From: nicolas Date: Fri, 22 Oct 2010 16:34:52 +0000 (+0000) Subject: (no commit message) X-Git-Tag: 7.0.1-0~8650 X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=3061b8a471c700e17dfa94895853a8fc2a261a49;p=imagemagick --- diff --git a/magick/resize.c b/magick/resize.c index e90a21574..a8cee499a 100644 --- a/magick/resize.c +++ b/magick/resize.c @@ -549,64 +549,72 @@ static MagickRealType Welsh(const MagickRealType x, % crossing is (36 sqrt 2 + 123)/(72 sqrt 2 + 47) which is almost % identical to the first crossing of the other two. % -% 'EXPERT' OPTIONS +% 'EXPERT' OPTIONS: % -% You can override any and all filter settings. This is not advised -% unless you have expert knowledge of the use of resampling filtered -% techniques. Check on the results of your selections using the -% "filter:verbose" setting to make sure you get the exact filter you -% want. +% (Not recommended without expert knowledge of resampling and +% filtering.) +% +% You can override any and all filter settings. Use "filter:verbose" +% to make sure that the overall effect of your selections is as +% expected. +% +% "filter:verbose" Output the exact results of the filter +% selections made, as well as plotting data for graphing the +% resulting filter over support range (blur adjusted). % % "filter:filter" Select the main function associated with % this filter name, as the weighting function of the filter. % This can be used to set a windowing function as a weighting % function, for special purposes, such as graphing. % -% If a "filter:window" operation has not been provided, then a 'Box' -% windowing function will be set to denote that no windowing function -% is being used. -% -% "filter:window" Select this windowing function for the filter. -% While any filter could be used as a windowing function, using the -% 'first lobe' of that filter over the whole support window, using a -% non-windowing function is not advisible. If no weighting filter -% function is specifed a 'SincFast' filter will be used. -% -% "filter:lobes" Number of lobes to use for the Sinc/Jinc filter. -% This a simpler method of setting filter support size that will -% correctly handle the Sinc/Jinc switch for an operators filtering -% requirements. Only integers should be given. -% -% "filter:support" Set the support size for filtering to the size given -% This not recommended for Sinc/Jinc windowed filters (lobes should -% be used instead). This will override any 'filter:lobes' option. -% -% "filter:win-support" Scale windowing function to this size instead. -% This causes the windowing (or self-windowing Lagrange filter) to act -% is if the support window it much much larger than what is actually -% supplied to the calling operator. The filter however is still -% clipped to the real support size given, by the support range suppiled -% to the caller. If unset this will equal the normal filter support +% If a "filter:window" operation has not been provided, then a +% 'Box' windowing function will be set to denote that no +% windowing function is being used. +% +% "filter:window" Select this windowing function for the filter. +% While any filter could be used as a windowing function, using +% the 'first lobe' of that filter over the whole support +% window, using a non-windowing function is not advisible. If +% no weighting filter function is specifed a 'SincFast' filter +% will be used. +% +% "filter:lobes" Number of lobes to use for the Sinc/Jinc filter. +% This a simpler method of setting filter support size that +% will correctly handle the Sinc/Jinc switch for an operators +% filtering requirements. Only integers should be given. +% +% "filter:support" Set the support size for filtering to the size +% given This not recommended for Sinc/Jinc windowed filters +% (lobes should be used instead). This will override any +% 'filter:lobes' option. +% +% "filter:win-support" Scale windowing function to this size +% instead. This causes the windowing (or self-windowing +% Lagrange filter) to act is if the support window it much much +% larger than what is actually supplied to the calling +% operator. The filter however is still clipped to the real +% support size given, by the support range suppiled to the +% caller. If unset this will equal the normal filter support % size. % -% "filter:blur" Scale the filter and support window by this amount. +% "filter:blur" Scale the filter and support window by this amount. % A value >1 will generally result in a more burred image with % more ringing effects, while a value <1 will sharpen the % resulting image with more aliasing and Morie effects. % -% "filter:sigma" The sigma value to use for the Gaussian filter only. -% Defaults to '1/2' for orthogonal and 'sqrt(2)/2' for cylindrical -% usage. It effectially provides a alturnative to 'blur' for Gaussians -% without it also effecting the final 'practical support' size. +% "filter:sigma" The sigma value to use for the Gaussian filter +% only. Defaults to '1/2' for orthogonal and 'sqrt(2)/2' for +% cylindrical usage. It effectially provides a alturnative to +% 'blur' for Gaussians without it also effecting the final +% 'practical support' size. % % "filter:b" -% "filter:c" Override the preset B,C values for a Cubic type of filter -% If only one of these are given it is assumes to be a 'Keys' -% type of filter such that B+2C=1, where Keys 'alpha' value = C +% "filter:c" Override the preset B,C values for a Cubic type of +% filter If only one of these are given it is assumes to be a +% 'Keys' type of filter such that B+2C=1, where Keys 'alpha' +% value = C % -% "filter:verbose" Output the exact results of the filter selections -% made, as well as plotting data for graphing the resulting filter -% over support range (blur adjusted). +% Examples: % % Set a true un-windowed Sinc filter with 10 lobes (very slow) % -define filter:filter=Sinc