DynamicConvert - Dynamic Conversion¶

Change the pixel type and rescale the image’s dynamic

Detailed description¶

This application performs an image pixel type conversion (short, ushort, uchar, int, uint, float and double types are handled). The output image is written in the specified format (ie. that corresponds to the given extension).: The conversion can include a rescale of the data range, by default it’s set between the 2nd to the 98th percentile. The rescale can be linear or log2. The choice of the output channels can be done with the extended filename, but less easy to handle. To do this, a ‘channels’ parameter allows you to select the desired bands at the output. There are 3 modes, the available choices are: * grayscale : to display mono image as standard color image * rgb : select 3 bands in the input image (multi-bands) * all : keep all bands.

Parameters¶

This section describes in details the parameters available for this application. Table [1] presents a summary of these parameters and the parameters keys to be used in command-line and programming languages. Application key is DynamicConvert .

[1]	Table: Parameters table for Dynamic Conversion.

Parameter Key	Parameter Name	Parameter Type
in	Input image	Input image
out	Output Image	Output image
type	Rescale type	Choices
type linear	Linear	Choice
type log2	Log2	Choice
type.linear.gamma	Gamma correction factor	Float
mask	Input mask	Input image
quantile	Histogram quantile cutting	Group
quantile.high	High cut quantile	Float
quantile.low	Low cut quantile	Float
channels	Channels selection	Choices
channels all	Default mode	Choice
channels grayscale	Grayscale mode	Choice
channels rgb	RGB composition	Choice
channels.grayscale.channel	Grayscale channel	Int
channels.rgb.red	Red Channel	Int
channels.rgb.green	Green Channel	Int
channels.rgb.blue	Blue Channel	Int
outmin	Output min value	Float
outmax	Output max value	Float
ram	Available RAM (Mb)	Int
inxml	Load otb application from xml file	XML input parameters file
outxml	Save otb application to xml file	XML output parameters file

Input image: Input image.

Output Image: Output image.

Rescale type: Transfer function for the rescaling. Available choices are:

Linear

Gamma correction factor: Gamma correction factor.

Log2

Input mask: Optional mask to indicate which pixels are valid for computing the histogram quantiles. Pixels where the mask is zero will not contribute to the histogram. The mask must have the same dimensions as the input image.

[Histogram quantile cutting]: Cut the histogram edges before rescaling.

High cut quantile: Quantiles to cut from histogram high values before computing min/max rescaling (in percent, 2 by default).
Low cut quantile: Quantiles to cut from histogram low values before computing min/max rescaling (in percent, 2 by default).

Channels selection: It’s possible to select the channels of the output image. There are 3 modes, the available choices are:. Available choices are:

Default mode: Select all bands in the input image, (1,...,n).
Grayscale mode: Display single channel as standard color image.

Grayscale channel

RGB composition: Select 3 bands in the input image (multi-bands), by default (1,2,3).

Red Channel: Red channel index.

Green Channel: Green channel index.

Blue Channel: Blue channel index.

Output min value: Minimum value of the output image.

Output max value: Maximum value of the output image.

Available RAM (Mb): Available memory for processing (in MB).

Load otb application from xml file: Load otb application from xml file.

Save otb application to xml file: Save otb application to xml file.

Example¶

To run this example in command-line, use the following:

otbcli_DynamicConvert -in QB_Toulouse_Ortho_XS.tif -out otbConvertWithScalingOutput.png -type linear -channels rgb -outmin 0 -outmax 255

To run this example from Python, use the following code snippet:

#!/usr/bin/python

# Import the otb applications package
import otbApplication

# The following line creates an instance of the DynamicConvert application
DynamicConvert = otbApplication.Registry.CreateApplication("DynamicConvert")

# The following lines set all the application parameters:
DynamicConvert.SetParameterString("in", "QB_Toulouse_Ortho_XS.tif")

DynamicConvert.SetParameterString("out", "otbConvertWithScalingOutput.png")

DynamicConvert.SetParameterString("type","linear")

DynamicConvert.SetParameterString("channels","rgb")

DynamicConvert.SetParameterFloat("outmin", 0)

DynamicConvert.SetParameterFloat("outmax", 255)

# The following line execute the application
DynamicConvert.ExecuteAndWriteOutput()

Limitations¶

None

Authors¶

This application has been written by OTB-Team.