Krita Source Code Documentation
Loading...
Searching...
No Matches
IccColorProfile::Private Struct Reference

Classes

struct  ProfileInfo
 
struct  Shared
 

Public Types

using LazyProfileInfo = KisLazyStorage<KisLazyValueWrapper<ProfileInfo>, std::function<ProfileInfo()>>
 

Public Member Functions

ProfileInfo calculateFloatUIMinMax () const
 
 Private ()
 

Public Attributes

QSharedPointer< Sharedshared
 

Detailed Description

Definition at line 65 of file IccColorProfile.cpp.

Member Typedef Documentation

◆ LazyProfileInfo

Constructor & Destructor Documentation

◆ Private()

IccColorProfile::Private::Private ( )
inline

Definition at line 84 of file IccColorProfile.cpp.

Member Function Documentation

◆ calculateFloatUIMinMax()

IccColorProfile::Private::ProfileInfo IccColorProfile::Private::calculateFloatUIMinMax ( ) const

Definition at line 486 of file IccColorProfile.cpp.

487{
488 Private::ProfileInfo info;
490
491 cmsHPROFILE cprofile = shared->lcmsProfile->lcmsProfile();
492 Q_ASSERT(cprofile);
493
494 cmsColorSpaceSignature color_space_sig = cmsGetColorSpace(cprofile);
495 unsigned int num_channels = cmsChannelsOf(color_space_sig);
496 unsigned int color_space_mask = _cmsLCMScolorSpace(color_space_sig);
497
498 Q_ASSERT(num_channels >= 1 && num_channels <= 4); // num_channels==1 is for grayscale, we need to handle it
499 Q_ASSERT(color_space_mask);
500
501 // to try to find the max range of float/doubles for this profile,
502 // pass in min/max int and make the profile convert that
503 // this is far from perfect, we need a better way, if possible to get the "bounds" of a profile
504
505 uint16_t in_min_pixel[4] = {0, 0, 0, 0};
506 uint16_t in_max_pixel[4] = {0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF};
507 qreal out_min_pixel[4] = {0, 0, 0, 0};
508 qreal out_max_pixel[4] = {0, 0, 0, 0};
509
510 cmsHTRANSFORM trans = cmsCreateTransform(
511 cprofile,
512 (COLORSPACE_SH(color_space_mask) | CHANNELS_SH(num_channels) | BYTES_SH(2)),
513 cprofile,
514 (COLORSPACE_SH(color_space_mask) | FLOAT_SH(1) | CHANNELS_SH(num_channels) | BYTES_SH(0)), //NOTE THAT 'BYTES' FIELD IS SET TO ZERO ON DLB because 8 bytes overflows the bitfield
515 INTENT_ABSOLUTE_COLORIMETRIC, 0); // does the intent matter in this case?
516 // absolute colorimetric gives bigger bounds with cmyk's Chemical Proof
517
518 if (trans) {
519 cmsDoTransform(trans, in_min_pixel, out_min_pixel, 1);
520 cmsDoTransform(trans, in_max_pixel, out_max_pixel, 1);
521 cmsDeleteTransform(trans);
522 }//else, we'll just default to [0..1] below
523
524 // Some (calibration) profiles may have a weird RGB->XYZ transformation matrix,
525 // which is not invertible. Therefore, such profile cannot be used as
526 // a workspace color profile and we should convert the image to sRGB
527 // right on image loading
528
529 // LCMS doesn't have a separate method for checking if conversion matrix
530 // is invertible, therefore we just try to create a simple transformation,
531 // where the profile is both, input and output. If the transformation
532 // is created successfully, then this profile is probably suitable for
533 // usage as a working color space.
534
535 info.canCreateCyclicTransform = bool(trans);
536
537 ret.resize(num_channels);
538 for (unsigned int i = 0; i < num_channels; ++i) {
539 if (color_space_sig == cmsSigYCbCrData) {
540 // Although YCbCr profiles are essentially LUT-based
541 // (due to the inability of ICC to represent multiple successive
542 // matrix transforms except with BtoD0 tags in V4),
543 // YCbCr is intended to be a roundtrip transform to the
544 // corresponding RGB transform (BT.601, BT.709).
545 // Force enable the full range of values.
546 ret[i].minVal = 0;
547 ret[i].maxVal = 1;
548 } else if (out_min_pixel[i] < out_max_pixel[i]) {
549 ret[i].minVal = out_min_pixel[i];
550 ret[i].maxVal = out_max_pixel[i];
551 } else {
552 // apparently we can't even guarantee that converted_to_double(0x0000) < converted_to_double(0xFFFF)
553 // assume [0..1] in such cases
554 // we need to find a really solid way of determining the bounds of a profile, if possible
555 ret[i].minVal = 0;
556 ret[i].maxVal = 1;
557 }
558 }
559
560 return info;
561}
#define INTENT_ABSOLUTE_COLORIMETRIC
Definition kis_global.h:106

References KoColorProfile::info, INTENT_ABSOLUTE_COLORIMETRIC, and shared.

Member Data Documentation

◆ shared

QSharedPointer<Shared> IccColorProfile::Private::shared

Definition at line 88 of file IccColorProfile.cpp.


The documentation for this struct was generated from the following file: