Reading Images using Spring (old module Impima)
Loading Spring
The Windows version do not allow access to images from
magnetic tapes. Other files recorded in CDs or other media
are accessible.
Check below the steps you need to follow.
Running "Spring":
- after downloading and installing SPRING, you can
access "Spring" module through the file "spring.exe"
or using shortcut created on your desktop;
- click on Start - Programs - Spring
and choose Spring.
Operating the SPRINGmodule
Loading
an Image:
- open the Spring module as described
above;
- click on File - Open Image on
the main menu
. The window "Image Viewer" (Open)
is shown (check more details on
how to operate it);
- select in "Examinar" (Choose) the
drive where the image you want to read is located;
- select in "Arquivos do Tipo:" (Directory)
the image format:
- TIFF e GEOTIFF (*.tif) files;
- Volume Directory (vold*.dat) for Landsat
or SPOT images, BSQ and BIL formats respectively;
- Fast Format files (HEADER.dat);
- GRIB files (*.grb) for images already
read by "Impima" and saved in this format;
- SPG files (*.spg)
- SITIM (*.d) files (Sitim-INPE format);
- RAW files (*.*) for raw images;
- select the image file that corresponds to the
format chosen and click on "Abrir" (Open);
- observe that the Input Image Parameters
come along and are presented;
- choose on the Bands list one of the
images (if there is more than one);
- click on Apply - Draw on the
main menu or
. In case the image is in TIFF
format, you will need to inform the Pixel Size
in meters. For images in RAW format, you will need to
inform the number of Col x Lin (Columns x Lines)
and Pixel Size in meters. The image is presented
on the drawing area.
NOTES:
- Only one band (monochromatic image) can be visualized
on "Spring", even if there are more than one band on the
image file.
- For TM/Landsat-5 GEOTIFF images, it is possible to
supply, as an input parameter, the WRS (World Reference
System), since this information is not defined for this
format.
The system always shows the whole image on "Spring"
display. Therefore, most of the times, the image is
resampled. For practical reasons, the system automatically
calculates the resampling factor when the image is greater
than 1500 lines x 1500 columns.
If you want to select (cut) a smaller region of the
image, you should first present the whole image on the
screen.
To
select and record a smaller area:
- Load the image as described above. Observe
that the cursor is permanently shown in the Zoom
Cursor mode (see more
details about Zoom Cursor);
- Click on the first point (top left) over the
image and diagonally drag to the second point
(bottom right), defining a rectangle over the image;
- Choose Apply - Draw or
. The image is zoomed inside the delimited
region. Observe that the line and column values
are presented on the Output Image Parameters.
NOTE: If you wish, you can type in directly the
values of X1,Y1 and X2,Y2 on the correspondent fields.
Then, choose Apply - Draw or .
To see the whole image again, use the button Reset or Apply
- Reset on the main menu. In this case, the
minimum and maximum values are presented.
For easier location of the interest area, use the linear
contrast over the image:
To
enhance an image:
- Load the image (or a region of interest) as
described above;
- Click on the button Enhance
. The "Enhancement" window is
presented;
- Click on the button and drag it
horizontally. When you release the mouse, the contrast
will be applied to the image. Adjust the contrast
as you wish.
After choosing the region on the image to be recorded,
save it on SPG format so it can be used on the "Spring"
module.
Pay attention when you define the output image
pixel size and sampling factor. Incorrect
values can produce incoherent output when registering the
image. TIFF e RAW images do not contain the information
about spatial resolution of the sensor used, so try to
find out or calculate the image pixel size in meters
beforehand. You will need this information.
Saving
images on SPG format:
- Select the Band(s) for the output
image;
- Select the Sampling factor. If you wish to
keep the original pixel size, use Sampling 1;
- Click on File - Salve As... or
. The window "Salvar Como" (Save as) is
presented ( see details on how
to operate it);
- Type the SPG filename and click in "Salvar"
(Save).
NOTE: When the image is from the TM-Landsat
sensor, level 5 or 6, the version of "Spring"
(3.1.1 or later) will keep the geometric correction that
already comes with this kind of image, even if you resize
or cut the image. The image
registration for this kind of image, can be
performed with only one control point.
See
also:
Digital Images
Remote Sensing
Image Registration
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