11 | | Additionally to the need for a basic data-set, the demand for further spatial input parameters, which will be developed in this work package, has been identified during the development of PALM in MOSAIK-1. Therefore, the goal of work package WP-S5.2 is to improve the surface input parameters for PALM-4U in two different ways: |
| 10 | '''I) Development of analysis-ready surface data sets''' |
| 11 | || |
| 12 | The work in MOSAIK Phase 1 showed the importance of an automated generation of surface input parameters, as well as the provisioning of analysis-ready data. As not all municipalities have the same data available at the same level of detail, it was deemed important to provide base-layers that consistently provide a minimum amount of spatial input parameters, which can be supplemented, if necessary, with local parameters. This basic data-set should only consist of freely accessible data, if possible, to allow their use for everyone intending to test PALM-4U. Many open-source data not only exist for Germany, but also for Europe and globally. Therefore, such base-layers allow the transferability of PALM-4U to cities outside of Germany. |
| 13 | In addition to deriving and providing the data layers themselves, work is performed to create and document stand-alone data retrieval software, which could then be distributed with PALM-4U allowing input data retrieval and preparation also on the user side. |
| 14 | || |
| 15 | '''II) Development of methods to integrate new high-resolution input data.''' |
| 16 | || |
| 17 | In addition to the need for a consistent base-layer data-set, the demand for further spatial input parameters has been identified during the development of PALM in MOSAIK-1. Therefore, the second goal of this work package is to explore new methods of deriving information not readily available in other published data-sets. In particular, we are looking to improve the description of building characteristics from aerial imagery using novel machine learning approaches. |
32 | | PI: Dr. Wieke Heldens |
33 | | || |
34 | | === Deliverables: |
35 | | || |
36 | | || |
37 | | === Progress so far: |
38 | | || |
| 44 | Recent developments in the realm of artificial intelligence allow for increasingly detailed information retrieval from very high-resolution imagery. In this task we explore the potential of oblique aerial imagery to retrieve detailed building façade information. |
| 45 | To this end, we implemented and trained a deep-learning based classifier, which performs instance segmentation on two-dimensional images. In particular it maps facade window area, an important component of building heat exchange, based on texture images from a 3D city model of Berlin (LOD2 CityGML). Training data, sourced from publicly available data-sets, were used in a first iteration to train a Mask-RCNN model. In a second, transfer-learning step the model was fine-tuned to manually labelled 2d images extracted from the LOD2 data. This final model was the validated and used to annotate all unlabeled textures from the LOD2 data, hence creating a map of façade window fractions. |
| 46 | |
| 47 | {{{ |
| 48 | #!div style="align:center; width: 800px; border: 0px solid" |
| 49 | [[Image(WP-S52-figure2.png,nolink,800px,center)]] |
| 50 | }}} |
| 51 | |
| 52 | |
| 53 | '''Figure 2:''' Model-based extraction of façade window area from oblique aerial imagery (provided in CityGML LOD2 format) by means of an instance segmentation algorithm. |
| 54 | |