Areas PapersEurographics 2011 - Areas Papershttps://diglib.eg.org:443/handle/10.2312/2902024-03-28T23:37:57Z2024-03-28T23:37:57ZHDR Photographic Pipeline for Camera Modules in Mobile DevicesMantiuk, R.Cybularczyk, J.Cichowicz, M.Smyk, M.Bazyluk, B.https://diglib.eg.org:443/handle/10.2312/EG2011.areas.077-0782022-03-28T12:17:24Z2011-01-01T00:00:00ZHDR Photographic Pipeline for Camera Modules in Mobile Devices
Mantiuk, R.; Cybularczyk, J.; Cichowicz, M.; Smyk, M.; Bazyluk, B.
A. Day and R. Mantiuk and E. Reinhard and R. Scopigno
We replace the standard image capture pipeline in mobile phones with an HDR acquisition pipeline based on the multi-exposure method. We report timings for basic HDR algorithms implemented in a smartphone with ARMv6 processor and discuss programming techniques that speed-up execution and reduce RAM memory usage. The results compare favourably to proprietary iPhone 4 HDR implementation and show that the HDR pipeline can be efficiently implemented on existing camera phones using high-level APIs and no dedicated hardware.
2011-01-01T00:00:00ZTowards Mobile HDR VideoCastro, T. K.Chapiro, A.Cicconet, M.Velho, L.https://diglib.eg.org:443/handle/10.2312/EG2011.areas.075-0762022-03-28T12:17:18Z2011-01-01T00:00:00ZTowards Mobile HDR Video
Castro, T. K.; Chapiro, A.; Cicconet, M.; Velho, L.
A. Day and R. Mantiuk and E. Reinhard and R. Scopigno
We present a novel method for High Dynamic Range video where the critical phases of the pipeline are based on histograms. It is possible to achieve high framerates, since the algorithm generates one HDR frame per captured frame. Also, the method is of low computational cost, making it particularly suited for devices with less powerful processors. An implementation of the capture process for the Nokia N900 smartphone, using the recent FCam API, is detailed.
2011-01-01T00:00:00ZPhotographically Guided Alignment for HDR ImagesAkyüzy, Ahmet Oguzhttps://diglib.eg.org:443/handle/10.2312/EG2011.areas.073-0742022-03-28T12:17:18Z2011-01-01T00:00:00ZPhotographically Guided Alignment for HDR Images
Akyüzy, Ahmet Oguz
A. Day and R. Mantiuk and E. Reinhard and R. Scopigno
This paper presents an automatic image alignment algorithm that alleviates the need to keep the camera still during the capture of a bracketed sequence to obtain an HDR image. Our algorithm assumes that the misalignment between the two consecutive exposures is translational. Using a photographically guided random search, our algorithm first finds properly exposed high contrast regions. The shift amount is then found by analyzing and matching the pixel correlations inside these regions.
2011-01-01T00:00:00ZAvoiding Chromaticity Creep with PseudoGreyGrimstead, I. J.Avis, N. J.https://diglib.eg.org:443/handle/10.2312/EG2011.areas.063-0702022-03-28T12:17:20Z2011-01-01T00:00:00ZAvoiding Chromaticity Creep with PseudoGrey
Grimstead, I. J.; Avis, N. J.
A. Day and R. Mantiuk and E. Reinhard and R. Scopigno
We examine the calibration of Commodity, Off-The-Shelf (COTS) monitors to the DICOM GreyScale Display Function (GSDF) standard (as used for medical imaging). We note that uncalibrated and calibrated (using commercial and non-commercial tools) monitors exhibit Chromaticity creep along the black body locus in CIE 1931 colourspace; this is at odds with high-end medical monitors which do not introduce colour-but cost significantly more than COTS colour monitors. Alternative algorithms are investigated to produce a DICOM GSDF compliant calibration, where we take into account both luminance and chromaticity. Using PseudoGrey we generate thousands of shades of grey on a colour monitor to produce a high dynamic range, albeit in greyscale, improving on the standard 256 shades of grey. In this work, we now restrict our introduction of colour to minimise chromaticity deviation from a given white point. We have found various chromatic anomalies with COTS monitors, and discuss our findings along with algorithmic variations to cope with such issues. We believe this work contributes to the availability of a robust method to calibrate COTS colour monitors to the GSDF and hence any required intensity curve whilst retaining a pure colour, enabling greyscale images with over 256 shades to be accurately displayed. This may have significant cost, and potentially improved diagnostic implications, in the reporting of medical radiological images, and could be used to display high dynamic range greyscale imagery (such as multiple exposure black and white photography).
2011-01-01T00:00:00Z