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33:-photonmapper at a time where storage space was a crucial factor. Its implementation in TIFF also allowed the combination with image-compression algorithms without great programming effort. As such it has to be considered a smart compromise between the imposed limitations. It is slightly related to
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artifacts clearly visible to human observers. Using a triplet of floats to represent RGB would be a viable solution, but it would quadruple the size of the file (occupying 32 bits for each color-component, as opposed to 8 bits).
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Logluv TIFF's design solves two specific problems: storing high-dynamic image data and doing so within a reasonable amount of space. Traditional image format generally stores pixel data in
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Reading and writing of Logluv TIFF images can be handled via LibTIFF. LibTIFF is freely available in both source and various binary packages for different platforms.
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occupying 24 bits, with 8 bits for each color component. This limits the representable colors to a subset of all visible and distinguishable colors, introducing
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with imperceptible step sizes. In order to provide the required high dynamic range with imperceptible luminance steps, LogLuv uses 16 bits to encode a
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range of nearly 128 stops. The space occupied by one pixel is thus 32 bits (L16 + U8 + V8), marginally bigger than a standard 8 bit RGB-image.
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In an attempt to prevent the expansion of data-size, Logluv comes in a 24-bit flavour, which in a rather complicated way quantizes
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211:(Amazon Link) High Dynamic Range Imaging by Erik Reinhard, Greg Ward, Sumanta Pattanaik, Paul Debevec
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data inside a TIFF image. It was originally developed by Greg Ward for storing HDR-output of his
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For those looking for Logluv images, there are numerous example on Greg Ward Larson's page.
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Ward Larson, Gregory (1998). "LogLuv
Encoding for Full-Gamut, High-Dynamic Range Images".
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HDRI, by
Reinhard et al. has a discussion regarding Logluv Tiff in the 3rd chapter.
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to 10 bit and merges U/V into a 14-bit look-up based value.
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LogLuv encoding for full-gamut, high-dynamic range images
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Instead of using RGB, LogLuv uses the logarithm of the
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color space. LogLuv allocates 8 bits for each of the
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A comparison of different HDR image encoding formats
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Greg Ward Larson on LogLuv
Encoding for TIFF Images
101:base 2 logarithm of the luminance, which allows an
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847:Exchangeable image file format (Exif)
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857:Extensible Metadata Platform (XMP)
125:Logluv TIFF has widespread use in
81:coordinates in order to provide a
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235:Appears to be the same paper as:
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25:is an encoding used for storing
925:High dynamic range file formats
251:10.1080/10867651.1998.10487485
1:
920:Raster graphics file formats
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129:applications such as IBL,
27:high-dynamic-range imaging
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239:Journal of Graphics Tools
930:Photographic techniques
546:PBM / PGM / PPM / PNM
303:Graphics file formats
159:Tag Image File Format
131:image-based lighting
83:perceptually uniform
862:GIF § Metadata
198:2004-09-16 at the
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164:RGBE image format
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193:LibTIFF Homepage
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867:Steganography
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245:(1): 15–31.
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79:chromaticity
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51:quantization
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19:
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601:Logluv TIFF
99:fixed-point
16:File format
914:Categories
898:Comparison
180:References
635:UFO / UFP
571:PSD / PSB
484:JPEG 2000
444:ICO / CUR
140:Resources
115:lightness
109:Extension
63:luminance
47:RGB-space
886:Category
839:Metadata
781:Compound
509:JPEG-HDR
196:Archived
169:JPEG-HDR
153:See also
65:and the
55:clamping
31:Radiance
628:TIFF/IT
623:TIFF/EP
504:JPEG XT
499:JPEG XS
494:JPEG XR
489:JPEG XL
479:JPEG-LS
41:Details
20:Logluv
736:Gerber
698:Vector
561:PICtor
311:Raster
174:CIELUV
89:’ and
67:CIELUV
804:MODCA
464:JBIG2
354:BSAVE
121:Usage
95:gamut
829:XAML
814:PICT
794:DjVu
751:PGML
746:IGES
741:HVIF
731:EMF+
683:CIFF
645:WebP
640:WBMP
618:TIFF
596:RGBE
586:QTVR
531:NRRD
526:MIFF
474:JPEG
459:JBIG
454:ILBM
439:ICNS
434:ICER
429:HEVC
424:HDRi
409:FLIF
404:FLIC
399:FITS
339:AVIF
329:APNG
324:ANIM
127:HDRI
53:and
35:RGBE
22:TIFF
824:SWF
809:PDF
799:EPS
789:CDF
771:Xar
766:WMF
761:VML
756:SVG
726:EMF
721:DXF
716:CGM
711:CDR
688:DNG
675:Raw
665:XWD
660:XPM
655:XCF
650:XBM
613:TGA
608:SGI
591:RAS
581:QOI
576:PSP
566:PNG
556:PGF
551:PCX
541:PAM
536:ORA
521:MNG
516:KRA
469:JNG
449:ICS
419:GIF
414:FPX
394:EXR
389:ECW
384:DPX
379:DDS
374:CPT
369:CPC
364:CIN
359:CAL
349:BPG
344:BMP
334:ART
319:ANI
247:doi
77:’)
73:’,
916::
819:PS
706:AI
241:.
133:.
103:EV
295:e
288:t
281:v
253:.
249::
243:3
91:v
87:u
75:v
71:u
69:(
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