Files
OpenSceneGraph/src/osgPlugins/pnm/ReaderWriterPNM.cpp
2009-01-09 12:17:40 +00:00

494 lines
15 KiB
C++

// PNM Reader -- Written by Eric Sokolowsky
// Reads Ascii and Binary files in the PPM, PGM, and PBM formats.
#include <osg/Image>
#include <osg/Notify>
#include <osg/Endian>
#include <osgDB/Registry>
#include <osgDB/FileNameUtils>
#include <osgDB/FileUtils>
#include <osgDB/fstream>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
using namespace osg;
template <class T>
unsigned char* read_bitmap_ascii(FILE* fp, int width, int height)
{
T* data = new T[width*height];
T* dst = data;
T* end = data + width*height;
while(dst < end)
{
T value = 0;
// read in characters looking for '0's and '1's, these
// values map to 255 and 0. Any other characters
// are silently ignored.
while(1)
{
int ch = fgetc(fp);
if (feof(fp) || ferror(fp))
{
delete [] data;
return NULL;
}
if (ch == '0')
{
value = 255;
break;
}
else if (ch == '1')
{
value = 0;
break;
}
}
// place value in the image
*(dst++) = value;
}
return reinterpret_cast<unsigned char*>(data);
}
template <class T>
unsigned char* read_grayscale_ascii(FILE* fp, int width, int height)
{
T* data = new T[width*height];
T* dst = data;
T* end = data + width*height;
while(dst < end)
{
int ch;
T value = 0;
// read and discard any whitespace
// until a digit is reached
do
{
ch = fgetc(fp);
if (feof(fp) || ferror(fp))
{
delete [] data;
return NULL;
}
}
while(!isdigit(ch));
// continue reading digits and incrementally
// construct the integer value
do
{
value = 10*value + (ch - '0');
ch = fgetc(fp);
if (feof(fp) || ferror(fp))
{
delete [] data;
return NULL;
}
}
while(isdigit(ch));
// place value in the image
*(dst++) = value;
}
return reinterpret_cast<unsigned char*>(data);
}
template <class T>
unsigned char* read_color_ascii(FILE* fp, int width, int height)
{
T* data = new T[3*width*height];
T* dst = data;
T* end = data + 3*width*height;
osg::notify(osg::NOTICE)<<"Width = "<<width<<std::endl;
osg::notify(osg::NOTICE)<<"Height = "<<height<<std::endl;
unsigned int numRead = 0;
while(dst < end)
{
int ch;
T value = 0;
// read and discard any whitespace
// until a digit is reached
do
{
ch = fgetc(fp);
if (feof(fp) || ferror(fp))
{
osg::notify(osg::NOTICE)<<"Error 1 "<<numRead<<std::endl;
delete [] data;
return NULL;
}
}
while(!isdigit(ch));
// continue reading digits and incrementally
// construct the integer value
do
{
value = 10*value + (ch - '0');
ch = fgetc(fp);
if (feof(fp) || ferror(fp))
{
osg::notify(osg::NOTICE)<<"Error 2"<<std::endl;
delete [] data;
return NULL;
}
}
while(isdigit(ch));
++numRead;
// place value in the image
*(dst++) = value;
}
osg::notify(osg::NOTICE)<<"Completed"<<std::endl;
return reinterpret_cast<unsigned char*>(data);
}
template <class T>
unsigned char* read_bitmap_binary(FILE* fp, int width, int height)
{
T* data = new T[width*height];
for(int y = 0; y < height; y++)
{
T* dst = data + (y+0)*width;
T* end = data + (y+1)*width;
while(dst < end)
{
unsigned char b = fgetc(fp);
if (feof(fp) || ferror(fp))
{
fclose(fp);
delete [] data;
return NULL;
}
for(int i = 7; i >= 0 && dst < end; i--)
{
// 1 means black, 0 means white
T data_value = (b & (1<<i)) ? 0 : 255;
*(dst++) = data_value;
}
}
}
return reinterpret_cast<unsigned char*>(data);
}
template <class T>
unsigned char* read_grayscale_binary(FILE* fp, int width, int height)
{
T* data = new T[width*height];
if (fread(data, sizeof(T)*width*height, 1, fp) != 1)
{
fclose(fp);
delete [] data;
return NULL;
}
// if the machine is little endian swap the bytes around
if (sizeof(T) > 1 && getCpuByteOrder() == osg::LittleEndian)
{
for(int i = 0; i < width*height; i++)
{
unsigned char* bs = (unsigned char*)(&data[i]);
std::swap(bs[0], bs[1]);
}
}
return reinterpret_cast<unsigned char*>(data);
}
template <class T>
unsigned char* read_color_binary(FILE* fp, int width, int height)
{
T* data = new T[3*width*height];
if (fread(data, 3*sizeof(T)*width*height, 1, fp) != 1)
{
fclose(fp);
delete [] data;
return NULL;
}
// if the machine is little endian swap the bytes around
if (sizeof(T) > 1 && getCpuByteOrder() == osg::LittleEndian)
{
for(int i = 0; i < 3*width*height; i++)
{
unsigned char* bs = (unsigned char*)(&data[i]);
std::swap(bs[0], bs[1]);
}
}
return reinterpret_cast<unsigned char*>(data);
}
class ReaderWriterPNM : public osgDB::ReaderWriter
{
public:
ReaderWriterPNM()
{
supportsExtension("pnm","PNM Image format");
supportsExtension("ppm","PNM Image format");
supportsExtension("pgm","PNM Image format");
supportsExtension("pbm","PNM Image format");
}
virtual const char* className() const { return "PNM Image Reader/Writer"; }
virtual ReadResult readImage(const std::string& file, const osgDB::ReaderWriter::Options* options) const
{
std::string ext = osgDB::getLowerCaseFileExtension(file);
if (!acceptsExtension(ext)) return ReadResult::FILE_NOT_HANDLED;
std::string fileName = osgDB::findDataFile( file, options );
if (fileName.empty()) return ReadResult::FILE_NOT_FOUND;
FILE *fp = NULL;
char line[300];
int ppmtype = 0; /* P1, P2, etc. */
int width = 0;
int height = 0;
int max_value = 0;
// Open file.
fp = osgDB::fopen(fileName.c_str(), "rb");
// Read header items.
int row;
for (row = 1; row <= 3; row++)
{
if ( fgets(line, 300, fp) == NULL)
break;
char *cp = line;
while (*cp && isspace(*cp))
cp++;
if (! *cp || *cp == '#')
{
// Skip comment lines.
row--;
}
else if (row == 1)
{
// Get the image type.
if (line[0] == 'p' || line[0] == 'P')
{
ppmtype = line[1] - '0';
}
}
else if (row == 2)
{
// Get the image size.
width = atoi(line);
char *cp = line + strspn(line, "\t \n\r");
cp += strspn(cp, "0123456789");
cp += strspn(line, "\t \n\r");
height = atoi(cp);
// pbm files don't have row 3
if (ppmtype == 1 || ppmtype == 4)
{
max_value = 1;
break;
}
}
else if (row == 3)
{
// Get the maximum value
max_value = atoi(line);
}
}
// Check for valid values.
if (width <= 0 || height <= 0 ||
max_value <= 0 || max_value > 65535 ||
ppmtype < 1 || ppmtype > 6)
{
fclose(fp);
return ReadResult::ERROR_IN_READING_FILE;
}
int pixelFormat = 0;
int dataType = 0;
unsigned char* data = NULL;
if (max_value > 255)
{
dataType = GL_UNSIGNED_SHORT;
switch(ppmtype)
{
case 1: // bitmap ascii
pixelFormat = GL_LUMINANCE;
data = read_bitmap_ascii<unsigned short>(fp, width, height);
break;
case 2: // grayscale ascii
pixelFormat = GL_LUMINANCE;
data = read_grayscale_ascii<unsigned short>(fp, width, height);
break;
case 3: // color ascii
pixelFormat = GL_RGB;
data = read_color_ascii<unsigned short>(fp, width, height);
break;
case 4: // bitmap binary
pixelFormat = GL_LUMINANCE;
data = read_bitmap_binary<unsigned short>(fp, width, height);
break;
case 5: // grayscale binary
pixelFormat = GL_LUMINANCE;
data = read_grayscale_binary<unsigned short>(fp, width, height);
break;
case 6: // color binary
pixelFormat = GL_RGB;
data = read_color_binary<unsigned short>(fp, width, height);
break;
}
}
else
{
dataType = GL_UNSIGNED_BYTE;
switch(ppmtype)
{
case 1: // bitmap ascii
pixelFormat = GL_LUMINANCE;
data = read_bitmap_ascii<unsigned char>(fp, width, height);
break;
case 2: // grayscale ascii
pixelFormat = GL_LUMINANCE;
data = read_grayscale_ascii<unsigned char>(fp, width, height);
break;
case 3: // color ascii
pixelFormat = GL_RGB;
data = read_color_ascii<unsigned char>(fp, width, height);
break;
case 4: // bitmap binary
pixelFormat = GL_LUMINANCE;
data = read_bitmap_binary<unsigned char>(fp, width, height);
break;
case 5: // grayscale binary
pixelFormat = GL_LUMINANCE;
data = read_grayscale_binary<unsigned char>(fp, width, height);
break;
case 6: // color binary
pixelFormat = GL_RGB;
data = read_color_binary<unsigned char>(fp, width, height);
break;
}
}
if (data == NULL)
{
if (fp)
fclose(fp);
return ReadResult::FILE_NOT_HANDLED;
}
if (fp)
fclose(fp);
osg::Image* pOsgImage = new osg::Image();
pOsgImage->setFileName(fileName.c_str());
pOsgImage->setImage(width, height, 1,
pixelFormat,
pixelFormat,
dataType,
data,
osg::Image::USE_NEW_DELETE);
if (options && options->getOptionString().find("flip")!=std::string::npos)
{
pOsgImage->flipVertical();
}
return pOsgImage;
}
virtual WriteResult writeImage(const osg::Image& image,std::ostream& fout,const osgDB::ReaderWriter::Options* options) const
{
bool ascii = (options && options->getOptionString().find("ascii")!=std::string::npos);
if (ascii)
{
// ascii ppm format.
fout<<"P3"<<std::endl;
fout<<image.s()<<" "<<image.t()<<std::endl;
fout<<"255"<<std::endl;
for(int row = image.t()-1; row >= 0; --row)
{
const unsigned char* ptr = image.data(0,row);
for(int col = 0; col < image.s(); ++col)
{
fout<<static_cast<int>(*(ptr++));
fout<<" "<<static_cast<int>(*(ptr++));
fout<<" "<<static_cast<int>(*(ptr++))<<" ";
}
fout<<std::endl;
}
}
else
{
// binary ppm format
fout<<"P6"<<std::endl;
fout<<image.s()<<" "<<image.t()<<std::endl;
fout<<"255"<<std::endl;
for(int row = image.t()-1; row >= 0; --row)
{
const unsigned char* ptr = image.data(0,row);
for(int col = 0; col < image.s(); ++col)
{
fout.put(*(ptr++));
fout.put(*(ptr++));
fout.put(*(ptr++));
}
}
}
return WriteResult::FILE_SAVED;
}
virtual WriteResult writeImage(const osg::Image& image,const std::string& fileName, const osgDB::ReaderWriter::Options* options) const
{
// Only ppm format output supported
std::string ext = osgDB::getFileExtension(fileName);
if ( !osgDB::equalCaseInsensitive(ext, "ppm") ) return WriteResult::FILE_NOT_HANDLED;
// only support rgb images right now.
if (image.getPixelFormat()!=GL_RGB || image.getDataType()!=GL_UNSIGNED_BYTE) return WriteResult("Error image pixel format not supported by pnm writer.");
osgDB::ofstream fout(fileName.c_str(), std::ios::out | std::ios::binary);
if(!fout) return WriteResult::ERROR_IN_WRITING_FILE;
return writeImage(image,fout,options);
}
};
// now register with Registry to instantiate the above
// reader/writer.
REGISTER_OSGPLUGIN(pnm, ReaderWriterPNM)