2007.04.05 16:07 "[Tiff] Floating point RGBA", by mark meijer

2007.04.05 20:04 "Re: [Tiff] Floating point RGBA", by Toby Thain

On 5-Apr-07, at 4:58 PM, Craig Bruce wrote:

That seems like a very strange combination. If I remember correctly, packbits is a byte-based RLE scheme. Applied to floating point data, compression ought to be very inefficient.

It may be a sensible option if the image has significant regions of solid black. The IEEE floating-point representation of 0.0 is: 0x00, 0x00, 0x00, 0x00 (in either endian).

Dictionary compressors are much more likely to win, overall. RLE does seem an odd choice, regardless of the actual data characteristics.

--Toby

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