An Efficient Algorithm for Learning Dictionary under Coherence Constraint

<div>The mutual coherence performance for each of the learnt dictionaries. (a) Results of <svg height="11.5695pt" id="M358" style="vertical-align:-3.18152pt" version="1.1" viewbox="-0.0498162 -8.38798 33.9451 11.5695" width="33.9451pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M43 650V622C120 616 128 612 128 526V124C128 39 120 33 34 27V0H270C392 0 492 25 567 83C643 141 690 230 690 350C690 444 655 517 605 565C543 625 450 650 323 650H43ZM213 547C213 587 217 598 226 604C236 612 262 617 304 617C371 617 429 604 474 576C554 529 592 439 592 336C592 176 505 36 319 36C246 36 213 55 213 131V547Z" id="g121-66"></path><glyph.data ascent="989" descent="-360" horiz-adv-x="735" vert-adv-y="735"></glyph.data></g><g transform="matrix(.013,0,0,-0.013,9.555,0)"><path d="M135 536C164 536 186 560 186 587C186 617 164 639 136 639C109 639 85 617 85 587C85 560 109 536 135 536ZM252 0V26C188 32 181 38 181 106V451C138 433 90 420 39 412V388C99 379 102 374 102 312V106C102 38 95 32 32 26V0H252Z" id="g121-103"></path><glyph.data ascent="989" descent="-360" horiz-adv-x="268" vert-adv-y="268"></glyph.data></g><g transform="matrix(.013,0,0,-0.013,13.039,0)"><path d="M390 111C344 68 312 56 269 56C212 56 118 102 118 241C118 346 175 401 241 401C277 401 312 388 342 360C350 352 355 349 361 349C372 349 394 371 394 392C394 403 391 411 378 422C362 436 329 449 288 449H287C250 449 190 432 138 392C71 341 37 274 37 197C37 90 112 -12 238 -12C297 -12 363 32 407 90L390 111Z" id="g121-97"></path><glyph.data ascent="989" descent="-360" horiz-adv-x="423" vert-adv-y="423"></glyph.data></g><g transform="matrix(.013,0,0,-0.013,18.629,0)"><path d="M298 36L289 62C276 55 253 45 228 45C202 45 169 60 169 141V397H276C289 405 292 426 282 437H169V574L155 576L90 509V437H45L17 408L21 397H90V107C90 28 125 -12 188 -12C198 -12 213 -8 230 1L298 36Z" id="g121-114"></path><glyph.data ascent="989" descent="-360" horiz-adv-x="305" vert-adv-y="305"></glyph.data></g><g transform="matrix(.0091,0,0,-0.0091,22.679,3.132)"><path d="M384 354C435 370 515 408 515 502C515 549 494 593 459 616C426 639 384 650 308 650H45V618C127 613 130 606 130 524V127C130 45 125 38 37 33V0H262C342 0 409 12 461 40C521 73 558 124 558 192C558 295 481 336 384 352V354ZM217 365V556C217 587 221 597 229 604C238 611 261 615 288 615C382 615 421 558 421 490C421 406 374 365 266 365H217ZM217 327H264C384 327 457 284 457 183C457 80 383 38 301 38C235 38 217 55 217 127V327Z" id="g58-64"></path><glyph.data ascent="1007" descent="-369" horiz-adv-x="598" vert-adv-y="598"></glyph.data></g><g transform="matrix(.0091,0,0,-0.0091,28.093,3.132)"><path d="M46 650V618C122 613 130 611 130 522V128C130 46 123 40 40 32V0H319V32C227 40 217 42 217 128V279L292 260C303 259 322 258 338 261C436 272 534 337 534 467C534 534 508 580 469 609C428 640 371 650 299 650H46ZM217 558C217 585 220 596 228 603C235 610 256 615 284 615C367 615 435 571 435 463C435 339 358 304 291 304C256 304 229 310 217 317V558Z" id="g58-78"></path><glyph.data ascent="1007" descent="-369" horiz-adv-x="573" vert-adv-y="573"></glyph.data></g></svg> versus <svg height="9.39034pt" id="M359" style="vertical-align:-3.42943pt" version="1.1" viewbox="-0.0498162 -5.96091 6.54569 9.39034" width="6.54569pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M471 401C471 442 455 448 440 448C421 448 389 439 366 424C314 390 233 331 165 242H163L187 345C193 372 197 393 197 409C197 435 189 448 174 448C146 448 80 408 23 349L40 327C64 351 97 373 107 373C115 373 118 366 111 337L29 -4L36 -12C56 -4 83 3 110 9C123 69 136 126 150 172C227 283 336 381 377 381C392 381 396 370 379 298L326 74C290 -77 273 -172 273 -197C273 -219 316 -261 346 -261L353 -246C348 -227 352 -174 374 -66L457 310C467 352 471 381 471 401Z" id="g113-229"></path><glyph.data ascent="3473" descent="-2876" horiz-adv-x="494" vert-adv-y="494"></glyph.data></g></svg>. (b) Results of <svg height="11.6836pt" id="M360" style="vertical-align:-3.29562pt" version="1.1" viewbox="-0.0498162 -8.38798 39.7909 11.6836" width="39.7909pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M43 650V622C120 616 128 612 128 526V124C128 39 120 33 34 27V0H270C392 0 492 25 567 83C643 141 690 230 690 350C690 444 655 517 605 565C543 625 450 650 323 650H43ZM213 547C213 587 217 598 226 604C236 612 262 617 304 617C371 617 429 604 474 576C554 529 592 439 592 336C592 176 505 36 319 36C246 36 213 55 213 131V547Z" id="g121-66"></path><glyph.data ascent="989" descent="-360" horiz-adv-x="735" vert-adv-y="735"></glyph.data></g><g transform="matrix(.013,0,0,-0.013,9.555,0)"><path d="M135 536C164 536 186 560 186 587C186 617 164 639 136 639C109 639 85 617 85 587C85 560 109 536 135 536ZM252 0V26C188 32 181 38 181 106V451C138 433 90 420 39 412V388C99 379 102 374 102 312V106C102 38 95 32 32 26V0H252Z" id="g121-103"></path><glyph.data ascent="989" descent="-360" horiz-adv-x="268" vert-adv-y="268"></glyph.data></g><g transform="matrix(.013,0,0,-0.013,13.039,0)"><path d="M390 111C344 68 312 56 269 56C212 56 118 102 118 241C118 346 175 401 241 401C277 401 312 388 342 360C350 352 355 349 361 349C372 349 394 371 394 392C394 403 391 411 378 422C362 436 329 449 288 449H287C250 449 190 432 138 392C71 341 37 274 37 197C37 90 112 -12 238 -12C297 -12 363 32 407 90L390 111Z" id="g121-97"></path><glyph.data ascent="989" descent="-360" horiz-adv-x="423" vert-adv-y="423"></glyph.data></g><g transform="matrix(.013,0,0,-0.013,18.629,0)"><path d="M298 36L289 62C276 55 253 45 228 45C202 45 169 60 169 141V397H276C289 405 292 426 282 437H169V574L155 576L90 509V437H45L17 408L21 397H90V107C90 28 125 -12 188 -12C198 -12 213 -8 230 1L298 36Z" id="g121-114"></path><glyph.data ascent="989" descent="-360" horiz-adv-x="305" vert-adv-y="305"></glyph.data></g><g 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Mathematical Problems in Engineering

fig7

Figure 7

Figure 7: An Efficient Algorithm for Learning Dictionary under Coherence Constraint 