efficacité de l’algorithme rvb à yuv420

J’ai écrit un algorithme pour convertir une image RVB en YUV420. J’ai passé beaucoup de temps à essayer d’accélérer les choses, mais je n’ai trouvé aucun autre moyen d’en améliorer l’efficacité. Je me tourne donc vers vous pour que vous puissiez me dire si c’est aussi bon que moi ou s’il y a un autre moyen plus efficace manière de le faire (l’algorithme est en C ++ mais C et l’assembleur sont aussi des options)

namespace { // lookup tables int lookup_m_94[] = { 0, -94, -188, -282, -376, -470, -564, -658, -752, -846, -940, -1034, -1128, -1222, -1316, -1410, -1504, -1598, -1692, -1786, -1880, -1974, -2068, -2162, -2256, -2350, -2444, -2538, -2632, -2726, -2820, -2914, -3008, -3102, -3196, -3290, -3384, -3478, -3572, -3666, -3760, -3854, -3948, -4042, -4136, -4230, -4324, -4418, -4512, -4606, -4700, -4794, -4888, -4982, -5076, -5170, -5264, -5358, -5452, -5546, -5640, -5734, -5828, -5922, -6016, -6110, -6204, -6298, -6392, -6486, -6580, -6674, -6768, -6862, -6956, -7050, -7144, -7238, -7332, -7426, -7520, -7614, -7708, -7802, -7896, -7990, -8084, -8178, -8272, -8366, -8460, -8554, -8648, -8742, -8836, -8930, -9024, -9118, -9212, -9306, -9400, -9494, -9588, -9682, -9776, -9870, -9964, -10058, -10152, -10246, -10340, -10434, -10528, -10622, -10716, -10810, -10904, -10998, -11092, -11186, -11280, -11374, -11468, -11562, -11656, -11750, -11844, -11938, -12032, -12126, -12220, -12314, -12408, -12502, -12596, -12690, -12784, -12878, -12972, -13066, -13160, -13254, -13348, -13442, -13536, -13630, -13724, -13818, -13912, -14006, -14100, -14194, -14288, -14382, -14476, -14570, -14664, -14758, -14852, -14946, -15040, -15134, -15228, -15322, -15416, -15510, -15604, -15698, -15792, -15886, -15980, -16074, -16168, -16262, -16356, -16450, -16544, -16638, -16732, -16826, -16920, -17014, -17108, -17202, -17296, -17390, -17484, -17578, -17672, -17766, -17860, -17954, -18048, -18142, -18236, -18330, -18424, -18518, -18612, -18706, -18800, -18894, -18988, -19082, -19176, -19270, -19364, -19458, -19552, -19646, -19740, -19834, -19928, -20022, -20116, -20210, -20304, -20398, -20492, -20586, -20680, -20774, -20868, -20962, -21056, -21150, -21244, -21338, -21432, -21526, -21620, -21714, -21808, -21902, -21996, -22090, -22184, -22278, -22372, -22466, -22560, -22654, -22748, -22842, -22936, -23030, -23124, -23218, -23312, -23406, -23500, -23594, -23688, -23782, -23876, -23970 }; int lookup_m_74[] = { 0, -74, -148, -222, -296, -370, -444, -518, -592, -666, -740, -814, -888, -962, -1036, -1110, -1184, -1258, -1332, -1406, -1480, -1554, -1628, -1702, -1776, -1850, -1924, -1998, -2072, -2146, -2220, -2294, -2368, -2442, -2516, -2590, -2664, -2738, -2812, -2886, -2960, -3034, -3108, -3182, -3256, -3330, -3404, -3478, -3552, -3626, -3700, -3774, -3848, -3922, -3996, -4070, -4144, -4218, -4292, -4366, -4440, -4514, -4588, -4662, -4736, -4810, -4884, -4958, -5032, -5106, -5180, -5254, -5328, -5402, -5476, -5550, -5624, -5698, -5772, -5846, -5920, -5994, -6068, -6142, -6216, -6290, -6364, -6438, -6512, -6586, -6660, -6734, -6808, -6882, -6956, -7030, -7104, -7178, -7252, -7326, -7400, -7474, -7548, -7622, -7696, -7770, -7844, -7918, -7992, -8066, -8140, -8214, -8288, -8362, -8436, -8510, -8584, -8658, -8732, -8806, -8880, -8954, -9028, -9102, -9176, -9250, -9324, -9398, -9472, -9546, -9620, -9694, -9768, -9842, -9916, -9990, -10064, -10138, -10212, -10286, -10360, -10434, -10508, -10582, -10656, -10730, -10804, -10878, -10952, -11026, -11100, -11174, -11248, -11322, -11396, -11470, -11544, -11618, -11692, -11766, -11840, -11914, -11988, -12062, -12136, -12210, -12284, -12358, -12432, -12506, -12580, -12654, -12728, -12802, -12876, -12950, -13024, -13098, -13172, -13246, -13320, -13394, -13468, -13542, -13616, -13690, -13764, -13838, -13912, -13986, -14060, -14134, -14208, -14282, -14356, -14430, -14504, -14578, -14652, -14726, -14800, -14874, -14948, -15022, -15096, -15170, -15244, -15318, -15392, -15466, -15540, -15614, -15688, -15762, -15836, -15910, -15984, -16058, -16132, -16206, -16280, -16354, -16428, -16502, -16576, -16650, -16724, -16798, -16872, -16946, -17020, -17094, -17168, -17242, -17316, -17390, -17464, -17538, -17612, -17686, -17760, -17834, -17908, -17982, -18056, -18130, -18204, -18278, -18352, -18426, -18500, -18574, -18648, -18722, -18796, -18870 }; int lookup_m_38[] = { 0, -38, -76, -114, -152, -190, -228, -266, -304, -342, -380, -418, -456, -494, -532, -570, -608, -646, -684, -722, -760, -798, -836, -874, -912, -950, -988, -1026, -1064, -1102, -1140, -1178, -1216, -1254, -1292, -1330, -1368, -1406, -1444, -1482, -1520, -1558, -1596, -1634, -1672, -1710, -1748, -1786, -1824, -1862, -1900, -1938, -1976, -2014, -2052, -2090, -2128, -2166, -2204, -2242, -2280, -2318, -2356, -2394, -2432, -2470, -2508, -2546, -2584, -2622, -2660, -2698, -2736, -2774, -2812, -2850, -2888, -2926, -2964, -3002, -3040, -3078, -3116, -3154, -3192, -3230, -3268, -3306, -3344, -3382, -3420, -3458, -3496, -3534, -3572, -3610, -3648, -3686, -3724, -3762, -3800, -3838, -3876, -3914, -3952, -3990, -4028, -4066, -4104, -4142, -4180, -4218, -4256, -4294, -4332, -4370, -4408, -4446, -4484, -4522, -4560, -4598, -4636, -4674, -4712, -4750, -4788, -4826, -4864, -4902, -4940, -4978, -5016, -5054, -5092, -5130, -5168, -5206, -5244, -5282, -5320, -5358, -5396, -5434, -5472, -5510, -5548, -5586, -5624, -5662, -5700, -5738, -5776, -5814, -5852, -5890, -5928, -5966, -6004, -6042, -6080, -6118, -6156, -6194, -6232, -6270, -6308, -6346, -6384, -6422, -6460, -6498, -6536, -6574, -6612, -6650, -6688, -6726, -6764, -6802, -6840, -6878, -6916, -6954, -6992, -7030, -7068, -7106, -7144, -7182, -7220, -7258, -7296, -7334, -7372, -7410, -7448, -7486, -7524, -7562, -7600, -7638, -7676, -7714, -7752, -7790, -7828, -7866, -7904, -7942, -7980, -8018, -8056, -8094, -8132, -8170, -8208, -8246, -8284, -8322, -8360, -8398, -8436, -8474, -8512, -8550, -8588, -8626, -8664, -8702, -8740, -8778, -8816, -8854, -8892, -8930, -8968, -9006, -9044, -9082, -9120, -9158, -9196, -9234, -9272, -9310, -9348, -9386, -9424, -9462, -9500, -9538, -9576, -9614, -9652, -9690 }; int lookup_m_18[] = { 0, -18, -36, -54, -72, -90, -108, -126, -144, -162, -180, -198, -216, -234, -252, -270, -288, -306, -324, -342, -360, -378, -396, -414, -432, -450, -468, -486, -504, -522, -540, -558, -576, -594, -612, -630, -648, -666, -684, -702, -720, -738, -756, -774, -792, -810, -828, -846, -864, -882, -900, -918, -936, -954, -972, -990, -1008, -1026, -1044, -1062, -1080, -1098, -1116, -1134, -1152, -1170, -1188, -1206, -1224, -1242, -1260, -1278, -1296, -1314, -1332, -1350, -1368, -1386, -1404, -1422, -1440, -1458, -1476, -1494, -1512, -1530, -1548, -1566, -1584, -1602, -1620, -1638, -1656, -1674, -1692, -1710, -1728, -1746, -1764, -1782, -1800, -1818, -1836, -1854, -1872, -1890, -1908, -1926, -1944, -1962, -1980, -1998, -2016, -2034, -2052, -2070, -2088, -2106, -2124, -2142, -2160, -2178, -2196, -2214, -2232, -2250, -2268, -2286, -2304, -2322, -2340, -2358, -2376, -2394, -2412, -2430, -2448, -2466, -2484, -2502, -2520, -2538, -2556, -2574, -2592, -2610, -2628, -2646, -2664, -2682, -2700, -2718, -2736, -2754, -2772, -2790, -2808, -2826, -2844, -2862, -2880, -2898, -2916, -2934, -2952, -2970, -2988, -3006, -3024, -3042, -3060, -3078, -3096, -3114, -3132, -3150, -3168, -3186, -3204, -3222, -3240, -3258, -3276, -3294, -3312, -3330, -3348, -3366, -3384, -3402, -3420, -3438, -3456, -3474, -3492, -3510, -3528, -3546, -3564, -3582, -3600, -3618, -3636, -3654, -3672, -3690, -3708, -3726, -3744, -3762, -3780, -3798, -3816, -3834, -3852, -3870, -3888, -3906, -3924, -3942, -3960, -3978, -3996, -4014, -4032, -4050, -4068, -4086, -4104, -4122, -4140, -4158, -4176, -4194, -4212, -4230, -4248, -4266, -4284, -4302, -4320, -4338, -4356, -4374, -4392, -4410, -4428, -4446, -4464, -4482, -4500, -4518, -4536, -4554, -4572, -4590 }; int lookup25[] = { 0, 25, 50, 75, 100, 125, 150, 175, 200, 225, 250, 275, 300, 325, 350, 375, 400, 425, 450, 475, 500, 525, 550, 575, 600, 625, 650, 675, 700, 725, 750, 775, 800, 825, 850, 875, 900, 925, 950, 975, 1000, 1025, 1050, 1075, 1100, 1125, 1150, 1175, 1200, 1225, 1250, 1275, 1300, 1325, 1350, 1375, 1400, 1425, 1450, 1475, 1500, 1525, 1550, 1575, 1600, 1625, 1650, 1675, 1700, 1725, 1750, 1775, 1800, 1825, 1850, 1875, 1900, 1925, 1950, 1975, 2000, 2025, 2050, 2075, 2100, 2125, 2150, 2175, 2200, 2225, 2250, 2275, 2300, 2325, 2350, 2375, 2400, 2425, 2450, 2475, 2500, 2525, 2550, 2575, 2600, 2625, 2650, 2675, 2700, 2725, 2750, 2775, 2800, 2825, 2850, 2875, 2900, 2925, 2950, 2975, 3000, 3025, 3050, 3075, 3100, 3125, 3150, 3175, 3200, 3225, 3250, 3275, 3300, 3325, 3350, 3375, 3400, 3425, 3450, 3475, 3500, 3525, 3550, 3575, 3600, 3625, 3650, 3675, 3700, 3725, 3750, 3775, 3800, 3825, 3850, 3875, 3900, 3925, 3950, 3975, 4000, 4025, 4050, 4075, 4100, 4125, 4150, 4175, 4200, 4225, 4250, 4275, 4300, 4325, 4350, 4375, 4400, 4425, 4450, 4475, 4500, 4525, 4550, 4575, 4600, 4625, 4650, 4675, 4700, 4725, 4750, 4775, 4800, 4825, 4850, 4875, 4900, 4925, 4950, 4975, 5000, 5025, 5050, 5075, 5100, 5125, 5150, 5175, 5200, 5225, 5250, 5275, 5300, 5325, 5350, 5375, 5400, 5425, 5450, 5475, 5500, 5525, 5550, 5575, 5600, 5625, 5650, 5675, 5700, 5725, 5750, 5775, 5800, 5825, 5850, 5875, 5900, 5925, 5950, 5975, 6000, 6025, 6050, 6075, 6100, 6125, 6150, 6175, 6200, 6225, 6250, 6275, 6300, 6325, 6350, 6375 }; int lookup66[] = { 0, 66, 132, 198, 264, 330, 396, 462, 528, 594, 660, 726, 792, 858, 924, 990, 1056, 1122, 1188, 1254, 1320, 1386, 1452, 1518, 1584, 1650, 1716, 1782, 1848, 1914, 1980, 2046, 2112, 2178, 2244, 2310, 2376, 2442, 2508, 2574, 2640, 2706, 2772, 2838, 2904, 2970, 3036, 3102, 3168, 3234, 3300, 3366, 3432, 3498, 3564, 3630, 3696, 3762, 3828, 3894, 3960, 4026, 4092, 4158, 4224, 4290, 4356, 4422, 4488, 4554, 4620, 4686, 4752, 4818, 4884, 4950, 5016, 5082, 5148, 5214, 5280, 5346, 5412, 5478, 5544, 5610, 5676, 5742, 5808, 5874, 5940, 6006, 6072, 6138, 6204, 6270, 6336, 6402, 6468, 6534, 6600, 6666, 6732, 6798, 6864, 6930, 6996, 7062, 7128, 7194, 7260, 7326, 7392, 7458, 7524, 7590, 7656, 7722, 7788, 7854, 7920, 7986, 8052, 8118, 8184, 8250, 8316, 8382, 8448, 8514, 8580, 8646, 8712, 8778, 8844, 8910, 8976, 9042, 9108, 9174, 9240, 9306, 9372, 9438, 9504, 9570, 9636, 9702, 9768, 9834, 9900, 9966, 10032, 10098, 10164, 10230, 10296, 10362, 10428, 10494, 10560, 10626, 10692, 10758, 10824, 10890, 10956, 11022, 11088, 11154, 11220, 11286, 11352, 11418, 11484, 11550, 11616, 11682, 11748, 11814, 11880, 11946, 12012, 12078, 12144, 12210, 12276, 12342, 12408, 12474, 12540, 12606, 12672, 12738, 12804, 12870, 12936, 13002, 13068, 13134, 13200, 13266, 13332, 13398, 13464, 13530, 13596, 13662, 13728, 13794, 13860, 13926, 13992, 14058, 14124, 14190, 14256, 14322, 14388, 14454, 14520, 14586, 14652, 14718, 14784, 14850, 14916, 14982, 15048, 15114, 15180, 15246, 15312, 15378, 15444, 15510, 15576, 15642, 15708, 15774, 15840, 15906, 15972, 16038, 16104, 16170, 16236, 16302, 16368, 16434, 16500, 16566, 16632, 16698, 16764, 16830 }; int lookup112[] = { 0, 112, 224, 336, 448, 560, 672, 784, 896, 1008, 1120, 1232, 1344, 1456, 1568, 1680, 1792, 1904, 2016, 2128, 2240, 2352, 2464, 2576, 2688, 2800, 2912, 3024, 3136, 3248, 3360, 3472, 3584, 3696, 3808, 3920, 4032, 4144, 4256, 4368, 4480, 4592, 4704, 4816, 4928, 5040, 5152, 5264, 5376, 5488, 5600, 5712, 5824, 5936, 6048, 6160, 6272, 6384, 6496, 6608, 6720, 6832, 6944, 7056, 7168, 7280, 7392, 7504, 7616, 7728, 7840, 7952, 8064, 8176, 8288, 8400, 8512, 8624, 8736, 8848, 8960, 9072, 9184, 9296, 9408, 9520, 9632, 9744, 9856, 9968, 10080, 10192, 10304, 10416, 10528, 10640, 10752, 10864, 10976, 11088, 11200, 11312, 11424, 11536, 11648, 11760, 11872, 11984, 12096, 12208, 12320, 12432, 12544, 12656, 12768, 12880, 12992, 13104, 13216, 13328, 13440, 13552, 13664, 13776, 13888, 14000, 14112, 14224, 14336, 14448, 14560, 14672, 14784, 14896, 15008, 15120, 15232, 15344, 15456, 15568, 15680, 15792, 15904, 16016, 16128, 16240, 16352, 16464, 16576, 16688, 16800, 16912, 17024, 17136, 17248, 17360, 17472, 17584, 17696, 17808, 17920, 18032, 18144, 18256, 18368, 18480, 18592, 18704, 18816, 18928, 19040, 19152, 19264, 19376, 19488, 19600, 19712, 19824, 19936, 20048, 20160, 20272, 20384, 20496, 20608, 20720, 20832, 20944, 21056, 21168, 21280, 21392, 21504, 21616, 21728, 21840, 21952, 22064, 22176, 22288, 22400, 22512, 22624, 22736, 22848, 22960, 23072, 23184, 23296, 23408, 23520, 23632, 23744, 23856, 23968, 24080, 24192, 24304, 24416, 24528, 24640, 24752, 24864, 24976, 25088, 25200, 25312, 25424, 25536, 25648, 25760, 25872, 25984, 26096, 26208, 26320, 26432, 26544, 26656, 26768, 26880, 26992, 27104, 27216, 27328, 27440, 27552, 27664, 27776, 27888, 28000, 28112, 28224, 28336, 28448, 28560 }; int lookup129[] = { 0, 129, 258, 387, 516, 645, 774, 903, 1032, 1161, 1290, 1419, 1548, 1677, 1806, 1935, 2064, 2193, 2322, 2451, 2580, 2709, 2838, 2967, 3096, 3225, 3354, 3483, 3612, 3741, 3870, 3999, 4128, 4257, 4386, 4515, 4644, 4773, 4902, 5031, 5160, 5289, 5418, 5547, 5676, 5805, 5934, 6063, 6192, 6321, 6450, 6579, 6708, 6837, 6966, 7095, 7224, 7353, 7482, 7611, 7740, 7869, 7998, 8127, 8256, 8385, 8514, 8643, 8772, 8901, 9030, 9159, 9288, 9417, 9546, 9675, 9804, 9933, 10062, 10191, 10320, 10449, 10578, 10707, 10836, 10965, 11094, 11223, 11352, 11481, 11610, 11739, 11868, 11997, 12126, 12255, 12384, 12513, 12642, 12771, 12900, 13029, 13158, 13287, 13416, 13545, 13674, 13803, 13932, 14061, 14190, 14319, 14448, 14577, 14706, 14835, 14964, 15093, 15222, 15351, 15480, 15609, 15738, 15867, 15996, 16125, 16254, 16383, 16512, 16641, 16770, 16899, 17028, 17157, 17286, 17415, 17544, 17673, 17802, 17931, 18060, 18189, 18318, 18447, 18576, 18705, 18834, 18963, 19092, 19221, 19350, 19479, 19608, 19737, 19866, 19995, 20124, 20253, 20382, 20511, 20640, 20769, 20898, 21027, 21156, 21285, 21414, 21543, 21672, 21801, 21930, 22059, 22188, 22317, 22446, 22575, 22704, 22833, 22962, 23091, 23220, 23349, 23478, 23607, 23736, 23865, 23994, 24123, 24252, 24381, 24510, 24639, 24768, 24897, 25026, 25155, 25284, 25413, 25542, 25671, 25800, 25929, 26058, 26187, 26316, 26445, 26574, 26703, 26832, 26961, 27090, 27219, 27348, 27477, 27606, 27735, 27864, 27993, 28122, 28251, 28380, 28509, 28638, 28767, 28896, 29025, 29154, 29283, 29412, 29541, 29670, 29799, 29928, 30057, 30186, 30315, 30444, 30573, 30702, 30831, 30960, 31089, 31218, 31347, 31476, 31605, 31734, 31863, 31992, 32121, 32250, 32379, 32508, 32637, 32766, 32895 }; } void Bitmap2Yuv420p(boost::uint8_t *destination, boost::uint8_t *rgb, const int &width, const int &height) { boost::uint8_t *y; boost::uint8_t *u; boost::uint8_t *v; boost::uint8_t *r; boost::uint8_t *g; boost::uint8_t *b; std::size_t image_size = width * height; std::size_t upos = image_size; std::size_t vpos = upos + upos / 4; for (std::size_t i = 0; i > 8) + 16; if (!((i / width) % 2) && !(i % 2)) { u = destination + upos++; v = destination + vpos++; *u = ((lookup_m_38[*r] + lookup_m_74[*g] + lookup112[*b]) >> 8) + 128; *v = ((lookup112[*r] + lookup_m_94[*g] + lookup_m_18[*b]) >> 8) + 128; } } } 

• Boost liste de graphes ou vec
• Calculer le minimum, le maximum et la moyenne des nombres entrés
• Comment trouver et remplacer toutes les occurrences d’une sous-chaîne dans une chaîne?
• C ++: Comment diviser une chaîne en chaînes plus petites de taille égale?
• stl map performance?

 void Bitmap2Yuv420p_calc2(uint8_t *destination, uint8_t *rgb, size_t width, size_t height) { size_t image_size = width * height; size_t upos = image_size; size_t vpos = upos + upos / 4; size_t i = 0; for( size_t line = 0; line < height; ++line ) { if( !(line % 2) ) { for( size_t x = 0; x < width; x += 2 ) { uint8_t r = rgb[3 * i]; uint8_t g = rgb[3 * i + 1]; uint8_t b = rgb[3 * i + 2]; destination[i++] = ((66*r + 129*g + 25*b) >> 8) + 16; destination[upos++] = ((-38*r + -74*g + 112*b) >> 8) + 128; destination[vpos++] = ((112*r + -94*g + -18*b) >> 8) + 128; r = rgb[3 * i]; g = rgb[3 * i + 1]; b = rgb[3 * i + 2]; destination[i++] = ((66*r + 129*g + 25*b) >> 8) + 16; } } else { for( size_t x = 0; x < width; x += 1 ) { uint8_t r = rgb[3 * i]; uint8_t g = rgb[3 * i + 1]; uint8_t b = rgb[3 * i + 2]; destination[i++] = ((66*r + 129*g + 25*b) >> 8) + 16; } } } } 

 ... int v_r = *r; int v_g = *g; int v_b = *b; *y = ((lookup66[v_r] + lookup129[v_g] + lookup25[v_b]) >> 8) + 16; ... 

 void Bitmap2Yuv420p( boost::uint8_t *destination, boost::uint8_t *rgb, const int &width, const int &height ) { const size_t image_size = width * height; const size_t upos = image_size; const size_t vpos = upos + upos / 4; for( size_t i = 0; i < image_size; ++i ) { boost::uint8_t r = rgb[3*i ]; boost::uint8_t g = rgb[3*i+1]; boost::uint8_t b = rgb[3*i+2]; destination[i] = ( ( 66*r + 129*g + 25*b ) >> 8 ) + 16; if (!((i / width) % 2) && !(i % 2)) { destination[upos++] = ( ( -38*r + -74*g + 112*b ) >> 8) + 128; destination[vpos++] = ( ( 112*r + -94*g + -18*b ) >> 8) + 128; } } } 

 void Bitmap2Yuv420p( boost::uint8_t *destination, boost::uint8_t *rgb, const int &width, const int &height ) { const size_t image_size = width * height; boost::uint8_t *dst_y = destination; boost::uint8_t *dst_u = destination + image_size; boost::uint8_t *dst_v = destination + image_size + image_size/4; // Y plane for( size_t i = 0; i < image_size; ++i ) { *dst_y++ = ( ( 66*rgb[3*i] + 129*rgb[3*i+1] + 25*rgb[3*i+2] ) >> 8 ) + 16; } #if 1 // U plane for( size_t y=0; y> 8 ) + 128; } // V plane for( size_t y=0; y> 8 ) + 128; } #else // also try this version: // U+V planes for( size_t y=0; y> 8 ) + 128; *dst_v++ = ( ( 112*rgb[3*i] + -94*rgb[3*i+1] + -18*rgb[3*i+2] ) >> 8 ) + 128; } #endif } 

 r = rgb + 3 * i; g = rgb + 3 * i + 1; b = rgb + 3 * i + 2; 

 r = rgb + 3 * i; g = r + 1; b = g + 1;