[magick-users] Converting 16-bit GRAY files to 8 bits

[Anthony Thyssen]

On Mon, 2 Feb 2009 15:01:46 -0500 (EST)
magick-users-bounces at imagemagick.org wrote:

| It seems that the statement
|      To force the use of an single 8bit greyscale channel use either
|        convert  input.jpg  -type Scale       gray.png
|        convert  input.jpg  -type GrayScale   gray.png
| at http://www.imagemagick.org/Usage/formats/#png_formats
| is incorrect.

Thinking about it you may be right.  JPG I think may have
had 8bit values.   Adding a   -depth 8 before the output
however will resolve that.

NOTE -depth is use for reading raw values (where depth can not be
determined by the file format), AND for writing to formats
that allow multiple bit depths.  Set it before the input or output
operation as appropriate.



  Anthony Thyssen ( System Programmer )    <A.Thyssen at griffith.edu.au>
 -----------------------------------------------------------------------------
          Treat your password like a toothbrush.
          Don't let anyone else use it and
          get a new one every six months.         ---  Cliff Stoll
 -----------------------------------------------------------------------------
     Anthony's Home is his Castle     http://www.cit.gu.edu.au/~anthony/