LGIA geoid grid

CMakeLists.txt

@@ -44,6 +44,7 @@ set(CPACK_SOURCE_INSTALLED_DIRECTORIES
     "${CMAKE_CURRENT_SOURCE_DIR}/hu_bme/" "."
     "${CMAKE_CURRENT_SOURCE_DIR}/is_lmi/" "."
     "${CMAKE_CURRENT_SOURCE_DIR}/jp_gsi/" "."
+    "${CMAKE_CURRENT_SOURCE_DIR}/lv_lgia/" "."
     "${CMAKE_CURRENT_SOURCE_DIR}/mx_inegi/" "."
     "${CMAKE_CURRENT_SOURCE_DIR}/nc_dittt/" "."
     "${CMAKE_CURRENT_SOURCE_DIR}/nl_nsgi/" "."

agency.json

@@ -161,6 +161,12 @@
         "agency": "Geospatial Information Authority of Japan",
         "url": "https://www.gsi.go.jp/"
     },
+    {
+        "id": "lv_lgia",
+        "country": "Latvia",
+        "agency": "Latvian Geospatial Information Agency",
+        "url": "https://www.lgia.gov.lv/"
+    },
     {
         "id": "mx_inegi",
         "country": "Mexico",

copyright_and_licenses.csv

@@ -201,6 +201,8 @@ is_lmi_ISN_vel_beta.tif,"2017-2019, National Land Survey of Iceland",CC-BY-4.0,,
 is_lmi_README.txt,Disclaimed,Public domain,,
 jp_gsi_gsigeo2011.tif,Geospatial Information Authority of Japan,CC-BY-4.0,,
 jp_gsi_README.txt,Disclaimed,Public domain,,
+lv_lgia_lv14.tif,Latvian Geospatial Information Agency,CC-BY-4.0,1.21,
+lv_lgia_README.txt,Disclaimed,Public domain,,
 mx_inegi_ggm10.tif,Instituto Nacional de Estadística Geografía e Informática (INEGI) Mexico,CC-BY-4.0,1.8,
 mx_inegi_README.txt,Disclaimed,Public domain,1.8,
 NKG,Nordic Geodetic Commission,CC-BY-4.0,,

files.geojson

@@ -203,6 +203,8 @@
 { "type": "Feature", "properties": { "url": "https://cdn.proj.org/is_lmi_Icegeoid_ISN93.tif", "name": "is_lmi_Icegeoid_ISN93.tif", "area_of_use": "Iceland", "type": "VERTICAL_OFFSET_GEOGRAPHIC_TO_VERTICAL", "source_crs_code": "EPSG:4945", "source_crs_name": "ISN93", "target_crs_code": "EPSG:8089", "target_crs_name": "ISH2004 height", "source": "National Land Survey of Iceland", "source_country": "Iceland", "source_id": "is_lmi", "source_url": "https://atlas.lmi.is/LmiData/index.php?id=626468364600", "description": "ISN93 (EPSG:4945) to ISH2004 height (EPSG:8089)", "file_size": 484461, "sha256sum": "8a588b926307ddaf1213e8b35c7b5c7e671105631cb4027a82f1488d39681631" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ -26.0, 62.5 ], [ -12.0, 62.5 ], [ -12.0, 67.5 ], [ -26.0, 67.5 ], [ -26.0, 62.5 ] ] ] } },
 { "type": "Feature", "properties": { "url": "https://cdn.proj.org/jp_gsi_README.txt", "name": "jp_gsi_README.txt", "source": "Geospatial Information Authority of Japan", "source_country": "Japan", "source_id": "jp_gsi", "source_url": "https://www.gsi.go.jp/", "file_size": 2410, "sha256sum": "6affade320a25c31569c6356b5ba18a1b942c3a32924bfea32c319c83dc82825" }, "geometry": null },
 { "type": "Feature", "properties": { "url": "https://cdn.proj.org/jp_gsi_gsigeo2011.tif", "name": "jp_gsi_gsigeo2011.tif", "area_of_use": "Japan - onshore mainland", "type": "VERTICAL_OFFSET_GEOGRAPHIC_TO_VERTICAL", "source_crs_code": "EPSG:6667", "source_crs_name": "JGD2011", "target_crs_code": "EPSG:6695", "target_crs_name": "JGD2011 (vertical) height", "source": "Geospatial Information Authority of Japan", "source_country": "Japan", "source_id": "jp_gsi", "source_url": "https://www.gsi.go.jp/", "description": "JDG2011 (EPSG:6667) to JGD2011 (vertical) height (EPSG:6695)", "file_size": 428043, "sha256sum": "1b17b754224e1a7ffc8e281591bb33840832b2a04876c51ce50959181b4102e5" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 120.0, 20.0166665 ], [ 150.0, 20.0166665 ], [ 150.0, 49.9999998 ], [ 120.0, 49.9999998 ], [ 120.0, 20.0166665 ] ] ] } },
+{ "type": "Feature", "properties": { "url": "https://cdn.proj.org/lv_lgia_README.txt", "name": "lv_lgia_README.txt", "source": "Latvian Geospatial Information Agency", "source_country": "Latvia", "source_id": "lv_lgia", "source_url": "https://www.lgia.gov.lv/", "file_size": 1799, "sha256sum": "683563f5db5475d850d5c67831654dd182a5595384dfd2b24028a84c926fb9ce" }, "geometry": null },
+{ "type": "Feature", "properties": { "url": "https://cdn.proj.org/lv_lgia_lv14.tif", "name": "lv_lgia_lv14.tif", "area_of_use": "Latvia - onshore mainland", "type": "VERTICAL_OFFSET_GEOGRAPHIC_TO_VERTICAL", "source_crs_code": "EPSG:4949", "source_crs_name": "LKS-92", "target_crs_code": "EPSG:7700", "target_crs_name": "Latvia 2000 height", "source": "Latvian Geospatial Information Agency", "source_country": "Latvia", "source_id": "lv_lgia", "source_url": "https://www.lgia.gov.lv/", "description": "LKS92 (EPSG:4949) to Latvia 2000 height (EPSG:7700)", "file_size": 36065, "sha256sum": "d20309cae5a51ce33f9937e03da074d9cbd3d99debfa8e6d974043115f2eef73", "version_added": "1.21" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 20.90014, 58.10014 ], [ 20.90014, 55.60014 ], [ 28.30014, 55.60014 ], [ 28.30014, 58.10014 ], [ 20.90014, 58.10014 ] ] ] } },
 { "type": "Feature", "properties": { "url": "https://cdn.proj.org/mx_inegi_README.txt", "name": "mx_inegi_README.txt", "source": "Instituto Nacional de Estadística, Geografía e Informática (INEGI)", "source_country": "Mexico", "source_id": "mx_inegi", "source_url": "https://www.inegi.org.mx/", "file_size": 685, "sha256sum": "be5ed155dbee5fc982c6e0ee386189473df9c44d46a090622fae001d3975985d", "version_added": "1.8" }, "geometry": null },
 { "type": "Feature", "properties": { "url": "https://cdn.proj.org/mx_inegi_ggm10.tif", "name": "mx_inegi_ggm10.tif", "area_of_use": "Mexico", "type": "VERTICAL_OFFSET_GEOGRAPHIC_TO_VERTICAL", "source_crs_code": "EPSG:6364", "source_crs_name": "Mexico ITRF2008", "target_crs_code": "EPSG:5703", "target_crs_name": "NAVD88 height", "source": "Instituto Nacional de Estadística, Geografía e Informática (INEGI)", "source_country": "Mexico", "source_id": "mx_inegi", "source_url": "https://www.inegi.org.mx/", "description": "Mexico ITRF2008 (EPSG:6364) to NAVD88 height (EPSG:5703)", "file_size": 566618, "sha256sum": "39b1ea1e2505f140655c3ee4aae65fa19e180008cc96dda79ded191a9988d651", "version_added": "1.8" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ -118.97917, 14.02083 ], [ -86.02083, 14.02083 ], [ -86.02083, 32.97917 ], [ -118.97917, 32.97917 ], [ -118.97917, 14.02083 ] ] ] } },
 { "type": "Feature", "properties": { "url": "https://cdn.proj.org/nc_dittt_README.txt", "name": "nc_dittt_README.txt", "source": "Gouvernement de Nouvelle Calédonie - DITTT", "source_country": "New Caledonia", "source_id": "nc_dittt", "source_url": "https://dittt.gouv.nc/circe-pour-la-nouvelle-caledonie", "file_size": 4131, "sha256sum": "c21366e63e45f5e335d5d9d35d3379590bc1d213114164799753d427f4083c81" }, "geometry": null },

index.html

@@ -728,6 +728,9 @@ <h2>Content</h2>
 </ul><hr><h3><a href="https://www.gsi.go.jp/">Geospatial Information Authority of Japan</a></h3><ul>
 <li><a style="word-break: break-word" href="jp_gsi_README.txt">jp_gsi_README.txt</a>. Last modified: 2020-10-28</li>
 <li><a style="word-break: break-word" href="jp_gsi_gsigeo2011.tif">jp_gsi_gsigeo2011.tif</a> - Japan - onshore mainland - JDG2011 (EPSG:6667) to JGD2011 (vertical) height (EPSG:6695). Last modified: 2020-10-28</li>
+</ul><hr><h3><a href="https://www.lgia.gov.lv/">Latvian Geospatial Information Agency</a></h3><ul>
+<li><a style="word-break: break-word" href="lv_lgia_README.txt">lv_lgia_README.txt</a>. Last modified: 2025-02-28</li>
+<li><a style="word-break: break-word" href="lv_lgia_lv14.tif">lv_lgia_lv14.tif</a> - Latvia - onshore mainland - LKS92 (EPSG:4949) to Latvia 2000 height (EPSG:7700). Last modified: 2025-02-28</li>
 </ul><hr><h3><a href="https://www.inegi.org.mx/">Instituto Nacional de Estadística, Geografía e Informática (INEGI)</a></h3><ul>
 <li><a style="word-break: break-word" href="mx_inegi_README.txt">mx_inegi_README.txt</a>. Last modified: 2021-10-07</li>
 <li><a style="word-break: break-word" href="mx_inegi_ggm10.tif">mx_inegi_ggm10.tif</a> - Mexico - Mexico ITRF2008 (EPSG:6364) to NAVD88 height (EPSG:5703). Last modified: 2021-10-07</li>

lv_lgia/.github/README.md

@@ -0,0 +1 @@
+../lv_lgia_README.txt

lv_lgia/lv_14_convert.sh

@@ -0,0 +1,46 @@
+#!/bin/bash
+
+# Ensure an input file is provided
+if [ -z "$1" ]; then
+    echo "Usage: $0 <path_to_source_file>"
+    exit 1
+fi
+
+# Get the absolute path of the input file
+SOURCE_FILE="$1"
+
+# Ensure the input file exists
+if [ ! -f "$SOURCE_FILE" ]; then
+    echo "Error: File '$SOURCE_FILE' not found."
+    exit 1
+fi
+
+# Define a temporary file for the corrected grid
+TEMP_FILE="temp_grid.dat"
+
+# Swap latitude and longitude using awk and create a temporary file
+awk '{print $2, $1, $3}' "$SOURCE_FILE" > "$TEMP_FILE"
+
+# Convert the corrected grid to a GeoTIFF
+TEMP_FILE2="temp_grid.tif"
+gdal_translate -of GTiff -a_nodata 9999 "$TEMP_FILE" "$TEMP_FILE2"
+
+# Run the vertoffset grid conversion
+OUTPUT_TIF="lv_lgia_lv14.tif"
+python3 ../grid_tools/vertoffset_grid_to_gtiff.py \
+  --description "LKS92 (EPSG:4949) to Latvia 2000 height (EPSG:7700). Converted from $SOURCE_FILE" \
+  --type "GEOGRAPHIC_TO_VERTICAL" \
+  --copyright "Derived from work by Latvian Geospatial Information Agency. CC-BY 4.0" \
+  --area-of-use "Latvia - onshore mainland" \
+  --parameter-name "geoid_undulation" \
+  --source-crs "EPSG:4949" \
+  --target-crs "EPSG:7700" \
+  "$TEMP_FILE2" "$OUTPUT_TIF"
+
+python3 ../grid_tools/check_gtiff_grid.py "$OUTPUT_TIF"
+
+# Cleanup temporary files
+rm -f "$TEMP_FILE"
+rm -f "$TEMP_FILE2"
+
+echo "Processing complete. Output saved to $OUTPUT_TIF"

lv_lgia/lv_lgia_README.txt

@@ -0,0 +1,27 @@
+# lv_lgia_README.txt
+
+The files in this section result from the conversion of datasets originating
+from [Latvian Geospatial Information Agency](https://www.lgia.gov.lv/)
+
+## Included grids
+
+### LKS92 (EPSG:4949) -> Latvia 2000 height (EPSG:7700)
+
+*Source*: [Latvian Geospatial Information Agency](https://www.lgia.gov.lv/en/latvian-quasi-geoid-model)
+*Format*: GeoTIFF converted by standard GDAL functions and optimized by grid_tools scripts
+*License*: CC-BY 4.0.
+*Horizontal CRS*: LKS92 (EPSG:4949)
+
+As of December 1, 2014, the Latvian Geospatial Information Agency (LGIA) released the new quasi-geoid model, LV′14.
+
+The validation of this quasi-geoid model was carried out by comparing its empirical height anomalies with those obtained from field measurements. These elevation anomalies are critical for geodetic software when transitioning from geodetic (ellipsoidal) to normal heights, and they are used in both global positioning systems and data processing applications.
+
+For validation, the 1st and 2nd class leveling network points, where global positioning was performed through post-processing, showed a standard deviation of height anomalies against the measured points within one sigma of up to 14 mm.
+
+The maximum height anomaly difference at the reference points reached up to 53 mm.
+
+For the leveling points in the validation network, where real-time global positioning measurements were taken, the maximum standard deviation within one sigma was up to 22 mm, with elevation anomaly differences reaching up to 65 mm.
+
+The validation results in both post-processing and real-time modes indicate that the accuracy of the LV′14 quasi-geoid model is sufficient for acquiring fundamental geospatial data needed to support state and municipal functions and tasks.
+
+*  lv_lgia_lv14.tif

travis/expected_main.lst

@@ -199,6 +199,8 @@ is_lmi_ISN_vel_beta.tif
 is_lmi_README.txt
 jp_gsi_gsigeo2011.tif
 jp_gsi_README.txt
+lv_lgia_lv14.tif
+lv_lgia_README.txt
 mx_inegi_ggm10.tif
 mx_inegi_README.txt
 nc_dittt_gr3dnc01b.tif