New aerial and satellite images were acquired within the specified area of interest
(AOI), and where available, archive satellite images (not older than 6 months from
the date the contract was signed) were utilized.
For each block, a separate flight plan was prepared using basic parameters for the
project: GSD 0,30 m, forward overlap 60%, and side overlap 30%. The flight
planning software (TrackAir) creates initial flight lines on a flat projected area. It
is then adjusts line spacing with the support of implemented DEM (DEM from the
Shuttle Radar Topography Mission) into the planning software, in order to compensate for the ground elevation, which directly influences the exposure parameters of
the aerial camera, i.e., time between exposures, distance between flight lines, and
flying height above ground level.
As the result of flight planning, 67 separate flight plans were prepared for a
Vexcel UltraCam Xp 100 mm camera and 67 for a Vexcel UltraCam Eagle 80 mm
camera. With the introduction of two Vexcel UltraCam X cameras in the 2015
season, an additional 15 flight plans were created for this camera type. In 2016,
seven flight plans were prepared: five blocks for the Vexcel UltraCam X 100 mm and
two blocks for the Vexcel UltraCam Eagle 210 mm.
13.3.1.2 Post-processing of Aerial Imagery (AI)
All of the camera systems used to capture the aerial photography for the LPIS project
were Vexcel/Microsoft UltraCam types, which enabled unified and coherent image
processing and orthophoto production as all images were processed in a single
software environment: the Vexcel/Microsoft UltraMap software suite. The software
includes features for managing data download, backup, and distributed processing
using the load-balancing technique and also allows interactive data visualization and
quality control of the processed aerial images. Moreover, a high level of automatization prevents human error and allows quality control to be conducted quickly and
effectively.
UltraCam images are captured as separate sub-images: four panchromatic and
red, green, blue (RGB) and near-infrared (NIR); during a series of post-processing,
the sub-images are joined and merged to high-resolution four-band images (RGBI).
After the completion of each photo flight mission, the raw images (Level 00) were
downloaded from the cameras to a portable copy station, where the images were
initially checked and copied to external USB hard drives. The disks were sent by
secured courier to the production office in Ankara, where further processing took
place.
After copying the Level 00 images to the file storage server, the images were
processed to the Level 02 stage. Image processing consists of stitching, blending,
and registration steps and geometric corrections. The images are processed to highresolution 16-bit panchromatic and low-resolution RGBI format. At this stage, the
images were checked visually for the existence of clouds, shadows, haze, or other
objects that can cover ground features. In addition, stitching quality and completeness of all data from different cones in the camera were checked. The results from the
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H. Erden and M. Aslan
(AOI), and where available, archive satellite images (not older than 6 months from
the date the contract was signed) were utilized.
For each block, a separate flight plan was prepared using basic parameters for the
project: GSD 0,30 m, forward overlap 60%, and side overlap 30%. The flight
planning software (TrackAir) creates initial flight lines on a flat projected area. It
is then adjusts line spacing with the support of implemented DEM (DEM from the
Shuttle Radar Topography Mission) into the planning software, in order to compensate for the ground elevation, which directly influences the exposure parameters of
the aerial camera, i.e., time between exposures, distance between flight lines, and
flying height above ground level.
As the result of flight planning, 67 separate flight plans were prepared for a
Vexcel UltraCam Xp 100 mm camera and 67 for a Vexcel UltraCam Eagle 80 mm
camera. With the introduction of two Vexcel UltraCam X cameras in the 2015
season, an additional 15 flight plans were created for this camera type. In 2016,
seven flight plans were prepared: five blocks for the Vexcel UltraCam X 100 mm and
two blocks for the Vexcel UltraCam Eagle 210 mm.
13.3.1.2 Post-processing of Aerial Imagery (AI)
All of the camera systems used to capture the aerial photography for the LPIS project
were Vexcel/Microsoft UltraCam types, which enabled unified and coherent image
processing and orthophoto production as all images were processed in a single
software environment: the Vexcel/Microsoft UltraMap software suite. The software
includes features for managing data download, backup, and distributed processing
using the load-balancing technique and also allows interactive data visualization and
quality control of the processed aerial images. Moreover, a high level of automatization prevents human error and allows quality control to be conducted quickly and
effectively.
UltraCam images are captured as separate sub-images: four panchromatic and
red, green, blue (RGB) and near-infrared (NIR); during a series of post-processing,
the sub-images are joined and merged to high-resolution four-band images (RGBI).
After the completion of each photo flight mission, the raw images (Level 00) were
downloaded from the cameras to a portable copy station, where the images were
initially checked and copied to external USB hard drives. The disks were sent by
secured courier to the production office in Ankara, where further processing took
place.
After copying the Level 00 images to the file storage server, the images were
processed to the Level 02 stage. Image processing consists of stitching, blending,
and registration steps and geometric corrections. The images are processed to highresolution 16-bit panchromatic and low-resolution RGBI format. At this stage, the
images were checked visually for the existence of clouds, shadows, haze, or other
objects that can cover ground features. In addition, stitching quality and completeness of all data from different cones in the camera were checked. The results from the
240
H. Erden and M. Aslan