensors to enhance the stitching results. The challenge of image stitching increases when the images are taken from two different mobile phones with no posture calibration. Using inertia sensor data obtained by the mobile phone, images with different yaw, pitch, and roll angles are preprocessed and adjusted before performing stitching process. Performance of stitching (e.g., feature extraction time, inlier point numbers, stitching accuracy) between conventional feature extraction algorithms is reported along with the stitching performance with/without using the inertia sensor data. In addition, the stitching accuracy of video data was improved using the same sensed data, with discrete calculation of homograph matrix. The experimental results for stitching accuracies and speed using sensed data are presented in this paper.

• Journal of Broadcast Engineering
• /
• v.24 no.6
• /
• pp.965-973
• /
• 2019

In this paper, Stereo 4K@60fps 360 VR real-time video capture system which consists of video stream capture, video encoding and stitching module is been designed. The system captures stereo 4K@60fps 360 VR video by stitching 6 of 2K@60fps stream which are captured through HDMI interface from 6 cameras in real-time. In video capture phase, video is captured from each camera using multi-thread in real-time. In video encoding phase, raw frame memory transmission and parallel encoding are used to reduce the resource usage in data transmission between video capture and video stitching modules. In video stitching phase, Real-time stitching is secured by stitching calibration preprocessing.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.39C no.10
• /
• pp.957-966
• /
• 2014

Video Stabilization For Vehicular Applications Is An Important Method Of Removing Unwanted Shaky Motions From Unstable Videos. In This Paper, An Improved Video Stabilization Method With Image Stitching Has Been Proposed. Scale Invariant Feature Transform (Sift) Matching Is Used To Calculate The New Position Of The Points In Next Frame. Image Stitching Is Done In Every Frame To Get Stabilized Frames To Provide Stable Video As Well As A Better Understanding Of The Previous Frame'S Position And Show The Surrounding Objects Together. The Computational Complexity Of Sift (Scale-Invariant Feature Transform) Is Reduced By Reducing The Sift Descriptors Size And Resticting The Number Of Keypints To Be Extracted. Also, A Modified Matching Procedure Is Proposed To Improve The Accuracy Of The Stabilization.

• Journal of Digital Convergence
• /
• v.16 no.2
• /
• pp.335-341
• /
• 2018

This study is a study on effective stitching technique for video recorded by using a dual-lens $360^{\circ}$ camera composed of two fisheye lenses. First of all, this study located a problem in the result of stitching by using a bundled program. And the study was carried out, focusing on looking for a stitching technique more efficient and closer to perfect by comparatively analyzing the results of stitching by using Autopano Video Pro and Autopano Giga, professional stitching program. As a result, it was shown that the problems of bundled program were horizontal and vertical distortion, exposure and color mismatch and unsmooth stitching line. And it was possible to solve the problem of the horizontal and vertical by using Automatic Horizon and Verticals Tool of Autopano Video Pro and Autopano Giga, problem of exposure and color by using Levels, Color and Edit Color Anchors and problem of stitching line by using Mask function. Based on this study, it is to be hoped that $360^{\circ}$ VR video content closer to perfect can be produced by efficient stitching technique for video recorded by using dual-lens $360^{\circ}$ camera in the future.

• Journal of Broadcast Engineering
• /
• v.25 no.5
• /
• pp.685-697
• /
• 2020

Immersive media videos, such as panorama and 360-degree videos, must provide a sense of realism as if the user visited the space in the video, so they should be able to represent the reality of the real world. However, in panorama and 360-degree videos, objects appear to overlap or disappear due to parallax between cameras, and such parallax distortion may interfere with immersion of the user's content. Accordingly, although many video stitching algorithms have been proposed to overcome parallax distortion, parallax distortion still occurs due to the low performance of the Object detection module and limitations of the Seam generation method. Therefore, this paper analyzes the limitations of the existing video stitching technology and proposes a method for detecting and correcting parallax distortion of video stitching using the LDPM (Local Differential Pixel Mean) image evaluation method that overcomes the limitations of the video stitching technique.

• Journal of Broadcast Engineering
• /
• v.22 no.1
• /
• pp.51-61
• /
• 2017

This paper proposes a method to generate panoramic images by combining conventional feature extraction algorithms (e.g., SIFT, SURF, MPEG-7 CDVS) with sensed data from an inertia sensor to enhance the stitching results. The challenge of image stitching increases when the images are taken from two different mobile phones with no posture calibration. Using inertia sensor data obtained by the mobile phone, images with different yaw angles, pitch angles, roll angles are preprocessed and adjusted before performing stitching process. Performance of stitching (e.g., feature extraction time, inlier point numbers, stitching accuracy) between conventional feature extraction algorithms is reported along with the stitching performance with/without using the inertia sensor data.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.39C no.6
• /
• pp.503-511
• /
• 2014

In this paper, a novel, real-time video stitching algorithm in an H.264/AVC compressed domain is proposed. This enables viewers to watch multiple video contents using a single device. The basic concept of this paper is that the server is asked to combine multiple streams into one bit-stream based in a compressed domain. In other words, this paper presents a new compressed domain combiner that works in boundary macroblocks of input videos with re-calculating intra prediction mode, intra prediction MVD, a re-allocation of the coefficient table, and border extension methods. The rest of the macroblocks of the input video data are achieved simply by copying them. Simulation experiments have demonstrated the possibility and effectiveness of the proposed algorithm by showing that it is able to generate more than 103 frames per second, stitching four 480p-sized images into each frame.

• Journal of Broadcast Engineering
• /
• v.24 no.1
• /
• pp.142-152
• /
• 2019

There is growing interest in ultra-high-resolution content that gives a more realistic sense of presence than existing broadcast content. However, in order to provide ultra-high-resolution contents in existing broadcast services, there are limitations in view angle and resolution of the image acquisition device. In order to solve this problem, many researches on stitching, which is an image synthesis method using a plurality of input devices, have been conducted. In this paper, we propose method of dynamic object based video stitching using minimal error seam in order to overcome the temporal invariance degradation of moving objects in the stitching process of horizontally oriented videos.

• ETRI Journal
• /
• v.44 no.1
• /
• pp.62-72
• /
• 2022

In this study, we propose a multi-GPU-based 8KVR stitching system that operates in real time on both local and cloud machine environments. The proposed system first obtains multiple 4 K video inputs, decodes them, and generates a stitched 8KVR video stream in real time. The generated 8KVR video stream can be downloaded and rendered omnidirectionally in player apps on smartphones, tablets, and head-mounted displays. To speed up processing, we adopt group-of-pictures-based distributed decoding/encoding and buffering with the NV12 format, along with multi-GPU-based parallel processing. Furthermore, we develop several algorithms such as equirectangular projection-based color correction, real-time CG overlay, and object motion-based seam estimation and correction, to improve the stitching quality. From experiments in both local and cloud machine environments, we confirm the feasibility of the proposed 8KVR stitching system with stitching speed of up to 83.7 fps for six-channel and 62.7 fps for eight-channel inputs. In addition, in an 8KVR live streaming test on the 5G MEC/cloud, the proposed system achieves stable performances with 8 K@30 fps in both indoor and outdoor environments, even during motion.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.40 no.7
• /
• pp.1387-1394
• /
• 2015

Along with the development of network transmission technology, the IPTV market is growing in fast pace. Additionally the UHD resolution broadcasting system along with user experience (UX) that provides better service to user has attracted attention recently since there are not enough research has been done with differentiated the UX that can enhance the UX yet. Therefore we proposed a low complexity syntax level image stitching implementation technique that run with multi-view services, which makes possibility to view multiple channel or video contents on the screen at the same time. Simulation results have demonstrated the liability and effectiveness of the proposed algorithm by showing that capability of generating more than 80 frames per second by stitching four Full-HD size videos into UHD frame.