"\u010Cesk\u00E9 vysok\u00E9 u\u010Den\u00ED technick\u00E9 v Praze" . . "color to grayscale; grayscale; human perception"@en . . "Color images often have to be converted to grayscale for reproduction. Conversions which take into account local color changes are better at preserving details than global methods such as simply selecting the luminance channel. However, color changes across an image are expressed as color difference formulas with no direction, and the challenge is to find new formulas which can be used to determine an equivalent and consistent set of transitions between grays. We present two new local grayscale conversion techniques: one is based on the CIELab color difference formula, and the other on the Coloroid system and its experimental background. We obtain an inconsistent gradient field from a color image, find the closest consistent gradient field, and then integrate that to produce a grayscale image. The complexity of this method is linear in the number of pixels, making it suitable for high-resolution images; the results are pleasing and perceptually plausible." . "21230" . . . . "978-80-01-04016-4" . . "Color images often have to be converted to grayscale for reproduction. Conversions which take into account local color changes are better at preserving details than global methods such as simply selecting the luminance channel. However, color changes across an image are expressed as color difference formulas with no direction, and the challenge is to find new formulas which can be used to determine an equivalent and consistent set of transitions between grays. We present two new local grayscale conversion techniques: one is based on the CIELab color difference formula, and the other on the Coloroid system and its experimental background. We obtain an inconsistent gradient field from a color image, find the closest consistent gradient field, and then integrate that to produce a grayscale image. The complexity of this method is linear in the number of pixels, making it suitable for high-resolution images; the results are pleasing and perceptually plausible."@en . "\u010Cad\u00EDk, Martin" . "Perception Based Conversion of Color Images to Grayscale"@en . . "Perceptu\u00E1ln\u011B v\u011Brohodn\u00E1 konverze barevn\u00FDch obr\u00E1zk\u016F na \u0161edot\u00F3nov\u00E9"@cs . "386221" . "1"^^ . "[88D407065559]" . "Perceptu\u00E1ln\u011B v\u011Brohodn\u00E1 konverze barevn\u00FDch obr\u00E1zk\u016F na \u0161edot\u00F3nov\u00E9"@cs . "P(LC06008), Z(MSM6840770014)" . . . . . "1"^^ . "RIV/68407700:21230/08:03141353!RIV09-MSM-21230___" . "Perception Based Conversion of Color Images to Grayscale" . "Proceedings of Workshop 2008" . . . "1"^^ . . . "Praha" . "2008-02-18+01:00"^^ . "Perception Based Conversion of Color Images to Grayscale" . "Praha" . "Perception Based Conversion of Color Images to Grayscale"@en . . . "V praxi \u010Dasto pot\u0159ebujeme p\u0159ev\u00E9st barevn\u00FD obr\u00E1zek na \u010Dernob\u00EDl\u00FD (\u0161edot\u00F3nov\u00FD). Probl\u00E9mem je ztr\u00E1ta informace v d\u016Fsledku transformace barevn\u00FDch dat (3D) na \u0161edot\u00F3nov\u00E9 (1D). Nejjednodu\u0161\u0161\u00ED metody pro p\u0159evod pracuj\u00EDc\u00ED na principu odstran\u011Bn\u00ED barevn\u00E9 slo\u017Eky produkuj\u00ED velmi neuspokojiv\u00E9 obr\u00E1zky, v extr\u00E9mn\u00EDm p\u0159\u00EDpad\u011B a\u017E uniformn\u011B \u0161ed\u00FD v\u00FDsledek z p\u016Fvodn\u00EDho informa\u010Dn\u011B bohat\u00E9ho barevn\u00E9ho obr\u00E1zku. Pokro\u010Dil\u00E9 metody d\u00E1vaj\u00ED \u010Dasto nep\u0159edv\u00EDdateln\u00E9 v\u00FDsledky, zan\u00E1\u0161\u00ED do v\u00FDsledku artefakty, nebo jsou v\u00FDpo\u010Detn\u011B velmi n\u00E1ro\u010Dn\u00E9. Navr\u017Een\u00E1 metoda pro p\u0159evod barevn\u00E9ho obr\u00E1zku na \u0161edot\u00F3nov\u00FD pracuje v gradientn\u00ED oblasti. Navrhli jsme dv\u011B nov\u00E9 metody pro konstrukci gradientn\u00EDho pole a novou metodu pro korekci nekonzistence pole. Z konzistentn\u00EDho pole lze v\u00FDsledn\u00FD obr\u00E1zek z\u00EDskat pomoc\u00ED 2D integrace. Navr\u017Een\u00E1 metoda odstra\u0148uje nedostatky existuj\u00EDc\u00EDch metod, produkuje kvalitn\u00ED \u0161edot\u00F3nov\u00E9 obr\u00E1zky, m\u00E1 line\u00E1rn\u00ED opera\u010Dn\u00ED slo\u017Eitost a je tedy hodn\u00E1 i pro obr\u00E1zky s vysok\u00FDm rozli\u0161en\u00EDm."@cs . "RIV/68407700:21230/08:03141353" . .