Re: Image[], Graphics[Raster[]]
- To: mathgroup at smc.vnet.net
- Subject: [mg100420] Re: Image[], Graphics[Raster[]]
- From: lehin.p at gmail.com
- Date: Wed, 3 Jun 2009 01:10:27 -0400 (EDT)
- References: <6147782.1243412890107.JavaMail.root@n11> <200905280829.EAA14200@smc.vnet.net>
On 2 =C9=C0=CE, 14:46, Jens-Peer Kuska <ku... at informatik.uni-leipzig.de> wrote: > Hi, > > what do you want ? a solution to the problem or > a pointer to the documentation ? > Hello, First of all I would want to get a pointer to documentation where such functions as "Image`ToGraphicsRaster" and "Image`PossibleImageQ" are documented. Are there other such built-in functions? At this moment I even can't imagine from where I could learn that such functions exists... And recently I had an opposite problem: how to convert Graphics[] (that contain Raster[]) to Image without loosing quality. Why I need this? There are two reasons: 1) Graphics has a default width 360 pixels and in this way the quality will be only 360 pixels width even if Raster[] inside Graphics[] contains much more points. And resizing does not help. It also directly affects Export[]... :( But Image[] always has true dimensions and preserves quality. I discussed it in detail here: http://tinyurl.com/njmpro 2) I have not found a perfect way how to change *default* width of Graphics[] (without using ImageSize). I discussed it here: http://tinyurl.com/l288ne I have created a function Raster2Image that converts Graphics[Raster []] to Image with preserving quality (as opposed to Image[Graphics]): Raster2Image = Image[Part[#, Sequence @@ Position[#, _Raster] [[1]], 1], ColorSpace -> "RGB"] &; But it is not so universal as I would want. May be there is an built- in alternative to this? Or you have more universal variant? I also created function fix4Graphics that fixes the above-mentioned behavior (loosing quality): fix4Graphics = Append[#, ImageSize -> Reverse[Take[Dimensions [Part[#, Sequence @@ Position[#, _Raster][[1]], 1]], 2]]] &; But it is also faraway from universality. So I am interested in more universal solutions and knowledge about undocumented functions for working with graphics...