An image acquisition system, which consists of four
basic components: illumination, camera, hardware,
and software (Fig. 2). Images were captured using an
image acquisition system for color digital camera
similar to that developed by Papadakis et al.[12] The
sample was illuminated using four fluorescent lamps
(length of 60 cm) with a surface temperature of 65
C
(ParsShahab Company, Tehran, Iran) and a color
reproduction index close to 95%. The four lamps were
arranged as a square, 35 cm above the sample and at
an angle of 45 with the sample plane, to give a uniform
light intensity over the sample. Images of pumpkin
samples were captured directly by the use of a
CCD digital camera (Sony, Cybershot, DSC40,
Tokyo, Japan) with black painted tiles as background.
The digital camera was located vertically at a distance
of 12 cm from the sample. The angle between the camera
lens axis and the light sources was set around 45 to
capture the diffuse reflection responsible for the color,
which occurred at that angle from the incident light The shutter speed was 1=8 s with the use of no zoom
and flash. Both the sample illuminators and the
CCD were placed inside a wooden box whose internal
walls were covered with black clothes to avoid the light
and reflection from the room. Images were captured at
the resolution of 1728 2304 pixels. The acquired
images were sent to a Pentium IV, 2.2-GHz computer.
Sony Remote Capture Software (version 2.7.0) was
used for acquiring the images directly to the computer
in a JPEG format.