Advanced High Dynamic Range Imaging, 2nd Edition

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HDR Images Compression

The extra information within an HDR image, compared to an LDR image, means that the resultant data files are large. Floating point representations, which were introduced in Chapter 2, can achieve a reduction down to 32/24 bpp (RGBE and LogLuv) from 96 bpp of an uncompressed HDR pixel. However, this memory reduction is not enough and not practical for easily distributing HDR content or storing large databases of images or video. For example, a minute of a high definition movie (1920 × 1080) at 24 fps encoded using the 24 bpp LogLuv format requires more than 8.3 GBytes of space, which is nearly double the space of a single layer DVD. Researchers have been working on more sophisticated compression schemes in the last few ...