Philip P. Moltmann | d904c1e | 2018-03-19 09:26:45 -0700 | [diff] [blame^] | 1 | //--------------------------------------------------------------------------------- |
| 2 | // |
| 3 | // Little Color Management System |
| 4 | // Copyright (c) 1998-2013 Marti Maria Saguer |
| 5 | // |
| 6 | // Permission is hereby granted, free of charge, to any person obtaining |
| 7 | // a copy of this software and associated documentation files (the "Software"), |
| 8 | // to deal in the Software without restriction, including without limitation |
| 9 | // the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| 10 | // and/or sell copies of the Software, and to permit persons to whom the Software |
| 11 | // is furnished to do so, subject to the following conditions: |
| 12 | // |
| 13 | // The above copyright notice and this permission notice shall be included in |
| 14 | // all copies or substantial portions of the Software. |
| 15 | // |
| 16 | // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
| 17 | // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO |
| 18 | // THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND |
| 19 | // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE |
| 20 | // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION |
| 21 | // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION |
| 22 | // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
| 23 | // |
| 24 | //--------------------------------------------------------------------------------- |
| 25 | // |
| 26 | #include "lcms2_internal.h" |
| 27 | |
| 28 | // Tone curves are powerful constructs that can contain curves specified in diverse ways. |
| 29 | // The curve is stored in segments, where each segment can be sampled or specified by parameters. |
| 30 | // a 16.bit simplification of the *whole* curve is kept for optimization purposes. For float operation, |
| 31 | // each segment is evaluated separately. Plug-ins may be used to define new parametric schemes, |
| 32 | // each plug-in may define up to MAX_TYPES_IN_LCMS_PLUGIN functions types. For defining a function, |
| 33 | // the plug-in should provide the type id, how many parameters each type has, and a pointer to |
| 34 | // a procedure that evaluates the function. In the case of reverse evaluation, the evaluator will |
| 35 | // be called with the type id as a negative value, and a sampled version of the reversed curve |
| 36 | // will be built. |
| 37 | |
| 38 | // ----------------------------------------------------------------- Implementation |
| 39 | // Maxim number of nodes |
| 40 | #define MAX_NODES_IN_CURVE 4097 |
| 41 | #define MINUS_INF (-1E22F) |
| 42 | #define PLUS_INF (+1E22F) |
| 43 | |
| 44 | // The list of supported parametric curves |
| 45 | typedef struct _cmsParametricCurvesCollection_st { |
| 46 | |
| 47 | int nFunctions; // Number of supported functions in this chunk |
| 48 | int FunctionTypes[MAX_TYPES_IN_LCMS_PLUGIN]; // The identification types |
| 49 | int ParameterCount[MAX_TYPES_IN_LCMS_PLUGIN]; // Number of parameters for each function |
| 50 | cmsParametricCurveEvaluator Evaluator; // The evaluator |
| 51 | |
| 52 | struct _cmsParametricCurvesCollection_st* Next; // Next in list |
| 53 | |
| 54 | } _cmsParametricCurvesCollection; |
| 55 | |
| 56 | // This is the default (built-in) evaluator |
| 57 | static cmsFloat64Number DefaultEvalParametricFn(cmsInt32Number Type, const cmsFloat64Number Params[], cmsFloat64Number R); |
| 58 | |
| 59 | // The built-in list |
| 60 | static _cmsParametricCurvesCollection DefaultCurves = { |
| 61 | 9, // # of curve types |
| 62 | { 1, 2, 3, 4, 5, 6, 7, 8, 108 }, // Parametric curve ID |
| 63 | { 1, 3, 4, 5, 7, 4, 5, 5, 1 }, // Parameters by type |
| 64 | DefaultEvalParametricFn, // Evaluator |
| 65 | NULL // Next in chain |
| 66 | }; |
| 67 | |
| 68 | // Duplicates the zone of memory used by the plug-in in the new context |
| 69 | static |
| 70 | void DupPluginCurvesList(struct _cmsContext_struct* ctx, |
| 71 | const struct _cmsContext_struct* src) |
| 72 | { |
| 73 | _cmsCurvesPluginChunkType newHead = { NULL }; |
| 74 | _cmsParametricCurvesCollection* entry; |
| 75 | _cmsParametricCurvesCollection* Anterior = NULL; |
| 76 | _cmsCurvesPluginChunkType* head = (_cmsCurvesPluginChunkType*) src->chunks[CurvesPlugin]; |
| 77 | |
| 78 | _cmsAssert(head != NULL); |
| 79 | |
| 80 | // Walk the list copying all nodes |
| 81 | for (entry = head->ParametricCurves; |
| 82 | entry != NULL; |
| 83 | entry = entry ->Next) { |
| 84 | |
| 85 | _cmsParametricCurvesCollection *newEntry = ( _cmsParametricCurvesCollection *) _cmsSubAllocDup(ctx ->MemPool, entry, sizeof(_cmsParametricCurvesCollection)); |
| 86 | |
| 87 | if (newEntry == NULL) |
| 88 | return; |
| 89 | |
| 90 | // We want to keep the linked list order, so this is a little bit tricky |
| 91 | newEntry -> Next = NULL; |
| 92 | if (Anterior) |
| 93 | Anterior -> Next = newEntry; |
| 94 | |
| 95 | Anterior = newEntry; |
| 96 | |
| 97 | if (newHead.ParametricCurves == NULL) |
| 98 | newHead.ParametricCurves = newEntry; |
| 99 | } |
| 100 | |
| 101 | ctx ->chunks[CurvesPlugin] = _cmsSubAllocDup(ctx->MemPool, &newHead, sizeof(_cmsCurvesPluginChunkType)); |
| 102 | } |
| 103 | |
| 104 | // The allocator have to follow the chain |
| 105 | void _cmsAllocCurvesPluginChunk(struct _cmsContext_struct* ctx, |
| 106 | const struct _cmsContext_struct* src) |
| 107 | { |
| 108 | _cmsAssert(ctx != NULL); |
| 109 | |
| 110 | if (src != NULL) { |
| 111 | |
| 112 | // Copy all linked list |
| 113 | DupPluginCurvesList(ctx, src); |
| 114 | } |
| 115 | else { |
| 116 | static _cmsCurvesPluginChunkType CurvesPluginChunk = { NULL }; |
| 117 | ctx ->chunks[CurvesPlugin] = _cmsSubAllocDup(ctx ->MemPool, &CurvesPluginChunk, sizeof(_cmsCurvesPluginChunkType)); |
| 118 | } |
| 119 | } |
| 120 | |
| 121 | |
| 122 | // The linked list head |
| 123 | _cmsCurvesPluginChunkType _cmsCurvesPluginChunk = { NULL }; |
| 124 | |
| 125 | // As a way to install new parametric curves |
| 126 | cmsBool _cmsRegisterParametricCurvesPlugin(cmsContext ContextID, cmsPluginBase* Data) |
| 127 | { |
| 128 | _cmsCurvesPluginChunkType* ctx = ( _cmsCurvesPluginChunkType*) _cmsContextGetClientChunk(ContextID, CurvesPlugin); |
| 129 | cmsPluginParametricCurves* Plugin = (cmsPluginParametricCurves*) Data; |
| 130 | _cmsParametricCurvesCollection* fl; |
| 131 | |
| 132 | if (Data == NULL) { |
| 133 | |
| 134 | ctx -> ParametricCurves = NULL; |
| 135 | return TRUE; |
| 136 | } |
| 137 | |
| 138 | fl = (_cmsParametricCurvesCollection*) _cmsPluginMalloc(ContextID, sizeof(_cmsParametricCurvesCollection)); |
| 139 | if (fl == NULL) return FALSE; |
| 140 | |
| 141 | // Copy the parameters |
| 142 | fl ->Evaluator = Plugin ->Evaluator; |
| 143 | fl ->nFunctions = Plugin ->nFunctions; |
| 144 | |
| 145 | // Make sure no mem overwrites |
| 146 | if (fl ->nFunctions > MAX_TYPES_IN_LCMS_PLUGIN) |
| 147 | fl ->nFunctions = MAX_TYPES_IN_LCMS_PLUGIN; |
| 148 | |
| 149 | // Copy the data |
| 150 | memmove(fl->FunctionTypes, Plugin ->FunctionTypes, fl->nFunctions * sizeof(cmsUInt32Number)); |
| 151 | memmove(fl->ParameterCount, Plugin ->ParameterCount, fl->nFunctions * sizeof(cmsUInt32Number)); |
| 152 | |
| 153 | // Keep linked list |
| 154 | fl ->Next = ctx->ParametricCurves; |
| 155 | ctx->ParametricCurves = fl; |
| 156 | |
| 157 | // All is ok |
| 158 | return TRUE; |
| 159 | } |
| 160 | |
| 161 | |
| 162 | // Search in type list, return position or -1 if not found |
| 163 | static |
| 164 | int IsInSet(int Type, _cmsParametricCurvesCollection* c) |
| 165 | { |
| 166 | int i; |
| 167 | |
| 168 | for (i=0; i < c ->nFunctions; i++) |
| 169 | if (abs(Type) == c ->FunctionTypes[i]) return i; |
| 170 | |
| 171 | return -1; |
| 172 | } |
| 173 | |
| 174 | |
| 175 | // Search for the collection which contains a specific type |
| 176 | static |
| 177 | _cmsParametricCurvesCollection *GetParametricCurveByType(cmsContext ContextID, int Type, int* index) |
| 178 | { |
| 179 | _cmsParametricCurvesCollection* c; |
| 180 | int Position; |
| 181 | _cmsCurvesPluginChunkType* ctx = ( _cmsCurvesPluginChunkType*) _cmsContextGetClientChunk(ContextID, CurvesPlugin); |
| 182 | |
| 183 | for (c = ctx->ParametricCurves; c != NULL; c = c ->Next) { |
| 184 | |
| 185 | Position = IsInSet(Type, c); |
| 186 | |
| 187 | if (Position != -1) { |
| 188 | if (index != NULL) |
| 189 | *index = Position; |
| 190 | return c; |
| 191 | } |
| 192 | } |
| 193 | // If none found, revert for defaults |
| 194 | for (c = &DefaultCurves; c != NULL; c = c ->Next) { |
| 195 | |
| 196 | Position = IsInSet(Type, c); |
| 197 | |
| 198 | if (Position != -1) { |
| 199 | if (index != NULL) |
| 200 | *index = Position; |
| 201 | return c; |
| 202 | } |
| 203 | } |
| 204 | |
| 205 | return NULL; |
| 206 | } |
| 207 | |
| 208 | // Low level allocate, which takes care of memory details. nEntries may be zero, and in this case |
| 209 | // no optimation curve is computed. nSegments may also be zero in the inverse case, where only the |
| 210 | // optimization curve is given. Both features simultaneously is an error |
| 211 | static |
| 212 | cmsToneCurve* AllocateToneCurveStruct(cmsContext ContextID, cmsInt32Number nEntries, |
| 213 | cmsInt32Number nSegments, const cmsCurveSegment* Segments, |
| 214 | const cmsUInt16Number* Values) |
| 215 | { |
| 216 | cmsToneCurve* p; |
| 217 | int i; |
| 218 | |
| 219 | // We allow huge tables, which are then restricted for smoothing operations |
| 220 | if (nEntries > 65530 || nEntries < 0) { |
| 221 | cmsSignalError(ContextID, cmsERROR_RANGE, "Couldn't create tone curve of more than 65530 entries"); |
| 222 | return NULL; |
| 223 | } |
| 224 | |
| 225 | if (nEntries <= 0 && nSegments <= 0) { |
| 226 | cmsSignalError(ContextID, cmsERROR_RANGE, "Couldn't create tone curve with zero segments and no table"); |
| 227 | return NULL; |
| 228 | } |
| 229 | |
| 230 | // Allocate all required pointers, etc. |
| 231 | p = (cmsToneCurve*) _cmsMallocZero(ContextID, sizeof(cmsToneCurve)); |
| 232 | if (!p) return NULL; |
| 233 | |
| 234 | // In this case, there are no segments |
| 235 | if (nSegments <= 0) { |
| 236 | p ->Segments = NULL; |
| 237 | p ->Evals = NULL; |
| 238 | } |
| 239 | else { |
| 240 | p ->Segments = (cmsCurveSegment*) _cmsCalloc(ContextID, nSegments, sizeof(cmsCurveSegment)); |
| 241 | if (p ->Segments == NULL) goto Error; |
| 242 | |
| 243 | p ->Evals = (cmsParametricCurveEvaluator*) _cmsCalloc(ContextID, nSegments, sizeof(cmsParametricCurveEvaluator)); |
| 244 | if (p ->Evals == NULL) goto Error; |
| 245 | } |
| 246 | |
| 247 | p -> nSegments = nSegments; |
| 248 | |
| 249 | // This 16-bit table contains a limited precision representation of the whole curve and is kept for |
| 250 | // increasing xput on certain operations. |
| 251 | if (nEntries <= 0) { |
| 252 | p ->Table16 = NULL; |
| 253 | } |
| 254 | else { |
| 255 | p ->Table16 = (cmsUInt16Number*) _cmsCalloc(ContextID, nEntries, sizeof(cmsUInt16Number)); |
| 256 | if (p ->Table16 == NULL) goto Error; |
| 257 | } |
| 258 | |
| 259 | p -> nEntries = nEntries; |
| 260 | |
| 261 | // Initialize members if requested |
| 262 | if (Values != NULL && (nEntries > 0)) { |
| 263 | |
| 264 | for (i=0; i < nEntries; i++) |
| 265 | p ->Table16[i] = Values[i]; |
| 266 | } |
| 267 | |
| 268 | // Initialize the segments stuff. The evaluator for each segment is located and a pointer to it |
| 269 | // is placed in advance to maximize performance. |
| 270 | if (Segments != NULL && (nSegments > 0)) { |
| 271 | |
| 272 | _cmsParametricCurvesCollection *c; |
| 273 | |
| 274 | p ->SegInterp = (cmsInterpParams**) _cmsCalloc(ContextID, nSegments, sizeof(cmsInterpParams*)); |
| 275 | if (p ->SegInterp == NULL) goto Error; |
| 276 | |
| 277 | for (i=0; i< nSegments; i++) { |
| 278 | |
| 279 | // Type 0 is a special marker for table-based curves |
| 280 | if (Segments[i].Type == 0) |
| 281 | p ->SegInterp[i] = _cmsComputeInterpParams(ContextID, Segments[i].nGridPoints, 1, 1, NULL, CMS_LERP_FLAGS_FLOAT); |
| 282 | |
| 283 | memmove(&p ->Segments[i], &Segments[i], sizeof(cmsCurveSegment)); |
| 284 | |
| 285 | if (Segments[i].Type == 0 && Segments[i].SampledPoints != NULL) |
| 286 | p ->Segments[i].SampledPoints = (cmsFloat32Number*) _cmsDupMem(ContextID, Segments[i].SampledPoints, sizeof(cmsFloat32Number) * Segments[i].nGridPoints); |
| 287 | else |
| 288 | p ->Segments[i].SampledPoints = NULL; |
| 289 | |
| 290 | |
| 291 | c = GetParametricCurveByType(ContextID, Segments[i].Type, NULL); |
| 292 | if (c != NULL) |
| 293 | p ->Evals[i] = c ->Evaluator; |
| 294 | } |
| 295 | } |
| 296 | |
| 297 | p ->InterpParams = _cmsComputeInterpParams(ContextID, p ->nEntries, 1, 1, p->Table16, CMS_LERP_FLAGS_16BITS); |
| 298 | if (p->InterpParams != NULL) |
| 299 | return p; |
| 300 | |
| 301 | Error: |
| 302 | if (p -> Segments) _cmsFree(ContextID, p ->Segments); |
| 303 | if (p -> Evals) _cmsFree(ContextID, p -> Evals); |
| 304 | if (p ->Table16) _cmsFree(ContextID, p ->Table16); |
| 305 | _cmsFree(ContextID, p); |
| 306 | return NULL; |
| 307 | } |
| 308 | |
| 309 | |
| 310 | // Parametric Fn using floating point |
| 311 | static |
| 312 | cmsFloat64Number DefaultEvalParametricFn(cmsInt32Number Type, const cmsFloat64Number Params[], cmsFloat64Number R) |
| 313 | { |
| 314 | cmsFloat64Number e, Val, disc; |
| 315 | |
| 316 | switch (Type) { |
| 317 | |
| 318 | // X = Y ^ Gamma |
| 319 | case 1: |
| 320 | if (R < 0) { |
| 321 | |
| 322 | if (fabs(Params[0] - 1.0) < MATRIX_DET_TOLERANCE) |
| 323 | Val = R; |
| 324 | else |
| 325 | Val = 0; |
| 326 | } |
| 327 | else |
| 328 | Val = pow(R, Params[0]); |
| 329 | break; |
| 330 | |
| 331 | // Type 1 Reversed: X = Y ^1/gamma |
| 332 | case -1: |
| 333 | if (R < 0) { |
| 334 | |
| 335 | if (fabs(Params[0] - 1.0) < MATRIX_DET_TOLERANCE) |
| 336 | Val = R; |
| 337 | else |
| 338 | Val = 0; |
| 339 | } |
| 340 | else |
| 341 | Val = pow(R, 1/Params[0]); |
| 342 | break; |
| 343 | |
| 344 | // CIE 122-1966 |
| 345 | // Y = (aX + b)^Gamma | X >= -b/a |
| 346 | // Y = 0 | else |
| 347 | case 2: |
| 348 | disc = -Params[2] / Params[1]; |
| 349 | |
| 350 | if (R >= disc ) { |
| 351 | |
| 352 | e = Params[1]*R + Params[2]; |
| 353 | |
| 354 | if (e > 0) |
| 355 | Val = pow(e, Params[0]); |
| 356 | else |
| 357 | Val = 0; |
| 358 | } |
| 359 | else |
| 360 | Val = 0; |
| 361 | break; |
| 362 | |
| 363 | // Type 2 Reversed |
| 364 | // X = (Y ^1/g - b) / a |
| 365 | case -2: |
| 366 | if (R < 0) |
| 367 | Val = 0; |
| 368 | else |
| 369 | Val = (pow(R, 1.0/Params[0]) - Params[2]) / Params[1]; |
| 370 | |
| 371 | if (Val < 0) |
| 372 | Val = 0; |
| 373 | break; |
| 374 | |
| 375 | |
| 376 | // IEC 61966-3 |
| 377 | // Y = (aX + b)^Gamma | X <= -b/a |
| 378 | // Y = c | else |
| 379 | case 3: |
| 380 | disc = -Params[2] / Params[1]; |
| 381 | if (disc < 0) |
| 382 | disc = 0; |
| 383 | |
| 384 | if (R >= disc) { |
| 385 | |
| 386 | e = Params[1]*R + Params[2]; |
| 387 | |
| 388 | if (e > 0) |
| 389 | Val = pow(e, Params[0]) + Params[3]; |
| 390 | else |
| 391 | Val = 0; |
| 392 | } |
| 393 | else |
| 394 | Val = Params[3]; |
| 395 | break; |
| 396 | |
| 397 | |
| 398 | // Type 3 reversed |
| 399 | // X=((Y-c)^1/g - b)/a | (Y>=c) |
| 400 | // X=-b/a | (Y<c) |
| 401 | case -3: |
| 402 | if (R >= Params[3]) { |
| 403 | |
| 404 | e = R - Params[3]; |
| 405 | |
| 406 | if (e > 0) |
| 407 | Val = (pow(e, 1/Params[0]) - Params[2]) / Params[1]; |
| 408 | else |
| 409 | Val = 0; |
| 410 | } |
| 411 | else { |
| 412 | Val = -Params[2] / Params[1]; |
| 413 | } |
| 414 | break; |
| 415 | |
| 416 | |
| 417 | // IEC 61966-2.1 (sRGB) |
| 418 | // Y = (aX + b)^Gamma | X >= d |
| 419 | // Y = cX | X < d |
| 420 | case 4: |
| 421 | if (R >= Params[4]) { |
| 422 | |
| 423 | e = Params[1]*R + Params[2]; |
| 424 | |
| 425 | if (e > 0) |
| 426 | Val = pow(e, Params[0]); |
| 427 | else |
| 428 | Val = 0; |
| 429 | } |
| 430 | else |
| 431 | Val = R * Params[3]; |
| 432 | break; |
| 433 | |
| 434 | // Type 4 reversed |
| 435 | // X=((Y^1/g-b)/a) | Y >= (ad+b)^g |
| 436 | // X=Y/c | Y< (ad+b)^g |
| 437 | case -4: |
| 438 | e = Params[1] * Params[4] + Params[2]; |
| 439 | if (e < 0) |
| 440 | disc = 0; |
| 441 | else |
| 442 | disc = pow(e, Params[0]); |
| 443 | |
| 444 | if (R >= disc) { |
| 445 | |
| 446 | Val = (pow(R, 1.0/Params[0]) - Params[2]) / Params[1]; |
| 447 | } |
| 448 | else { |
| 449 | Val = R / Params[3]; |
| 450 | } |
| 451 | break; |
| 452 | |
| 453 | |
| 454 | // Y = (aX + b)^Gamma + e | X >= d |
| 455 | // Y = cX + f | X < d |
| 456 | case 5: |
| 457 | if (R >= Params[4]) { |
| 458 | |
| 459 | e = Params[1]*R + Params[2]; |
| 460 | |
| 461 | if (e > 0) |
| 462 | Val = pow(e, Params[0]) + Params[5]; |
| 463 | else |
| 464 | Val = Params[5]; |
| 465 | } |
| 466 | else |
| 467 | Val = R*Params[3] + Params[6]; |
| 468 | break; |
| 469 | |
| 470 | |
| 471 | // Reversed type 5 |
| 472 | // X=((Y-e)1/g-b)/a | Y >=(ad+b)^g+e), cd+f |
| 473 | // X=(Y-f)/c | else |
| 474 | case -5: |
| 475 | |
| 476 | disc = Params[3] * Params[4] + Params[6]; |
| 477 | if (R >= disc) { |
| 478 | |
| 479 | e = R - Params[5]; |
| 480 | if (e < 0) |
| 481 | Val = 0; |
| 482 | else |
| 483 | Val = (pow(e, 1.0/Params[0]) - Params[2]) / Params[1]; |
| 484 | } |
| 485 | else { |
| 486 | Val = (R - Params[6]) / Params[3]; |
| 487 | } |
| 488 | break; |
| 489 | |
| 490 | |
| 491 | // Types 6,7,8 comes from segmented curves as described in ICCSpecRevision_02_11_06_Float.pdf |
| 492 | // Type 6 is basically identical to type 5 without d |
| 493 | |
| 494 | // Y = (a * X + b) ^ Gamma + c |
| 495 | case 6: |
| 496 | e = Params[1]*R + Params[2]; |
| 497 | |
| 498 | if (e < 0) |
| 499 | Val = Params[3]; |
| 500 | else |
| 501 | Val = pow(e, Params[0]) + Params[3]; |
| 502 | break; |
| 503 | |
| 504 | // ((Y - c) ^1/Gamma - b) / a |
| 505 | case -6: |
| 506 | e = R - Params[3]; |
| 507 | if (e < 0) |
| 508 | Val = 0; |
| 509 | else |
| 510 | Val = (pow(e, 1.0/Params[0]) - Params[2]) / Params[1]; |
| 511 | break; |
| 512 | |
| 513 | |
| 514 | // Y = a * log (b * X^Gamma + c) + d |
| 515 | case 7: |
| 516 | |
| 517 | e = Params[2] * pow(R, Params[0]) + Params[3]; |
| 518 | if (e <= 0) |
| 519 | Val = Params[4]; |
| 520 | else |
| 521 | Val = Params[1]*log10(e) + Params[4]; |
| 522 | break; |
| 523 | |
| 524 | // (Y - d) / a = log(b * X ^Gamma + c) |
| 525 | // pow(10, (Y-d) / a) = b * X ^Gamma + c |
| 526 | // pow((pow(10, (Y-d) / a) - c) / b, 1/g) = X |
| 527 | case -7: |
| 528 | Val = pow((pow(10.0, (R-Params[4]) / Params[1]) - Params[3]) / Params[2], 1.0 / Params[0]); |
| 529 | break; |
| 530 | |
| 531 | |
| 532 | //Y = a * b^(c*X+d) + e |
| 533 | case 8: |
| 534 | Val = (Params[0] * pow(Params[1], Params[2] * R + Params[3]) + Params[4]); |
| 535 | break; |
| 536 | |
| 537 | |
| 538 | // Y = (log((y-e) / a) / log(b) - d ) / c |
| 539 | // a=0, b=1, c=2, d=3, e=4, |
| 540 | case -8: |
| 541 | |
| 542 | disc = R - Params[4]; |
| 543 | if (disc < 0) Val = 0; |
| 544 | else |
| 545 | Val = (log(disc / Params[0]) / log(Params[1]) - Params[3]) / Params[2]; |
| 546 | break; |
| 547 | |
| 548 | // S-Shaped: (1 - (1-x)^1/g)^1/g |
| 549 | case 108: |
| 550 | Val = pow(1.0 - pow(1 - R, 1/Params[0]), 1/Params[0]); |
| 551 | break; |
| 552 | |
| 553 | // y = (1 - (1-x)^1/g)^1/g |
| 554 | // y^g = (1 - (1-x)^1/g) |
| 555 | // 1 - y^g = (1-x)^1/g |
| 556 | // (1 - y^g)^g = 1 - x |
| 557 | // 1 - (1 - y^g)^g |
| 558 | case -108: |
| 559 | Val = 1 - pow(1 - pow(R, Params[0]), Params[0]); |
| 560 | break; |
| 561 | |
| 562 | default: |
| 563 | // Unsupported parametric curve. Should never reach here |
| 564 | return 0; |
| 565 | } |
| 566 | |
| 567 | return Val; |
| 568 | } |
| 569 | |
| 570 | // Evaluate a segmented function for a single value. Return -1 if no valid segment found . |
| 571 | // If fn type is 0, perform an interpolation on the table |
| 572 | static |
| 573 | cmsFloat64Number EvalSegmentedFn(const cmsToneCurve *g, cmsFloat64Number R) |
| 574 | { |
| 575 | int i; |
| 576 | |
| 577 | for (i = g ->nSegments-1; i >= 0 ; --i) { |
| 578 | |
| 579 | // Check for domain |
| 580 | if ((R > g ->Segments[i].x0) && (R <= g ->Segments[i].x1)) { |
| 581 | |
| 582 | // Type == 0 means segment is sampled |
| 583 | if (g ->Segments[i].Type == 0) { |
| 584 | |
| 585 | cmsFloat32Number R1 = (cmsFloat32Number) (R - g ->Segments[i].x0) / (g ->Segments[i].x1 - g ->Segments[i].x0); |
| 586 | cmsFloat32Number Out; |
| 587 | |
| 588 | // Setup the table (TODO: clean that) |
| 589 | g ->SegInterp[i]-> Table = g ->Segments[i].SampledPoints; |
| 590 | |
| 591 | g ->SegInterp[i] -> Interpolation.LerpFloat(&R1, &Out, g ->SegInterp[i]); |
| 592 | |
| 593 | return Out; |
| 594 | } |
| 595 | else |
| 596 | return g ->Evals[i](g->Segments[i].Type, g ->Segments[i].Params, R); |
| 597 | } |
| 598 | } |
| 599 | |
| 600 | return MINUS_INF; |
| 601 | } |
| 602 | |
| 603 | // Access to estimated low-res table |
| 604 | cmsUInt32Number CMSEXPORT cmsGetToneCurveEstimatedTableEntries(const cmsToneCurve* t) |
| 605 | { |
| 606 | _cmsAssert(t != NULL); |
| 607 | return t ->nEntries; |
| 608 | } |
| 609 | |
| 610 | const cmsUInt16Number* CMSEXPORT cmsGetToneCurveEstimatedTable(const cmsToneCurve* t) |
| 611 | { |
| 612 | _cmsAssert(t != NULL); |
| 613 | return t ->Table16; |
| 614 | } |
| 615 | |
| 616 | |
| 617 | // Create an empty gamma curve, by using tables. This specifies only the limited-precision part, and leaves the |
| 618 | // floating point description empty. |
| 619 | cmsToneCurve* CMSEXPORT cmsBuildTabulatedToneCurve16(cmsContext ContextID, cmsInt32Number nEntries, const cmsUInt16Number Values[]) |
| 620 | { |
| 621 | return AllocateToneCurveStruct(ContextID, nEntries, 0, NULL, Values); |
| 622 | } |
| 623 | |
| 624 | static |
| 625 | int EntriesByGamma(cmsFloat64Number Gamma) |
| 626 | { |
| 627 | if (fabs(Gamma - 1.0) < 0.001) return 2; |
| 628 | return 4096; |
| 629 | } |
| 630 | |
| 631 | |
| 632 | // Create a segmented gamma, fill the table |
| 633 | cmsToneCurve* CMSEXPORT cmsBuildSegmentedToneCurve(cmsContext ContextID, |
| 634 | cmsInt32Number nSegments, const cmsCurveSegment Segments[]) |
| 635 | { |
| 636 | int i; |
| 637 | cmsFloat64Number R, Val; |
| 638 | cmsToneCurve* g; |
| 639 | int nGridPoints = 4096; |
| 640 | |
| 641 | _cmsAssert(Segments != NULL); |
| 642 | |
| 643 | // Optimizatin for identity curves. |
| 644 | if (nSegments == 1 && Segments[0].Type == 1) { |
| 645 | |
| 646 | nGridPoints = EntriesByGamma(Segments[0].Params[0]); |
| 647 | } |
| 648 | |
| 649 | g = AllocateToneCurveStruct(ContextID, nGridPoints, nSegments, Segments, NULL); |
| 650 | if (g == NULL) return NULL; |
| 651 | |
| 652 | // Once we have the floating point version, we can approximate a 16 bit table of 4096 entries |
| 653 | // for performance reasons. This table would normally not be used except on 8/16 bits transforms. |
| 654 | for (i=0; i < nGridPoints; i++) { |
| 655 | |
| 656 | R = (cmsFloat64Number) i / (nGridPoints-1); |
| 657 | |
| 658 | Val = EvalSegmentedFn(g, R); |
| 659 | |
| 660 | // Round and saturate |
| 661 | g ->Table16[i] = _cmsQuickSaturateWord(Val * 65535.0); |
| 662 | } |
| 663 | |
| 664 | return g; |
| 665 | } |
| 666 | |
| 667 | // Use a segmented curve to store the floating point table |
| 668 | cmsToneCurve* CMSEXPORT cmsBuildTabulatedToneCurveFloat(cmsContext ContextID, cmsUInt32Number nEntries, const cmsFloat32Number values[]) |
| 669 | { |
| 670 | cmsCurveSegment Seg[3]; |
| 671 | |
| 672 | // A segmented tone curve should have function segments in the first and last positions |
| 673 | // Initialize segmented curve part up to 0 to constant value = samples[0] |
| 674 | Seg[0].x0 = MINUS_INF; |
| 675 | Seg[0].x1 = 0; |
| 676 | Seg[0].Type = 6; |
| 677 | |
| 678 | Seg[0].Params[0] = 1; |
| 679 | Seg[0].Params[1] = 0; |
| 680 | Seg[0].Params[2] = 0; |
| 681 | Seg[0].Params[3] = values[0]; |
| 682 | Seg[0].Params[4] = 0; |
| 683 | |
| 684 | // From zero to 1 |
| 685 | Seg[1].x0 = 0; |
| 686 | Seg[1].x1 = 1.0; |
| 687 | Seg[1].Type = 0; |
| 688 | |
| 689 | Seg[1].nGridPoints = nEntries; |
| 690 | Seg[1].SampledPoints = (cmsFloat32Number*) values; |
| 691 | |
| 692 | // Final segment is constant = lastsample |
| 693 | Seg[2].x0 = 1.0; |
| 694 | Seg[2].x1 = PLUS_INF; |
| 695 | Seg[2].Type = 6; |
| 696 | |
| 697 | Seg[2].Params[0] = 1; |
| 698 | Seg[2].Params[1] = 0; |
| 699 | Seg[2].Params[2] = 0; |
| 700 | Seg[2].Params[3] = values[nEntries-1]; |
| 701 | Seg[2].Params[4] = 0; |
| 702 | |
| 703 | |
| 704 | return cmsBuildSegmentedToneCurve(ContextID, 3, Seg); |
| 705 | } |
| 706 | |
| 707 | // Parametric curves |
| 708 | // |
| 709 | // Parameters goes as: Curve, a, b, c, d, e, f |
| 710 | // Type is the ICC type +1 |
| 711 | // if type is negative, then the curve is analyticaly inverted |
| 712 | cmsToneCurve* CMSEXPORT cmsBuildParametricToneCurve(cmsContext ContextID, cmsInt32Number Type, const cmsFloat64Number Params[]) |
| 713 | { |
| 714 | cmsCurveSegment Seg0; |
| 715 | int Pos = 0; |
| 716 | cmsUInt32Number size; |
| 717 | _cmsParametricCurvesCollection* c = GetParametricCurveByType(ContextID, Type, &Pos); |
| 718 | |
| 719 | _cmsAssert(Params != NULL); |
| 720 | |
| 721 | if (c == NULL) { |
| 722 | cmsSignalError(ContextID, cmsERROR_UNKNOWN_EXTENSION, "Invalid parametric curve type %d", Type); |
| 723 | return NULL; |
| 724 | } |
| 725 | |
| 726 | memset(&Seg0, 0, sizeof(Seg0)); |
| 727 | |
| 728 | Seg0.x0 = MINUS_INF; |
| 729 | Seg0.x1 = PLUS_INF; |
| 730 | Seg0.Type = Type; |
| 731 | |
| 732 | size = c->ParameterCount[Pos] * sizeof(cmsFloat64Number); |
| 733 | memmove(Seg0.Params, Params, size); |
| 734 | |
| 735 | return cmsBuildSegmentedToneCurve(ContextID, 1, &Seg0); |
| 736 | } |
| 737 | |
| 738 | |
| 739 | |
| 740 | // Build a gamma table based on gamma constant |
| 741 | cmsToneCurve* CMSEXPORT cmsBuildGamma(cmsContext ContextID, cmsFloat64Number Gamma) |
| 742 | { |
| 743 | return cmsBuildParametricToneCurve(ContextID, 1, &Gamma); |
| 744 | } |
| 745 | |
| 746 | |
| 747 | // Free all memory taken by the gamma curve |
| 748 | void CMSEXPORT cmsFreeToneCurve(cmsToneCurve* Curve) |
| 749 | { |
| 750 | cmsContext ContextID; |
| 751 | |
| 752 | // added by Xiaochuan Liu |
| 753 | // Curve->InterpParams may be null |
| 754 | if (Curve == NULL || Curve->InterpParams == NULL) return; |
| 755 | |
| 756 | ContextID = Curve ->InterpParams->ContextID; |
| 757 | |
| 758 | _cmsFreeInterpParams(Curve ->InterpParams); |
| 759 | Curve ->InterpParams = NULL; |
| 760 | |
| 761 | if (Curve -> Table16) { |
| 762 | _cmsFree(ContextID, Curve ->Table16); |
| 763 | Curve ->Table16 = NULL; |
| 764 | } |
| 765 | |
| 766 | if (Curve ->Segments) { |
| 767 | |
| 768 | cmsUInt32Number i; |
| 769 | |
| 770 | for (i=0; i < Curve ->nSegments; i++) { |
| 771 | |
| 772 | if (Curve ->Segments[i].SampledPoints) { |
| 773 | _cmsFree(ContextID, Curve ->Segments[i].SampledPoints); |
| 774 | Curve ->Segments[i].SampledPoints = NULL; |
| 775 | } |
| 776 | |
| 777 | if (Curve ->SegInterp[i] != 0) { |
| 778 | _cmsFreeInterpParams(Curve->SegInterp[i]); |
| 779 | Curve->SegInterp[i] = NULL; |
| 780 | } |
| 781 | } |
| 782 | |
| 783 | _cmsFree(ContextID, Curve ->Segments); |
| 784 | Curve ->Segments = NULL; |
| 785 | _cmsFree(ContextID, Curve ->SegInterp); |
| 786 | Curve ->SegInterp = NULL; |
| 787 | } |
| 788 | |
| 789 | if (Curve -> Evals) { |
| 790 | _cmsFree(ContextID, Curve -> Evals); |
| 791 | Curve -> Evals = NULL; |
| 792 | } |
| 793 | |
| 794 | if (Curve) { |
| 795 | _cmsFree(ContextID, Curve); |
| 796 | Curve = NULL; |
| 797 | } |
| 798 | } |
| 799 | |
| 800 | // Utility function, free 3 gamma tables |
| 801 | void CMSEXPORT cmsFreeToneCurveTriple(cmsToneCurve* Curve[3]) |
| 802 | { |
| 803 | |
| 804 | _cmsAssert(Curve != NULL); |
| 805 | |
| 806 | if (Curve[0] != NULL) cmsFreeToneCurve(Curve[0]); |
| 807 | if (Curve[1] != NULL) cmsFreeToneCurve(Curve[1]); |
| 808 | if (Curve[2] != NULL) cmsFreeToneCurve(Curve[2]); |
| 809 | |
| 810 | Curve[0] = Curve[1] = Curve[2] = NULL; |
| 811 | } |
| 812 | |
| 813 | |
| 814 | // Duplicate a gamma table |
| 815 | cmsToneCurve* CMSEXPORT cmsDupToneCurve(const cmsToneCurve* In) |
| 816 | { |
| 817 | // Xiaochuan Liu |
| 818 | // fix openpdf bug(mantis id:0055683, google id:360198) |
| 819 | // the function CurveSetElemTypeFree in cmslut.c also needs to check pointer |
| 820 | if (In == NULL || In ->InterpParams == NULL || In ->Segments == NULL || In ->Table16 == NULL) return NULL; |
| 821 | |
| 822 | return AllocateToneCurveStruct(In ->InterpParams ->ContextID, In ->nEntries, In ->nSegments, In ->Segments, In ->Table16); |
| 823 | } |
| 824 | |
| 825 | // Joins two curves for X and Y. Curves should be monotonic. |
| 826 | // We want to get |
| 827 | // |
| 828 | // y = Y^-1(X(t)) |
| 829 | // |
| 830 | cmsToneCurve* CMSEXPORT cmsJoinToneCurve(cmsContext ContextID, |
| 831 | const cmsToneCurve* X, |
| 832 | const cmsToneCurve* Y, cmsUInt32Number nResultingPoints) |
| 833 | { |
| 834 | cmsToneCurve* out = NULL; |
| 835 | cmsToneCurve* Yreversed = NULL; |
| 836 | cmsFloat32Number t, x; |
| 837 | cmsFloat32Number* Res = NULL; |
| 838 | cmsUInt32Number i; |
| 839 | |
| 840 | |
| 841 | _cmsAssert(X != NULL); |
| 842 | _cmsAssert(Y != NULL); |
| 843 | |
| 844 | Yreversed = cmsReverseToneCurveEx(nResultingPoints, Y); |
| 845 | if (Yreversed == NULL) goto Error; |
| 846 | |
| 847 | Res = (cmsFloat32Number*) _cmsCalloc(ContextID, nResultingPoints, sizeof(cmsFloat32Number)); |
| 848 | if (Res == NULL) goto Error; |
| 849 | |
| 850 | //Iterate |
| 851 | for (i=0; i < nResultingPoints; i++) { |
| 852 | |
| 853 | t = (cmsFloat32Number) i / (nResultingPoints-1); |
| 854 | x = cmsEvalToneCurveFloat(X, t); |
| 855 | Res[i] = cmsEvalToneCurveFloat(Yreversed, x); |
| 856 | } |
| 857 | |
| 858 | // Allocate space for output |
| 859 | out = cmsBuildTabulatedToneCurveFloat(ContextID, nResultingPoints, Res); |
| 860 | |
| 861 | Error: |
| 862 | |
| 863 | if (Res != NULL) _cmsFree(ContextID, Res); |
| 864 | if (Yreversed != NULL) cmsFreeToneCurve(Yreversed); |
| 865 | |
| 866 | return out; |
| 867 | } |
| 868 | |
| 869 | |
| 870 | |
| 871 | // Get the surrounding nodes. This is tricky on non-monotonic tables |
| 872 | static |
| 873 | int GetInterval(cmsFloat64Number In, const cmsUInt16Number LutTable[], const struct _cms_interp_struc* p) |
| 874 | { |
| 875 | int i; |
| 876 | int y0, y1; |
| 877 | |
| 878 | // A 1 point table is not allowed |
| 879 | if (p -> Domain[0] < 1) return -1; |
| 880 | |
| 881 | // Let's see if ascending or descending. |
| 882 | if (LutTable[0] < LutTable[p ->Domain[0]]) { |
| 883 | |
| 884 | // Table is overall ascending |
| 885 | for (i=p->Domain[0]-1; i >=0; --i) { |
| 886 | |
| 887 | y0 = LutTable[i]; |
| 888 | y1 = LutTable[i+1]; |
| 889 | |
| 890 | if (y0 <= y1) { // Increasing |
| 891 | if (In >= y0 && In <= y1) return i; |
| 892 | } |
| 893 | else |
| 894 | if (y1 < y0) { // Decreasing |
| 895 | if (In >= y1 && In <= y0) return i; |
| 896 | } |
| 897 | } |
| 898 | } |
| 899 | else { |
| 900 | // Table is overall descending |
| 901 | for (i=0; i < (int) p -> Domain[0]; i++) { |
| 902 | |
| 903 | y0 = LutTable[i]; |
| 904 | y1 = LutTable[i+1]; |
| 905 | |
| 906 | if (y0 <= y1) { // Increasing |
| 907 | if (In >= y0 && In <= y1) return i; |
| 908 | } |
| 909 | else |
| 910 | if (y1 < y0) { // Decreasing |
| 911 | if (In >= y1 && In <= y0) return i; |
| 912 | } |
| 913 | } |
| 914 | } |
| 915 | |
| 916 | return -1; |
| 917 | } |
| 918 | |
| 919 | // Reverse a gamma table |
| 920 | cmsToneCurve* CMSEXPORT cmsReverseToneCurveEx(cmsInt32Number nResultSamples, const cmsToneCurve* InCurve) |
| 921 | { |
| 922 | cmsToneCurve *out; |
| 923 | cmsFloat64Number a = 0, b = 0, y, x1, y1, x2, y2; |
| 924 | int i, j; |
| 925 | int Ascending; |
| 926 | |
| 927 | _cmsAssert(InCurve != NULL); |
| 928 | |
| 929 | // Try to reverse it analytically whatever possible |
| 930 | |
| 931 | if (InCurve ->nSegments == 1 && InCurve ->Segments[0].Type > 0 && |
| 932 | /* InCurve -> Segments[0].Type <= 5 */ |
| 933 | GetParametricCurveByType(InCurve ->InterpParams->ContextID, InCurve ->Segments[0].Type, NULL) != NULL) { |
| 934 | |
| 935 | return cmsBuildParametricToneCurve(InCurve ->InterpParams->ContextID, |
| 936 | -(InCurve -> Segments[0].Type), |
| 937 | InCurve -> Segments[0].Params); |
| 938 | } |
| 939 | |
| 940 | // Nope, reverse the table. |
| 941 | out = cmsBuildTabulatedToneCurve16(InCurve ->InterpParams->ContextID, nResultSamples, NULL); |
| 942 | if (out == NULL) |
| 943 | return NULL; |
| 944 | |
| 945 | // We want to know if this is an ascending or descending table |
| 946 | Ascending = !cmsIsToneCurveDescending(InCurve); |
| 947 | |
| 948 | // Iterate across Y axis |
| 949 | for (i=0; i < nResultSamples; i++) { |
| 950 | |
| 951 | y = (cmsFloat64Number) i * 65535.0 / (nResultSamples - 1); |
| 952 | |
| 953 | // Find interval in which y is within. |
| 954 | j = GetInterval(y, InCurve->Table16, InCurve->InterpParams); |
| 955 | if (j >= 0) { |
| 956 | |
| 957 | |
| 958 | // Get limits of interval |
| 959 | x1 = InCurve ->Table16[j]; |
| 960 | x2 = InCurve ->Table16[j+1]; |
| 961 | |
| 962 | y1 = (cmsFloat64Number) (j * 65535.0) / (InCurve ->nEntries - 1); |
| 963 | y2 = (cmsFloat64Number) ((j+1) * 65535.0 ) / (InCurve ->nEntries - 1); |
| 964 | |
| 965 | // If collapsed, then use any |
| 966 | if (x1 == x2) { |
| 967 | |
| 968 | out ->Table16[i] = _cmsQuickSaturateWord(Ascending ? y2 : y1); |
| 969 | continue; |
| 970 | |
| 971 | } else { |
| 972 | |
| 973 | // Interpolate |
| 974 | a = (y2 - y1) / (x2 - x1); |
| 975 | b = y2 - a * x2; |
| 976 | } |
| 977 | } |
| 978 | |
| 979 | out ->Table16[i] = _cmsQuickSaturateWord(a* y + b); |
| 980 | } |
| 981 | |
| 982 | |
| 983 | return out; |
| 984 | } |
| 985 | |
| 986 | // Reverse a gamma table |
| 987 | cmsToneCurve* CMSEXPORT cmsReverseToneCurve(const cmsToneCurve* InGamma) |
| 988 | { |
| 989 | _cmsAssert(InGamma != NULL); |
| 990 | |
| 991 | return cmsReverseToneCurveEx(4096, InGamma); |
| 992 | } |
| 993 | |
| 994 | // From: Eilers, P.H.C. (1994) Smoothing and interpolation with finite |
| 995 | // differences. in: Graphic Gems IV, Heckbert, P.S. (ed.), Academic press. |
| 996 | // |
| 997 | // Smoothing and interpolation with second differences. |
| 998 | // |
| 999 | // Input: weights (w), data (y): vector from 1 to m. |
| 1000 | // Input: smoothing parameter (lambda), length (m). |
| 1001 | // Output: smoothed vector (z): vector from 1 to m. |
| 1002 | |
| 1003 | static |
| 1004 | cmsBool smooth2(cmsContext ContextID, cmsFloat32Number w[], cmsFloat32Number y[], cmsFloat32Number z[], cmsFloat32Number lambda, int m) |
| 1005 | { |
| 1006 | int i, i1, i2; |
| 1007 | cmsFloat32Number *c, *d, *e; |
| 1008 | cmsBool st; |
| 1009 | |
| 1010 | |
| 1011 | c = (cmsFloat32Number*) _cmsCalloc(ContextID, MAX_NODES_IN_CURVE, sizeof(cmsFloat32Number)); |
| 1012 | d = (cmsFloat32Number*) _cmsCalloc(ContextID, MAX_NODES_IN_CURVE, sizeof(cmsFloat32Number)); |
| 1013 | e = (cmsFloat32Number*) _cmsCalloc(ContextID, MAX_NODES_IN_CURVE, sizeof(cmsFloat32Number)); |
| 1014 | |
| 1015 | if (c != NULL && d != NULL && e != NULL) { |
| 1016 | |
| 1017 | |
| 1018 | d[1] = w[1] + lambda; |
| 1019 | c[1] = -2 * lambda / d[1]; |
| 1020 | e[1] = lambda /d[1]; |
| 1021 | z[1] = w[1] * y[1]; |
| 1022 | d[2] = w[2] + 5 * lambda - d[1] * c[1] * c[1]; |
| 1023 | c[2] = (-4 * lambda - d[1] * c[1] * e[1]) / d[2]; |
| 1024 | e[2] = lambda / d[2]; |
| 1025 | z[2] = w[2] * y[2] - c[1] * z[1]; |
| 1026 | |
| 1027 | for (i = 3; i < m - 1; i++) { |
| 1028 | i1 = i - 1; i2 = i - 2; |
| 1029 | d[i]= w[i] + 6 * lambda - c[i1] * c[i1] * d[i1] - e[i2] * e[i2] * d[i2]; |
| 1030 | c[i] = (-4 * lambda -d[i1] * c[i1] * e[i1])/ d[i]; |
| 1031 | e[i] = lambda / d[i]; |
| 1032 | z[i] = w[i] * y[i] - c[i1] * z[i1] - e[i2] * z[i2]; |
| 1033 | } |
| 1034 | |
| 1035 | i1 = m - 2; i2 = m - 3; |
| 1036 | |
| 1037 | d[m - 1] = w[m - 1] + 5 * lambda -c[i1] * c[i1] * d[i1] - e[i2] * e[i2] * d[i2]; |
| 1038 | c[m - 1] = (-2 * lambda - d[i1] * c[i1] * e[i1]) / d[m - 1]; |
| 1039 | z[m - 1] = w[m - 1] * y[m - 1] - c[i1] * z[i1] - e[i2] * z[i2]; |
| 1040 | i1 = m - 1; i2 = m - 2; |
| 1041 | |
| 1042 | d[m] = w[m] + lambda - c[i1] * c[i1] * d[i1] - e[i2] * e[i2] * d[i2]; |
| 1043 | z[m] = (w[m] * y[m] - c[i1] * z[i1] - e[i2] * z[i2]) / d[m]; |
| 1044 | z[m - 1] = z[m - 1] / d[m - 1] - c[m - 1] * z[m]; |
| 1045 | |
| 1046 | for (i = m - 2; 1<= i; i--) |
| 1047 | z[i] = z[i] / d[i] - c[i] * z[i + 1] - e[i] * z[i + 2]; |
| 1048 | |
| 1049 | st = TRUE; |
| 1050 | } |
| 1051 | else st = FALSE; |
| 1052 | |
| 1053 | if (c != NULL) _cmsFree(ContextID, c); |
| 1054 | if (d != NULL) _cmsFree(ContextID, d); |
| 1055 | if (e != NULL) _cmsFree(ContextID, e); |
| 1056 | |
| 1057 | return st; |
| 1058 | } |
| 1059 | |
| 1060 | // Smooths a curve sampled at regular intervals. |
| 1061 | cmsBool CMSEXPORT cmsSmoothToneCurve(cmsToneCurve* Tab, cmsFloat64Number lambda) |
| 1062 | { |
| 1063 | cmsFloat32Number w[MAX_NODES_IN_CURVE], y[MAX_NODES_IN_CURVE], z[MAX_NODES_IN_CURVE]; |
| 1064 | int i, nItems, Zeros, Poles; |
| 1065 | |
| 1066 | if (Tab == NULL) return FALSE; |
| 1067 | |
| 1068 | if (cmsIsToneCurveLinear(Tab)) return TRUE; // Nothing to do |
| 1069 | |
| 1070 | nItems = Tab -> nEntries; |
| 1071 | |
| 1072 | if (nItems >= MAX_NODES_IN_CURVE) { |
| 1073 | cmsSignalError(Tab ->InterpParams->ContextID, cmsERROR_RANGE, "cmsSmoothToneCurve: too many points."); |
| 1074 | return FALSE; |
| 1075 | } |
| 1076 | |
| 1077 | memset(w, 0, nItems * sizeof(cmsFloat32Number)); |
| 1078 | memset(y, 0, nItems * sizeof(cmsFloat32Number)); |
| 1079 | memset(z, 0, nItems * sizeof(cmsFloat32Number)); |
| 1080 | |
| 1081 | for (i=0; i < nItems; i++) |
| 1082 | { |
| 1083 | y[i+1] = (cmsFloat32Number) Tab -> Table16[i]; |
| 1084 | w[i+1] = 1.0; |
| 1085 | } |
| 1086 | |
| 1087 | if (!smooth2(Tab ->InterpParams->ContextID, w, y, z, (cmsFloat32Number) lambda, nItems)) return FALSE; |
| 1088 | |
| 1089 | // Do some reality - checking... |
| 1090 | Zeros = Poles = 0; |
| 1091 | for (i=nItems; i > 1; --i) { |
| 1092 | |
| 1093 | if (z[i] == 0.) Zeros++; |
| 1094 | if (z[i] >= 65535.) Poles++; |
| 1095 | if (z[i] < z[i-1]) { |
| 1096 | cmsSignalError(Tab ->InterpParams->ContextID, cmsERROR_RANGE, "cmsSmoothToneCurve: Non-Monotonic."); |
| 1097 | return FALSE; |
| 1098 | } |
| 1099 | } |
| 1100 | |
| 1101 | if (Zeros > (nItems / 3)) { |
| 1102 | cmsSignalError(Tab ->InterpParams->ContextID, cmsERROR_RANGE, "cmsSmoothToneCurve: Degenerated, mostly zeros."); |
| 1103 | return FALSE; |
| 1104 | } |
| 1105 | if (Poles > (nItems / 3)) { |
| 1106 | cmsSignalError(Tab ->InterpParams->ContextID, cmsERROR_RANGE, "cmsSmoothToneCurve: Degenerated, mostly poles."); |
| 1107 | return FALSE; |
| 1108 | } |
| 1109 | |
| 1110 | // Seems ok |
| 1111 | for (i=0; i < nItems; i++) { |
| 1112 | |
| 1113 | // Clamp to cmsUInt16Number |
| 1114 | Tab -> Table16[i] = _cmsQuickSaturateWord(z[i+1]); |
| 1115 | } |
| 1116 | |
| 1117 | return TRUE; |
| 1118 | } |
| 1119 | |
| 1120 | // Is a table linear? Do not use parametric since we cannot guarantee some weird parameters resulting |
| 1121 | // in a linear table. This way assures it is linear in 12 bits, which should be enought in most cases. |
| 1122 | cmsBool CMSEXPORT cmsIsToneCurveLinear(const cmsToneCurve* Curve) |
| 1123 | { |
| 1124 | cmsUInt32Number i; |
| 1125 | int diff; |
| 1126 | |
| 1127 | _cmsAssert(Curve != NULL); |
| 1128 | |
| 1129 | for (i=0; i < Curve ->nEntries; i++) { |
| 1130 | |
| 1131 | diff = abs((int) Curve->Table16[i] - (int) _cmsQuantizeVal(i, Curve ->nEntries)); |
| 1132 | if (diff > 0x0f) |
| 1133 | return FALSE; |
| 1134 | } |
| 1135 | |
| 1136 | return TRUE; |
| 1137 | } |
| 1138 | |
| 1139 | // Same, but for monotonicity |
| 1140 | cmsBool CMSEXPORT cmsIsToneCurveMonotonic(const cmsToneCurve* t) |
| 1141 | { |
| 1142 | int n; |
| 1143 | int i, last; |
| 1144 | cmsBool lDescending; |
| 1145 | |
| 1146 | _cmsAssert(t != NULL); |
| 1147 | |
| 1148 | // Degenerated curves are monotonic? Ok, let's pass them |
| 1149 | n = t ->nEntries; |
| 1150 | if (n < 2) return TRUE; |
| 1151 | |
| 1152 | // Curve direction |
| 1153 | lDescending = cmsIsToneCurveDescending(t); |
| 1154 | |
| 1155 | if (lDescending) { |
| 1156 | |
| 1157 | last = t ->Table16[0]; |
| 1158 | |
| 1159 | for (i = 1; i < n; i++) { |
| 1160 | |
| 1161 | if (t ->Table16[i] - last > 2) // We allow some ripple |
| 1162 | return FALSE; |
| 1163 | else |
| 1164 | last = t ->Table16[i]; |
| 1165 | |
| 1166 | } |
| 1167 | } |
| 1168 | else { |
| 1169 | |
| 1170 | last = t ->Table16[n-1]; |
| 1171 | |
| 1172 | for (i = n-2; i >= 0; --i) { |
| 1173 | |
| 1174 | if (t ->Table16[i] - last > 2) |
| 1175 | return FALSE; |
| 1176 | else |
| 1177 | last = t ->Table16[i]; |
| 1178 | |
| 1179 | } |
| 1180 | } |
| 1181 | |
| 1182 | return TRUE; |
| 1183 | } |
| 1184 | |
| 1185 | // Same, but for descending tables |
| 1186 | cmsBool CMSEXPORT cmsIsToneCurveDescending(const cmsToneCurve* t) |
| 1187 | { |
| 1188 | _cmsAssert(t != NULL); |
| 1189 | |
| 1190 | return t ->Table16[0] > t ->Table16[t ->nEntries-1]; |
| 1191 | } |
| 1192 | |
| 1193 | |
| 1194 | // Another info fn: is out gamma table multisegment? |
| 1195 | cmsBool CMSEXPORT cmsIsToneCurveMultisegment(const cmsToneCurve* t) |
| 1196 | { |
| 1197 | _cmsAssert(t != NULL); |
| 1198 | |
| 1199 | return t -> nSegments > 1; |
| 1200 | } |
| 1201 | |
| 1202 | cmsInt32Number CMSEXPORT cmsGetToneCurveParametricType(const cmsToneCurve* t) |
| 1203 | { |
| 1204 | _cmsAssert(t != NULL); |
| 1205 | |
| 1206 | if (t -> nSegments != 1) return 0; |
| 1207 | return t ->Segments[0].Type; |
| 1208 | } |
| 1209 | |
| 1210 | // We need accuracy this time |
| 1211 | cmsFloat32Number CMSEXPORT cmsEvalToneCurveFloat(const cmsToneCurve* Curve, cmsFloat32Number v) |
| 1212 | { |
| 1213 | _cmsAssert(Curve != NULL); |
| 1214 | |
| 1215 | // Check for 16 bits table. If so, this is a limited-precision tone curve |
| 1216 | if (Curve ->nSegments == 0) { |
| 1217 | |
| 1218 | cmsUInt16Number In, Out; |
| 1219 | |
| 1220 | In = (cmsUInt16Number) _cmsQuickSaturateWord(v * 65535.0); |
| 1221 | Out = cmsEvalToneCurve16(Curve, In); |
| 1222 | |
| 1223 | return (cmsFloat32Number) (Out / 65535.0); |
| 1224 | } |
| 1225 | |
| 1226 | return (cmsFloat32Number) EvalSegmentedFn(Curve, v); |
| 1227 | } |
| 1228 | |
| 1229 | // We need xput over here |
| 1230 | cmsUInt16Number CMSEXPORT cmsEvalToneCurve16(const cmsToneCurve* Curve, cmsUInt16Number v) |
| 1231 | { |
| 1232 | cmsUInt16Number out; |
| 1233 | |
| 1234 | _cmsAssert(Curve != NULL); |
| 1235 | |
| 1236 | Curve ->InterpParams ->Interpolation.Lerp16(&v, &out, Curve ->InterpParams); |
| 1237 | return out; |
| 1238 | } |
| 1239 | |
| 1240 | |
| 1241 | // Least squares fitting. |
| 1242 | // A mathematical procedure for finding the best-fitting curve to a given set of points by |
| 1243 | // minimizing the sum of the squares of the offsets ("the residuals") of the points from the curve. |
| 1244 | // The sum of the squares of the offsets is used instead of the offset absolute values because |
| 1245 | // this allows the residuals to be treated as a continuous differentiable quantity. |
| 1246 | // |
| 1247 | // y = f(x) = x ^ g |
| 1248 | // |
| 1249 | // R = (yi - (xi^g)) |
| 1250 | // R2 = (yi - (xi^g))2 |
| 1251 | // SUM R2 = SUM (yi - (xi^g))2 |
| 1252 | // |
| 1253 | // dR2/dg = -2 SUM x^g log(x)(y - x^g) |
| 1254 | // solving for dR2/dg = 0 |
| 1255 | // |
| 1256 | // g = 1/n * SUM(log(y) / log(x)) |
| 1257 | |
| 1258 | cmsFloat64Number CMSEXPORT cmsEstimateGamma(const cmsToneCurve* t, cmsFloat64Number Precision) |
| 1259 | { |
| 1260 | cmsFloat64Number gamma, sum, sum2; |
| 1261 | cmsFloat64Number n, x, y, Std; |
| 1262 | cmsUInt32Number i; |
| 1263 | |
| 1264 | _cmsAssert(t != NULL); |
| 1265 | |
| 1266 | sum = sum2 = n = 0; |
| 1267 | |
| 1268 | // Excluding endpoints |
| 1269 | for (i=1; i < (MAX_NODES_IN_CURVE-1); i++) { |
| 1270 | |
| 1271 | x = (cmsFloat64Number) i / (MAX_NODES_IN_CURVE-1); |
| 1272 | y = (cmsFloat64Number) cmsEvalToneCurveFloat(t, (cmsFloat32Number) x); |
| 1273 | |
| 1274 | // Avoid 7% on lower part to prevent |
| 1275 | // artifacts due to linear ramps |
| 1276 | |
| 1277 | if (y > 0. && y < 1. && x > 0.07) { |
| 1278 | |
| 1279 | gamma = log(y) / log(x); |
| 1280 | sum += gamma; |
| 1281 | sum2 += gamma * gamma; |
| 1282 | n++; |
| 1283 | } |
| 1284 | } |
| 1285 | |
| 1286 | // Take a look on SD to see if gamma isn't exponential at all |
| 1287 | Std = sqrt((n * sum2 - sum * sum) / (n*(n-1))); |
| 1288 | |
| 1289 | if (Std > Precision) |
| 1290 | return -1.0; |
| 1291 | |
| 1292 | return (sum / n); // The mean |
| 1293 | } |