Greater Toronto Area (GTA) Orthophotography Project 2013Coordinate system: 2958 Abstract:The imagery used to produce this product was acquired by First Base Solutions Between April 4 2013 and May 4 2013. The imagery covers the Greater Toronto Area (GTA). The image files are available in TIFF and JPEG2000 format, and are provided as separate image services. First Base Solutions created a digital full resolution colour orthophoto image of every photograph using the adjusted digital images and the digital elevation model as source material. All final ortho image processing was completed using a combination of PCI and Intergraph software. Once the adjusted image orientation data is imported, the remaining data required to produce the orthophotos was input. This included the camera calibration data, the control data and the digital elevation model. The orthorectification process is done on the Level-3 RGBI images within PCI. Intergraph OrthoPro uses a feathering algorithm to blend the images to produce seamless mosaics. Seam lines are generated automatically based on selecting the pixels with the minimum difference of colour values between two images as the cutline pixels. |