Image quality optimization, via application of contextual contrast sensitivity and discrimination functions

What is the best luminance contrast weighting-function for image quality optimization? Traditionally measured contrast sensitivity functions (CSFs), have been often used as weighting-functions in image quality and difference metrics. Such weightings have been shown to result in increased sharpness and perceived quality of test images. We suggest contextual CSFs (cCSFs) and contextual discrimination functions (cVPFs) should provide bases for further improvement, since these are directly measured from pictorial scenes, modeling threshold and suprathreshold sensitivities within the context of complex masking information. Image quality assessment is understood to require detection and discrimination of masked signals, making contextual sensitivity and discrimination functions directly relevant. In this investigation, test images are weighted with a traditional CSF, cCSF, cVPF and a constant function. Controlled mutations of these functions are also applied as weighting-functions, seeking the optimal spatial frequency band weighting for quality optimization. Image quality, sharpness and naturalness are then assessed in two-alternative forced-choice psychophysical tests. We show that maximal quality for our test images, results from cCSFs and cVPFs, mutated to boost contrast in the higher visible frequencies.

Media ‘Globalization’ as Survival Strategy for Authoritarian Regimes In the Arab Middle East

Sakr challenges the notion that transnational media technologies have forced states in the Arab Middle East to cede ever more control to non-state players since the 1990s. Taking account of a long history of foreign political engineering in Arab countries, she probes the realities of Arab broadcasting privatization, intra-regional harmonization of government communication policies, and external financial support for media freedom and reform, to show how Arab governments were large successfully in harnessing forces implicated in media globalization in a way that entrenched authoritarian elements of the status quo. The findings validate an alternative to globalization theory that places a dual focus on the agency of national ruling elites and the international structures that underpin the power of those elites today, as in the past.

The Big Society and the conjunction of crises: Justifying welfare reform and undermining social housing

This article considers the idea of the ‘Big Society’ as part of a long-standing debate about the regulation of housing. Situating the concept within governance theory, the article considers how the idea of the Big Society was used by the UK coalition government to justify a radical restructuring of welfare provision. The fundamental rationale for this transformation was that the UK was forced to respond to a conjunction of crises in morality, the state, ideology and economics. Representing a fundamental departure from earlier attempts at welfare reform, the government has undertaken a reform programme which has had a severe effect on the social housing sector. The article argues that the result has been a combination of libertarianism and authoritarianism, alongside an intentionally more destructive combination of stigmatization and fatalism. The consequence is to undermine the principle of social housing which will not only prove detrimental for residents but raises significant dilemmas for those working in the housing sector.

Survival or Sustainability? Contributions of Innovatively-Managed News Ventures to the Future of Egyptian Journalism

In the repressive political climate prevailing in Egypt in 2013-15, news ventures aspiring to high standards of reporting were forced to innovate. This paper analyses three Egyptian start-ups that experimented with novel revenue streams and news services during that period, to gain insights into their approaches to managing journalism. In the process it compares different criteria for assessing sustainability and concludes that, in adverse political environments, narrow economic measures of profitability and survival may give a misleading picture as to the sustainability of the kind of journalism conducive to democratic practice. Operating collaboratively, transparently and ethically may slow productivity and profitability in the short term while laying stronger foundations for durable relations among media teams, as well as with readers and advertisers, in the long run.