HEVC based Mixed-resolution Stereo Video Coding for Low Bitrate Transmission

This paper presents a mixed resolution stereo video coding model for High Efficiency Video Codec (HEVC). The challenging aspects of mixed resolution video coding are enabling the codec to encode frames with different frame resolution/size and using decoded pictures having different frame resolution/size for referencing. These challenges are further enlarged when implemented using HEVC, since the incoming video frames are subdivided into coding tree units. The ingenuity of the proposed codec’s design, is that the information in intermediate frames are down-sampled and yet the frames can retain the original resolution. To enable random access to full resolution decoded frame in the decoded picture buffer as reference frame a downsampled version of the decoded full resolution frame is used. The test video sequences were coded using the proposed codec and standard MV-HEVC. Results show that the proposed codec gives a significantly higher coding performance over the MV- HEVC codec

MIXED-RESOLUTION HEVC BASED MULTIVIEW VIDEO CODEC

Studies have shown that mixed resolution based video codecs, also known as asymmetric spatial inter/intra view video codecs are successful in efficiently coding videos for low bitrate trans-mission. In this paper a HEVC based spatial resolution scaling type of mixed resolution coding model for frame interleaved multiview videos is presented. The proposed codec is designed such that the information in intermediate frames of the center and neighboring views are down-sampled, while the frames still retaining the original size. The codec’s reference frames structure is designed to efficiently encode frame interleaved multi-view videos using a HEVC based mixed resolution codec. The multi-view test video sequences were coded using the proposed codec and the standard MV-HEVC. Results show that the pro-posed codec gives significantly higher coding performance over the MV- HEVC codec at low bitrates

HEVC based Mixed-Resolution Stereo Video Codec

This paper presents a High Efficiency Video Codec (HEVC) based spatial mixed-resolution stereo video codec. The proposed codec applies a frame interleaving algorithm to reorder the stereo video frames into a monoscopic video. The challenge for mixed-resolution video coding is to enable the codec to encode frames with different frame resolutions. This issue is addressed by superimposing a low resolution replica of the decoded I-frame on its respective decoded picture, where remaining space of the frame is set to zero. This significantly reduces the computation cost for finding the best match. The proposed codec’s reference frames structure is designed to efficiently exploit both temporal and inter-view correlations. Performance of the proposed codec is assessed using five standard multiview video datasets and benchmarked against that of the anchor and the state-of-the-art techniques. Results show that the proposed codec yields significantly higher coding performance compared to the anchor and state-of-the-art techniques

HEVC Based Frame Interleaved Coding Technique for Stereo and Multi-View Videos

The standard HEVC codec and its extension for coding multiview videos, known as MV-HEVC, have proven to deliver improved visual quality compared to its predecessor, H.264/MPEG-4 AVC’s multiview extension, H.264-MVC, for the same frame resolution with up to 50% bitrate savings. MV-HEVC’s framework is similar to that of H.264-MVC, which uses a multi-layer coding approach. Hence, MV-HEVC would require all frames from other reference layers decoded prior to decoding a new layer. Thus, the multi-layer coding architecture would be a bottleneck when it comes to quicker frame streaming across different views. In this paper, an HEVC-based Frame Interleaved Stereo/Multiview Video Codec (HEVC-FISMVC) that uses a single layer encoding approach to encode stereo and multiview video sequences is presented. The frames of stereo or multiview video sequences are interleaved in such a way that encoding the resulting monoscopic video stream would maximize the exploitation of temporal, inter-view, and cross-view correlations and thus improving the overall coding efficiency. The coding performance of the proposed HEVC-FISMVC codec is assessed and compared with that of the standard MV-HEVC’s performance for three standard multi-view video sequences, namely: “Poznan_Street”, “Kendo” and “Newspaper1”. Experimental results show that the proposed codec provides more substantial coding gains than the anchor MV-HEVC for coding both stereo and multi-view video sequences

Multiview Video Coding for Virtual Reality

Virtual reality (VR) is one of the emerging technologies in recent years. It brings a sense of real world experience in simulated environments, hence, it is being used in many applications for example in live sporting events, music recordings and in many other interactive multimedia applications. VR makes use of multimedia content, and videos are a major part of it. VR videos are captured from multiple directions to cover the entire 360 field-of-view. It usually employs, multiple cameras of wide field-of-view such as fisheye lenses and the camera arrangement can also vary from linear to spherical set-ups. Videos in VR system are also subjected to constraints such as, variations in network bandwidth, heterogeneous mobile devices with limited decoding capacity, adaptivity for view switching in the display. The uncompressed videos from multiview cameras are redundant and impractical for storage and transmission. The existing video coding standards compresses the multiview videos effi ciently. However, VR systems place certain limitations on the video and camera arrangements, such as, it assumes rectilinear properties for video, translational motion model for prediction and the camera set-up to be linearly arranged. The aim of the thesis is to propose coding schemes which are compliant to the current video coding standards of H.264/AVC and its successor H.265/HEVC, the current state-of-the-art and multiview/scalable extensions. This thesis presents methods that compress the multiview videos which are captured from eight cameras that are arranged spherically, pointing radially outwards. The cameras produce circular fi sheye videos of 195 degree field-of-view. The final goal is to present methods, which optimize the bitrate in both storage and transmission of videos for the VR system. The presented methods can be categorized into two groups: optimizing storage bitrate and optimizing streaming bitrate of multiview videos. In the storage bitrate category, six methods were experimented. The presented methods competed against simulcast coding of individual views. The coding schemes were experimented with two data sets of 8 views each. The method of scalable coding with inter-layer prediction in all frames outperformed simulcast coding with approximately 7.9%. In the case of optimizing streaming birates, five methods were experimented. The method of scalable plus multiview skip-coding outperformed the simulcast method of coding by 36% on average. Future work will focus on pre-processing the fi sheye videos to rectilinear videos, in-order to fit them to the current translational model of the video coding standards. Moreover, the methods will be tested in comprehensive applications and system requirements

3D coding tools final report

Livrable D4.3 du projet ANR PERSEECe rapport a été réalisé dans le cadre du projet ANR PERSEE (n° ANR-09-BLAN-0170). Exactement il correspond au livrable D4.3 du projet. Son titre : 3D coding tools final repor

End-to-end 3D video communication over heterogeneous networks

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Three-dimensional technology, more commonly referred to as 3D technology, has revolutionised many fields including entertainment, medicine, and communications to name a few. In addition to 3D films, games, and sports channels, 3D perception has made tele-medicine a reality. By the year 2015, 30% of the all HD panels at home will be 3D enabled, predicted by consumer electronics manufacturers. Stereoscopic cameras, a comparatively mature technology compared to other 3D systems, are now being used by ordinary citizens to produce 3D content and share at a click of a button just like they do with the 2D counterparts via sites like YouTube. But technical challenges still exist, including with autostereoscopic multiview displays. 3D content requires many complex considerations--including how to represent it, and deciphering what is the best compression format--when considering transmission or storage, because of its increased amount of data. Any decision must be taken in the light of the available bandwidth or storage capacity, quality and user expectations. Free viewpoint navigation also remains partly unsolved. The most pressing issue getting in the way of widespread uptake of consumer 3D systems is the ability to deliver 3D content to heterogeneous consumer displays over the heterogeneous networks. Optimising 3D video communication solutions must consider the entire pipeline, starting with optimisation at the video source to the end display and transmission optimisation. Multi-view offers the most compelling solution for 3D videos with motion parallax and freedom from wearing headgear for 3D video perception. Optimising multi-view video for delivery and display could increase the demand for true 3D in the consumer market. This thesis focuses on an end-to-end quality optimisation in 3D video communication/transmission, offering solutions for optimisation at the compression, transmission, and decoder levels.Brunel University - Isambard Research Scholarshi