Specify the units – I seem to remember having a problem when I omitted this option (although DPI should be the default), for example: convert. convert -units PixelsPerInch -size x xc:black -resample 96 The GIF format actually totally ignores/discards the dpi anyway, as you can see diff finds. #resample. As for your screen — measure it! it is typically (these days) 90 to dpi. Remember dpi.
|Published (Last):||14 September 2007|
|PDF File Size:||8.31 Mb|
|ePub File Size:||8.46 Mb|
|Price:||Free* [*Free Regsitration Required]|
ImageMagick source code and algorithms are discussed here.
Usage questions which are too arcane for the normal user list should also be posted here. I think you meant “-density”.
But a different order is recommended with current IM versions so that congert works for all images: Select all convert -units PixelsPerInch image -density resultimage. Select all convert -units PixelsPerInch image -resample resultimage.
Under what conditions do you need to have -units first other than for vector images? This is new to me. Is it a bug?
conversion – Convert image with imagemagick command line convert tool – Unix & Linux Stack Exchange
Select all convert rose: Select all convert -units PixelsPerInch rose1. Select all convert rose1. I would probably have expected something similar with units, in which case order between the two should not matter.
However they both probably should be set after reading the image. The problem is that density is also a ‘input setting’. That is a global setting that is saved so that vector images can use the value when they are ‘rasterized’.
convert image 75 dpi to dpi – ImageMagick
As such their use is confusing. That is -density is being dual purposed as both a input setting for images that is created and read in, and as image meta-data modifier operator after images have been read in.
Covnert other words it is more than likely that the two aspects are causing buggy behaviour. It is for this reason that many options such as -label is strictly a input setting only, while -set label is strictly used as a meta-data attribute changing operator!
Attributes, Properties and Artifacts http: