DC coefficient recovery for JPEG images in ubiquitous communication systems

2019 ◽  
Vol 96 ◽  
pp. 23-31 ◽  
Author(s):  
Han Qiu ◽  
Gerard Memmi ◽  
Xuan Chen ◽  
Jian Xiong
Keyword(s):  
Communication Systems ◽  
Jpeg Images ◽  
Dc Coefficient ◽  
Coefficient Recovery

scholarly journals Content and Privacy Protection in JPEG Images by Reversible Visual Transformation

2020 ◽  
Vol 10 (19) ◽  
pp. 6776
Author(s):  
Xin Cao ◽  
Yuxuan Huang ◽  
Hao-Tian Wu ◽  
Yiu-ming Cheung
Keyword(s):  
Cloud Computing ◽  
Privacy Protection ◽  
Location Information ◽  
File Format ◽  
Original Image ◽  
Secret Key ◽  
File Size ◽  
Jpeg Images ◽  
Encryption Schemes ◽  
Dc Coefficient

With the popularity of cloud computing and social networks, more and more JPEG images are stored and distributed. Consequently, how to protect privacy and content in JPEG images has become an important issue. Although traditional encryption schemes can be employed, the file format of JPEG images is changed so that their usage may be affected. In this paper, a reversible visual transformation algorithm is proposed to protect content in JPEG images. Specifically, the DC coefficient in each user-selected block is modified, while the information required to recover it is reversibly hidden into AC coefficients. Then the signs of AC coefficients in the selected blocks are flipped and the blocks are further scrambled with a secret key. By embedding the location information of the selected blocks in a transformed image, the original image can be exactly recovered when needed. Besides, regions to be protected can be arbitrarily chosen without substantially affecting the rest of the image. The experimental results on a set of JPEG images validate the efficacy and reversibility of the proposed algorithm. In addition, good performance is achieved in terms of invisibility of the protected content, image quality, file size preservation and security.

Transmission Error Analysis and DC Coefficient Recovery for Compressed Image

2015 ◽  
Vol 33 (4) ◽  
pp. 405-414
Author(s):  
Jigisha N. Patel ◽  
Pratibha Varma ◽  
Suprava Patnaik
Keyword(s):  
Error Analysis ◽  
Transmission Error ◽  
Dc Coefficient ◽  
Coefficient Recovery

Plant peptide hormone signalling

2015 ◽  
Vol 58 ◽  
pp. 115-131 ◽  
Author(s):  
Ayane Motomitsu ◽  
Shinichiro Sawa ◽  
Takashi Ishida
Keyword(s):  
Communication Systems ◽  
Cell Communication ◽  
Peptide Hormone ◽  
Peptide Hormones ◽  
Target Cells ◽  
Signalling Molecules ◽  
Receptor Complexes ◽  
Environmental Responses ◽  
Plant Life Cycle ◽  
Multicellular Organisms

The ligand–receptor-based cell-to-cell communication system is one of the most important molecular bases for the establishment of complex multicellular organisms. Plants have evolved highly complex intercellular communication systems. Historical studies have identified several molecules, designated phytohormones, that function in these processes. Recent advances in molecular biological analyses have identified phytohormone receptors and signalling mediators, and have led to the discovery of numerous peptide-based signalling molecules. Subsequent analyses have revealed the involvement in and contribution of these peptides to multiple aspects of the plant life cycle, including development and environmental responses, similar to the functions of canonical phytohormones. On the basis of this knowledge, the view that these peptide hormones are pivotal regulators in plants is becoming increasingly accepted. Peptide hormones are transcribed from the genome and translated into peptides. However, these peptides generally undergo further post-translational modifications to enable them to exert their function. Peptide hormones are expressed in and secreted from specific cells or tissues. Apoplastic peptides are perceived by specialized receptors that are located at the surface of target cells. Peptide hormone–receptor complexes activate intracellular signalling through downstream molecules, including kinases and transcription factors, which then trigger cellular events. In this chapter we provide a comprehensive summary of the biological functions of peptide hormones, focusing on how they mature and the ways in which they modulate plant functions.

Instruction Using Augmentative and Alternative Communication Supports: Description of Current Practices by Speech-Language Pathologists Who Work With Children With Autism Spectrum Disorder

2020 ◽  
Vol 29 (2) ◽  
pp. 586-596 ◽  
Author(s):  
Kaitlyn A. Clarke ◽  
Diane L. Williams
Keyword(s):  
Autism Spectrum Disorder ◽  
Augmentative And Alternative Communication ◽  
Communication Systems ◽  
Diagnostic Category ◽  
Children With Autism ◽  
Autism Spectrum ◽  
Spectrum Disorder ◽  
Alternative Communication ◽  
Speech Language Pathologists ◽  
Processing Differences

Purpose The aim of this research study was to examine common practices of speech-language pathologists (SLPs) who work with children with autism spectrum disorder (ASD) with respect to whether or not SLPs consider processing differences in ASD or the effects of input during their instruction. Method Following a qualitative research method, how SLPs instruct and present augmentative and alternative communication systems to individuals with ASD, their rationale for method selection, and their perception of the efficacy of selected interventions were probed. Semistructured interviews were conducted as part of an in-depth case report with content analysis. Results Based on completed interviews, 4 primary themes were identified: (a) instructional method , (b) input provided , (c) decision-making process , and (d) perceived efficacy of treatment . Additionally, one secondary theme, training and education received , was identified . Conclusions Clinicians reported making decisions based on the needs of the child; however, they also reported making decisions based on the diagnostic category that characterized the child (i.e., ASD). The use of modeling when teaching augmentative and alternative communication to individuals with ASD emerged as a theme, but variations in the method of modeling were noted. SLPs did not report regularly considering processing differences in ASD, nor did they consider the effects of input during instruction.

Thoughts on Grammar Intervention in AAC

2008 ◽  
Vol 17 (2) ◽  
pp. 43-49 ◽  
Author(s):  
Marc Fey
Keyword(s):  
Language Impairment ◽  
Specific Language Impairment ◽  
Augmentative And Alternative Communication ◽  
Communication Systems ◽  
Target Language ◽  
Alternative Communication ◽  
Physical Limitations ◽  
Communication Needs ◽  
Communication Interventions ◽  
Planning Intervention

Abstract In this article, I propose that, for several reasons, grammar should be an early focus of communication interventions for young children using augmentative and alternative communication (AAC) systems. The basic goals for such programs should be to facilitate the child's comprehension of the language of the community, or the target language, thus leading the way to literacy, and to foster the child's use of symbol combinations that mirror the grammatical patterns of speaking children acquiring the target language, even if they cannot be fully grammatically complete. I introduce five principles that underlie most successful approaches to grammar interventions with children with specific language impairment. My initial attempts to apply these principles to interventions with children with complex communication needs indicate that they may be of considerable value to clinicians planning intervention programs. On the other hand, the challenges posed by the intellectual and physical limitations of many AAC users and their communication systems make it necessary to modify at least Principle 5 if the basic goals of intervention are to be met.

Helping the General Education Team Support Students Who Use AAC

2012 ◽  
Vol 21 (3) ◽  
pp. 82-91 ◽  
Author(s):  
Carole Zangari
Keyword(s):  
Academic Achievement ◽  
General Education ◽  
Communication Skills ◽  
Communication Systems ◽  
General Education Teachers ◽  
Practice Opportunities ◽  
Support Students ◽  
Successful Students

Abstract To be successful, students who use AAC and attend general education classes require extensive supports and frequent practice with their communication systems. In this article, I explore the challenges faced by educational teams and discuss strategies for helping general education teachers, paraprofessionals, and others provide the AAC learning and practice opportunities these students need to maximize their communication skills and academic achievement.

Sign in / Sign up

Export Citation Format

Share Document