Encapsulates a GEOTiff images with geo referenced meta information. More...

#include <CVImageGeoTiff.h>

Inheritance diagram for CVImageGeoTiff:

Public Member Functions
	CVImageGeoTiff ()

	~CVImageGeoTiff ()

void	loadGeoTiff (const string &filename)
	Loads a GEOTiff file into the OpenCV image matrix. More...

CVVec3d	upperLeftLatLonAlt () const

CVVec3d	lowerRightLatLonAlt () const

float	getAltitudeAtLatLon (double lat, double lon) const
	Returns the altitude in m at the given position in WGS84 latitude-longitude. More...

Public Member Functions inherited from CVImage
	CVImage ()
	Default constructor. More...

	CVImage (int width, int height, CVPixelFormatGL format, string name)
	Constructor for empty image of a certain format and size. More...

	CVImage (const string &imageFilename, bool flipVertical=true, bool loadGrayscaleIntoAlpha=false)
	Constructor for image from file. More...

	CVImage (CVImage &srcImage)
	Copy constructor from a source image. More...

	CVImage (const CVVVec3f &colors)
	Creates a 1D image from a CVVec3f color vector. More...

	CVImage (const CVVVec4f &colors)

	~CVImage ()

void	clearData ()
	Deletes all data and resets the image parameters. More...

bool	allocate (int width, int height, CVPixelFormatGL pixelFormatGL, bool isContinuous=true)
	Memory allocation function. More...

void	load (const string &filename, bool flipVertical=true, bool loadGrayscaleIntoAlpha=false)
	Loads the image with the appropriate image loader. More...

bool	load (int inWidth, int inHeight, CVPixelFormatGL srcPixelFormatGL, CVPixelFormatGL dstPixelFormatGL, uchar *data, bool isContinuous, bool isTopLeft)
	loads an image from a memory with format change. More...

void	savePNG (const string &filename, int compressionLevel=6, bool flipY=true, bool convertBGR2RGB=true)
	Save as PNG at a certain compression level (0-9) More...

void	saveJPG (const string &filename, int compressionLevel=95, bool flipY=true, bool convertBGR2RGB=true)
	Save as JPG at a certain compression level (0-100) More...

CVVec4f	getPixeli (int x, int y)
	getPixeli returns the pixel color at the integer pixel coordinate x, y More...

CVVec4f	getPixelf (float x, float y)

void	setPixeli (int x, int y, CVVec4f color)
	setPixeli sets the RGB pixel color at the integer pixel coordinate x, y More...

void	setPixeliRGB (int x, int y, CVVec3f color)
	setPixeli sets the RGB pixel color at the integer pixel coordinate x, y More...

void	setPixeliRGB (int x, int y, CVVec4f color)
	setPixeli sets the RGB pixel color at the integer pixel coordinate x, y More...

void	setPixeliRGBA (int x, int y, CVVec4f color)
	setPixeli sets the RGBA pixel color at the integer pixel coordinate x, y More...

void	resize (int width, int height)

void	convertTo (int cvDataType)
	Converts the data type of the cvMat. More...

void	flipX ()
	Flip X coordinates used to make JPEGs from top-left to bottom-left images. More...

void	flipY ()
	Flip Y coordinates used to make JPEGs from top-left to bottom-left images. More...

void	fill (uchar r, uchar g, uchar b)
	Fills the image with a certain rgb color. More...

void	fill (uchar r, uchar g, uchar b, uchar a)
	Fills the image with a certain rgba color. More...

void	crop (float targetWdivH, int &cropW, int &cropH)

string	name ()

CVMat	cvMat () const

uchar *	data ()

bool	empty () const

uint	width ()

uint	height ()

uint	bytesPerPixel ()

uint	bytesPerLine ()

uint	bytesPerImage ()

uint	bytesInFile ()

CVPixelFormatGL	format ()

string	formatString ()

string	path ()

Private Attributes
CVVec3d	_upperleftLatLonAlt

CVVec3d	_lowerRightLatLonAlt
	Upper-left corner of DEM in WGS84 coords. More...

double	_noDataValue
	Lower-right corner of DEM in WGS84 coords. More...

Additional Inherited Members
Static Public Member Functions inherited from CVImage
static CVPixelFormatGL	cvType2glPixelFormat (int cvType)
	Converts OpenCV mat type to OpenGL pixel format. More...

static int	glPixelFormat2cvType (CVPixelFormatGL pixelFormatGL)
	Converts OpenGL pixel format to OpenCV mat type. More...

static string	formatString (CVPixelFormatGL pixelFormatGL)
	Returns the pixel format as string. More...

static string	typeString (int cvMatTypeInt)
	Returns the cv::Mat.type()) as string. More...

Static Protected Member Functions inherited from CVImage
static uint	bytesPerPixel (CVPixelFormatGL pixelFormat)
	Returns the NO. of bytes per pixel for the passed pixel format. More...

static uint	bytesPerLine (uint width, CVPixelFormatGL pixelFormat, bool isContinuous=false)
	Returns the NO. of bytes per image line for the passed pixel format. More...

Protected Attributes inherited from CVImage
string	_name
	Image name (e.g. from the filename) More...

CVMat	_cvMat
	OpenCV mat matrix image type. More...

CVPixelFormatGL	_format
	OpenGL pixel format. More...

uint	_bytesPerPixel
	Number of bytes per pixel. More...

uint	_bytesPerLine
	Number of bytes per line (stride) More...

uint	_bytesPerImage
	Number of bytes per image. More...

uint	_bytesInFile
	Number of bytes in file. More...

string	_path
	path on the filesystem More...

Detailed Description

Encapsulates a GEOTiff images with geo referenced meta information.

A GEOTiff image can hold per pixel the height information of a "rectangular" area on earth that is defined with upper-left and lower-left corner in longitude and latitude coordinates. With the loadGeoTiff function only GeoTiffs with WGS84 (EPSG 4326) coordinates can be loaded. GeoTiff with other coordinate reference systems e.g. the Swiss LV95 can be converted first in tools such as QGIS. Because we can not load the meta information with OpenCV we have to store them in a separate json file with the same name. They are generated with a tool that comes with QGIS as follows: gdalinfo -json DTM-Aventicum-WGS84.tif > DTM-Aventicum-WGS84.json

Definition at line 27 of file CVImageGeoTiff.h.

Constructor & Destructor Documentation

◆ CVImageGeoTiff()

CVImageGeoTiff::CVImageGeoTiff ( )

Definition at line 18 of file CVImageGeoTiff.cpp.

 {
     _noDataValue = 0.0;
 }

◆ ~CVImageGeoTiff()

CVImageGeoTiff::~CVImageGeoTiff ( )

Definition at line 23 of file CVImageGeoTiff.cpp.

 {
     clearData();
 }

Member Function Documentation

◆ getAltitudeAtLatLon()

float CVImageGeoTiff::getAltitudeAtLatLon	(	double	lat,
		double	lon
	)		const

Returns the altitude in m at the given position in WGS84 latitude-longitude.

Definition at line 137 of file CVImageGeoTiff.cpp.

 {
     double dLatDEG   = _upperleftLatLonAlt[0] - _lowerRightLatLonAlt[0];
     double dLonDEG   = _lowerRightLatLonAlt[1] - _upperleftLatLonAlt[1];
     double latPerPix = dLatDEG / (double)_cvMat.rows;
     double lonPerPix = dLonDEG / (double)_cvMat.cols;
  
     double offsetLat = latDEG - _lowerRightLatLonAlt[0];
     double offsetLon = lonDEG - _upperleftLatLonAlt[1];
  
     double pixPosLat = offsetLat / latPerPix; // pixels from bottom
     double pixPosLon = offsetLon / lonPerPix; // pixels from left
  
     // pixels are top-left coordinates in OpenCV
     pixPosLat = _cvMat.rows - pixPosLat;
  
     if (pixPosLat < 0.0 || pixPosLat > _cvMat.rows - 1.0)
     {
         SL_LOG("Invalid pixPosLat %3.2f", pixPosLat);
         pixPosLat = 0;
     }
     if (pixPosLon < 0.0 || pixPosLon > _cvMat.cols - 1.0)
     {
         SL_LOG("Invalid pixPosLon %3.2f", pixPosLon);
         pixPosLon = 0;
     }
  
     // get subpixel accurate interpolated height value
     cv::Point2f pt((float)pixPosLon, (float)pixPosLat);
     cv::Mat     patch;
     cv::getRectSubPix(_cvMat, cv::Size(1, 1), pt, patch);
  
     float heightMatPix    = _cvMat.at<float>((int)pixPosLat, (int)pixPosLon);
     float heightMatSubPix = patch.at<float>(0, 0);
     return heightMatSubPix;
 }

◆ loadGeoTiff()

void CVImageGeoTiff::loadGeoTiff ( const string & filename )

Loads a GEOTiff file into the OpenCV image matrix.

Definition at line 29 of file CVImageGeoTiff.cpp.

 {
 #ifndef __EMSCRIPTEN__
     string msg;
  
     // check if the GEOTiff file exists
     if (!Utils::fileExists(geoTiffFile))
     {
         msg = "CVImageGeoTiff::loadGeoTiff: File not found: " + geoTiffFile;
         Utils::exitMsg("SLProject",
                        msg.c_str(),
                        __LINE__,
                        __FILE__);
     }
  
     // check if the GEOTiff json file exists
     string jsonFileName = Utils::getPath(geoTiffFile) +
                           Utils::getFileNameWOExt(geoTiffFile) +
                           ".json";
     if (!Utils::fileExists(jsonFileName))
     {
         msg = "CVImageGeoTiff::loadGeoTiff: JSON File not found: " + jsonFileName;
         msg += "\nA GEOTiff file must have a JSON file aside with the same name.";
         msg += "\nYou can generate this JSON file with the tool gdalinfo.";
         Utils::exitMsg("SLProject",
                        msg.c_str(),
                        __LINE__,
                        __FILE__);
     }
  
     // Read the geo tiff image with OpenCV
     cv::Mat imgGeoTiff = cv::imread(geoTiffFile,
                                     cv::IMREAD_LOAD_GDAL | cv::IMREAD_ANYDEPTH);
  
     if (imgGeoTiff.type() != CV_32FC1)
         Utils::exitMsg("SLProject",
                        "GEOTiff image must be of 32-bit float type.",
                        __LINE__,
                        __FILE__);
  
     // Read the JSON file
     std::ifstream  jsonFile(jsonFileName);
     json           jsonData;
     string         description;
     string         geocsc;
     vector<int>    size;
     vector<double> upperLeft;
     vector<double> lowerRight;
  
     // Reading values from json
     try
     {
         jsonFile >> jsonData;
         description  = jsonData["description"].get<string>();
         geocsc       = jsonData["coordinateSystem"]["wkt"].get<string>();
         size         = jsonData["size"].get<vector<int>>();
         upperLeft    = jsonData["cornerCoordinates"]["upperLeft"].get<vector<double>>();
         lowerRight   = jsonData["cornerCoordinates"]["lowerRight"].get<vector<double>>();
         _noDataValue = jsonData["bands"][0]["noDataValue"].get<double>();
     }
     catch (json::exception& e)
     {
         msg = "Error reading JSON-File: " + jsonFileName;
         msg += "\nException: ";
         msg += e.what();
         Utils::exitMsg("SLProject",
                        msg.c_str(),
                        __LINE__,
                        __FILE__);
     }
  
     // Check some correspondences between image file an json file
     if (size.size() < 2 || size[0] != imgGeoTiff.cols || size[1] != imgGeoTiff.rows)
     {
         msg = "Mismatch between geotiff image size and size json tag:";
         msg += "\nGEOTiff image width : " + to_string(imgGeoTiff.cols);
         msg += "\nGEOTiff image height: " + to_string(imgGeoTiff.rows);
         msg += "\nJSON Size tag[0]    : " + to_string(size[0]);
         msg += "\nJSON Size tag[1]    : " + to_string(size[1]);
         Utils::exitMsg("SLProject",
                        msg.c_str(),
                        __LINE__,
                        __FILE__);
     }
  
     if (!Utils::containsString(geocsc, "WGS 84") &&
         !Utils::containsString(geocsc, "WGS_1984"))
     {
         msg = "GeoTiff file seams not have WGS84 coordinates.";
         Utils::exitMsg("SLProject",
                        msg.c_str(),
                        __LINE__,
                        __FILE__);
     }
  
     _cvMat  = imgGeoTiff.clone();
     _format = cvType2glPixelFormat(imgGeoTiff.type());
  
     _upperleftLatLonAlt[0]  = upperLeft[1];           // We store first latitude in degrees! (N)
     _upperleftLatLonAlt[1]  = upperLeft[0];           // and then longitude in degrees (W)
     _upperleftLatLonAlt[2]  = _cvMat.at<float>(0, 0); // and then altitude in m from the image
     _lowerRightLatLonAlt[0] = lowerRight[1];          // we store first latitude in degrees! (S)
     _lowerRightLatLonAlt[1] = lowerRight[0];          // and then longitude in degrees (E)
     _lowerRightLatLonAlt[2] = _cvMat.at<float>(_cvMat.rows - 1, _cvMat.cols - 1);
 #endif
 }

◆ lowerRightLatLonAlt()

CVVec3d CVImageGeoTiff::lowerRightLatLonAlt ( ) const

inline

Definition at line 35 of file CVImageGeoTiff.h.

35 { return _lowerRightLatLonAlt; }

◆ upperLeftLatLonAlt()

CVVec3d CVImageGeoTiff::upperLeftLatLonAlt ( ) const

inline

Definition at line 34 of file CVImageGeoTiff.h.

34 { return _upperleftLatLonAlt; }

Member Data Documentation

◆ _lowerRightLatLonAlt

CVVec3d CVImageGeoTiff::_lowerRightLatLonAlt

private

Upper-left corner of DEM in WGS84 coords.

Definition at line 40 of file CVImageGeoTiff.h.

◆ _noDataValue

double CVImageGeoTiff::_noDataValue

private

Lower-right corner of DEM in WGS84 coords.

Definition at line 41 of file CVImageGeoTiff.h.

◆ _upperleftLatLonAlt

CVVec3d CVImageGeoTiff::_upperleftLatLonAlt

private

Definition at line 39 of file CVImageGeoTiff.h.

The documentation for this class was generated from the following files:

Public Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ CVImageGeoTiff()

◆ ~CVImageGeoTiff()

Member Function Documentation

◆ getAltitudeAtLatLon()

◆ loadGeoTiff()

◆ lowerRightLatLonAlt()

◆ upperLeftLatLonAlt()

Member Data Documentation

◆ _lowerRightLatLonAlt

◆ _noDataValue

◆ _upperleftLatLonAlt