|
|
|
|
|
|
Proposed deep chain HDRI architecture. Given an LDR image with a middle exposure value (EV 0), the EV ±1, ±2, ±3 images are inferred sequentially through the network. When the EV of the inferred image is far from the middle exposure value, the structure depth goes deeper than that of the image that has less exposure difference to infer the mapping relation more accurately. After finishing the process through the proposed network, a total of six LDR images are inferred to generate the LDR image stack. Using an HDRI synthesis technique (e.g. the method of Debevec and Malik, etc.), an HDR image is generated from the pseudo multi exposure stack. |
Recently, high dynamic range (HDR) imaging has attracted much attention as a technology to reflect human visual characteristics owing to the development of the display and camera technology. This paper proposes a novel deep neural network model that reconstructs an HDR image from a single low dynamic range (LDR) image. The proposed model is based on a convolutional neural network composed of dilated convolutional layers and infers LDR images with various exposures and illumination from a single LDR image of the same scene. Then, the final HDR image can be formed by merging these inference results. It is relatively simple for the proposed method to find the mapping between the LDR and an HDR with a different bit depth because of the chaining structure inferring the relationship between the LDR images with brighter (or darker) exposures from a given LDR image. The method not only extends the range but also has the advantage of restoring the light information of the actual physical world. The proposed method is an end-to-end reconstruction process, and it has the advantage of being able to easily combine a network to extend an additional range. In the experimental results, the proposed method shows quantitative and qualitative improvement in performance, compared with the conventional algorithms. |
| |
|
S. Lee, G.H. An, S-J. Kang. Deep Chain HDRI: Reconstructing a High Dynamic Range Image from a Single Low Dynamic Range Image IEEE Access, 2018. (hosted on IEEE Access) |
Future works
Tone mapping:
|
Selected references to our work
|
Acknowledgements
|