Universality of Modified Pattern Decomposition Method for Satellite Sensors

Transcription

1 Unierality of Moifie Pattern Decompoition Metho for Satellite Senor Lifu Zhang *, Yauko Mituhita **, Shinobu Furumi **, Kanako Muramatu **, Noboru Fujiara **, Motomaa Daigo *** an Liangpei Zhang * * National Key Laboratory for Information Engineering in Sureying, Mapping, an Remote Sening, Wuhan Unierity, 19 Luoyu Roa, Wuhan , P. R. China ** Laboratory of Nature Information Science, Department of Information an Computer Science, Nara Women' Unierity, Nara, Japan *** Department of Economic, Dohiha Unierity, Kyoto, Japan ABSTRACT Many kin of atellite enor are aailable for analyzing lan coer or net primary prouction. Unfortunately, the reult epen on enor performance an epecially on the number of ban an the aelength obere, inter-enor comparion are ifficult. The pattern ecompoition metho (PDM) i a type of pectral mixing analyi in hich each pixel i expree a the linear um of fixe three tanar pectral pattern: ater, egetation an oil, ith upplementary pattern, inclue hen neceary. Thee tanar pattern are calculate from the ame original reflectance pectra by each enor. The ame frameork can be ue to apply PDM to any optical enor. Hoeer, een though tanar pattern for n-ban are prepare for each enor, pattern ecompoition coefficient obtaine iffer for each enor, een for the ample object. In thi paper, a moifie PDM i eelope a a unieral metho of analyi. By thi metho, the fixe multi-ban (9 ban) pectra (four ector in 9-imenional pace) are ue for any enor a the unieral tanar pectral pattern. The reulting pattern ecompoition coefficient ho unierality. Etimation error for pattern ecompoition coefficient epen on the enor. Namely, the etimation error for Lanat/MSS an ALOS/AVNIR- are larger than thoe Terra/MODIS or ADEOS-II/GLI. KEY WORDS: RS, Hyper-Multi-pectral RS, Unieral PDM 1

2 1 INTRODUCTION There are many kin of atellite enor for lan analyi. Recent atellite enor uch a Terra/MODIS an ADEOS-II/GLI proie hyper-multi-pectral ata. Unfortunately, the reult of analyi epen on the performance of the enor, epecially the number of ban an aelength obere. It i thu ifficult to make unieral comparion of analyi mae by ifferent atellite enor. One unieralizing metho employ the traitional normalize ifferential egetation inex (NDVI), but it ue reflectance ata from only re an near infrare aelength (Nemani et. al., 1993). The pattern ecompoition metho (PDM) allo for effectie ue of multi-pectral ata (Fujiara et. al., 1996; Muramatu et. al., 000). The PDM i a type of pectral mixing analyi (Aam et. al., 1995) that expree each pixel a the linear um of three fixe tanar pectral pattern: ater, egetation an oil. The three pattern are gien a nearly orthogonal ector in multiimenional pace, an are extracte from the ame common pectra meaure on the groun. Uing the ame frameork, the PDM can be applicable to any enor. In thi paper, e expan the PDM to eelop a unieral metho of analyi, namely, to obtain pattern ecompoition coefficient of enor inepenent. ANALYSIS METHOD.1 The unieral pattern ecompoition metho In the PDM, the et of reflectance (or brightne) ata for each pixel obere by a enor i ecompoe into the three tanar pectral pattern of ater, egetation an oil. If neceary for more etaile analyi, a upplementary tanar pectral pattern can be ue. The formulation i a follo (Daigo et al., 003): A( i) C P ( i), (1) here A(i) i the reflectance of ban i, an P(i), P (i) an P (i) are the tanar pectral pattern of ater, egetation an oil. P (i) i a upplementary pectral pattern. The reiual of the i ban' reflectance i efine a follo: R( i) = A( i) { C P ( i) }. () The ample ue for the tanar pectral pattern are ocean ater, oerlapping leae an ry an. The upplementary pattern i obtaine from reiual R(i) of Equation () for a yello leaf. The tanar pectral pattern are normalize a: N P ( i) = 1, ( k,,, ). (3) i k = Where N i the number of ban of a enor, the ecompoition coefficient C, C, C an the

3 coefficient for the upplementary pattern C are ealuate uing the leat quare metho. In thi PDM, the tanar pattern epen on the ban aelength etecte by the enor an on the number of ban, een though the ame continuou pectra ere a the tanar pectra. A a reult, the alue of the pattern ecompoition coefficient for the ame object epen on the enor. We hae eelope a ne unieral PDM in hich the pattern ecompoition coefficient in the ame four-imenional pace of C, C, C an C are obtaine. In principle, in a enor inepenent metho, nearly ientical alue are obtaine for ata from the ame object, regarle of the enor. We efine tanar pectral pattern a a continuou pectral function an intea of Equation (3), normalize a follo: P k ( x) x = [ nm], ( k =,,, ) (4) here x i aelength [nm] an i ith of integrate aelength. That i, (x) i efine a the aerage alue of P k (x), hich equal one. The pectral pattern of (x) a a function of x are the ame a the pectral pattern of reflectance from tanar object. A olar light i ue, the pectral region ue for analyi i retricte to area here the atmopheric tranmittance i higher than 80%. Other aelength region are exclue from Equation (4). Table 1 ho the aelength region ue for tanar pectral pattern. Table 1 Waelength region ue in thi analyi ~ nm ~ nm ~ nm ~ nm ~ nm P k P k The (i) P k for each enor in Equation (1) i efine a follo: Pk ( i) = [ f ( i) P k ( i) i ( x) x]/{ f ( i) ( i)}, (5) here { f ( i) i ( i)} i aelength ith of ban i of a enor. The P k (i) i the alue P k (i) at aerage aelength x of ban i. The reflectance A(i) in Equation (1) i reefine a follo: A( i) A(i). (6) The pattern ecompoition coefficient of Equation (1) are ealuate uing the leat quare metho. The obtaine coefficient are alue in the ame four-imenional i (k=1,,3,4) pace. In principle, for atum from the ame object, almot the ame alue are expecte for all enor. In C k 3

4 practice, the preciion of the coefficient improe a the number of ban increae. The fitte reflectance i the alue of the right ie of Equation (1) iie by reuce χ are efine a follo for a enor of number of ban:. The χ = r ( i) /( n 4). (7) i here r (i) = R(i) / an ( n 4) repreent the egree of freeom for a ataet of n-ban.. Stanar pectral pattern an ample ata The ample ata ue in thi analyi ere meaure outoor uner olar light or inoor uner a halogen lamp ith a Fiel Spec FR (Analytical Spectral Deice Inc.) or MSR7000 (Opto Reearch Corp.) raio-pectrometer. Both raio-pectrometer gie ra pectral alue eery 1 nm for aelength of 350 nm to,500 nm. Spectral reolution rage from 3 to 10 nm. The ample ue for tanar pectral pattern ere the ame a thoe ue for reference (Daigo et. al., 003). Figure 1 ho the ne normalize tanar pectral pattern of ater (blue +), egetation (green ), oil (re ) an the upplement (purple ). A mentione in Section, the pectral region ue for analyi a retricte to here the atmopheric tranmittance a higher than 80%. Figure 1. Normalize tanar pattern of oil, ater, egetation an the upplementary pattern..3 Senor an ample ata ue for analyi The tet enor (number of ban) ue for thi analyi ere MSS, ALOS, TM, MODIS an 4

5 GLI. In aition to thee enor, the moel enor MODEL an CONTINUE (9 ban) ere alo ue. Ban in hich output ignal from the enor (MODIS & GLI) ere aturate on lan area ere remoe. In the aelength region aboe,000 nm, groun-meaure ata are of poor quality, thee ata ere alo remoe from thi analyi. For each ban of each enor, aerage reflectance alue ere obtaine from groun-meaure ata ithin aelength ith of each ban of the enor. Table lit the ban ue in thi analyi. The moel enor CONTINUE ha 9 ban from aelength of 371 nm to 1,750 nm a hon in Table 1 ith ban ith of 10 nm. Table Spectral ban ue in thi analyi MSS (4 ban) ALOS (4 ban) ETM+(5 ban) MODIS (6 ban) ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 1, ~ ~ ~ ,549.5 ~ 1, ,30.0 ~ 1,50.0 1,68.0 ~ 1,65.0 GLI (10 ban) ~ ~ ~ ,040.0 ~1, ~ ,30.0 ~1, ~ ,540.0 ~1, ~ ~767.0 MODEL (1 ban) ~ ~ ~ ~ 1, ~ ,040.0 ~ 1, ~ ,00.0 ~ 1, ~ ,540.0 ~ 1, ~ ,650.0 ~ 1, RESULTS AND DISCUSSION 3.1 Reproucibility of obere pectra ith unieral PDM an reuce χ Figure ho typical original reflectance pectra meaure on the groun an the recontructe reflectance pectra of 9 ban full pectra calculate by the pattern ecompoition coefficient obtaine for each enor. In the Figure, re rhombue ho original meaure ata. The blue broken line, green broken line an purple croe repreent recontructe pectra for the ALOS, GLI an CONTINUE enor. The original pectra are reprouce ell except thoe from ALOS. The recontructe pectra for TM, MODIS an MODEL are nearly the ame a the pectra for GLI an 5

6 CONYINUE. The recontructe pectra for MSS are not hon in the figure. The ata point correponing to aelength of the MSS ban (499.5~1,100.5 nm) are exactly reprouce. Hoeer, epecially aboe aelength of 1,000 nm, the reprouce alue iffer completely from the original ata. Figure. The original reflectance pectra an recontructe reflectance pectra Figure 3. Reuce χ for recontructe pectra 6

7 Becaue e hae four fitting parameter C, C, C an C, the fitting error for the four- ban enor (MSS an ALOS) are zero. Figure 3 ho catter plot of the reuce χ for the unieral PDM a a function of the enor. The number of ample i about 1,300. The alue ecreae accoring to increae in the ban number an conerge at for ban number larger than fie (TM). Table 3 lit the aerage alue of the reuce χ for each enor are lite in Table 3. The quare root of i (1.8%) an i the fitting error per egree of freeom. Table 3 The aerage alue of reuce χ MSS ALOS ETM MODIS GLI MODEL CONTINUE Correlating the pattern ecompoition coefficient ith the unieral PDM Figure 4. Correlation of unieral pattern ecompoition coefficient 7

8 Figure 4 ho the correlation of the PDM coefficient ith the unieral pattern ecompoition metho. The x-axi ho the PDM coefficient for continuou pectra, an the y-axi ho ETM, MODIS, GLI or MODEL enor. A expecte, the coefficient obtaine for each enor are nearly equal to the coefficient obtaine from the continuou pectra. Thi mean that the coefficient of the unieral PDM are enor-inepenent alue. 4 SUMMARY AND CONCLUSIONS We eelope a unieral pattern ecompoition metho to obtain enor-inepenent pattern ecompoition coefficient for reflectance ata in the 371nm to 1,750nm aelength range. We erifie that the pattern ecompoition coefficient obtaine are almot enor inepenent, except for four-ban enor uch a MSS an ALOS. Uing thi metho, e can enor-inepenently analyze atellite ata an compare analyi reult for lan uner conition that effectiely reflect multipectral ata. ACKNOWLEDGEMENTS Thi ork a upporte uner the ADEOS-II/GLI project by the National Space Deelopment Agency of Japan (NASDA). REFERENCES Nemani,R., Pierce, L., Running, S., an Ban, L. (1993). Foret ecoytem procee at the aterhe cale: enitiity to remotely-ene leaf area inex etimate, International Journal of Remote Sening, 14, 519. Aam, J. B., Sabol, D. E., Kapo, V, Filho, R. A., Robert, D. A., Smith, M. O., an Gillepie, A. R. (1995). Claification of multipectral image bae on fraction of enmember: application to lan coer change in the Brazilian Amazon, Remote Sening of Enironment, 5, Daigo, M., Ono, A., Fujiara, N, an Urabe, R. (003). Pattern ecompoition metho for hypermulti-pectral ata analyi, in printe in International Journal of Remote Sening Fujiara, N., Muramatu, K., Aa, S., Hazumi, A. an Ochiai, F. (1996). Pattern expanion metho for atellite ata analyi, (in Japanee). Journal of Remote Sening Society of Japan, 17(3), Muramatu, K., Furumi, S., Fujiara, N., Hayahi, A., Daigo, M., an Ochiai, F. (000). Pattern ecompoition metho in the albeo pace for Lanat TM an MSS ata analyi, International Journal of Remote Sening, 1(1),