iqa 0.1.2

A single, ergonomic API over the patchwork of visual quality assessment metrics in the Rust ecosystem.
Documentation
//---------------------------------------------------------------------------------
//
//  Little Color Management System, fast floating point extensions
//  Copyright (c) 1998-2023 Marti Maria Saguer, all rights reserved
//
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// 
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// 
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
//
//---------------------------------------------------------------------------------

#include "fast_float_internal.h"

// Optimization for floating point tetrahedral interpolation
typedef struct {

    cmsContext ContextID;
    const cmsInterpParams* p;   // Tetrahedrical interpolation parameters. This is a not-owned pointer.

} FloatCMYKData;



// Precomputes tables on input devicelink. 
static
FloatCMYKData* FloatCMYKAlloc(cmsContext ContextID, const cmsInterpParams* p)
{
    FloatCMYKData* fd;

    fd = (FloatCMYKData*) _cmsMallocZero(ContextID, sizeof(FloatCMYKData));
    if (fd == NULL) return NULL;
    
    fd ->ContextID = ContextID;
    fd ->p = p;
    return fd;
}


static
int XFormSampler(CMSREGISTER const cmsFloat32Number In[], CMSREGISTER cmsFloat32Number Out[], CMSREGISTER void* Cargo)
{
    // Evaluate in 16 bits
    cmsPipelineEvalFloat(In, Out, (cmsPipeline*) Cargo);

    // Always succeed
    return TRUE;
}

cmsINLINE cmsFloat32Number LinearInterpInt(cmsFloat32Number a, cmsFloat32Number l, cmsFloat32Number h)
{
       return (h - l) * a + l;       
}

// To prevent out of bounds indexing
cmsINLINE cmsFloat32Number fclamp100(cmsFloat32Number v)
{
       return ((v < 1.0e-9f) || isnan(v)) ? 0.0f : (v > 100.0f ? 100.0f : v);       
}


// A optimized interpolation for 8-bit input.
#define DENS(i,j,k) (LutTable[(i)+(j)+(k)+OutChan])

static
void FloatCMYKCLUTEval(struct _cmstransform_struct *CMMcargo,
                      const void* Input,
                      void* Output,
                      cmsUInt32Number PixelsPerLine,
                      cmsUInt32Number LineCount,
                      const cmsStride* Stride)
{
    
    cmsFloat32Number        c, m, y, k;
    cmsFloat32Number        px, py, pz, pk;
    int                     x0, y0, z0, k0;
    int                     X0, Y0, Z0, K0, X1, Y1, Z1, K1;
    cmsFloat32Number        rx, ry, rz, rk;
    cmsFloat32Number        c0, c1 = 0, c2 = 0, c3 = 0;

    cmsUInt32Number         OutChan;
    FloatCMYKData*          pcmyk = (FloatCMYKData*) _cmsGetTransformUserData(CMMcargo);

    const cmsInterpParams*  p = pcmyk ->p;
    cmsUInt32Number        TotalOut = p -> nOutputs;
    cmsUInt32Number        TotalPlusAlpha;
    const cmsFloat32Number* LutTable = (const cmsFloat32Number*)p->Table;
    cmsUInt32Number        i, ii;
    const cmsUInt8Number*  cin;
    const cmsUInt8Number*  min;
    const cmsUInt8Number*  yin;
    const cmsUInt8Number*  kin;
    const cmsUInt8Number*  ain = NULL;

    cmsFloat32Number        Tmp1[cmsMAXCHANNELS], Tmp2[cmsMAXCHANNELS];

    cmsUInt8Number* out[cmsMAXCHANNELS];
    cmsUInt32Number SourceStartingOrder[cmsMAXCHANNELS];
    cmsUInt32Number SourceIncrements[cmsMAXCHANNELS];
    cmsUInt32Number DestStartingOrder[cmsMAXCHANNELS];
    cmsUInt32Number DestIncrements[cmsMAXCHANNELS];

    cmsUInt32Number InputFormat  = cmsGetTransformInputFormat((cmsHTRANSFORM) CMMcargo);
    cmsUInt32Number OutputFormat = cmsGetTransformOutputFormat((cmsHTRANSFORM) CMMcargo);

    cmsUInt32Number nchans, nalpha;
    cmsUInt32Number strideIn, strideOut;

    _cmsComputeComponentIncrements(InputFormat, Stride->BytesPerPlaneIn, &nchans, &nalpha, SourceStartingOrder, SourceIncrements);
    _cmsComputeComponentIncrements(OutputFormat, Stride->BytesPerPlaneOut, &nchans, &nalpha, DestStartingOrder, DestIncrements);

    if (!(_cmsGetTransformFlags((cmsHTRANSFORM)CMMcargo) & cmsFLAGS_COPY_ALPHA))
        nalpha = 0;

    strideIn = strideOut = 0;
    for (i = 0; i < LineCount; i++) {

        cin = (const cmsUInt8Number*)Input + SourceStartingOrder[0] + strideIn;
        min = (const cmsUInt8Number*)Input + SourceStartingOrder[1] + strideIn;
        yin = (const cmsUInt8Number*)Input + SourceStartingOrder[2] + strideIn;
        kin = (const cmsUInt8Number*)Input + SourceStartingOrder[3] + strideIn;

        if (nalpha)
            ain = (const cmsUInt8Number*)Input + SourceStartingOrder[4] + strideIn;

        TotalPlusAlpha = TotalOut;
        if (ain) TotalPlusAlpha++;

        for (ii = 0; ii < TotalPlusAlpha; ii++)
            out[ii] = (cmsUInt8Number*)Output + DestStartingOrder[ii] + strideOut;

        for (ii = 0; ii < PixelsPerLine; ii++) {

            c = fclamp100(*(cmsFloat32Number*)cin) / 100.0f;
            m = fclamp100(*(cmsFloat32Number*)min) / 100.0f;
            y = fclamp100(*(cmsFloat32Number*)yin) / 100.0f;
            k = fclamp100(*(cmsFloat32Number*)kin) / 100.0f;

            cin += SourceIncrements[0];
            min += SourceIncrements[1];
            yin += SourceIncrements[2];
            kin += SourceIncrements[3];

            pk = c * p->Domain[0];  // C
            px = m * p->Domain[1];  // M 
            py = y * p->Domain[2];  // Y 
            pz = k * p->Domain[3];  // K


            k0 = (int)_cmsQuickFloor(pk); rk = (pk - (cmsFloat32Number)k0);
            x0 = (int)_cmsQuickFloor(px); rx = (px - (cmsFloat32Number)x0);
            y0 = (int)_cmsQuickFloor(py); ry = (py - (cmsFloat32Number)y0);
            z0 = (int)_cmsQuickFloor(pz); rz = (pz - (cmsFloat32Number)z0);


            K0 = p->opta[3] * k0;
            K1 = K0 + (c >= 1.0 ? 0 : p->opta[3]);

            X0 = p->opta[2] * x0;
            X1 = X0 + (m >= 1.0 ? 0 : p->opta[2]);

            Y0 = p->opta[1] * y0;
            Y1 = Y0 + (y >= 1.0 ? 0 : p->opta[1]);

            Z0 = p->opta[0] * z0;
            Z1 = Z0 + (k >= 1.0 ? 0 : p->opta[0]);

            for (OutChan = 0; OutChan < TotalOut; OutChan++) {

                c0 = DENS(X0, Y0, Z0);

                if (rx >= ry && ry >= rz) {

                    c1 = DENS(X1, Y0, Z0) - c0;
                    c2 = DENS(X1, Y1, Z0) - DENS(X1, Y0, Z0);
                    c3 = DENS(X1, Y1, Z1) - DENS(X1, Y1, Z0);

                }
                else
                    if (rx >= rz && rz >= ry) {

                        c1 = DENS(X1, Y0, Z0) - c0;
                        c2 = DENS(X1, Y1, Z1) - DENS(X1, Y0, Z1);
                        c3 = DENS(X1, Y0, Z1) - DENS(X1, Y0, Z0);

                    }
                    else
                        if (rz >= rx && rx >= ry) {

                            c1 = DENS(X1, Y0, Z1) - DENS(X0, Y0, Z1);
                            c2 = DENS(X1, Y1, Z1) - DENS(X1, Y0, Z1);
                            c3 = DENS(X0, Y0, Z1) - c0;

                        }
                        else
                            if (ry >= rx && rx >= rz) {

                                c1 = DENS(X1, Y1, Z0) - DENS(X0, Y1, Z0);
                                c2 = DENS(X0, Y1, Z0) - c0;
                                c3 = DENS(X1, Y1, Z1) - DENS(X1, Y1, Z0);

                            }
                            else
                                if (ry >= rz && rz >= rx) {

                                    c1 = DENS(X1, Y1, Z1) - DENS(X0, Y1, Z1);
                                    c2 = DENS(X0, Y1, Z0) - c0;
                                    c3 = DENS(X0, Y1, Z1) - DENS(X0, Y1, Z0);

                                }
                                else
                                    if (rz >= ry && ry >= rx) {

                                        c1 = DENS(X1, Y1, Z1) - DENS(X0, Y1, Z1);
                                        c2 = DENS(X0, Y1, Z1) - DENS(X0, Y0, Z1);
                                        c3 = DENS(X0, Y0, Z1) - c0;

                                    }
                                    else {
                                        c1 = c2 = c3 = 0;
                                    }


                Tmp1[OutChan] = c0 + c1 * rx + c2 * ry + c3 * rz;

            }


            LutTable = (cmsFloat32Number*)p->Table;
            LutTable += K1;

            for (OutChan = 0; OutChan < p->nOutputs; OutChan++) {

                c0 = DENS(X0, Y0, Z0);

                if (rx >= ry && ry >= rz) {

                    c1 = DENS(X1, Y0, Z0) - c0;
                    c2 = DENS(X1, Y1, Z0) - DENS(X1, Y0, Z0);
                    c3 = DENS(X1, Y1, Z1) - DENS(X1, Y1, Z0);

                }
                else
                    if (rx >= rz && rz >= ry) {

                        c1 = DENS(X1, Y0, Z0) - c0;
                        c2 = DENS(X1, Y1, Z1) - DENS(X1, Y0, Z1);
                        c3 = DENS(X1, Y0, Z1) - DENS(X1, Y0, Z0);

                    }
                    else
                        if (rz >= rx && rx >= ry) {

                            c1 = DENS(X1, Y0, Z1) - DENS(X0, Y0, Z1);
                            c2 = DENS(X1, Y1, Z1) - DENS(X1, Y0, Z1);
                            c3 = DENS(X0, Y0, Z1) - c0;

                        }
                        else
                            if (ry >= rx && rx >= rz) {

                                c1 = DENS(X1, Y1, Z0) - DENS(X0, Y1, Z0);
                                c2 = DENS(X0, Y1, Z0) - c0;
                                c3 = DENS(X1, Y1, Z1) - DENS(X1, Y1, Z0);

                            }
                            else
                                if (ry >= rz && rz >= rx) {

                                    c1 = DENS(X1, Y1, Z1) - DENS(X0, Y1, Z1);
                                    c2 = DENS(X0, Y1, Z0) - c0;
                                    c3 = DENS(X0, Y1, Z1) - DENS(X0, Y1, Z0);

                                }
                                else
                                    if (rz >= ry && ry >= rx) {

                                        c1 = DENS(X1, Y1, Z1) - DENS(X0, Y1, Z1);
                                        c2 = DENS(X0, Y1, Z1) - DENS(X0, Y0, Z1);
                                        c3 = DENS(X0, Y0, Z1) - c0;

                                    }
                                    else {
                                        c1 = c2 = c3 = 0;
                                    }

                Tmp2[OutChan] = c0 + c1 * rx + c2 * ry + c3 * rz;
            }


            for (OutChan = 0; OutChan < p->nOutputs; OutChan++) {

                *(cmsFloat32Number*)(out[OutChan]) = LinearInterpInt(rk, Tmp1[OutChan], Tmp2[OutChan]);
                out[OutChan] += DestIncrements[OutChan];
            }

            if (ain) {
                *(cmsFloat32Number*)(out[TotalOut]) = *(cmsFloat32Number*)ain;
                ain += SourceIncrements[4];
                out[TotalOut] += DestIncrements[TotalOut];
            }
        }

        strideIn += Stride->BytesPerLineIn;
        strideOut += Stride->BytesPerLineOut;
    }
}

#undef DENS



// --------------------------------------------------------------------------------------------------------------

cmsBool OptimizeCLUTCMYKTransform(_cmsTransform2Fn* TransformFn,
                                  void** UserData,
                                  _cmsFreeUserDataFn* FreeDataFn,
                                  cmsPipeline** Lut, 
                                  cmsUInt32Number* InputFormat, 
                                  cmsUInt32Number* OutputFormat, 
                                  cmsUInt32Number* dwFlags)      
{
    cmsPipeline* OriginalLut;
    int nGridPoints;    
    cmsPipeline* OptimizedLUT = NULL;    
    cmsStage* OptimizedCLUTmpe;
    FloatCMYKData* pcmyk;
    cmsContext ContextID;
    _cmsStageCLutData* data;

    // For empty transforms, do nothing
    if (*Lut == NULL) return FALSE;

    // This is a lossy optimization! does not apply in floating-point cases
    if (!T_FLOAT(*InputFormat) || !T_FLOAT(*OutputFormat)) return FALSE;

    // Only on 8-bit
    if (T_BYTES(*InputFormat) != 4 || T_BYTES(*OutputFormat) != 4) return FALSE;

    // Only on CMYK
    if (T_COLORSPACE(*InputFormat)  != PT_CMYK) return FALSE;
   
    OriginalLut = *Lut;
   
    ContextID = cmsGetPipelineContextID(OriginalLut);
    nGridPoints = _cmsReasonableGridpointsByColorspace(cmsSigRgbData, *dwFlags);
             
    // Create the result LUT
    OptimizedLUT = cmsPipelineAlloc(cmsGetPipelineContextID(OriginalLut), 4, cmsPipelineOutputChannels(OriginalLut));
    if (OptimizedLUT == NULL) goto Error;

    
    // Allocate the CLUT for result
    OptimizedCLUTmpe = cmsStageAllocCLutFloat(ContextID, nGridPoints, 4, cmsPipelineOutputChannels(OriginalLut), NULL);

    // Add the CLUT to the destination LUT
    cmsPipelineInsertStage(OptimizedLUT, cmsAT_BEGIN, OptimizedCLUTmpe);

    // Resample the LUT
    if (!cmsStageSampleCLutFloat(OptimizedCLUTmpe, XFormSampler, (void*)OriginalLut, 0)) goto Error;

    // Set the evaluator, copy parameters   
    data = (_cmsStageCLutData*) cmsStageData(OptimizedCLUTmpe);

    pcmyk = FloatCMYKAlloc(ContextID, data ->Params);
    if (pcmyk == NULL) return FALSE;   

    // And return the obtained LUT
    cmsPipelineFree(OriginalLut);

    *Lut = OptimizedLUT;
    *TransformFn = FloatCMYKCLUTEval;
    *UserData   = pcmyk;
    *FreeDataFn = _cmsFree;
    *dwFlags &= ~cmsFLAGS_CAN_CHANGE_FORMATTER;
    return TRUE;

Error:
      
    if (OptimizedLUT != NULL) cmsPipelineFree(OptimizedLUT);

    return FALSE;    
}