DOC: enhance documentation of FineRegistration

Modules/Applications/AppStereo/app/otbFineRegistration.cxx

@@ -120,7 +120,16 @@ private:
     SetDescription("Estimate disparity map between two images.");
 
     SetDocName("Fine Registration");
-    SetDocLongDescription("Estimate disparity map between two images. Output image contain x offset, y offset and metric value.");
+    SetDocLongDescription("This application computes a disparity map between "
+      "two images that correspond to the same scene. It is intended for case "
+      "where small misregistration between images should be estimated and fixed"
+      ". The search is performed in 2D.\n\n"
+      "The algorithm uses an iterative approach to estimate a best match "
+      "between local patches. The typical use case is registration betwween "
+      "similar bands, or between two acquisitions. The output image contains "
+      "X and Y offsets, as well as the metric value. A sub-pixel accuracy can "
+      "be expected. The input images should have the same size and same "
+      "physical space.");
     SetDocLimitations("None");
     SetDocAuthors("OTB-Team");
     SetDocSeeAlso(" ");
@@ -134,7 +143,9 @@ private:
     SetParameterDescription( "sec", "The secondary image." );
 
     AddParameter(ParameterType_OutputImage,  "out",   "Output Image");
-    SetParameterDescription( "out", "The output image." );
+    SetParameterDescription( "out", "The output image contains 3 bands, for X "
+      "offset, Y offset and the metric value. It may contain a 4th one with the"
+      " validity mask (if used)." );
 
     AddParameter(ParameterType_Int,  "erx",   "Exploration Radius X");
     SetParameterDescription( "erx", "The exploration radius along x (in pixels)" );
@@ -145,15 +156,18 @@ private:
     SetMinimumParameterIntValue("ery", 0);
 
     AddParameter(ParameterType_Int,  "mrx",   "Metric Radius X");
-    SetParameterDescription( "mrx", "Radius along x (in pixels) of the metric computation window" );
+    SetParameterDescription( "mrx", "Radius along x (in pixels) of the metric "
+      "computation window" );
     SetMinimumParameterIntValue("mrx", 0);
 
     AddParameter(ParameterType_Int,  "mry",   "Metric Radius Y");
-    SetParameterDescription( "mry", "Radius along y (in pixels) of the metric computation window" );
+    SetParameterDescription( "mry", "Radius along y (in pixels) of the metric "
+      "computation window" );
     SetMinimumParameterIntValue("mry", 0);
 
     AddParameter(ParameterType_InputImage,  "w",   "Image To Warp");
-    SetParameterDescription( "w", "The image to warp after disparity estimation is completed" );
+    SetParameterDescription( "w", "The image to warp after disparity estimation"
+    " is completed." );
     MandatoryOff("w");
 
     AddParameter(ParameterType_OutputImage,  "wo",   "Output Warped Image");
@@ -161,65 +175,81 @@ private:
     MandatoryOff("wo");
 
     AddParameter(ParameterType_Float,  "cox",   "Coarse Offset X");
-    SetParameterDescription( "cox", "Coarse offset along x (in physical space) between the two images" );
+    SetParameterDescription( "cox", "Coarse offset along x (in physical space)"
+      " between the two images, used as an initial offset for all pixels." );
     SetDefaultParameterFloat("cox", 0.0);
     MandatoryOff("cox");
 
     AddParameter(ParameterType_Float,  "coy",   "Coarse Offset Y");
-    SetParameterDescription( "coy", "Coarse offset along y (in physical space) between the two images" );
+    SetParameterDescription( "coy", "Coarse offset along y (in physical space)"
+      " between the two images, used as an initial offset for all pixels." );
     SetDefaultParameterFloat("coy", 0.0);
     MandatoryOff("coy");
 
     AddParameter(ParameterType_Float,  "ssrx",   "Sub-Sampling Rate X");
-    SetParameterDescription( "ssrx", "Generates a result at a coarser resolution with a given sub-sampling rate along X" );
+    SetParameterDescription( "ssrx", "Generates a result at a coarser "
+      "resolution with a given sub-sampling rate along X" );
     SetDefaultParameterFloat("ssrx", 1.0);
     SetMinimumParameterFloatValue("ssrx", 1.0);
     MandatoryOff("ssrx");
 
     AddParameter(ParameterType_Float,  "ssry",   "Sub-Sampling Rate Y");
-    SetParameterDescription( "ssry", "Generates a result at a coarser resolution with a given sub-sampling rate along Y" );
+    SetParameterDescription( "ssry", "Generates a result at a coarser "
+      "resolution with a given sub-sampling rate along Y" );
     SetDefaultParameterFloat("ssry", 1.0);
     SetMinimumParameterFloatValue("ssry", 1.0);
     MandatoryOff("ssry");
 
     AddParameter(ParameterType_Float,  "rgsx",   "Reference Gaussian Smoothing X");
-    SetParameterDescription( "rgsx", "Performs a gaussian smoothing of the reference image. Parameter is gaussian sigma (in pixels) in X direction." );
+    SetParameterDescription( "rgsx", "Performs a gaussian smoothing of the "
+      "reference image. Parameter is gaussian sigma (in pixels) in X direction." );
     MandatoryOff("rgsx");
 
     AddParameter(ParameterType_Float,  "rgsy",   "Reference Gaussian Smoothing Y");
-    SetParameterDescription( "rgsy", "Performs a gaussian smoothing of the reference image. Parameter is gaussian sigma (in pixels) in Y direction." );
+    SetParameterDescription( "rgsy", "Performs a gaussian smoothing of the "
+      "reference image. Parameter is gaussian sigma (in pixels) in Y direction." );
     MandatoryOff("rgsy");
 
     AddParameter(ParameterType_Float,  "sgsx",   "Secondary Gaussian Smoothing X");
-    SetParameterDescription( "sgsx", "Performs a gaussian smoothing of the secondary image. Parameter is gaussian sigma (in pixels) in X direction." );
+    SetParameterDescription( "sgsx", "Performs a gaussian smoothing of the "
+      "secondary image. Parameter is gaussian sigma (in pixels) in X direction." );
     MandatoryOff("sgsx");
 
     AddParameter(ParameterType_Float,  "sgsy",   "Secondary Gaussian Smoothing Y");
-    SetParameterDescription( "sgsy", "Performs a gaussian smoothing of the secondary image. Parameter is gaussian sigma (in pixels) in Y direction." );
+    SetParameterDescription( "sgsy", "Performs a gaussian smoothing of the "
+      "secondary image. Parameter is gaussian sigma (in pixels) in Y direction." );
     MandatoryOff("sgsy");
 
     AddParameter(ParameterType_String,  "m",   "Metric");
-    SetParameterDescription( "m", "Choose the metric used for block matching. Available metrics are cross-correlation (CC), cross-correlation with subtracted mean (CCSM), mean-square difference (MSD), mean reciprocal square difference (MRSD) and mutual information (MI). Default is cross-correlation" );
+    SetParameterDescription( "m", "Choose the metric used for block matching. "
+      "Available metrics are cross-correlation (CC), cross-correlation with "
+      "subtracted mean (CCSM), mean-square difference (MSD), mean reciprocal "
+      "square difference (MRSD) and mutual information (MI). Default is "
+      "cross-correlation" );
     MandatoryOff("m");
 
     AddParameter(ParameterType_Float,  "spa",   "SubPixelAccuracy");
-    SetParameterDescription( "spa", "Metric extrema location will be refined up to the given accuracy. Default is 0.01" );
+    SetParameterDescription( "spa", "Metric extrema location will be refined up"
+      " to the given accuracy. Default is 0.01" );
     SetDefaultParameterFloat("spa", 0.01);
     SetMinimumParameterFloatValue("spa", 0.0);
     MandatoryOff("spa");
 
     AddParameter(ParameterType_Float,  "cva",   "ConvergenceAccuracy");
-    SetParameterDescription( "cva", "Metric extrema will be refined up to the given accuracy. Default is 0.01" );
+    SetParameterDescription( "cva", "Metric extrema will be refined up to the"
+      " given accuracy. Default is 0.01" );
     SetDefaultParameterFloat("cva", 0.01);
     SetMinimumParameterFloatValue("cva", 0.0);
     MandatoryOff("cva");
 
     AddParameter(ParameterType_Float,  "vmlt",   "Validity Mask Lower Threshold");
-    SetParameterDescription( "vmlt", "Lower threshold to obtain a validity mask." );
+    SetParameterDescription( "vmlt", "Lower threshold to compute the validity "
+      "mask. This mask will be the 4th output band." );
     MandatoryOff("vmlt");
 
     AddParameter(ParameterType_Float,  "vmut",   "Validity Mask Upper Threshold");
-    SetParameterDescription( "vmut", "Upper threshold to obtain a validity mask." );
+    SetParameterDescription( "vmut", "Upper threshold to obtain a validity "
+      "mask. This mask will be the 4th output band." );
     MandatoryOff("vmut");
 
     AddRAMParameter();