Pyramid Vector Quantization of Video Subband With Dithering

2012 ◽  
Author(s):  
Mohsen Ashourian ◽  
Zulkalnain Mohd. Yusof ◽  
Sheikh Hussain S. Salleh ◽  
Syed Abd. Rahman S. A. Bakar
Keyword(s):  
Video Compression ◽  
Vector Quantization ◽  
Three Dimensional ◽  
Low Complexity ◽  
Video Codec ◽  
Subjective Test ◽  
Compression Scheme ◽  
Fixed Rate ◽  
Video Signals ◽  
Video Frames

This paper describes the development of a low complexity and fixed–rate video compression scheme based on three–dimensional subband coding of video signals. The video codec first performs three–dimensional subband decomposition on a group of video frames, and then encode high frequency subbands with pyramid vector quantization and lowest tempo–spatial band with a DPCM coding in time and space. To improve the visual quality of reconstructed video, different types of subtractive and non–subtractive dithering of pyramid vector quantizers were experimented and its effectiveness was proved by a standard pair comparison subjective test. Coder complexity was reduced by using longer filters in the first level of spatial decomposition for better selectivity and coding gain and shorter filter in the second level of decomposition for lower complexity. Results at different low bit–rate (64, 128 and 384 Kbps) for several standard video sequences are reported and compared with ITU standard H.263.

Using Multiscale Edge Detection for Low Bit-Rate Subband Video Coding

2012 ◽  
Author(s):  
Mohsen Ashourian ◽  
Zulkalnain Mohd. Yusof ◽  
Sheikh Hussain S. Salleh ◽  
Syed Abd. Rahman S. A. Bakar
Keyword(s):  
Video Coding ◽  
Video Compression ◽  
Three Dimensional ◽  
Spatial Filter ◽  
Video Codec ◽  
Bit Rate ◽  
Low Bit Rate ◽  
Video Frames ◽  
Tele Monitoring ◽  
Efficient Selection

This paper introduces a video compression system for very low bit–rate video–conferencing and tele–monitoring applications. The video codec first performs a three–dimensional subband decomposition on a group of video frames, and then encode the subbands with different quantization methods. By using a cubic spline wavelet, the spatial filter bank acts as a multiscale edge detector. This property is used for efficient selection and coding of high frequency subbands with geometric vector quantization. For lowest tempo–spatial subband, a DPCM coding with an entropy coder was used. Results at several low bit rates (16,32, 64, 128 Kbps) are reported and compared with H.263, the standard for low bit rate video coding.

scholarly journals Analisis Perbandingan Teknik Video Codec H.264/AVC, H.265/HEVC, VP9 dan AV1

2021 ◽  
Vol 5 (2) ◽  
pp. 187-195
Author(s):  
Ayu Shafira Tubagus ◽  
◽  
Rizal Saepul Mahdi ◽  
Adhi Rizal ◽  
Aries Suharso ◽  
...  
Keyword(s):  
Video Compression ◽  
Compression Ratio ◽  
Signal To Noise Ratio ◽  
Video Codec ◽  
The Other ◽  
Compressed Video ◽  
File Size ◽  
Video Frames ◽  
Quality Video ◽  
Short Time

Video applications consume more energy on the Internet and can be accessed by electronic devices, due to an increase in the consumption of high-resolution and high-quality video content, presenting serious issues to delivery infrastructure that needs higher video compression technologies. The focus of this paper is to evaluate the quality of the most current codec, AV1, to its predecessor codec. The comparison was made experimentally at two video resolutions (1080p and 720p) by sampling video frames with various CRF/CQP values and testing several parameters analyses such as encoding duration, compression ratio, bit rate, Mean Square Error (MSE), and Peak Signal to Noise Ratio (PSNR). The AV1 codec is very great in terms of quality and file size, even though it is slower in terms of compression speed. The H.265/HEVC codec, on the other side, beats the other codec in terms of compression ratio. In conclusion, the H.265/HEVC codec is suggested as a material for obtaining a well compressed video with small file size and a short time.

scholarly journals A Low-Complexity Region-Based Authentication Algorithm for 3D Polygonal Models

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Yuan-Yu Tsai ◽  
Tsung-Chieh Cheng ◽  
Yao-Hsien Huang
Keyword(s):  
Three Dimensional ◽  
Low Complexity ◽  
Secret Key ◽  
Authentication Code ◽  
Geometrical Properties ◽  
Property Evaluation ◽  
Adaptive Embedding ◽  
Local Properties ◽  
Embedding Rate ◽  
Polygonal Models

This study proposes a low-complexity region-based authentication algorithm for three-dimensional (3D) polygonal models, based on local geometrical property evaluation. A vertex traversal scheme with a secret key is adopted to classify each vertex into one of two categories: embeddable vertices and reference vertices. An embeddable vertex is one with an authentication code embedded. The algorithm then uses reference vertices to calculate local geometrical properties for the corresponding embeddable vertices. For each embeddable vertex, we feed the number of reference vertices and local properties into a hash function to generate the authentication code. The embeddable vertex is then embedded with the authentication code, which is based on a simple message-digit substitution scheme. The proposed algorithm is of low complexity and distortion-controllable and possesses a higher and more adaptive embedding capacity and a higher embedding rate than most existing region-based authentication algorithms for 3D polygonal models. The experimental results demonstrate the feasibility of the proposed algorithm.

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