High dynamic range subjective testing
1
Citation
0
Reference
10
Related Paper
Citation Trend
Abstract:
This paper describes of a set of subjective tests that the authors have carried out to assess the end user perception of video encoded with high dynamic range technology when viewed in a typical home environment. Viewers scored individual single clips of content, presented in High Definition (HD) and Ultra High Definition (UHD), in Standard Dynamic Range (SDR), and in High Dynamic Range (HDR) using both the Perceptual Quantiser (PQ) and Hybrid Log Gamma (HLG) transfer characteristics, and presented in SDR as the backwards compatible rendering of the HLG representation. The quality of HD SDR was improved by approximately equal amounts by either increasing the dynamic range or increasing the resolution to UHD. A further smaller increase in quality was observed in the Mean Opinion Scores of the viewers by increasing both the dynamic range and the resolution, but this was not quite statistically significant.Keywords:
Dynamic range compression
High-dynamic-range imaging
Mean opinion score
High Dynamic Range (HDR) imaging technologies can provide high levels of immersion through a dynamic range that meets and even exceeds the instantaneous range of the Human Visual System (HVS). This increase in the level of immersion comes at the cost of significantly higher bit-rate requirements compared to those associated with conventional imaging technologies. As a result, efficient HDR-relevant coding solutions have to be developed. In this paper, we present a review of existing HDR image and video coding methods, thus establishing the current state of the art. We additionally present some of our own recent results in this area.
High-dynamic-range imaging
Dynamic range compression
Immersion
Cite
Citations (20)
An encoding method of the high dynamic range (HDR) images based on Vector Quantization is discussed. The HDR images have much higher dynamic ranges compared with the low dynamic range (LDR) images. Due to its high dynamic range, the size is often huge, thus development for functional compression is needed. On the other hand, we often need to convert them into the LDR images because the existing output devices cannot directly output the dynamic ranges of HDR images. Our goal is to develop a HDRI compression method that minimizes the error of the tone-mapped LDR images. Therefore we applied the adjustment of scale and the evaluation of the error in the log domain. Our method improves a compression performance, compared to methods that directly apply the conventional vector quantization to the HDR images.
Tone mapping
Dynamic range compression
High-dynamic-range imaging
Cite
Citations (0)
HDR (High Dynamic Range) imaging is an area of increasing importance but most display devices still has LDR (Limited Dynamic Range). While retaining important visual information, various techniques have been proposed for compressing the dynamic range. When used for range compression, multi-scale image processing techniques widely used for many image processing tasks have a reputation of causing halo artifacts. However, they can work when properly implemented as demonstrated. A symmetrical analysis-synthesis filter bank is used and a local gain control is applied to the sub-bands. As also shown, the technique can be adapted for the related problem of inverse tone mapping in which a HDR image is converted to a LDR image and later expanded back to HDR image.
Tone mapping
High-dynamic-range imaging
Dynamic range compression
Inverse filter
Cite
Citations (0)
High dynamic range (HDR) imaging is an area of increasing importance, but most display devices still have limited dynamic range (LDR). Various techniques have been proposed for compressing the dynamic range while retaining important visual information. Multi-scale image processing techniques, which are widely used for many image processing tasks, have a reputation of causing halo artifacts when used for range compression. However, we demonstrate that they can work when properly implemented. We use a symmetrical analysis-synthesis filter bank, and apply local gain control to the subbands. We also show that the technique can be adapted for the related problem of "companding", in which an HDR image is converted to an LDR image, and later expanded back to high dynamic range.
Companding
Dynamic range compression
High-dynamic-range imaging
Filter bank
Wide dynamic range
Cite
Citations (44)
HDR (High Dynamic Range) imaging is an area of increasing importance but most display devices still has LDR (Limited Dynamic Range). While retaining important visual information, various techniques have been proposed for compressing the dynamic range. When used for range compression, multi-scale image processing techniques widely used for many image processing tasks have a reputation of causing halo artifacts. However, they can work when properly implemented as demonstrated. A symmetrical analysis-synthesis filter bank is used and a local gain control is applied to the sub-bands. As also shown, the technique can be adapted for the related problem of inverse tone mapping in which a HDR image is converted to a LDR image and later expanded back to HDR image.
Tone mapping
High-dynamic-range imaging
Dynamic range compression
Inverse filter
Cite
Citations (0)
High dynamic range images enable more detailed information regarding the content. By performing luminance compression, images can be prepared for the traditional low dynamic range reproduction. There are numerous ways to perform the compression (tone-mapping), but the content may affect the image quality. The reduction of dynamic range may produce unwanted effects (e.g. due to noise) and can be tailored for specific image content. In this paper we analyze several examples related to synthetic aperture radar (SAR) as images with high dynamic range.
Tone mapping
Dynamic range compression
High-dynamic-range imaging
Cite
Citations (4)
Tone manipulation is a luminance compression, which usually causes darker tones to appear brighter and distorts contrast relationships. Tone mapping reduces the dynamic range or contrast ratio of the entire image. High Dynamic range imaging is an attractive technique to capture real world luminance in the scene for each pixel. Various tone mapping operators such as Drago, Reinhard, Ward, Ashikmin, Piecewise, Retinex are available for converting high dynamic range images to displayable low dynamic range image. The performance of various tone mapping operators are evaluated. Multiple exposure pictures are combined together to form a High Dynamic Range image (HDR) and tone mapping operators are applied to form Low Dynamic Range image (LDR) and the result images are compared with the original image. Color correction and Hierarchical tone mappings are applied to enhance the image quality.
Tone mapping
High-dynamic-range imaging
Tone (literature)
Dynamic range compression
Wide dynamic range
Cite
Citations (4)
This paper describes of a set of subjective tests that the authors have carried out to assess the end user perception of video encoded with High Dynamic Range technology when viewed in a typical home environment. Viewers scored individual single clips of content, presented in High Definition (HD) and Ultra High Definition (UHD), in Standard Dynamic Range (SDR), and in High Dynamic Range (HDR) using both the Perceptual Quantizer (PQ) and Hybrid Log Gamma (HLG) transfer characteristics, and presented in SDR as the backwards compatible rendering of the HLG representation. The quality of SDR HD was improved by approximately equal amounts by either increasing the dynamic range or increasing the resolution to UHD. A further smaller increase in quality was observed in the Mean Opinion Scores of the viewers by increasing both the dynamic range and the resolution, but this was not quite statistically significant.
Dynamic range compression
High-dynamic-range imaging
Wide dynamic range
Cite
Citations (4)
High dynamic range (HDR) imaging is an area of increasing importance, but most display devices still have limited dynamic range (LDR). Various techniques have been proposed for compressing the dynamic range while retaining important visual information. Multi-scale image processing techniques, which are widely used for many image processing tasks, have a reputation of causing halo artifacts when used for range compression. However, we demonstrate that they can work when properly implemented. We use a symmetrical analysis-synthesis filter bank, and apply local gain control to the subbands. We also show that the technique can be adapted for the related problem of "companding", in which an HDR image is converted to an LDR image, and later expanded back to high dynamic range.
Companding
Dynamic range compression
High-dynamic-range imaging
Filter bank
Tone mapping
Wide dynamic range
Cite
Citations (248)
Technique of high dynamic range imaging (HDRI) was introduced into conventional high dynamic range display (HDRD). Sharpness of image was further enhanced by improving local contrast ratio in the HDRI-based high dynamic range display
High-dynamic-range imaging
Wide dynamic range
Tone mapping
Dynamic contrast
Cite
Citations (4)