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)
Chris
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.
--Toby
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