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

2007.04.06 18:41 "Re: [Tiff] Floating point RGBA", by Chris Cox

LZW will expand floating point data, as it frequently does with 16 bit data.

ZIP does a decent job with straight floating point values.

But to get good compression, you need a predictor that knows about the floating point format. (and I'm still researching better ones)


On 4/5/07 1:04 PM, "Toby Thain" <toby@smartgames.ca> wrote:

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.


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