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Análisis GDAL

Aspecto

Descripción

Generates an aspect map from any GDAL-supported elevation raster. Aspect is the compass direction that a slope faces. The pixels will have a value from 0-360° measured in degrees from north indicating the azimuth. On the northern hemisphere, the north side of slopes is often shaded (small azimuth from 0°-90°), while the southern side receives more solar radiation (higher azimuth from 180°-270°). The algorithm is derived from the GDAL DEM utility .

Parametros

Capa de entrada [raster]
Elevation raster layer.
Numero de banda [number]

The number of a band containing elevation values.

Predeterminado: 1

Clacular bordes [boolean]

Generates edges from the elevation raster.

Predeterminado: False

Uso Zevenbergen y fórmula Thorne (en lugar de un Horn's) [boolean]

Activates Zevenbergen&Thorne formula for smooth landscapes.

Predeterminado: False

Devolver ángulo trigonométrico (en lugar de azimut) [boolean]

Activating the trigonometric angle results in different categories: 0° (=East), 90° (North), 180° (=West), 270° (=South).

Predeterminado: False

Return 0 for flat (instead of -9999) [boolean]

Activating this option will insert a 0-value for the value -9999 on flat areas.

Predeterminado: False

Salidas

Archivo de salida [raster]
Output raster with angle values in degrees.

Uso de la consola

processing.runalg('gdalogr:aspect', input, band, compute_edges, zevenbergen, trig_angle, zero_flat, output)

Ver también

Relieve de color

Descripción

Generates a color relief map from any GDAL-supported elevation raster. Color reliefs can particularly be used to depict elevations. The Algorithm outputs a 4-band raster with values computed from the elevation and a text-based color configuration file. By default, the colors between the given elevation values are blended smoothly and the result is a nice colorized elevation raster. The algorithm is derived from the GDAL DEM utility .

Parametros

Capa de entrada [raster]
Elevation raster layer.
Numero de banda [number]

The number of a band containing elevation values.

Predeterminado: 1

Clacular bordes [boolean]

Generates edges from the elevation raster.

Predeterminado: False

Archivo de configuración de color [file]
A text-based color configuration file.
Modo de emparejamiento [selection]

The “0,0,0,0” RGBA mode results in color interpolation whereas the Exact color and Nearest color modes avoid interpolation of values that don’t match an index of the color configuration file.

Opciones:

  • 0 — “0,0,0,0” RGBA
  • 1 — Color exacto

  • 2 — Color más cercano

Predeterminado: 0

Salidas

Archivo de salida [raster]
A 4-band output raster.

Uso de la consola

processing.runalg('gdalogr:colorrelief', input, band, compute_edges, color_table, match_mode, output)

Ver también

Rellenar sin datos

Descripción

Fill raster regions with no data values by interpolation from edges. The values for the no-data regions are calculated by the sourrounding pixel values using inverse distance weighting. After the interpolation a smoothing of the results takes placce. Input can be any GDAL-supported raster layer. This algorithm is generally suitable for interpolating missing regions of fairly continuously varying rasters (such as elevation models for instance). It is also suitable for filling small holes and cracks in more irregularly varying images (like airphotos). It is generally not so great for interpolating a raster from sparse point data. The algorithm is derived from the GDAL fillnodata utility .

Parametros

Capa de entrada [raster]

Capa ráster.

Distancia de búsqueda [number]

The number of pixels to search in all directions to interpolate from.

Predeterminado: 100

Iteraciones suaves [number]

The number of 3x3 filter passes to run (0 or more) to smoothen the results of the interpolation.

Predeterminado: 0

Banda sobre la que opera [number]

The band to operate on. Nodata values must be represented by the value 0.

Predeterminado: 1

Mascara de validación [raster]

Opcional

Una máscara que define cuáles áreas serán llenadas.

No utilizar la máscara de validación predeterminada [boolean]

Activates the user-defined validity mask.

Predeterminado: False

Salidas

Capa de salida [raster]

Entregar ráster en cualquier formato soportado por GDAL.

Uso de la consola

processing.runalg('gdalogr:fillnodata', input, distance, iterations, band, mask, no_default_mask, output)

Ver también

Cuadrícula (Desplazamiento medio)

Descripción

The Moving Average is a simple data averaging algorithm. It uses a moving window of elliptic form to search values and averages all data points within the window. Search ellipse can be rotated by specified angle, the center of ellipse located at the grid node. Also the minimum number of data points to average can be set, if there are not enough points in window, the grid node considered empty and will be filled with specified NODATA value.

Parametros

Capa de entrada [vector: point]

Capa vector punto

Campo Z [tablefield: numeric]
Field for the interpolation (Optional)
Radius 1 [number]

The first radius (X axis if rotation angle is 0) of search ellipse.

Por defecto: 0.0

Radio 2 [number]

The second radius (Y axis if rotation angle is 0) of search ellipse.

Por defecto: 0.0

Min de puntos [number]

Minimum number of data points to average. If less amount of points found the grid node considered empty and will be filled with NODATA marker.

Por defecto: 0.0

“Angulo” [número]

Angle of ellipse rotation in degrees. Ellipse rotated counter clockwise.

Por defecto: 0.0

Sin datos [number]

Sin marcador de datos para llenar puntos vacíos.

Por defecto: 0.0

Tipo de ráster de salida [selection]

Tipo de archivo ráster

Opciones:

  • 0 — Byte
  • 1 — Int16
  • 2 — UInt16
  • 3 — UInt32
  • 4 — Int32
  • 5 — Flotante32

  • 6 — Float64
  • 7 — CInt16
  • 8 — CInt32
  • 9 — CFloat32
  • 10 — CFloat64

Predeterminado: 5

Salidas

Archivo de salida [raster]

Archivo ráster interpolado

Uso de la consola

processing.runalg('gdalogr:gridaverage', input, z_field, radius_1, radius_2, min_points, angle, nodata, rtype, output)

Ver también

GDAL grid tutorial

Cuadrícula (Métrica de los datos)

Descripción

Este algoritmo calcula algunas métricas de datos usando la ventana y geometría de grid de salida especificadas.

Parametros

Capa de entrada [vector: point]

Capa vector punto

Campo Z [tablefield: numeric]
Field for the interpolation (Optional)
Métricas [selección]

Lista de métricas disponibles:

Opciones:

  • 0 — Minimum, minimum value found in grid node search ellipse.
  • 1 — Maximum, maximum value found in grid node search ellipse
  • 2 — Range, a difference between the minimum and maximum values found in grid node search ellipse
  • 3 — Count, a number of data points found in grid node search ellipse
  • 4 — Average distance, an average distance between the grid node (center of the search ellipse) and all of the data points found in grid node search ellipse
  • 5 — Average distance between points, an average distance between the data points found in grid node search ellipse. The distance between each pair of points within ellipse is calculated and average of all distances is set as a grid node value

Predeterminado: 0

Radius 1 [number]

The first radius (X axis if rotation angle is 0) of search ellipse. Set this parameter to zero to use whole point array

Por defecto: 0.0

Radio 2 [number]

The second radius (Y axis if rotation angle is 0) of search ellipse. Set this parameter to zero to use whole point array

Por defecto: 0.0

Min de puntos [number]

Minimum number of data points to use. If less amount of points found the grid node considered empty and will be filled with NODATA marker.

This is only used if search ellipse is set (both radii are non-zero)

Por defecto: 0.0

“Angulo” [número]

Angle of search ellipse rotation in degrees (counter clockwise)

Por defecto: 0.0

Sin datos [number]

NODATA marker to fill empty points

Por defecto: 0.0

Tipo de ráster de salida [selection]

Tipo de archivo ráster

Opciones:

  • 0 — Byte
  • 1 — Int16
  • 2 — UInt16
  • 3 — UInt32
  • 4 — Int32
  • 5 — Flotante32

  • 6 — Float64
  • 7 — CInt16
  • 8 — CInt32
  • 9 — CFloat32
  • 10 — CFloat64

Predeterminado: 5

Salidas

Archivo de salida [raster]

Archivo ráster interpolado

Uso de la consola

processing.runalg('gdalogr:griddatametrics', input, z_field, metric, radius_1, radius_2, min_points, angle, nodata, rtype, output)

Ver también

GDAL grid tutorial

Cuadrícula (Distancia inversa a una potencia)

Descripción

The Inverse Distance to a Power gridding method is a weighted average interpolator.

You should supply the input arrays with the scattered data values including coordinates of every data point and output grid geometry. The function will compute interpolated value for the given position in output grid.

Parametros

Capa de entrada [vector: point]

Capa vector punto

Campo Z [tablefield: numeric]

Capa para la interpolación (Opcional).

Potencia [número]

Poder de peso

Predeterminado: 2.0

Suavizar [number]

Smoothing parameter

Por defecto: 0.0

Radius 1 [number]

The first radius (X axis if rotation angle is 0) of search ellipse

Por defecto: 0.0

Radio 2 [number]

The second radius (Y axis if rotation angle is 0) of search ellipse

Por defecto: 0.0

Max points [number]

Maximum number of data points to use.

Do not search for more points than this number. If less amount of points found the grid node considered empty and will be filled with NODATA marker

Por defecto: 0.0

Min de puntos [number]

Minimum number of data points to use.

If less amount of points found the grid node considered empty and will be filled with NODATA marker

Por defecto: 0.0

“Angulo” [número]

Angle of ellipse rotation in degrees.

Ellipse rotated counter clockwise.

Por defecto: 0.0

Sin datos [number]

No data marker to fill empty points

Por defecto: 0.0

Tipo de ráster de salida [selection]

Tipo de archivo ráster

Opciones:

  • 0 — Byte
  • 1 — Int16
  • 2 — UInt16
  • 3 — UInt32
  • 4 — Int32
  • 5 — Flotante32

  • 6 — Float64
  • 7 — CInt16
  • 8 — CInt32
  • 9 — CFloat32
  • 10 — CFloat64

Predeterminado: 5

Salidas

Archivo de salida [raster]

Archivo ráster interpolado

Uso de la consola

processing.runalg('gdalogr:gridinvdist', input, z_field, power, smothing, radius_1, radius_2, max_points, min_points, angle, nodata, rtype, output)

Ver también

GDAL grid tutorial

Cuadrícula (Vecino más próximo)

Descripción

The Nearest Neighbor method doesn’t perform any interpolation or smoothing, it just takes the value of nearest point found in grid node search ellipse and returns it as a result. If there are no points found, the specified NODATA value will be returned.

Parametros

Capa de entrada [vector: point]

Capa vector punto

Campo Z [tablefield: numeric]

Capa para la interpolación (Opcional).

Radius 1 [number]

The first radius (X axis if rotation angle is 0) of search ellipse.

Por defecto: 0.0

Radio 2 [number]

The second radius (Y axis if rotation angle is 0) of search ellipse.

Por defecto: 0.0

“Angulo” [número]

Angle of ellipse rotation in degrees. Ellipse rotated counter clockwise.

Por defecto: 0.0

Sin datos [number]

Sin marcador de datos para llenar puntos vacíos.

Por defecto: 0.0

Tipo de ráster de salida [selection]

Tipo de archivo ráster

Opciones:

  • 0 — Byte
  • 1 — Int16
  • 2 — UInt16
  • 3 — UInt32
  • 4 — Int32
  • 5 — Flotante32

  • 6 — Float64
  • 7 — CInt16
  • 8 — CInt32
  • 9 — CFloat32
  • 10 — CFloat64

Predeterminado: 5

Salidas

Archivo de salida [raster]

Archivo ráster interpolado

Uso de la consola

processing.runalg('gdalogr:gridnearestneighbor', input, z_field, radius_1, radius_2, angle, nodata, rtype, output)

Ver también

GDAL grid tutorial

Mapa de Sombras (Hillshade)

Descripción

Outputs a raster with a nice shaded relief effect. It’s very useful for visualizing the terrain. You can optionally specify the azimuth and altitude of the light source, a vertical exaggeration factor and a scaling factor to account for differences between vertical and horizontal units. The algorithm is derived from the GDAL DEM utility .

Parametros

Capa de entrada [raster]
Elevation raster layer.
Numero de banda [number]

Band containing the elevation information.

Predeterminado: 1

Clacular bordes [boolean]

Generates edges from the elevation raster.

Predeterminado: False

Uso Zevenbergen y fórmula Thorne (en lugar de un Horn's) [boolean]

Activates Zevenbergen&Thorne formula for smooth landscapes.

Predeterminado: False

Facto Z (exageración vertical) [number]

The factor exaggerates the height of the output elevation raster.

Por defecto: 1.0

Escala (ratio de vertical. unidades para horizontal) [number]

The ratio of vertical units to horizontal units.

Por defecto: 1.0

Azimut de la luz [number]

Defines the azimuth of the light shining on the elevation raster in degrees. If it comes from the top of the raster the value is 0, if it comes from the east it is 90 a.s.o. .

Por defecto: 315.0

Altitud de la luz [number]

Defines the altitude of the light, in degrees. 90 if the light comes from above the elevation raster, 0 if it is raking light.

Por defecto: 45.0

Salidas

Archivo de salida [raster]

Ráster de salida.

Uso de la consola

processing.runalg('gdalogr:hillshade', input, band, compute_edges, zevenbergen, z_factor, scale, azimuth, altitude, output)

Ver también

Casi negro

Descripción

Convert nearly black/white borders to black.

This utility will scan an image and try to set all pixels that are nearly or exactly black, white or one or more custom colors around the collar to black or white. This is often used to “fix up” lossy compressed airphotos so that color pixels can be treated as transparent when mosaicking

Parametros

Capa de entrada [raster]
Raster file in input
How far from black (white) [number]

Select how far from black, white or custom colors the pixel values can be and still considered near black, white or custom color

Predeterminado: 15

Search for nearly white pixels instead of nearly black [boolean]

Search for nearly white (255) pixels instead of nearly black pixels

Predeterminado: False

Salidas

Capa de salida [raster]
Raster file in output

Uso de la consola

processing.runalg('gdalogr:nearblack', input, near, white, output)

Ver también

GDAL nearblack

Proximidad (distancia ráster)

Descripción

The proximity algorithm generates a raster proximity map indicating the distance from the center of each pixel to the center of the nearest pixel identified as a target pixel. Target pixels are those in the source raster for which the raster pixel value is in the set of target pixel values.

Parametros

Capa de entrada [raster]
Raster in input
Valores [string]

A list of target pixel values in the source image to be considered target pixels. If not specified, all non-zero pixels will be considered target pixels.

Por defecto: (no establecer)

Unidades de distancia [selection]

Indicate whether distances generated should be in pixel or georeferenced coordinates.

Opciones:

  • 0 — GEO
  • 1 — PIXEL

Predeterminado: 0

Max dist (negative value to ignore) [number]

The maximum distance to be generated. The nodata value will be used for pixels beyond this distance. If a nodata value is not provided, the output band will be queried for its nodata value.

If the output band does not have a nodata value, then the value 65535 will be used. Distance is interpreted in pixels unless distunits GEO is specified

Predeterminado: -1

No data (negative value to ignore) [number]

Specify a nodata value to use for the destination proximity raster

Predeterminado: -1

Valor buf fijo (valor negativo a ignorar) [number]

Specify a value to be applied to all pixels that are within the -maxdist of target pixels (including the target pixels) instead of a distance value

Predeterminado: -1

Tipo de ráster de salida [selection]

Tipo de archivo ráster

Opciones:

  • 0 — Byte
  • 1 — Int16
  • 2 — UInt16
  • 3 — UInt32
  • 4 — Int32
  • 5 — Flotante32

  • 6 — Float64
  • 7 — CInt16
  • 8 — CInt32
  • 9 — CFloat32
  • 10 — CFloat64

Predeterminado: 5

Salidas

Capa de salida [raster]
Raster file in output

Uso de la consola

processing.runalg('gdalogr:proximity', input, values, units, max_dist, nodata, buf_val, rtype, output)

Irregularidad

Descripción

Outputs a single-band raster with values computed from the elevation. Roughness is the degree of irregularity of the surface. It’s calculated by the largest inter-cell difference of a central pixel and its surrounding cell. The determination of the roughness plays a role in the analysis of terrain elevation data, it’s useful for calculations of the river morphology, in climatology and physical geography in general. The algorithm is derived from the GDAL DEM utility .

Parametros

Capa de entrada [raster]
Elevation raster layer.
Numero de banda [number]

The number of a band containing elevation values.

Predeterminado: 1

Clacular bordes [boolean]

Generates edges from the elevation raster.

Predeterminado: False

Salidas

Archivo de salida [raster]
Single-band output raster. The value -9999 is used as the output nodata value.

Uso de la consola

processing.runalg('gdalogr:roughness', input, band, compute_edges, output)

Ver también

Filtrado

Descripción

Removes raster polygons smaller than a provided threshold size (in pixels) and replaces them with the pixel value of the largest neighbour polygon. It is useful if you have a large amount of small areas on your raster map. The algorithm is derived from the GDAL sieve utility .

Parametros

Capa de entrada [raster]

Capa ráster.

Umbral [number]

Only raster polygons smaller than this size will be removed.

Predeterminado: 2

Conexión de píxel [selection]

Either four connectedness or eight connectedness should be used when determining.

Opciones:

  • 0 — 4
  • 1 — 8

Predeterminado: 0

Salidas

Capa de salida [raster]

Capa ráster de salida.

Uso de la consola

processing.runalg('gdalogr:sieve', input, threshold, connections, output)

Ver también

Pendiente

Descripción

Generate a slope map from any GDAL-supported elevation raster. Slope is the angle of inclination to the horizontal. You have the option of specifying the type of slope value you want: degrees or percent slope. The algorithm is derived from the GDAL DEM utility .

Parametros

Capa de entrada [raster]
Elevation raster layer.
Numero de banda [number]

The number of a band containing elevation values.

Predeterminado: 1

Clacular bordes [boolean]

Generates edges from the elevation raster.

Predeterminado: False

Uso Zevenbergen y fórmula Thorne (en lugar de un Horn's) [boolean]

Activates Zevenbergen&Thorne formula for smooth landscapes.

Predeterminado: False

Pendiente expresada como porcentaje (en lugar de grados) [boolean]

You have the option to use slope expressed as degrees.

Predeterminado: False

Escala (ratio de vertical. unidades para horizontal) [number]

The ratio of vertical units to horizontal units.

Por defecto: 1.0

Salidas

Archivo de salida [raster]
32-bit float output raster.

Uso de la consola

processing.runalg('gdalogr:slope', input, band, compute_edges, zevenbergen, as_percent, scale, output)

Ver también

TPI (Índice de Posición Topografico)

Descripción

This command outputs a single-band raster with values computed from the elevation. TPI stands for Topographic Position Index, which is defined as the difference between a central pixel and the mean of its surrounding cells

Parametros

Capa de entrada [raster]
Elevation raster layer
Numero de banda [number]

The number of a band containing elevation values

Predeterminado: 1

Clacular bordes [boolean]

Generates edges from the elevation raster

Predeterminado: False

Salidas

Archivo de salida [raster]
TPI raster in output

Uso de la consola

processing.runalg('gdalogr:tpitopographicpositionindex', input, band, compute_edges, output)

Ver también

GDAL Utilidad DEM

TRI (Índice Robustez del Terreno)

Descripción

This command outputs a single-band raster with values computed from the elevation. TRI stands for Terrain Ruggedness Index, which is defined as the mean difference between a central pixel and its surrounding cells

Parametros

Capa de entrada [raster]
Elevation raster layer
Numero de banda [number]

The number of a band containing elevation values

Predeterminado: 1

Clacular bordes [boolean]

Generates edges from the elevation raster

Predeterminado: False

Salidas

Archivo de salida [raster]

archivo ráster TRI

Uso de la consola

processing.runalg('gdalogr:triterrainruggednessindex', input, band, compute_edges, output)

Ver también

GDAL utilidad DEM