Mercurial > octave
changeset 20737:1a329319975b
im2double: allow floating point indexed images with any value.
* scripts/image/im2double.m: technically, an indexed image of a floating
point class must have positive real integers only. And it also shouldn't
be of class logical. However, Matlab does not enforce any of this so
we can't either. Also add tests.
| author | Carnë Draug <carandraug@octave.org> |
|---|---|
| date | Mon, 23 Nov 2015 16:07:23 +0000 |
| parents | 842765b159ed |
| children | f90295782d60 |
| files | scripts/image/im2double.m |
| diffstat | 1 files changed, 16 insertions(+), 7 deletions(-) [+] |
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--- a/scripts/image/im2double.m Mon Nov 23 15:25:54 2015 +0000 +++ b/scripts/image/im2double.m Mon Nov 23 16:07:23 2015 +0000 @@ -41,9 +41,10 @@ ## ## @end table ## -## If the second argument is the string @qcode{"indexed"}, then values are -## cast to double precision, and a +1 offset is applied if input is -## an integer class. +## If @var{img} is an indexed image, then the second argument should be +## the string @qcode{"indexed"}. If so, then @var{img} must either be +## of floating point class, or unsigned integer class and it will simply +## be cast to double. If it is an integer class, a +1 offset is applied. ## ## @seealso{double} ## @end deftypefn @@ -70,11 +71,14 @@ error ("im2double: second input argument must be the string \"indexed\""); elseif (any (isa (img, {"uint8", "uint16"}))) img = double (img) + 1; - elseif (isfloat (img) && isindex (img)) + elseif (isfloat (img) || isbool (img)) img = double (img); else + ## Technically, it could also be of logical class and we do not + ## enforce positive integers for floating for Matlab compatibility. + ## Still, no need to tell that to the user. error (["im2double: if IMG is indexed, then it must be positive " ... - "integer floating points or unsigned integer class"]); + "integer floating points, or unsigned integer class"]); endif else @@ -114,8 +118,13 @@ %! test_im2double_nd ("uint16", 0, 6535); %! test_im2double_nd ("int16", -32768, 32767); -%!error <positive integer floating> im2double (single ([0 1 2]), "indexed"); +## Test lack of input check for Matlab compatibility +%!assert (im2double ([0 1 2], "indexed"), [0 1 2]) +%!assert (im2double ([0 -1 -2], "indexed"), [0 -1 -2]) +%!assert (im2double ([0 -1.5 -2], "indexed"), [0 -1.5 -2]) +%!assert (im2double ([0 -1.5 -2i], "indexed"), [0 -1.5 -2i]) +%!assert (im2double ([false true], "indexed"), [0 1]) + %!error <unsigned integer class> im2double (int16 ([17 8]), "indexed"); %!error <unsigned integer class> im2double (int16 ([-7 8]), "indexed"); -%!error <unsigned integer class> im2double ([false true], "indexed"); %!error <must be the string "indexed"> im2double ([1 2 3], "non-indexed");