further gdal nodata handling improvements - refs #2023

Conflicts:
	plugins/input/gdal/gdal_featureset.cpp
This commit is contained in:
Dane Springmeyer 2014-01-17 19:13:53 -08:00
parent 55ca9f73ed
commit 77da5d919c
5 changed files with 55 additions and 25 deletions

View file

@ -14,6 +14,12 @@ Released ...
Summary: TODO
- GDAL plugin: Added back support for user driven `nodata` on rgb(a) images (#2023)
- GDAL plugin: Allowed nodata to override alpha band if set on rgba images (#2023)
- GDAL plugin: Added `nodata_tolerance` option to set nearby pixels transparent (has similar effect to the `nearblack` program) (#2023)
- Added support for web fonts: .woff format (#2113)
- Added missing support for `geometry-transform` in `line-pattern` and `polygon-pattern` symbolizers (#2065)

View file

@ -77,7 +77,8 @@ inline GDALDataset* gdal_datasource::open_dataset() const
gdal_datasource::gdal_datasource(parameters const& params)
: datasource(params),
desc_(*params.get<std::string>("type"), "utf-8"),
nodata_value_(params.get<double>("nodata"))
nodata_value_(params.get<double>("nodata")),
nodata_tolerance_(*params.get<double>("nodata_tolerance",1e-12))
{
MAPNIK_LOG_DEBUG(gdal) << "gdal_datasource: Initializing...";
@ -132,16 +133,28 @@ gdal_datasource::gdal_datasource(parameters const& params)
tr[3] = extent_.maxy();
tr[4] = 0;
tr[5] = -extent_.height() / (double)height_;
MAPNIK_LOG_DEBUG(gdal) << "gdal_datasource extent override gives Geotransform="
<< tr[0] << "," << tr[1] << ","
<< tr[2] << "," << tr[3] << ","
<< tr[4] << "," << tr[5];
}
else
{
dataset->GetGeoTransform(tr);
if (dataset->GetGeoTransform(tr) != CPLE_None)
{
MAPNIK_LOG_DEBUG(gdal) << "gdal_datasource GetGeotransform failure gives="
<< tr[0] << "," << tr[1] << ","
<< tr[2] << "," << tr[3] << ","
<< tr[4] << "," << tr[5];
}
else
{
MAPNIK_LOG_DEBUG(gdal) << "gdal_datasource Geotransform="
<< tr[0] << "," << tr[1] << ","
<< tr[2] << "," << tr[3] << ","
<< tr[4] << "," << tr[5];
}
}
// TODO - We should throw for true non-north up images, but the check
// below is clearly too restrictive.
@ -228,7 +241,8 @@ featureset_ptr gdal_datasource::features(query const& q) const
nbands_,
dx_,
dy_,
nodata_value_));
nodata_value_,
nodata_tolerance_));
}
featureset_ptr gdal_datasource::features_at_point(coord2d const& pt, double tol) const
@ -249,5 +263,6 @@ featureset_ptr gdal_datasource::features_at_point(coord2d const& pt, double tol)
nbands_,
dx_,
dy_,
nodata_value_));
nodata_value_,
nodata_tolerance_));
}

View file

@ -67,6 +67,7 @@ private:
int nbands_;
bool shared_dataset_;
boost::optional<double> nodata_value_;
double nodata_tolerance_;
};
#endif // GDAL_DATASOURCE_HPP

View file

@ -34,6 +34,7 @@
#include <boost/variant/apply_visitor.hpp>
// stl
#include <cmath>
#include <memory>
#include "gdal_featureset.hpp"
#include <gdal_priv.h>
@ -60,7 +61,8 @@ gdal_featureset::gdal_featureset(GDALDataset& dataset,
int nbands,
double dx,
double dy,
boost::optional<double> const& nodata)
boost::optional<double> const& nodata,
double nodata_tolerance)
: dataset_(dataset),
ctx_(std::make_shared<mapnik::context_type>()),
band_(band),
@ -72,6 +74,7 @@ gdal_featureset::gdal_featureset(GDALDataset& dataset,
dy_(dy),
nbands_(nbands),
nodata_value_(nodata),
nodata_tolerance_(nodata_tolerance),
first_(true)
{
ctx_->push("nodata");
@ -185,9 +188,9 @@ feature_ptr gdal_featureset::get_feature(mapnik::query const& q)
int im_width = int(width_res * intersect.width() + 0.5);
int im_height = int(height_res * intersect.height() + 0.5);
double sym_downsample_factor = q.get_filter_factor();
im_width = int(im_width * sym_downsample_factor + 0.5);
im_height = int(im_height * sym_downsample_factor + 0.5);
double filter_factor = q.get_filter_factor();
im_width = int(im_width * filter_factor + 0.5);
im_height = int(im_height * filter_factor + 0.5);
// case where we need to avoid upsampling so that the
// image can be later scaled within raster_symbolizer
@ -287,13 +290,13 @@ feature_ptr gdal_featureset::get_feature(mapnik::query const& q)
MAPNIK_LOG_DEBUG(gdal) << "gdal_featureset: Processing rgb bands...";
raster_nodata = red->GetNoDataValue(&raster_has_nodata);
GDALColorTable *color_table = red->GetColorTable();
if (!alpha && raster_has_nodata && !color_table)
bool has_nodata = nodata_value_ || raster_has_nodata;
if (has_nodata && !color_table)
{
double apply_nodata = nodata_value_ ? *nodata_value_ : raster_nodata;
// read the data in and create an alpha channel from the nodata values
// NOTE: we intentionally ignore user supplied nodata value since it only
// works for grayscale images or a single band (as a double)
// TODO - we assume here the nodata value for the red band applies to all band
// but that may not always be the case: http://trac.osgeo.org/gdal/ticket/2734
// TODO - we assume here the nodata value for the red band applies to all bands
// more details about this at http://trac.osgeo.org/gdal/ticket/2734
float* imageData = (float*)image.getBytes();
red->RasterIO(GF_Read, x_off, y_off, width, height,
imageData, image.width(), image.height(),
@ -301,7 +304,7 @@ feature_ptr gdal_featureset::get_feature(mapnik::query const& q)
int len = image.width() * image.height();
for (int i = 0; i < len; ++i)
{
if (std::fabs(raster_nodata - imageData[i]) < 1e-12)
if (std::fabs(apply_nodata - imageData[i]) < nodata_tolerance_)
{
*reinterpret_cast<unsigned *>(&imageData[i]) = 0;
}
@ -336,7 +339,7 @@ feature_ptr gdal_featureset::get_feature(mapnik::query const& q)
int len = image.width() * image.height();
for (int i = 0; i < len; ++i)
{
if (std::fabs(apply_nodata - imageData[i]) < 1e-12)
if (std::fabs(apply_nodata - imageData[i]) < nodata_tolerance_)
{
*reinterpret_cast<unsigned *>(&imageData[i]) = 0;
}
@ -380,13 +383,16 @@ feature_ptr gdal_featureset::get_feature(mapnik::query const& q)
if (alpha)
{
MAPNIK_LOG_DEBUG(gdal) << "gdal_featureset: processing alpha band...";
if (raster_has_nodata)
if (!raster_has_nodata)
{
MAPNIK_LOG_ERROR(gdal) << "warning: alpha channel being used instead of nodata value";
}
alpha->RasterIO(GF_Read, x_off, y_off, width, height, image.getBytes() + 3,
image.width(), image.height(), GDT_Byte, 4, 4 * image.width());
}
else
{
MAPNIK_LOG_ERROR(gdal) << "warning: nodata value (" << raster_nodata << ") used to set transparency instead of alpha band";
}
}
}
// set nodata value to be used in raster colorizer
if (nodata_value_)

View file

@ -67,7 +67,8 @@ public:
int nbands,
double dx,
double dy,
boost::optional<double> const& nodata);
boost::optional<double> const& nodata,
double nodata_tolerance);
virtual ~gdal_featureset();
mapnik::feature_ptr next();
@ -90,6 +91,7 @@ private:
double dy_;
int nbands_;
boost::optional<double> nodata_value_;
double nodata_tolerance_;
bool first_;
};