北京理工大学数码相机性能评测试验一视觉分辨率及空间频率响应SFR测试

1、数码相机性能评测实验一视觉分辨率及空间频率响应（SFR）测试实验目的：1、理解数码相机视觉分辨率的定义及其度量单位。2、了解数码相机分辨率测试标准ISO12233以及GB/T 19953-2005数码相机 分辨率的测量，熟悉测试标板构成，掌握其使用方法。3、掌握数码相机视觉分辨率测试方法，能够通过目视判别数码相机的分辨率特 性。4、了解数码相机空间频率响应（SFR的测试原理，理解空间频率响应（SFR 曲线的含义。5、掌握数码相机空间频率响应（SFR的测试方法,能够通过 SFR曲线判别数 码相机的分辨率特性。实验要求：1、使用数码相机拍摄ISO12233标准分辨率靶板，要求连续拍摄三幅图。2、目

2、视判别数码相机的视觉分辨率，需分别判别水平、垂直、和斜 45度方向 的视觉分辨率（注意：若拍摄的靶板有效区域高度仅占据相机幅面高度的一 部分，需将目视判别结果乘以修正系数以得到真实的测量结果。修正系数=以像素为单位的相机幅面高度/以像素为单位的靶板有效区域高度）。3、使用Imatest软件测量数码相机空间频率响应（SFR曲线，需分别测量水 平及垂直方向的SFR并取MTF50 MTF20乍为测量结果，与视觉分辨率测 试结果进行比较。1、使用数码相机拍摄ISO12233标准分辨率靶板，要求连续拍摄三幅图 第一张图第二张图QA-72-PRM第三张图6 7 flu 0146 8。T 121 一二二B

3、&伯母14 I-二二二-IT8-r6二三=1I<B1=VVV4-I;T1 2 3 4 5 G 7 a 9 O-1:.718 电二二 b 7 0 92、目视判别数码相机的视觉分辨率，需分别判别水平、垂直、和斜 45度方向的视觉分辨率第一张图的截图：水平条测中心垂直视觉分辨率对角线条测斜向上450视觉分辨率第二张图的截图:竖直条测中心水平分辨率4 12 10 8水平条测中心垂直视觉分辨率12对角线条测斜向上450视觉分辨率相机型号iPhone5123平均值水平方向视觉分辨率1450128013301320垂直方向视觉分辨率1240122012601240斜向上450视觉分辨率>

4、900>900>900>900实验人员实验日期2014.11.17骐围机 照相机窗膻商 电相机型号 光圈值 喘母洞 工即速度 曝光补偿 焦距口 I 、产 IEJ 用求立图 则先模式 目标5崎 闪光灯模式 闪光m缠 35mm阵踞pple iFhone 5 f/2 4 1730 秒 ISO-50 0步骤 ，套案酶无闪光，强制23明确相机型号、相机基本设置。3、使用Imatest软件测量数码相机空间频率响应(SFR曲线，需分别测量水 平及垂直方向的SFR并取MTF50 MTF20乍为测量结果，与视觉分辨率测试结 果进行比较。过程由黑到白由白到黑次数1垂直 方向2垂直 方向3 水平

5、方向4水平 方向5垂直 方向6垂直 方向7水平 方向8水平 方向分辨率(LW/PH)10881172158515421265130412441151均值(LW/PH)1130156412851198第一次目视(LW/PH)1240145012401450实验运行结果依次如下:23-Nov-2014 17:31:27Edge profile: Horizontal-3264 x 2448 pixels (WxH)7.99 MpxlsIMG_2250.JPGtaoxpn pkrorp eadEIf aenn prorp ea3ELbTRFS-6Edge -6.85 degsImatest 4.0.

6、15 Image Sensor ，rif-ROI: 100x440 pixels 27% above ctr/-channel (YA27)Gamma = 0.5010-90% rise = 2.35 pixels=1042 per PHRGB rise = 2.38 2.35 2.28 pxlsRMS Edge roughness = 0.0745 pxlsChart contrast = 10Gamma (from chart) = 0.755Lt, dk lvls = 217.2, 38.2 Lt/dk = 5.68-4-2024Pixels (Horizontal)100.80.6MT

7、F50 = 0.222 Cy/Pxlxl0.40.2Nyquist fMTF: Horizontal w/NR0Purchase at wwFmOeEvaluation5ve rsftCT= 1088 LW/PHUndersharpening 29.2%00.8Edge angle = -6.85 degsEstm. chart contrast = 32.3Selected EXIF dataMTF50 = 0.222 Cy/Pxl |=1088 LW/PHI(RGB) = 0.22 0.222 0.23 Cy/P xlFrequency, Cycles/pixelIMG

8、2250.JPGEdge profTfe: Horizontal2014 弓都"Edge -6.83 degsY-channel (YA21)Gamma = 0.503264 x 2448 pixels (WxH)7.99 Mpxls-ROI: 100x238 pixels 21% above ctr10-90% rise = 2.09 pixels=1172 per PHRGB rise = 2.1 2.09 2.03 pxlsRMS Edge roughness = 0.0739 pxlsChart contrast = 10Gamma (from chart) = 0.75Lt

9、, dk lvls = 217.1, 38.6 Lt/dk = 5.62Imatest 4.0.15 Image Sensorrrr-4-20246810Pixels (Horizontal)IIILLI iMTF50 = 0.254 Cy/Pxl-= 1241 LW/PH(RGB)= 0.252 0.252 0.263 Cy/P xl- EvaluatiMT怦0VersiOP = 1241 LW/PH-、Undersharpening 24.7%MTF50 = 0.254 Cy/Pxl-, MTF20 = 0.423 Cy/Pxl一 Purchas't wwwnmae跟.oom.Ny

10、quist f-MTF: Horizontal w/NR_0.81ROI: 100x440 pixelsL R T B = 1680 1779 460 899imatestROI: 100x238 pixelsL R T B = 1664 1763 691 928Edge angle = -6.83 degsEstm. chart contrast = 31.6Selected EXIF dataIEdge profile: Vertical-4-20246810Pixels (Vertical)ROI: 363x87 pixelsL R T B = 1435 1797 13

11、70 1456IMG 2250.JPG23-Nov-2014 17:42:22Edge 6.14 degsImatest 4.0.15 Image Sensor3264 x 2448 pixels (WxH)7.99 Mpxls_Y-channel (YB9) Gamma = 0.50-ROI: 363x87 pixels9.3% below ctr10-90% rise = 1.59 pixels=1537 per PHRGB rise = 1.6 1.59 1.6 pxlsRMS Edge roughness = 0.0741 pxlsChart contrast = 10Gamma (f

12、rom chart) = 0.841Lt, dk lvls = 210.7, 30.4 Lt/dk = 6.93faenn p.f.orp e adE-60.20Edge angle = 6.14 degsEstm. chart contrast = 48Selected EXIF dataIMG 2250.JPGEdge profile: Vertical3264 x 2448 pixels (WxH) 7.99 Mpxls23-Nov-2014 17:45:1210-90% rise=1.66 pixelsImatest 4.0.15 Image Sensor trI*

13、i-ROI: 280x155 pixels 11% below -R of ctrY-channel (YBR11)Gamma = 0.50Edge 6.35 degs=1473 per PHRGB rise = 1.66 1.66 1.66 pxlsRMS Edge roughness = 0.0809 pxlsChart contrast = 10Gamma (from chart) = 0.848Lt, dk lvls = 212.1, 30.1 Lt/dk = 7.05MTF50 = 0.324 Cy/Pxl= 1585 LW/PH(RGB) = 0.325 0.323 0.325 C

14、y/P xlEvaluation5ve rs2or= 1585 LW/PH一Undersharpening 17.1%MTF50 = 0.324 Cy/PxlMTF20 = 0.479 Cy/PxlPurchase abwwwTFrotiNytes=t0(?om一Nyquist fMTF: Vertical w/NR一00.8Frequency, Cycles/pixelMTF50 = 0.315 Cy/Pxl、=1542 LW/PH"、(RGB) = 0.317 0.313 0.316 Cy/P xl-'Evaluatio汴0vergionr= 1542

15、LW/PHUndersharpening 18.0% MTF50 = 0.315 Cy/PxlMTF20 = 0.476Cy/Pxl-Purchase atwvFanatetst. 1>om、Nyquist fMTF: Vertical w/NR0.8。imatestIMG_2250.JPGEdge profile: Horizontal-3264 x 2448 pixels (WxH)7.99 Mpxls23-Nov-2014 17:23:46xlraenn ArkTOTP eoaE-ROI: 169x294 pixels22% above ctr_Y-channel

16、 (YA22)Gamma = 0.50Edge -6.61 degs10-90% rise = 2.10 pixels=1168 per PHRGB rise = 2.21 2.11 1.84 pxlsRMS Edge roughness = 0.0845 pxlsChart contrast = 10Gamma (from chart) = 0.743Lt, dk lvls = 217.3, 39.3 Lt/dk = 5.53Imatest 4.0.15 Image SensorIIFROI: 169x294 pixelsL R T B = 1533 1701 636 929-6-4-210

17、0.8Pixels (Horizontal)MTF50 = 0.266 Cy/Pxl=1304 LW/PH(RGB)= 0.264 0.266 0.277 Cy/P xlEdge angle = -6.61 degsEstm. chart contrast = 30.6Selected EXIF dataLrTRFSEvaluatMTFFV eftC/P= 1304 LW/PHUndersharpening 24.6%MTF50 = 0.266 Cy/PxlMTF20 = 0.421 Cy/PxlPurchaseat wwwdmauestcomMTF: Horizontal

18、w/NR0.20.4Nyquist f0.60.8Frequency, Cycles/pixel。imatestIMG_2250.JPGEdge profile: Horizontal23-Nov-2014 17:26:05faenn prkTOTP eadE-3264 x 2448 pixels (WxH)7.99 MpxlsY-channel (YA23)Gamma = 0.50Edge -6.6 degs-ROI: 126x418 pixels 23% above ctr10-90% rise = 2.21 pixels=1108 per PHRGB rise = 2.32 2.21 1

19、.94 pxlsRMS Edge roughness = 0.083 pxlsChart contrast = 10Gamma (from chart) = 0.752Lt, dk lvls = 217.2, 38.5 Lt/dk = 5.65-6-4-20Imatest 4.0.15 Image SensorIIF6810LbTMVRFSPixels (Horizontal)0.2Nyquist fMTF: Horizontal w/NRMTF50 = 0.258 Cy/Pxl=1265 LW/PH(RGB) = 0.256 0.258 0.267 Cy/P xlEval

20、uatiorv e恃kC/P= 1265 LW/PHUndersharpening 25.6%0.8Edge angle = -6.6 degsEstm. chart contrast = 31.9Selected EXIF dataMTF50 = 0.258 Cy/PxlMTF20 = 0.407 Cy/PxlPurchasdat wwwdmaetst&QmROI: 126x418 pixelsL R T B = 1558 1683 537 954Edge profile: VerticalIMG_2250.JPGp3264 x 2448 pixels (WxH)7

21、.99 MpxlsLt, dk lvls = 210.1, 30.4 Lt/dk = 6.91Imatest 4.0.15 Image Sensor23-Nov-2014 17:47:11ROI: 216x117 pixels 15% below ctrY-channel (YB15)Gamma = 0.50Edge 5.91 degs10-90% rise = 2.04 pixels=1202 per PHRGB rise = 2.09 2.03 2.08 pxlsRMS Edge roughness = 0.0779 pxlsChart contrast = 10Gamma (from c

22、hart) = 0.84-6-4-20246810Pixels (Vertical)ROI: 216x117 pixelsL R T B = 1415 1630 1443 1559MTF50 = 0.254 Cy/Pxl=1244 LW/PH(RGB) = 0.252 0.252 0.268 Cy/P xlEdge angle = 5.91 degsEstm. chart contrast = 47.8Selected EXIF data EvaluatiOTTVe rs50CT= 1244 LW/PHUndersharpening 23.2%MTF50 = 0.254 Cy/Pxl0.2MTF20 = 0.408 Cy/P,Purchas*t wwwTFmNxlNyquist fMTF: Vertical w/NRL=00Frequency, Cycles/pixel_L0.81。imatestIMG 2250.JPG3264 x