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Total variation denoising

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2048: 1222: 715:, however, the total variation term plays an increasingly strong role, which forces the result to have smaller total variation, at the expense of being less like the input (noisy) signal. Thus, the choice of regularization parameter is critical to achieving just the right amount of noise removal. 1512: 1891: 20: 2152: 918: 105: 899: 1723: 1876: 441: 1391: 2043:{\displaystyle {\begin{cases}\nabla \cdot \left({\nabla u \over {\|\nabla u\|}}\right)+\lambda (f-u)=0,\quad &u\in \Omega \\{\partial u \over {\partial n}}=0,\quad &u\in \partial \Omega \end{cases}}} 68:
is high. According to this principle, reducing the total variation of the signal—subject to it being a close match to the original signal—removes unwanted detail whilst preserving important details such as
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Application of 1D total-variation denoising to a signal obtained from a single-molecule experiment. Gray is the original signal, black is the denoised signal.
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which reduce noise but at the same time smooth away edges to a greater or lesser degree. By contrast, total variation denoising is a remarkably effective
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From this functional, the Euler-Lagrange equation for minimization – assuming no time-dependence – gives us the nonlinear
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Strong, D.; Chan, T. (2003). "Edge-preserving and scale-dependent properties of total variation regularization".
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So the total-variation denoising problem amounts to minimizing the following discrete functional over the signal
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For some numerical algorithms, it is preferable to instead solve the time-dependent version of the ROF equation:
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Rudin, L. I.; Osher, S.; Fatemi, E. (1992). "Nonlinear total variation based noise removal algorithms".
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Example of application of the Rudin et al. total variation denoising technique to an image corrupted by
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Chambolle, A. (2004). "An algorithm for total variation minimization and applications".
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is smooth, the total variation is equivalent to the integral of the gradient magnitude:
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over a 2D space. ROF showed that the minimization problem we are looking to solve is:
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as initial condition. This was the original approach. Alternatively, since this is a
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This noise removal technique has advantages over simple techniques such as
27:. This example created using demo_tv.m by Guy Gilboa, see external links. 2449:
TVDIP: Full-featured Matlab 1D total variation denoising implementation.
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The Rudin–Osher–Fatemi model was a pivotal component in producing the
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The standard total-variation denoising problem is still of the form
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in the mid-2000s, there are many algorithms, such as the split-
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plays a critical role in the denoising process. When
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Rudin, 3047: 2486: 2472: 2464: 2359:Journal of Mathematical Imaging and Vision 2330: 2328: 1793: 1423: 2459:TV-L1 image denoising algorithm in Matlab 2370: 2265: 2103: 2093: 2070: 2060: 2058: 1999: 1989: 1923: 1913: 1895: 1893: 1861: 1850: 1824: 1798: 1769: 1763: 1733: 1708: 1690: 1665: 1653: 1630: 1610: 1598:{\textstyle \operatorname {TV} (\Omega )} 1578: 1558: 1542:{\textstyle \operatorname {BV} (\Omega )} 1522: 1497: 1491: 1469: 1455: 1434: 1399: 1393: 1370: 1350: 1241: 1235: 1206: 1194: 1169: 1160: 1152: 1140: 1115: 1106: 1094: 1079: 1074: 1061: 1036: 1027: 1025: 1014: 1009: 996: 971: 962: 960: 948: 926: 920: 883: 878: 865: 840: 831: 822: 817: 804: 779: 770: 768: 756: 735: 694: 668: 648: 615: 609: 580: 574: 549: 543: 481: 457: 451: 424: 414: 401: 388: 374: 348: 324: 318: 297: 291: 270: 264: 243: 237: 211: 205: 186: 177: 171: 150: 126: 120: 1345:Suppose that we are given a noisy image 286:, that has smaller total variation than 2962:Signal-to-interference-plus-noise ratio 2239: 2237: 2235: 2231: 1337:, that solve variants of this problem. 2778:Equivalent pulse code modulation noise 2335:Little, M. A.; Jones, Nick S. (2010). 2454:Efficient Primal-Dual Total Variation 1365:and wish to compute a denoised image 7: 2901:(energy per symbol to noise density) 708:{\displaystyle \lambda \to \infty } 2972:Signal-to-quantization-noise ratio 2381:10.1023/B:JMIV.0000011325.36760.1e 2107: 2096: 2083: 2071: 2063: 2030: 2027: 2000: 1992: 1982: 1927: 1916: 1903: 1812: 1799: 1785: 1699: 1691: 1675: 1589: 1560: 1533: 1470: 1444: 1415: 1250: 702: 483: 350: 14: 2886:(energy per bit to noise density) 2854:Carrier-to-receiver noise density 2768:Effective input noise temperature 2497:(physics and telecommunications) 1329:Due in part to much research in 565:, we can derive a corresponding 3109:Block-matching and 3D filtering 2957:Signal-to-noise ratio (imaging) 2808:Noise, vibration, and harshness 2018: 1973: 61:, that is, the integral of the 3166:Partial differential equations 2141: 2129: 1961: 1949: 1847: 1834: 1788: 1782: 1678: 1672: 1592: 1586: 1536: 1530: 1488: 1475: 1447: 1441: 1418: 1412: 1289: 1286: 1280: 1268: 1256: 1247: 1207: 1161: 1153: 1107: 1075: 1028: 1010: 963: 938: 932: 879: 832: 818: 771: 746: 740: 699: 519: 513: 501: 489: 421: 394: 368: 356: 212: 178: 161: 155: 51:, is a noise removal process ( 45:total variation regularization 1: 2642:Additive white Gaussian noise 1883:partial differential equation 1549:is the set of functions with 3018:Interference (communication) 2925:Signal-to-interference ratio 2915:Signal, noise and distortion 2276:10.1016/0167-2789(92)90242-f 2773:Equivalent noise resistance 2163:first image of a black hole 723:We now consider 2D signals 3182: 2311:10.1088/0266-5611/19/6/059 1298:{\displaystyle \min _{y},} 682:{\displaystyle \lambda =0} 3068:Total variation denoising 2402:Getreuer, Pascal (2012). 635:Regularization properties 49:total variation filtering 41:total variation denoising 2195:Digital image processing 2190:Chambolle-Pock algorithm 1625:is a penalty term. When 656:{\displaystyle \lambda } 2982:Contrast-to-noise ratio 2344:ICASSP 2010 Proceedings 2185:Basis pursuit denoising 1747:{\textstyle \|\cdot \|} 1566:{\displaystyle \Omega } 567:Euler–Lagrange equation 2905:Modulation error ratio 2840:Carrier-to-noise ratio 2803:Noise spectral density 2148: 2044: 1872: 1748: 1719: 1639: 1619: 1599: 1567: 1543: 1508: 1379: 1359: 1341:Rudin–Osher–Fatemi PDE 1299: 1218: 895: 709: 683: 657: 625: 590: 559: 529: 467: 437: 334: 307: 280: 253: 232:Given an input signal 223: 136: 109: 94:edge-preserving filter 28: 3120:Denoising autoencoder 3094:Anisotropic diffusion 2939:Signal-to-noise ratio 2783:Impulse noise (audio) 2698:Johnson–Nyquist noise 2586:Government regulation 2175:Anisotropic diffusion 2149: 2045: 1873: 1749: 1720: 1640: 1620: 1618:{\textstyle \lambda } 1600: 1568: 1544: 1509: 1380: 1360: 1300: 1219: 896: 710: 684: 658: 626: 624:{\displaystyle y_{n}} 591: 589:{\displaystyle x_{n}} 560: 558:{\displaystyle y_{n}} 530: 468: 466:{\displaystyle y_{n}} 438: 335: 333:{\displaystyle x_{n}} 308: 306:{\displaystyle x_{n}} 281: 279:{\displaystyle y_{n}} 254: 252:{\displaystyle x_{n}} 224: 137: 135:{\displaystyle x_{n}} 107: 22: 3003:List of noise topics 2057: 1892: 1762: 1732: 1652: 1629: 1609: 1577: 1557: 1521: 1392: 1369: 1349: 1234: 919: 734: 693: 667: 647: 608: 573: 542: 480: 450: 347: 317: 290: 263: 236: 149: 119: 2763:Circuit noise level 2758:Channel noise level 2303:2003InvPr..19S.165S 2258:1992PhyD...60..259R 602:convex optimization 2819:Pseudorandom noise 2709:Quantization error 2520:Noise cancellation 2200:Lasso (statistics) 2144: 2040: 2035: 1868: 1792: 1744: 1715: 1635: 1615: 1595: 1563: 1539: 1504: 1422: 1375: 1355: 1331:compressed sensing 1324:primal dual method 1295: 1246: 1214: 1105: 959: 891: 767: 705: 679: 653: 621: 600:, techniques from 586: 555: 525: 463: 433: 393: 330: 313:but is "close" to 303: 276: 249: 219: 176: 132: 110: 29: 3156:Signal processing 3151:Nonlinear filters 3138: 3137: 3134: 3133: 3073:Wavelet denoising 3033:Thermal radiation 3028:Spectrum analyzer 2824:Statistical noise 2648:Atmospheric noise 2545:Noise temperature 2530:Noise measurement 2510:Acoustic quieting 2215:Signal processing 2180:Bounded variation 2117: 2078: 2007: 1937: 1832: 1765: 1551:bounded variation 1463: 1395: 1378:{\displaystyle u} 1358:{\displaystyle f} 1237: 1090: 1085: 1020: 944: 889: 752: 598:convex functional 384: 382: 167: 33:signal processing 3173: 3161:Image processing 3126:Deep Image Prior 3115:Shrinkage Fields 3099:Bilateral filter 3048: 2653:Background noise 2550:Phase distortion 2488: 2481: 2474: 2465: 2436: 2435: 2433: 2432: 2417: 2411: 2410: 2408: 2399: 2393: 2392: 2374: 2354: 2348: 2347: 2341: 2332: 2323: 2322: 2297:(6): S165–S187. 2291:Inverse Problems 2286: 2280: 2279: 2269: 2252:(1–4): 259–268. 2241: 2153: 2151: 2150: 2145: 2122: 2118: 2116: 2102: 2094: 2079: 2077: 2069: 2061: 2049: 2047: 2046: 2041: 2039: 2038: 2008: 2006: 1998: 1990: 1942: 1938: 1936: 1922: 1914: 1877: 1875: 1874: 1869: 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2801: 2799: 2798:Noise shaping 2796: 2794: 2791: 2789: 2786: 2784: 2781: 2779: 2776: 2774: 2771: 2769: 2766: 2764: 2761: 2759: 2756: 2755: 2753: 2747: 2739: 2736: 2734: 2731: 2729: 2726: 2725: 2723: 2721: 2718: 2716: 2713: 2711:(or q. noise) 2710: 2707: 2705: 2702: 2699: 2696: 2694: 2691: 2689: 2686: 2684: 2681: 2679: 2676: 2674: 2673:Flicker noise 2671: 2669: 2666: 2664: 2661: 2659: 2656: 2654: 2651: 2649: 2646: 2643: 2640: 2639: 2637: 2633: 2627: 2624: 2622: 2619: 2617: 2616:Sound masking 2614: 2612: 2609: 2607: 2604: 2602: 2599: 2597: 2594: 2592: 2589: 2587: 2584: 2582: 2579: 2577: 2574: 2572: 2569: 2567: 2564: 2563: 2561: 2557: 2551: 2548: 2546: 2543: 2541: 2538: 2536: 2533: 2531: 2528: 2526: 2525:Noise control 2523: 2521: 2518: 2516: 2513: 2511: 2508: 2507: 2505: 2501: 2496: 2489: 2484: 2482: 2477: 2475: 2470: 2469: 2466: 2460: 2457: 2455: 2452: 2450: 2447: 2446: 2442: 2426: 2422: 2416: 2413: 2405: 2398: 2395: 2390: 2386: 2382: 2378: 2373: 2368: 2364: 2360: 2353: 2350: 2345: 2338: 2331: 2329: 2325: 2320: 2316: 2312: 2308: 2304: 2300: 2296: 2292: 2285: 2282: 2277: 2273: 2268: 2263: 2259: 2255: 2251: 2247: 2240: 2238: 2236: 2232: 2225: 2221: 2218: 2216: 2213: 2211: 2208: 2206: 2203: 2201: 2198: 2196: 2193: 2191: 2188: 2186: 2183: 2181: 2178: 2176: 2173: 2172: 2168: 2166: 2164: 2156: 2154: 2138: 2135: 2132: 2126: 2123: 2119: 2110: 2099: 2090: 2086: 2080: 2074: 2066: 2050: 2024: 2021: 2015: 2012: 2009: 2003: 1995: 1979: 1976: 1970: 1967: 1964: 1958: 1955: 1952: 1946: 1943: 1939: 1930: 1919: 1910: 1906: 1897: 1886: 1884: 1881: 1865: 1862: 1857: 1851: 1843: 1840: 1837: 1829: 1826: 1821: 1815: 1805: 1795: 1779: 1776: 1773: 1770: 1757: 1738: 1712: 1709: 1702: 1687: 1683: 1669: 1666: 1658: 1648: 1647: 1646: 1632: 1612: 1583: 1580: 1552: 1527: 1524: 1501: 1498: 1492: 1484: 1481: 1478: 1466: 1460: 1457: 1452: 1438: 1435: 1427: 1409: 1406: 1403: 1400: 1388: 1387: 1386: 1372: 1352: 1340: 1338: 1336: 1332: 1327: 1325: 1321: 1316: 1311: 1292: 1283: 1277: 1274: 1271: 1265: 1262: 1259: 1253: 1242: 1230: 1229: 1228: 1211: 1201: 1198: 1195: 1191: 1187: 1182: 1179: 1176: 1173: 1170: 1166: 1157: 1147: 1144: 1141: 1137: 1133: 1128: 1125: 1122: 1119: 1116: 1112: 1101: 1098: 1095: 1091: 1087: 1080: 1068: 1065: 1062: 1058: 1054: 1049: 1046: 1043: 1040: 1037: 1033: 1022: 1015: 1003: 1000: 997: 993: 989: 984: 981: 978: 975: 972: 968: 955: 952: 949: 945: 941: 935: 927: 923: 915: 914: 913: 911: 907: 884: 872: 869: 866: 862: 858: 853: 850: 847: 844: 841: 837: 828: 823: 811: 808: 805: 801: 797: 792: 789: 786: 783: 780: 776: 763: 760: 757: 753: 749: 743: 737: 730: 729: 728: 726: 718: 716: 696: 676: 673: 670: 650: 642: 634: 632: 616: 612: 603: 599: 581: 577: 568: 550: 546: 522: 516: 510: 507: 504: 498: 495: 492: 486: 476: 475: 474: 458: 454: 430: 425: 415: 411: 407: 402: 398: 389: 385: 379: 376: 371: 365: 362: 359: 353: 343: 342: 341: 325: 321: 298: 294: 271: 267: 244: 240: 216: 206: 202: 198: 193: 190: 187: 183: 172: 168: 164: 158: 152: 145: 144: 143: 127: 123: 115: 106: 99: 97: 95: 91: 87: 82: 80: 76: 72: 67: 64: 60: 59: 54: 50: 46: 42: 38: 34: 26: 21: 3067: 2985: 2975: 2965: 2950: 2946: 2942: 2932: 2928: 2918: 2908: 2889: 2874: 2867: 2861: 2857: 2847: 2843: 2788:Noise figure 2749:Engineering 2738:Worley noise 2668:Cosmic noise 2591:Human health 2429:. Retrieved 2427:. 2019-04-15 2424: 2415: 2397: 2362: 2358: 2352: 2343: 2294: 2290: 2284: 2249: 2245: 2160: 2157:Applications 2052: 1888: 1727: 1516: 1344: 1328: 1314: 1309: 1307: 1226: 903: 724: 722: 638: 537: 445: 231: 111: 83: 78: 56: 48: 44: 40: 30: 2814:Phase noise 2793:Noise floor 2728:Value noise 2720:White noise 2663:Burst noise 2581:Environment 2576:Electronics 2559:Noise in... 2535:Noise power 3145:Categories 3082:2D (Image) 2715:Shot noise 2704:Pink noise 2688:Infrasound 2683:Grey noise 2515:Distortion 2431:2019-08-04 2226:References 1312:is the 2D 643:parameter 3008:Acoustics 2571:Buildings 2389:207622122 2367:CiteSeerX 2365:: 89–97. 2319:250761777 2262:CiteSeerX 2246:Physica D 2136:− 2127:λ 2114:‖ 2108:∇ 2105:‖ 2097:∇ 2087:⋅ 2084:∇ 2072:∂ 2064:∂ 2031:Ω 2028:∂ 2025:∈ 2001:∂ 1993:∂ 1983:Ω 1980:∈ 1956:− 1947:λ 1934:‖ 1928:∇ 1925:‖ 1917:∇ 1907:⋅ 1904:∇ 1841:− 1827:λ 1819:‖ 1813:∇ 1810:‖ 1800:Ω 1796:∫ 1786:Ω 1780:⁡ 1774:∈ 1742:‖ 1739:⋅ 1736:‖ 1706:‖ 1700:∇ 1697:‖ 1692:Ω 1688:∫ 1676:Ω 1670:⁡ 1663:‖ 1656:‖ 1613:λ 1590:Ω 1584:⁡ 1561:Ω 1534:Ω 1528:⁡ 1482:− 1471:Ω 1467:∫ 1458:λ 1445:Ω 1439:⁡ 1432:‖ 1425:‖ 1416:Ω 1410:⁡ 1404:∈ 1275:λ 1254:⁡ 1188:− 1134:− 1092:∑ 1055:− 990:− 946:∑ 906:isotropic 859:− 798:− 754:∑ 703:∞ 700:→ 697:λ 671:λ 651:λ 508:λ 487:⁡ 408:− 386:∑ 354:⁡ 199:− 169:∑ 79:ROF model 66:magnitude 3042:Denoise 2169:See also 1880:elliptic 908:and not 75:S. Osher 3051:General 3044:methods 2949:,  2503:General 2299:Bibcode 2254:Bibcode 1754:is the 904:and is 3111:(BM3D) 2833:Ratios 2693:Jitter 2644:(AWGN) 2596:Images 2387:  2369:  2317:  2264:  1728:where 1517:where 1308:where 112:For a 53:filter 3122:(DAE) 2919:SINAD 2869:dBrnC 2810:(NVH) 2751:terms 2626:Video 2611:Ships 2606:Rooms 2601:Radio 2566:Audio 2495:Noise 2407:(PDF) 2385:S2CID 2340:(PDF) 2315:S2CID 928:aniso 71:edges 2976:SQNR 2966:SINR 2425:IPAM 1320:norm 639:The 2986:CNR 2951:SNR 2909:MER 2377:doi 2307:doi 2272:doi 1767:min 1397:min 1239:min 88:or 47:or 31:In 3147:: 2895:/N 2880:/N 2862:kT 2423:. 2383:. 2375:. 2363:20 2361:. 2342:. 2327:^ 2313:. 2305:. 2295:19 2293:. 2270:. 2260:. 2250:60 2248:. 2234:^ 2165:. 1885:: 1777:BV 1667:TV 1581:TV 1573:, 1525:BV 1436:TV 1407:BV 1326:. 631:. 473:: 81:. 39:, 2988:) 2984:( 2978:) 2974:( 2968:) 2964:( 2953:) 2947:N 2945:/ 2943:S 2941:( 2935:) 2933:I 2931:/ 2929:S 2927:( 2921:) 2917:( 2911:) 2907:( 2897:0 2893:s 2891:E 2882:0 2878:b 2876:E 2864:) 2860:/ 2858:C 2856:( 2850:) 2848:N 2846:/ 2844:C 2842:( 2487:e 2480:t 2473:v 2434:. 2409:. 2391:. 2379:: 2321:. 2309:: 2301:: 2278:. 2274:: 2256:: 2142:) 2139:u 2133:f 2130:( 2124:+ 2120:) 2111:u 2100:u 2091:( 2081:= 2075:t 2067:u 2022:u 2016:, 2013:0 2010:= 2004:n 1996:u 1977:u 1971:, 1968:0 1965:= 1962:) 1959:u 1953:f 1950:( 1944:+ 1940:) 1931:u 1920:u 1911:( 1898:{ 1866:x 1863:d 1858:] 1852:2 1848:) 1844:u 1838:f 1835:( 1830:2 1822:+ 1816:u 1806:[ 1789:) 1783:( 1771:u 1713:x 1710:d 1703:u 1684:= 1679:) 1673:( 1659:u 1633:u 1593:) 1587:( 1537:) 1531:( 1502:x 1499:d 1493:2 1489:) 1485:u 1479:f 1476:( 1461:2 1453:+ 1448:) 1442:( 1428:u 1419:) 1413:( 1401:u 1373:u 1353:f 1318:2 1315:L 1310:E 1293:, 1290:] 1287:) 1284:y 1281:( 1278:V 1272:+ 1269:) 1266:y 1263:, 1260:x 1257:( 1251:E 1248:[ 1243:y 1212:. 1208:| 1202:j 1199:, 1196:i 1192:y 1183:1 1180:+ 1177:j 1174:, 1171:i 1167:y 1162:| 1158:+ 1154:| 1148:j 1145:, 1142:i 1138:y 1129:j 1126:, 1123:1 1120:+ 1117:i 1113:y 1108:| 1102:j 1099:, 1096:i 1088:= 1081:2 1076:| 1069:j 1066:, 1063:i 1059:y 1050:1 1047:+ 1044:j 1041:, 1038:i 1034:y 1029:| 1023:+ 1016:2 1011:| 1004:j 1001:, 998:i 994:y 985:j 982:, 979:1 976:+ 973:i 969:y 964:| 956:j 953:, 950:i 942:= 939:) 936:y 933:( 924:V 885:2 880:| 873:j 870:, 867:i 863:y 854:1 851:+ 848:j 845:, 842:i 838:y 833:| 829:+ 824:2 819:| 812:j 809:, 806:i 802:y 793:j 790:, 787:1 784:+ 781:i 777:y 772:| 764:j 761:, 758:i 750:= 747:) 744:y 741:( 738:V 725:y 677:0 674:= 617:n 613:y 582:n 578:x 551:n 547:y 523:. 520:) 517:y 514:( 511:V 505:+ 502:) 499:y 496:, 493:x 490:( 484:E 459:n 455:y 431:. 426:2 422:) 416:n 412:y 403:n 399:x 395:( 390:n 380:n 377:1 372:= 369:) 366:y 363:, 360:x 357:( 351:E 326:n 322:x 299:n 295:x 272:n 268:y 245:n 241:x 217:. 213:| 207:n 203:x 194:1 191:+ 188:n 184:x 179:| 173:n 165:= 162:) 159:x 156:( 153:V 128:n 124:x

Index


Gaussian noise
signal processing
image processing
filter
total variation
image gradient
magnitude
edges
S. Osher
linear smoothing
median filtering
edge-preserving filter

digital signal
Euler–Lagrange equation
convex functional
convex optimization
regularization
isotropic
differentiable
L2 norm
primal dual method
compressed sensing
Bregman method
bounded variation
Euclidean norm
elliptic
partial differential equation
first image of a black hole

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