/**
A unified header reading routine for .bin and .fits files. It read the array
information and string header if any. Return non zero value if reading failed*/
int read_header2(header_t *header, file_t *fp) {
int ans;
header->str=NULL;
if(fp->isfits) {
ans=read_fits_header(header, fp);
} else {
ans=read_bin_header(header, fp);
}
return ans;
}
bool
FitsInput::set_spec_info ()
{
keys.clear ();
// FITS spec doesn't say anything about color space or
// number of channels, so we read all images as if they
// all were one-channel images
m_spec = ImageSpec(0, 0, 1, TypeDesc::UNKNOWN);
// reading info about current subimage
if (! read_fits_header ())
return false;
// we don't deal with one dimension images
// it's some kind of spectral data
if (! m_spec.width || ! m_spec.height) {
m_spec.width = m_spec.full_width = 0;
m_spec.height = m_spec.full_height = 0;
}
// now we can get the current position in the file
// this is the start of the image data
// we will need it in the read_native_scanline method
fgetpos(m_fd, &m_filepos);
if (m_bitpix == 8)
m_spec.set_format (TypeDesc::UCHAR);
else if (m_bitpix == 16)
m_spec.set_format (TypeDesc::USHORT);
else if (m_bitpix == 32)
m_spec.set_format (TypeDesc::UINT);
else if (m_bitpix == -32)
m_spec.set_format (TypeDesc::FLOAT);
else if (m_bitpix == -64)
m_spec.set_format (TypeDesc::DOUBLE);
return true;
}
bool
FitsInput::read_fits_header (void)
{
std::string fits_header (HEADER_SIZE, 0);
// we read whole header at once
if (fread (&fits_header[0], 1, HEADER_SIZE, m_fd) != HEADER_SIZE) {
if (feof (m_fd))
error ("Hit end of file unexpectedly");
else
error ("read error");
return false; // Read failed
}
for (int i = 0; i < CARDS_PER_HEADER; ++i) {
std::string card (CARD_SIZE, 0);
// reading card number i
memcpy (&card[0], &fits_header[i*CARD_SIZE], CARD_SIZE);
std::string keyname, value;
fits_pvt::unpack_card (card, keyname, value);
// END means that this is end of the FITS header
// we can now add to the ImageSpec COMMENT, HISTORY and HIERARCH keys
if (keyname == "END") {
// removing white spaces that we use to separate lines of comments
// from the end ot the string
m_comment = m_comment.substr (0, m_comment.size() - m_sep.size ());
m_history = m_history.substr (0, m_history.size() - m_sep.size ());
m_hierarch = m_hierarch.substr (0, m_hierarch.size() - m_sep.size ());
add_to_spec ("Comment", m_comment);
add_to_spec ("History", m_history);
add_to_spec ("Hierarch", m_hierarch);
return true;
}
if (keyname == "SIMPLE" || keyname == "XTENSION")
continue;
// setting up some important fields
// m_bitpix - format of the data (eg. bpp)
// m_naxes - number of axes
// width, height and depth of the image
if (keyname == "BITPIX") {
m_bitpix = atoi (&card[10]);
continue;
}
if (keyname == "NAXIS") {
m_naxes = atoi (&card[10]);
continue;
}
if (keyname == "NAXIS1") {
m_spec.width = atoi (&card[10]);
m_spec.full_width = m_spec.width;
continue;
}
if (keyname == "NAXIS2") {
m_spec.height = atoi (&card[10]);
m_spec.full_height = m_spec.height;
continue;
}
// ignoring other axis
if (keyname.substr (0,5) == "NAXIS") {
continue;
}
if (keyname == "ORIENTAT") {
add_to_spec ("Orientation", value);
continue;
}
if (keyname == "DATE") {
add_to_spec ("DateTime", convert_date (value));
continue;
}
if (keyname == "COMMENT") {
m_comment += (value + m_sep);
continue;
}
if (keyname == "HISTORY") {
m_history += (value + m_sep);
continue;
}
if (keyname == "HIERARCH") {
m_hierarch += (value + m_sep);
continue;
}
add_to_spec (pystring::capitalize(keyname), value);
}
// if we didn't found END keyword in current header, we read next one
return read_fits_header ();
}
