static Bool
load( PImgCodec instance, PImgLoadFileInstance fi)
{
dPROFILE;
LoadRec * l = ( LoadRec *) fi-> instance;
png_uint_32 width, height;
int obd, bit_depth, color_type, interlace_type, bpp, number_passes, pass, filter;
HV * profile;
Color background;
int alpha_opt, channels, trns_n;
Bool icon;
Handle alpha_image;
png_bytep trns_t;
png_color_16p trns_p;
if (setjmp(png_jmpbuf( l-> png_ptr)) != 0) return false;
profile = fi-> profile;
png_read_info(l->png_ptr, l->info_ptr);
png_get_IHDR(l->png_ptr, l->info_ptr, &width, &height, &bit_depth, &color_type,
&interlace_type, NULL, &filter);
obd = bit_depth;
channels = (int) png_get_channels(l->png_ptr, l->info_ptr);
icon = kind_of( fi-> object, CIcon);
switch ( bit_depth) {
case 1: case 4: case 8:
break;
case 2:
png_set_packing(l->png_ptr);
bit_depth = 4;
break;
case 16:
png_set_strip_16(l->png_ptr);
bit_depth = 8;
break;
default:
sprintf( fi-> errbuf, "Bit depth %d is not supported", bit_depth);
return false;
}
switch ( color_type) {
case PNG_COLOR_TYPE_GRAY:
bpp = bit_depth | imGrayScale;
break;
case PNG_COLOR_TYPE_PALETTE:
bpp = bit_depth;
break;
case PNG_COLOR_TYPE_RGB:
png_set_bgr(l-> png_ptr);
bpp = 24;
break;
case PNG_COLOR_TYPE_GRAY_ALPHA:
bpp = bit_depth | imGrayScale;
break;
case PNG_COLOR_TYPE_RGB_ALPHA:
png_set_bgr(l-> png_ptr);
bpp = 24;
break;
default:
sprintf( fi-> errbuf, "Unknown file color type: %d", color_type);
return false;
}
/* gamma stuff */
{
double screen_gamma = default_screen_gamma, gamma = 0.45455;
Bool has_gamma = false;
if ( pexist( screen_gamma)) {
screen_gamma = pget_f( screen_gamma);
if ( screen_gamma < PNG_GAMMA_THRESHOLD || screen_gamma > PNG_MAX_GAMMA) {
sprintf( fi-> errbuf, "Error: screen_gamma value must be within %g..%g", PNG_GAMMA_THRESHOLD, (double)PNG_MAX_GAMMA);
return false;
}
}
#ifdef PNG_gAMA_SUPPORTED
if ( pexist( gamma)) {
gamma = pget_f( gamma);
if ( gamma < PNG_GAMMA_THRESHOLD || gamma > PNG_MAX_GAMMA) {
sprintf( fi-> errbuf, "Error: gamma value must be within %g..%g", PNG_GAMMA_THRESHOLD, (double)PNG_MAX_GAMMA);
return false;
}
has_gamma = true;
} else if ( png_get_gAMA(l-> png_ptr, l-> info_ptr, &gamma)) {
has_gamma = true;
}
#endif
if ( has_gamma) png_set_gamma(l->png_ptr, screen_gamma, gamma);
}
/* alpha option */
if ( pexist( alpha)) {
char * c = pget_c( alpha);
if ( stricmp( c, "blend") == 0) alpha_opt = ALPHA_OPT_BLEND; else
if ( stricmp( c, "split") == 0) {
if ( icon)
outc("Alpha channel cannot be loaded to an Icon object")
else
alpha_opt = ALPHA_OPT_SPLIT;
} else
if ( stricmp( c, "none") == 0) alpha_opt = ALPHA_OPT_NONE; else {
snprintf( fi-> errbuf, 256, "unknown alpha option '%s'", c);
return false;
}
} else
PImage
IPA__Global_band_filter(PImage img,HV *profile)
{
#define METHOD "IPA::Global::band_filter"
dPROFILE;
PImage ret;
int spatial = 1, homomorph = 0, lw, failed = 0, LowPass = 0;
double MinVal = 0.0, Power = 2.0, CutOff = 20.0, Boost = 0.7;
double * data, * buffer = nil;
if ( sizeof(double) % 2) {
warn("%s:'double' is even-sized on this platform", METHOD);
return nil;
}
if ( !img || !kind_of(( Handle) img, CImage))
croak("%s: not an image passed", METHOD);
if ( pexist( spatial)) spatial = pget_i( spatial);
if ( pexist( homomorph)) homomorph = pget_i( homomorph);
if ( pexist( power)) Power = pget_f( power);
if ( pexist( cutoff)) CutOff = pget_f( cutoff);
if ( pexist( boost)) Boost = pget_f( boost);
if ( pexist( low)) LowPass = pget_i( low);
if ( homomorph && !spatial)
croak("%s:Cannot perform the homomorph equalization in the spatial domain", METHOD);
if ( LowPass && ( CutOff < 0.0000001))
croak("%s:cutoff is too small for low pass", METHOD);
if ( !spatial && (( img-> type & imCategory) != imComplexNumber))
croak("%s: not an im::DComplex image passed", METHOD);
ret = ( PImage) img-> self-> dup(( Handle) img);
if ( !ret) fail( "%s: Return image allocation failed");
++SvREFCNT( SvRV( ret-> mate));
if ( spatial) {
ret-> self-> set_type(( Handle) ret, imDComplex);
if ( ret-> type != imDComplex) {
warn("%s: Cannot convert image to im::DComplex", METHOD);
failed = 1;
goto EXIT;
}
}
data = ( double *) ret-> data;
lw = ret-> w * 2;
/* Take log of input image */
if ( homomorph) {
long i, k = ret-> w * ret-> h * 2;
MinVal = *data;
for ( i = 0; i < k; i += 2)
if ( MinVal > data[i])
MinVal = data[i];
for ( i = 0; i < k; i += 2)
data[i] = ( double) log(( double) ( 1.0 + data[i] - MinVal));
}
/* fft */
if ( spatial) {
if ( !pow2( img-> w))
croak("%s: image width is not a power of 2", METHOD);
if ( !pow2( img-> h))
croak("%s: image height is not a power of 2", METHOD);
buffer = malloc((sizeof(double) * ret-> w * 2));
if ( !buffer) {
warn("%s: Error allocating %d bytes", METHOD, (int)(sizeof(double) * img-> w * 2));
failed = 1;
goto EXIT;
}
fft_2d( data, ret-> w, ret-> h, FFT_DIRECT, buffer);
}
butterworth( data, ret-> w, ret-> h, homomorph, LowPass, Power, CutOff, Boost);
/* inverse fft */
if ( spatial) {
fft_2d( data, ret-> w, ret-> h, FFT_INVERSE, buffer);
free( buffer);
buffer = nil;
}
/* Take exp of input image */
if ( homomorph) {
long i, k = ret-> w * ret-> h * 2;
for ( i = 0; i < k; i += 2)
data[i] = ( double) ( exp( data[i]) - 1.0 + MinVal);
}
/* converting type back */
if ( spatial && ret-> self-> get_preserveType(( Handle) ret))
ret-> self-> set_type(( Handle) ret, img-> type);
EXIT:
free( buffer);
if ( ret)
--SvREFCNT( SvRV( ret-> mate));
return failed ? nil : ret;
#undef METHOD
}
