Re: Log does not work on matriz of uint8 - Help me please

[marco atzeri]

On 4/6/2012 7:59 AM, baldacim wrote:
> Hi everybody,
>
> I'm doing a work and I'm having some problems with log and uint8.
> I need apply a log on image (uint8 matriz) but the octave returns a error.
> Above the code, can someone help me please?
>
> im1 = imread(filein);
> uint8(im1);
> im2 = log2(im1);
>
> But it returns:
> error: octave_base_value::log2 (): wrong type argument `uint8 matrix'
>
> How can I apply log in a image??? Please give me some help.
> Thanks a lot.

wich version of octave ?
on 3.6.1


octave:7> a=rand(3,3)
a =

   0.299020   0.747812   0.606037
   0.392493   0.826722   0.125607
   0.049667   0.043875   0.404330

octave:8> b=uint8(a*1e2)
b =

  30  75  61
  39  83  13
   5   4  40

octave:9> log(b)
ans =

   3.4012   4.3175   4.1109
   3.6636   4.4188   2.5649
   1.6094   1.3863   3.6889