The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In mobile video applications, where unreliable networks are commonplace, corrupted video packets can have a profound impact on the quality of the user experience. In this paper, we show that, in a wide range of operating conditions, selectively reusing data resulting from decodable errorneous packets leads to better results than frame copy. This selection is guided by a novel concept that combines...
In this paper, we focus on the problem of improving image compression through steganography. Even if the purposes of digital steganography and data compression are by definition contradictory, these techniques might be used jointly to compress and to hide information within the same digital support. A novel image compression scheme, employing steganography to decrease the data file size, is investigated...
During wireless video transmission, when an error is detected at the receiver, the packet is dropped immediately and error concealment is performed. However, this procedure does not always provide satisfactory results, especially when the motion is complicated or scene change occurs. Moreover, there are often uncorrupted macroblocks in the distorted packet. Hence, it can be important to utilize the...
The L∞-constrained image coding is a technique to achieve substantially lower bit rate than strictly (mathematically) lossless image coding while still imposing a tight error bound at each pixel (colloquially referred to as near-lossless image coding). However, this technique becomes inferior in the L2 distortion metric if the bit rate decreases further. We propose a new soft decoding approach to...
In this paper, we present a new depth map coding scheme to improve coding efficiency. For this purpose, we developed an adaptive bilateral filter that restores the coded depth maps in accordance with the estimated noise variance. More specifically, each pixel is classified in such a way that the distortion cost is minimized and is restored depending on local noise level. The restored picture is used...
Adaptation for scalable video is one of the recent challenges in video distribution over modern networks, which are heterogeneous both in terms of available bandwidth and user end terminal capability. Scalable Video Coding offers the possibility to adapt the content following the “quality layer” abstraction. In this work we present a new method to optimally define quality layers using Integer Linear...
Image data compressed with JPEG XR when transmitted over error-prone channels is severely distorted. In fact, due to the adaptive coding strategies used by the codec, even a single bit error causes a mismatch in the alignment of the reading position from the bitstream, leading to completely different images at the decoder side. We propose an extension to the JPEG XR algorithm, consisting in an error...
The paper presents a novel error robustness method for H.264/AVC video data, based on the redundant data encoding concept. The proposed redundant data codec incorporates the Wyner-Ziv (WZ) theory and motion vectors (MV) of the H.264/AVC scheme. The performance of the proposed method is evaluated under both error free and error prone Internet Protocol (IP) Packet network environments. The proposed...
The error concealment is an important technique in the video transmission that can assure the reconstruction video quality and can efficiently recovery the data loss and the data errors in the transmission process caused by the transmission environment, thus improve the subjective quality of the video received in the end. In order to enhance the error resilience of AVS-P2 standard, in this paper,...
Compressed video streams are sensitive to errors and losses when transmitted over wireless error-prone channels. In this paper, we propose an Error Resilient (ER) scheme based on Reversible Data Hiding (RDH) and Redundant Slice (RDH-RS). Reversible data hiding is quite effective in unequal protection and can provide satisfactory protection to vital information, while redundant slice works well in...
Fractal image compression has been interested due to highly possible compression ratio and selectable quality variation. However, one of disadvantages in fractal image compression is that it takes long time for encoding. So far, there are several methods proposed to get the high speed of encoding such as Fisher's, Hurtgen's and Saupe's, etc. In this paper, implementation of fractal image compression...
The contribution of this paper to compressive sampling (CS) based image coding is two-fold. Firstly, we propose more accurate CS performance metrics: 1. Adopt bit-rate to replace common but inaccurate measurement rate in R-D performance. 2. Algorithm complexity is measured by the elapsed execution time and their ratios. Secondly, we improve the R-D performance by exploiting wavelet domain signal characteristics...
In this paper we analyze current H.264 rate distortion algorithms (RD), specifically those developed in the x264 codec which is an open source and high performance H.264/AVC encoder, and evaluate their suitability for high definition video conferencing (HDVC). Moreover, we report the current shortcomings of these methods and highlight issues to be addressed for future research, as well as the requirements...
In this paper, Advanced Adaptive Image Coding (AAIC) is proposed to increase compression performance for frame delay memory applications. The AAIC contains two techniques to improve the quality of decompressed images. The first is a Mean Adaptive Image Coding (MAIC) to reduce the impact of noise on image compression. The second is a Content-based Bit Exchange Technique (CBBET) to provide an adaptive...
In this paper a secret message/image transmission technique has been proposed through (2, 2) visual cryptographic shares which are covered by meaningful images so that a potential eavesdropper won't know there's a message to be read. A binary image is taken as cover image and authenticating message/image has been fabricated into it through a hash function where two bits in each pixel within four bits...
Under many viewing circumstances, asymmetric stereoscopic video coding provides similar perceived quality with significant decrease in bitrate, computational complexity, and memory usage compared to conventional stereoscopic video coding. However, in other circumstances, users may prefer conventional symmetric stereoscopic video to asymmetric stereoscopic video. This paper presents a stereoscopic...
In this paper, a quantization scheme based on hard-decision partition and adaptive reconstruction levels is proposed for High Efficiency Video Coding (HEVC), the video coding standard currently under development, which has demonstrated approximately 40% bit saving compared to H.264/AVC. For each video frame, the residual signal after motion estimation is transformed and then quantized by a hard-decision...
The objective of this study is to develop the transmitting environment simulation of uncompressed high-definition (HD) video system over Additive White Gaussian Noise (AWGN) channel. This system analyzes and compares the Peak Signal-to-Noise Ratio (PSNR) performance over 16-QAM and QPSK modulation. Equal Error Protection (EEP) and Unequal Error Protection (UEP) methods for video streaming are also...
To fairly allocate network bandwidth for different streams and to achieve a smooth quality between different video sequences are two key issues in multi-stream applications. In this paper, a new joint rate control scheme for multiple video streams based on game theory is proposed. We achieve a fair rate allocation in video quality between different sequences by Nash Bargaining theory under the constraints...
Video error concealment is a post-processing technique that conceals the errors in a decoded video sequence based on data available only at the decoder. Most of the current techniques adopt the approach that recovers the Motion Vector (MV) of a lost image block, uses that MV to look for data to fill in the blank then performs some refinements. We propose a method that does not rely on MV recovery,...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.