program noisepic

  use spitpgm
  implicit none

  integer                   :: numframe = 0

  integer                   :: nbarg
  character(len=256)        :: arg


  nbarg = IARGC()
  if (nbarg .GT. 0) then
       call GETARG(1, arg)
       ! write (0, '(A40, A5)') "argument = ",  arg
       read (arg, *) numframe
  endif

  call make_noise_pic(numframe)

contains
!-- ------------------------------------------------------------------
subroutine make_noise_pic (value)

  integer, intent(in)        :: value

  integer                               :: foo
  integer, dimension(:,:), allocatable  ::  pic
  character (len=280)                   ::    filename

  allocate(pic(320, 240))

  pic = 0

  call srand(value+34)
  foo = irand()
  print *, 'val=', value, '       rnd=', foo

  call plot_noise_pic(pic, 15000)

  write (filename, "(a, i5.5, a)") "", value, ".pgm"
  call spit_as_pgm_8(pic, trim(filename))

end subroutine
!-- ------------------------------------------------------------------
subroutine plot_noise_pic(picz, nbre)

  integer, dimension(:,:), intent(inout) :: picz
  integer, intent(in)                    :: nbre

  integer                                :: width, height
  integer                                :: quux, ix, iy, iv


  width = ubound(picz, 1)  ;  height = ubound(picz, 2)
  ! print *, 'sz picz', width, height

  do quux=1, nbre

    ix = 1 + mod ( irand(), width )
    iy = 1 + mod ( irand(), height )
    iv = mod ( irand(), 256 )

    ! print *, ix, iy
    picz(ix, iy) = iv

  enddo

end subroutine

!-- ------------------------------------------------------------------

end program