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remove the block adjustment window phrase
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guide/06-imagery-and-raster-analysis/orthomapping_guide_2.ipynb

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"In Part 1 of this guide, we explained what an ortho image collection is and how to create one for digital aerial imagery. At this point, the imagery has been organized and managed so that we can access all the necessary metadata, information, tools and functionality to work with our imagery, but we haven’t yet performed a bundle block adjustment <a href='#References'>[1]</a>.\n",
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"In order to understand `bundle block adjustment` better, let's first rewind on some of these terms:\n",
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" - **Tie Points** \"A tie point is a point that may not have known ground coordinates, but is visually recognizable in the overlap area between two or more images. The corresponding positions of the tie point in each overlapped image are identified and measured. The figure below shows tie points depicted as black diamonds. Some types of feature, such as large water bodies, desert areas, or cloudy areas, are difficult to find matches within the overlap areas. Since these areas can cause poor results, these areas should be excluded from the computation by defining a mask. Tie points can be entered manually using the Block Adjustment window.\" <a href=\"#References\">[4]</a> Tie points are used to minimize the misalignment between two or more images.\n",
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" - **Ground Control Points** \"Ground control points, shown as blue stars in the figure below, are identifiable features located on earth surfaces that have known ground coordinates x,y, and z. The GCPs can be prepared in three ways: (1) Survey points that come in a form of x,y,z. You can input the coordinates into the control point table using the Block Adjustment window. (2) Ortho rectified image chips. If you have image chips for some features or locations within your block, create a mosaic dataset from these image chips, and compute control points from your mosaic dataset using the Compute Control Points tool, then add it to the control point table. And (3) Ortho rectified image service. You can also compute control points based on a single ortho rectified image or image service, and add them to the control point table check points. Check points are known ground control points, but instead of them being used in computing adjustment, they are used in checking the accuracy of adjustment computation.\" <a href=\"#References\">[4]</a> GCPs are used to georeference the images to the ground.\n",
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" - **Tie Points** \"A tie point is a point that may not have known ground coordinates, but is visually recognizable in the overlap area between two or more images. The corresponding positions of the tie point in each overlapped image are identified and measured. The figure below shows tie points depicted as black diamonds.\" <a href=\"#References\">[4]</a> Tie points are used to minimize the misalignment between two or more images.\n",
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" - **Ground Control Points** \"Ground control points, shown as blue stars in the figure below, are identifiable features located on earth surfaces that have known ground coordinates x,y, and z.\" Generally, the GCPs can be prepared in three ways: (1) Survey points that come in a form of x,y,z. You can input the coordinates into the control point table manually. (2) Ortho rectified image chips. If you have image chips for some features or locations within your block, create a mosaic dataset from these image chips, and compute control points from your mosaic dataset using the Compute Control Points tool, then add it to the control point table. And (3) Ortho rectified image service. You can also compute control points based on a single ortho rectified image or image service, and add them to the control point table check points. \"Check points are known ground control points, but instead of them being used in computing adjustment, they are used in checking the accuracy of adjustment computation.\" <a href=\"#References\">[4]</a> GCPs are used to georeference the images to the ground.\n",
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" - **Block** \"Mosaicking satellite images or aerial photographs for an area or a project\", is called a block. For example, the nine overlapping images or photographs are for a single area, which can be defined as a block.\n",
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" - **Block Adjustment** A Process that consists of the three key parts - Tie points, GCPs, and Triangulation (which computes the transformation by minimizing and distributing the errors among images and control points)."
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