在java imageIO中，压缩质量和图像文件大小之间是否存在任何关系？

我有一个java代码，基本上使用java中的ImageIO压缩图像。当我设置压缩质量的值时，无论图像大小如何，我都必须对其进行硬编码。我想要实现的是，对于较大尺寸的图像，我希望压缩质量因子较低，对于较小尺寸的图像，我希望压缩质量因子较高

我有什么办法可以做到这一点吗？ 更具体地说，我想要的是 图像大小-12MB，压缩质量因子-0.05 图像大小-2MB，压缩质量-0.5

我希望动态地设置它，以便生成的图像大小始终在一定的范围内，比如300到450KB

对于不同的压缩和不同文件大小的图像，我得到了不同的图像值。这是我得到的曲线

相应的Python代码将解释数据点（compressionQuality、CompressionDimageSize）和inputImageSize

param.setCompressionQuality(0.05f);

---

我现在如何获得这些数据点的一般曲线。

我建议您在不同的图像上测试不同的质量因子，以查看两个值之间的关系，例如使用图表；然后试着找出一个函数，它是给定质量因子的大小的一个很好的近似值。是的，这是有意义的。我会试试看的。@MauricePerry，你知道我现在该如何前进吗？我会尝试匹配指数。说

compressedSize=uncompressedSize*[exp（a*r+b）-1]

。其中a和b是函数的参数。uncompressedSize=3*width*height。3*height*width是什么意思？我建议您在不同的图像上测试不同的质量因子，以查看这两个值之间的关系，例如使用图表；然后试着找出一个函数，它是给定质量因子的大小的一个很好的近似值。是的，这是有意义的。我会试试看的。@MauricePerry，你知道我现在该如何前进吗？我会尝试匹配指数。说

compressedSize=uncompressedSize*[exp（a*r+b）-1]

。其中a和b是函数的参数。解压大小=3*宽*高。3*高*宽是什么意思？

import matplotlib.pyplot as plt
#
# File Size = 19.910137176513672MB Image 15
a = 19.91
Y1 = [22.679447174072266,19.149768829345703,15.593475341796875,13.593769073486328,11.73095989227295,10.280043601989746,9.200546264648438,8.24983024597168,7.478874206542969,7.081890106201172,6.649069786071777,6.139764785766602,5.877098083496094,5.498229026794434,5.291265487670898,4.999222755432129,4.8131303787231445,4.632769584655762,4.401802062988281,4.254202842712402,4.0784149169921875,3.9381275177001953,3.848017692565918,3.711637496948242,3.554410934448242,3.4564571380615234,3.437223434448242,3.3112993240356445,3.2114038467407227,3.1557493209838867,3.083315849304199,3.0021963119506836,2.9427528381347656,2.858595848083496,2.813009262084961,2.7678117752075195,2.6995487213134766,2.66660213470459,2.605208396911621,2.573880195617676,2.514714241027832,2.4811811447143555,2.4574146270751953,2.407167434692383,2.3616294860839844,2.323910713195801,2.2925004959106445,2.2733144760131836,2.2356204986572266,2.179229736328125,2.173373222351074,2.1678152084350586,2.1029653549194336,2.079085350036621,2.063828468322754,2.0330677032470703,1.9996404647827148,1.9659032821655273,1.9462108612060547,1.9092254638671875,1.8746976852416992,1.8544721603393555,1.829930305480957,1.7931203842163086,1.7694215774536133,1.7388124465942383,1.702286720275879,1.6824798583984375,1.6441326141357422,1.6178398132324219,1.5875110626220703,1.557560920715332,1.5282955169677734,1.4977445602416992,1.4657106399536133,1.4351539611816406,1.4044828414916992,1.3735761642456055,1.3403663635253906,1.3088655471801758,1.2744388580322266,1.2435684204101562,1.211979866027832,1.1799592971801758,1.1425504684448242,1.1092376708984375,1.0737104415893555,1.038456916809082,1.000680923461914,0.9624481201171875,0.9242935180664062,0.8840703964233398,0.8429794311523438,0.8006277084350586,0.7578287124633789,0.712580680847168,0.6670083999633789,0.6259841918945312,0.606475830078125,0.6063032150268555,]
X1 = [1.0,0.99,0.98,0.97,0.96,0.95,0.94,0.9299999999999999,0.9199999999999999,0.9099999999999999,0.8999999999999999,0.8899999999999999,0.8799999999999999,0.8699999999999999,0.8599999999999999,0.8499999999999999,0.8399999999999999,0.8299999999999998,0.8199999999999998,0.8099999999999998,0.7999999999999998,0.7899999999999998,0.7799999999999998,0.7699999999999998,0.7599999999999998,0.7499999999999998,0.7399999999999998,0.7299999999999998,0.7199999999999998,0.7099999999999997,0.6999999999999997,0.6899999999999997,0.6799999999999997,0.6699999999999997,0.6599999999999997,0.6499999999999997,0.6399999999999997,0.6299999999999997,0.6199999999999997,0.6099999999999997,0.5999999999999996,0.5899999999999996,0.5799999999999996,0.5699999999999996,0.5599999999999996,0.5499999999999996,0.5399999999999996,0.5299999999999996,0.5199999999999996,0.5099999999999996,0.49999999999999956,0.48999999999999955,0.47999999999999954,0.46999999999999953,0.4599999999999995,0.4499999999999995,0.4399999999999995,0.4299999999999995,0.4199999999999995,0.4099999999999995,0.39999999999999947,0.38999999999999946,0.37999999999999945,0.36999999999999944,0.35999999999999943,0.3499999999999994,0.3399999999999994,0.3299999999999994,0.3199999999999994,0.3099999999999994,0.2999999999999994,0.28999999999999937,0.27999999999999936,0.26999999999999935,0.25999999999999934,0.24999999999999933,0.23999999999999932,0.22999999999999932,0.2199999999999993,0.2099999999999993,0.1999999999999993,0.18999999999999928,0.17999999999999927,0.16999999999999926,0.15999999999999925,0.14999999999999925,0.13999999999999924,0.12999999999999923,0.11999999999999923,0.10999999999999924,0.09999999999999924,0.08999999999999925,0.07999999999999925,0.06999999999999926,0.059999999999999255,0.04999999999999925,0.03999999999999925,0.02999999999999925,0.019999999999999248,0.009999999999999247,]
#File Size: 16.06 MB Image 12
b = 16.06
Y2 = [16.67084312438965,14.76289176940918,12.559616088867188,11.151044845581055,9.831572532653809,8.824997901916504,7.965936660766602,7.252984046936035,6.697719573974609,6.370810508728027,6.048678398132324,5.688633918762207,5.464935302734375,5.176077842712402,5.033934593200684,4.796394348144531,4.640280723571777,4.502942085266113,4.3267107009887695,4.203361511230469,4.059324264526367,3.9404945373535156,3.8596086502075195,3.7588043212890625,3.622213363647461,3.537647247314453,3.5118370056152344,3.400078773498535,3.324885368347168,3.2690792083740234,3.204397201538086,3.1241350173950195,3.076218605041504,2.9987001419067383,2.953375816345215,2.9116554260253906,2.8495607376098633,2.818735122680664,2.760129928588867,2.72426700592041,2.6722984313964844,2.6385087966918945,2.6137638092041016,2.5618724822998047,2.520803451538086,2.4810352325439453,2.450857162475586,2.4265098571777344,2.392702102661133,2.3383007049560547,2.3292531967163086,2.3210792541503906,2.2553958892822266,2.228961944580078,2.2134809494018555,2.1789979934692383,2.1453332901000977,2.109243392944336,2.082709312438965,2.0474157333374023,2.008913993835449,1.984980583190918,1.9581937789916992,1.9168310165405273,1.8906946182250977,1.8563108444213867,1.8126325607299805,1.789398193359375,1.7446098327636719,1.7110843658447266,1.6768722534179688,1.6425094604492188,1.6053228378295898,1.5692682266235352,1.5310239791870117,1.4951438903808594,1.4564857482910156,1.4185314178466797,1.376399040222168,1.3394126892089844,1.2957754135131836,1.2571725845336914,1.2160987854003906,1.1765003204345703,1.129739761352539,1.0880403518676758,1.0438518524169922,0.9999103546142578,0.9522476196289062,0.9046707153320312,0.8571853637695312,0.8070306777954102,0.7559423446655273,0.7047004699707031,0.6505136489868164,0.5932273864746094,0.536219596862793,0.48065185546875,0.4509124755859375,0.45049095153808594,]
X2 = [1.0,0.99,0.98,0.97,0.96,0.95,0.94,0.9299999999999999,0.9199999999999999,0.9099999999999999,0.8999999999999999,0.8899999999999999,0.8799999999999999,0.8699999999999999,0.8599999999999999,0.8499999999999999,0.8399999999999999,0.8299999999999998,0.8199999999999998,0.8099999999999998,0.7999999999999998,0.7899999999999998,0.7799999999999998,0.7699999999999998,0.7599999999999998,0.7499999999999998,0.7399999999999998,0.7299999999999998,0.7199999999999998,0.7099999999999997,0.6999999999999997,0.6899999999999997,0.6799999999999997,0.6699999999999997,0.6599999999999997,0.6499999999999997,0.6399999999999997,0.6299999999999997,0.6199999999999997,0.6099999999999997,0.5999999999999996,0.5899999999999996,0.5799999999999996,0.5699999999999996,0.5599999999999996,0.5499999999999996,0.5399999999999996,0.5299999999999996,0.5199999999999996,0.5099999999999996,0.49999999999999956,0.48999999999999955,0.47999999999999954,0.46999999999999953,0.4599999999999995,0.4499999999999995,0.4399999999999995,0.4299999999999995,0.4199999999999995,0.4099999999999995,0.39999999999999947,0.38999999999999946,0.37999999999999945,0.36999999999999944,0.35999999999999943,0.3499999999999994,0.3399999999999994,0.3299999999999994,0.3199999999999994,0.3099999999999994,0.2999999999999994,0.28999999999999937,0.27999999999999936,0.26999999999999935,0.25999999999999934,0.24999999999999933,0.23999999999999932,0.22999999999999932,0.2199999999999993,0.2099999999999993,0.1999999999999993,0.18999999999999928,0.17999999999999927,0.16999999999999926,0.15999999999999925,0.14999999999999925,0.13999999999999924,0.12999999999999923,0.11999999999999923,0.10999999999999924,0.09999999999999924,0.08999999999999925,0.07999999999999925,0.06999999999999926,0.059999999999999255,0.04999999999999925,0.03999999999999925,0.02999999999999925,0.019999999999999248,0.009999999999999247,]

# File Size = 14.51 MB Image 14.
c = 14.51
Y3 = [13.276880264282227,11.054244041442871,9.290040969848633,8.079867362976074,7.136639595031738,6.357952117919922,5.730681419372559,5.230585098266602,4.7916460037231445,4.614978790283203,4.396919250488281,4.112512588500977,3.9680347442626953,3.7767181396484375,3.664793014526367,3.482412338256836,3.39394474029541,3.29836368560791,3.1423254013061523,3.0661697387695312,2.9582481384277344,2.8713035583496094,2.8210067749023438,2.7330942153930664,2.625102996826172,2.5610103607177734,2.5580825805664062,2.469636917114258,2.4008283615112305,2.3688669204711914,2.3211278915405273,2.260828971862793,2.227842330932617,2.1547956466674805,2.125030517578125,2.0986194610595703,2.049541473388672,2.0267295837402344,1.9801397323608398,1.9601554870605469,1.9158334732055664,1.8920927047729492,1.8745508193969727,1.8349456787109375,1.8008337020874023,1.7698888778686523,1.7466506958007812,1.7369518280029297,1.705923080444336,1.6592397689819336,1.658132553100586,1.6573419570922852,1.5991802215576172,1.580143928527832,1.5716381072998047,1.5483465194702148,1.5208559036254883,1.4949846267700195,1.4799222946166992,1.4486818313598633,1.420851707458496,1.4039602279663086,1.3871431350708008,1.3538141250610352,1.3360700607299805,1.3108997344970703,1.2779560089111328,1.2646903991699219,1.2326793670654297,1.2113447189331055,1.1856470108032227,1.1611948013305664,1.1375789642333984,1.112492561340332,1.0855484008789062,1.062150001525879,1.0349740982055664,1.0107431411743164,0.9834566116333008,0.9569740295410156,0.9299612045288086,0.9054183959960938,0.8805217742919922,0.8559408187866211,0.826171875,0.8007307052612305,0.7740201950073242,0.7483835220336914,0.7205448150634766,0.6930246353149414,0.666682243347168,0.6389961242675781,0.6115951538085938,0.5838098526000977,0.5555095672607422,0.5264978408813477,0.4979524612426758,0.47070789337158203,0.4587059020996094,0.45865345001220703,]
X3 = [1.0,0.99,0.98,0.97,0.96,0.95,0.94,0.9299999999999999,0.9199999999999999,0.9099999999999999,0.8999999999999999,0.8899999999999999,0.8799999999999999,0.8699999999999999,0.8599999999999999,0.8499999999999999,0.8399999999999999,0.8299999999999998,0.8199999999999998,0.8099999999999998,0.7999999999999998,0.7899999999999998,0.7799999999999998,0.7699999999999998,0.7599999999999998,0.7499999999999998,0.7399999999999998,0.7299999999999998,0.7199999999999998,0.7099999999999997,0.6999999999999997,0.6899999999999997,0.6799999999999997,0.6699999999999997,0.6599999999999997,0.6499999999999997,0.6399999999999997,0.6299999999999997,0.6199999999999997,0.6099999999999997,0.5999999999999996,0.5899999999999996,0.5799999999999996,0.5699999999999996,0.5599999999999996,0.5499999999999996,0.5399999999999996,0.5299999999999996,0.5199999999999996,0.5099999999999996,0.49999999999999956,0.48999999999999955,0.47999999999999954,0.46999999999999953,0.4599999999999995,0.4499999999999995,0.4399999999999995,0.4299999999999995,0.4199999999999995,0.4099999999999995,0.39999999999999947,0.38999999999999946,0.37999999999999945,0.36999999999999944,0.35999999999999943,0.3499999999999994,0.3399999999999994,0.3299999999999994,0.3199999999999994,0.3099999999999994,0.2999999999999994,0.28999999999999937,0.27999999999999936,0.26999999999999935,0.25999999999999934,0.24999999999999933,0.23999999999999932,0.22999999999999932,0.2199999999999993,0.2099999999999993,0.1999999999999993,0.18999999999999928,0.17999999999999927,0.16999999999999926,0.15999999999999925,0.14999999999999925,0.13999999999999924,0.12999999999999923,0.11999999999999923,0.10999999999999924,0.09999999999999924,0.08999999999999925,0.07999999999999925,0.06999999999999926,0.059999999999999255,0.04999999999999925,0.03999999999999925,0.02999999999999925,0.019999999999999248,0.009999999999999247,]


# File Size = 12.182676315307617 MB Image 16
d = 12.18
Y4 = [13.01069450378418,11.495155334472656,9.535579681396484,8.453946113586426,7.453679084777832,6.675678253173828,6.071930885314941,5.505851745605469,5.084687232971191,4.813249588012695,4.553813934326172,4.251683235168457,4.071293830871582,3.838838577270508,3.7037839889526367,3.5256881713867188,3.382601737976074,3.263218879699707,3.128805160522461,3.026984214782715,2.9083681106567383,2.8078250885009766,2.738035202026367,2.6553544998168945,2.550203323364258,2.4743833541870117,2.449167251586914,2.359891891479492,2.299839973449707,2.2536754608154297,2.199315071105957,2.1356077194213867,2.093381881713867,2.0358171463012695,1.9979190826416016,1.9607172012329102,1.911966323852539,1.8838367462158203,1.8384265899658203,1.8107585906982422,1.768341064453125,1.7384967803955078,1.718912124633789,1.6787662506103516,1.646352767944336,1.6144895553588867,1.5885858535766602,1.5683221817016602,1.5433597564697266,1.4981613159179688,1.490304946899414,1.4830093383789062,1.4328117370605469,1.4126787185668945,1.3976774215698242,1.371260643005371,1.3448619842529297,1.3149194717407227,1.2957782745361328,1.2667303085327148,1.236496925354004,1.218388557434082,1.196486473083496,1.1649198532104492,1.1443729400634766,1.1181116104125977,1.0859012603759766,1.067173957824707,1.033905029296875,1.0101556777954102,0.9834413528442383,0.9582509994506836,0.9324407577514648,0.905792236328125,0.8786830902099609,0.8526592254638672,0.8271675109863281,0.8010168075561523,0.7733821868896484,0.7484416961669922,0.7208003997802734,0.6966991424560547,0.6719264984130859,0.6475048065185547,0.6195907592773438,0.5949335098266602,0.5689992904663086,0.5438718795776367,0.5170812606811523,0.49069976806640625,0.4643869400024414,0.4366168975830078,0.40883350372314453,0.3811054229736328,0.35283946990966797,0.3242063522338867,0.2960548400878906,0.2710552215576172,0.25942134857177734,0.2593259811401367,]
X4 = [1.0,0.99,0.98,0.97,0.96,0.95,0.94,0.9299999999999999,0.9199999999999999,0.9099999999999999,0.8999999999999999,0.8899999999999999,0.8799999999999999,0.8699999999999999,0.8599999999999999,0.8499999999999999,0.8399999999999999,0.8299999999999998,0.8199999999999998,0.8099999999999998,0.7999999999999998,0.7899999999999998,0.7799999999999998,0.7699999999999998,0.7599999999999998,0.7499999999999998,0.7399999999999998,0.7299999999999998,0.7199999999999998,0.7099999999999997,0.6999999999999997,0.6899999999999997,0.6799999999999997,0.6699999999999997,0.6599999999999997,0.6499999999999997,0.6399999999999997,0.6299999999999997,0.6199999999999997,0.6099999999999997,0.5999999999999996,0.5899999999999996,0.5799999999999996,0.5699999999999996,0.5599999999999996,0.5499999999999996,0.5399999999999996,0.5299999999999996,0.5199999999999996,0.5099999999999996,0.49999999999999956,0.48999999999999955,0.47999999999999954,0.46999999999999953,0.4599999999999995,0.4499999999999995,0.4399999999999995,0.4299999999999995,0.4199999999999995,0.4099999999999995,0.39999999999999947,0.38999999999999946,0.37999999999999945,0.36999999999999944,0.35999999999999943,0.3499999999999994,0.3399999999999994,0.3299999999999994,0.3199999999999994,0.3099999999999994,0.2999999999999994,0.28999999999999937,0.27999999999999936,0.26999999999999935,0.25999999999999934,0.24999999999999933,0.23999999999999932,0.22999999999999932,0.2199999999999993,0.2099999999999993,0.1999999999999993,0.18999999999999928,0.17999999999999927,0.16999999999999926,0.15999999999999925,0.14999999999999925,0.13999999999999924,0.12999999999999923,0.11999999999999923,0.10999999999999924,0.09999999999999924,0.08999999999999925,0.07999999999999925,0.06999999999999926,0.059999999999999255,0.04999999999999925,0.03999999999999925,0.02999999999999925,0.019999999999999248,0.009999999999999247,]

#File Size: 4.24 MB. Image 13
e = 4.24
Y5 = [9.064751625061035,7.568966865539551,6.7567338943481445,6.300202369689941,5.916131019592285,5.440644264221191,4.797977447509766,4.443161964416504,4.242552757263184,4.159173011779785,4.093925476074219,3.951435089111328,3.8859710693359375,3.7636919021606445,3.7036514282226562,3.553114891052246,3.2596235275268555,2.8775529861450195,2.5981435775756836,2.4770002365112305,2.3274784088134766,2.257047653198242,2.230719566345215,2.179755210876465,2.137324333190918,2.1085643768310547,2.103451728820801,2.068082809448242,2.0240488052368164,2.011676788330078,1.979508399963379,1.9415597915649414,1.9103755950927734,1.8651809692382812,1.8359222412109375,1.804671287536621,1.7406959533691406,1.7213382720947266,1.6697349548339844,1.6623163223266602,1.616246223449707,1.6110877990722656,1.5874900817871094,1.5694646835327148,1.548872947692871,1.5079545974731445,1.4904956817626953,1.4748411178588867,1.4498329162597656,1.3852806091308594,1.3839998245239258,1.3830080032348633,1.3207406997680664,1.3091001510620117,1.2958669662475586,1.2680768966674805,1.2422723770141602,1.2158193588256836,1.2042760848999023,1.1871204376220703,1.1635704040527344,1.1545038223266602,1.1277284622192383,1.115091323852539,1.0861167907714844,1.0656414031982422,1.0310983657836914,1.0169944763183594,0.9900989532470703,0.9725027084350586,0.9511575698852539,0.9243431091308594,0.9005632400512695,0.8773460388183594,0.8538885116577148,0.8338842391967773,0.8117237091064453,0.7969913482666016,0.7757482528686523,0.7456951141357422,0.7246723175048828,0.6977834701538086,0.676081657409668,0.6542282104492188,0.6292667388916016,0.607391357421875,0.5807857513427734,0.554783821105957,0.529362678527832,0.5039873123168945,0.47869396209716797,0.4519176483154297,0.42555904388427734,0.3984832763671875,0.3717536926269531,0.34433841705322266,0.3178243637084961,0.29532814025878906,0.28563880920410156,0.2856149673461914,]
X5 = [1.0,0.99,0.98,0.97,0.96,0.95,0.94,0.9299999999999999,0.9199999999999999,0.9099999999999999,0.8999999999999999,0.8899999999999999,0.8799999999999999,0.8699999999999999,0.8599999999999999,0.8499999999999999,0.8399999999999999,0.8299999999999998,0.8199999999999998,0.8099999999999998,0.7999999999999998,0.7899999999999998,0.7799999999999998,0.7699999999999998,0.7599999999999998,0.7499999999999998,0.7399999999999998,0.7299999999999998,0.7199999999999998,0.7099999999999997,0.6999999999999997,0.6899999999999997,0.6799999999999997,0.6699999999999997,0.6599999999999997,0.6499999999999997,0.6399999999999997,0.6299999999999997,0.6199999999999997,0.6099999999999997,0.5999999999999996,0.5899999999999996,0.5799999999999996,0.5699999999999996,0.5599999999999996,0.5499999999999996,0.5399999999999996,0.5299999999999996,0.5199999999999996,0.5099999999999996,0.49999999999999956,0.48999999999999955,0.47999999999999954,0.46999999999999953,0.4599999999999995,0.4499999999999995,0.4399999999999995,0.4299999999999995,0.4199999999999995,0.4099999999999995,0.39999999999999947,0.38999999999999946,0.37999999999999945,0.36999999999999944,0.35999999999999943,0.3499999999999994,0.3399999999999994,0.3299999999999994,0.3199999999999994,0.3099999999999994,0.2999999999999994,0.28999999999999937,0.27999999999999936,0.26999999999999935,0.25999999999999934,0.24999999999999933,0.23999999999999932,0.22999999999999932,0.2199999999999993,0.2099999999999993,0.1999999999999993,0.18999999999999928,0.17999999999999927,0.16999999999999926,0.15999999999999925,0.14999999999999925,0.13999999999999924,0.12999999999999923,0.11999999999999923,0.10999999999999924,0.09999999999999924,0.08999999999999925,0.07999999999999925,0.06999999999999926,0.059999999999999255,0.04999999999999925,0.03999999999999925,0.02999999999999925,0.019999999999999248,0.009999999999999247,]


plt.plot(X1, Y1, color='green', linestyle='dashed', linewidth = 3,
         marker='o', markerfacecolor='blue', markersize=8)

plt.plot(X2, Y2, color='green', linestyle='dashed', linewidth = 3,
         marker='o', markerfacecolor='red', markersize=8)

plt.plot(X3, Y3, color='green', linestyle='dashed', linewidth = 3,
         marker='o', markerfacecolor='cyan', markersize=8)

plt.plot(X4, Y4, color='green', linestyle='dashed', linewidth = 3,
         marker='o', markerfacecolor='magenta', markersize=8)

plt.plot(X5, Y5, color='green', linestyle='dashed', linewidth = 3,
         marker='o', markerfacecolor='yellow', markersize=8)


plt.xlabel('Compression - Quality - Factor')
plt.ylabel('Compressed - Image - Size')
plt.title('Quality Factor and size comparision')

plt.show()