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2008.03.29 16:26 "Re: TIFFReadRawStrip buffer data type", by James Sumners
This is the specifications on the image as my program sees it: Input image specifications: 512x512 photo = 1 8bpp 1spp order = 0 res_unit = 2 xres = 72.000000 yres = 72.000000 compression: 1 rows per strip: 64 strips: 8 bytes per strip: 32768 And as the tiffinfo utility sees it: TIFF Directory at offset 0x40008 (262152) Subfile Type: (0 = 0x0) Image Width: 512 Image Length: 512 Resolution: 72, 72 pixels/inch Bits/Sample: 8 Compression Scheme: None Photometric Interpretation: min-is-black Orientation: row 0 top, col 0 lhs Samples/Pixel: 1 Rows/Strip: 64 Planar Configuration: single image plane So it looks like I am working with the data under the optimal conditions you specify. On Sat, Mar 29, 2008 at 11:41 AM, Bob Friesenhahn <bfriesen@simple.dallas.tx.us> wrote: > On Sat, 29 Mar 2008, James Sumners wrote: > > > > Well, the image I'm reading is not compressed. So I thought the data > > would just be the integer color value of each pixel. If that is > > incorrect, how would I get that data? I want to be able to work with > > the color values for the pixels so that I can do my own compression. > > If the image is not compressed, then you should be ok. What is the > bits-per-sample of your data? If it is 8 and you are using the RGB > photometric with three samples per pixel, then each byte would be one > sample representing R, G, or B. If bits-per-sample is 1, 2, or 4 then > there is much more work to do since multiple samples will be packed in > a byte. > > > > Bob > ====================================== > Bob Friesenhahn > bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/ > GraphicsMagick Maintainer, http://www.GraphicsMagick.org/ > > -- James Sumners http://james.roomfullofmirrors.com/ "All governments suffer a recurring problem: Power attracts pathological personalities. It is not that power corrupts but that it is magnetic to the corruptible. Such people have a tendency to become drunk on violence, a condition to which they are quickly addicted." Missionaria Protectiva, Text QIV (decto) CH:D 59