Tuesday, 25 August 2009

ISO 9001:2008 Certification

We are happy to announce that Jurukur Perunding Services Sdn Bhd and Jurukur Perunding World Service Sdn Bhd are now jointly recertified by Sirim QAS International Sdn Bhd based upon the revised version of the Quality Management System Standards. The multi-site certification awarded to our Selangor-based headquarters and selected regional branches in Peninsular Malaysia is a unique achievement for a Malaysian land surveying company.
The demonstration of conformity to the requirements of ISO 9001:2008 is evidence of continual improvement in our provision of land cum hydrographic surveys and services relating to aerial mapping, Geographical Information Systems, remote sensing and geomatics to new and existing customers (or clients).
Credit shall be given to the various divisional General Managers, their QDCCs and staff. The management of the JPSurveys group of companies also appreciates the effort of the Quality Management Unit (QMU) regarding its certification endeavour since late 2002. The QMU comprises the Quality Management Representative (Sr Mr J.Chong Teck Lee), the Quality Document Control Coordinator (Miss Estellita Crispin) and a pool of qualified internal quality auditors from the various divisions and branches. Last, but not least, we would also like to thank our ISO Advisor (Dr Loo Koi Sang) for his contribution and support.

Sunday, 9 August 2009

Satellite Imagery & Elevation Data for Malaysian Road Engineers

Our road engineers have always been an early adopter of new mapping products in the route selection and preliminary design stage of their highway construction process. On August 8, 2009, I was honoured in being invited by the Road Engineering Association Malaysia (REAM) to deliver a talk during their "Library Talk" session.

A 60-minute presentation on the above caption and interaction with the engineers was definitely a satisfying experience, even though it is somewhat uncommon thing for me to do on a Saturday morning. The entire proceeding was video-taped and I was told it will be uploaded to YouTube soon. I will link it to this blog for your viewing pleasure as and when it becomes available.

A summary of the talk is as follows:

From the line maps produced by analogue photogrammetric means in the early '80s to the fully digital line maps produced by analytical plotters in the late '80s, road engineers have followed closely the technology highway to ensure that the highways they planned and designed in Malaysia are done in an efficient manner.

Digital aerial orthophoto maps of the '90s were the first examples of digital images known to the road engineering fraternity. In 2000, the 1m high-resolution satellite IKONOS image became available. Over the years, it establishes itself as the "mainstream" data for route selection and preliminary design of proposed highways in Malaysia. There is no looking back after that.

With the introduction of new Geoeye1 0.5m resolution and RMSE 3m satellite images, road engineers can now reap the benefits of detail and accuracy that space technology has to offer. For the moment, the leap in accuracy from 25m (of IKONOS) to 3m (of Geoeye1) has definitely quench the current thirst for accurate planning data.

In contrast with the progress made in image resolution and geometric accuracy of satellite-based images, little has changed in the availability of uniform and complete elevation data in Malaysia. The only "nationwide" elevation data available in this country was the contour lines derived from 1:50,000 scaled topo sheets produced by the national mapping agency since the '80s. The NEXTMap Malaysia IFSAR elevation data set is now ready to be "the data of choice" over the next few years.

The combination of Geoeye1 satellite image and IFSAR elevation data (mixing better detail with accuracy) now caters for most preliminary planning and design requirements of road projects. Who knows what technology can bring over the coming years. 3D terrain visualization is the logical next step in the merging of the two different sets of data for us (imagine having the whole project site in 3D in front of you, giving a better understanding and presentation of the ground condition in the comfort of an office environment is something you road engineers had wanted all this while, right?). Road design and development is getting more easy and affordable, all thanks to the much improved availability of image and elevation data.

Written by: Kong Hin Yew

Wednesday, 5 August 2009

Pansharpening of Orthorectified Radar Image

The launching of the NEXTMap Malaysia products has generated a lot of interest in the country. This is understandable. Having a nationwide coverage of high-resolution elevation data has put Malaysia into the forefront as only a handful of countries in the world have such a "privilege". The potential of this set of elevation data is undeniably high. However, many overlook the usefulness of the accompanied image file called the Orthorectified Radar Image (ORI).

ORI at 1.25m over Tawau, Sabah.

ORI, as the name implies, is an accurate image which is orthorectified! Having an accuracy of RMSE 2m, it can be used in many applications. 2D and 3D feature extraction is one application that may interest many. Another area of interest will be in the use of ORI as a reference data to geometrically correct other images of lesser accuracy, thus avoiding the need to collect Ground Control Points (GCP) in the field.

Zoom-in of 1.25m ORI

Unfortunately, as with all other radar images, ORI shares the same disadvantage in being difficult to be interpreted. This has somehow discourages users from utilizing it to its full potential. In order to enhance its usefulness, we can actually "colourize" the ORI. By applying a technique called Pan-sharpening, a black and white ORI can be processed to "become" a color image.

Pan-sharpening is an image processing technique where a high-resolution panchromatic (Black and White image, in this case, the ORI) is "combined" with a low-resolution multispectral image (for example, SPOT 10m XS), to produce a multispectral high-resolution image. Some other common terms used for this process are resolution merge and image fusion.

SPOT 10m XS over Tawau, Sabah

SPOT 10m MS , zoom in

To further study the result of such image processing technique, a test case was conducted using a 1.25m resolution sample ORI over Tawau as the high-resolution panchromatic image. Several options were debated e.g. the low-resolution multispectral images. The final decision was made based on the principle that the multispectral image must be of reasonably low-cost, so that it will not introduce to much additional costs thus making the whole operation commercially not viable. SPOT 10m XS image was eventually used.

Commercial software ERDAS Imagine 9.1 was used, and the resolution merge with the multiplicative option was utilized. The result was quite impressive. Since this research was carried out mainly to make the ORI more visually appealing, not much effort was put to maintain the accuracy of the spectral value.

Pan-sharpened ORI, 1.25m

Pan-sharpened ORI, 1.25m - zoom in

With the Pan-sharpened ORI showing more promising potential in distinguishing features such as empty land versus grassland, roads versus traffic islands and median of roads, it has definitely improve the interpretation. Such a product not only provides an option to extract features, but also as a complementary product to be used in patching up cloudy areas of optical data given its cloud-free nature. This particular property of IFSAR ORI will definitely serve the market appropriately as cloud coverage is a constant "hindrance" to optical system operators working in this region.

Cloudy Scene - Quickbird Image 0.6m

Quickbird Image Patched with Pan-sharpened ORI - Cloud-free Image

Researched and written by: Kong Hin Yew

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