GNOME Bugzilla – Bug 782933
G3/G4 fax compression options do not working on export images, scanned by Xsane-GIMP-plugin, to tiff/tif
Last modified: 2018-05-24 17:51:55 UTC
Hi. I detect that when I use Xsane-GIMP-plugin to scan paper using black/white (monochrome = 1 bit) mode & tiff, then after try to export scanned image as tiff or tif, G3/G4 fax compression options will be NOT available (being inactive & can not checked) !! While when I use original Xsane application, no such thing ! The result of this bug is that files sizes by Xsane-GIMP-plugin will be larger than that by original Xsane application ! I'm not sure whether thin is due to defect in Xsane-GIMP-plugin or in GIMP itself. Please fix this kindly. Best.
Could be the image mode or existence of an alpha channel. Both would be set by the plug-in.
Or a palette with >2 colors? Please attach a (small) image freshly scanned without any modifications which you expect to export like that as TIFF. Simply save it as XCF so we can see all its properties.
Hi. I attached 3 samples: 1) test.xcf : as you asked 2) test-noncompression.tif : export as .tif but without compression. Please notice that "without compression" is according to window that appearing after clicking "export", but in "setup" of Xsane-GIMP-plugin in "filetype" there is by default compression to lineart as G3 fax !! 3) test-deflate.tif : export as .tif with selection of "deflate" compression type. -------------- Please notice that: 1) I select from GUI of Xsane-GIMP-plugin "Lineart" as a mode for scanning & resolution at 300 dpi. 2) this problem not existing by original Xsane application: it seem that GIMP window of compression options that appearing to user after click on "export as" undo G3 fax default compression of plugin ......
Created attachment 352457 [details] test.xcf
Created attachment 352458 [details] test-noncompression.tif
Created attachment 352459 [details] test-deflate.tif
Thanks. Will check those.
Both images load as greyscale. If the mode is changed to Indexed, then G3 and G4 become available on export, as expected.
@Michael Schumacher Why? Why images loaded as grayscale though I used "Lineart" scanning mode to scan them ? They should loaded as "Indexed" by default not as grayscale as long as used scan mode is "Lineart", are not they ? The image should loaded as grayscale by default only if mode used to scan them is "grayscale", are not they ? This should be fixed ! I'm sure that many users will not discover this by themselves .... But, dear do you (or other GIMP team members) have hand to managed & develop Xsan-GIMP-plugin or not ? Original developer of it seem to stop from developing it. Though his site still existing but he did not replay on my e-mails.
The TIFF plug-in can create indexed images - the "Type: grayscale" in the metadata (see below) might cause it to opt for grayscale instead, though. I guess the indexed state could be determined from the "Depth: 1 bits-per-pixel component", but I'll leave this for people more familiar with TIFF. > identify -verbose test-nocompression.tif Image: test-nocompression.tif Format: TIFF (Tagged Image File Format) Geometry: 1417x1766 Class: DirectClass Type: grayscale Depth: 1 bits-per-pixel component Channel Depths: Gray: 1 bits Channel Statistics: Gray: Minimum: 0.00 (0.0000) Maximum: 255.00 (1.0000) Mean: 243.39 (0.9545) Standard Deviation: 53.16 (0.2085) Resolution: 300x300 pixels/inch Filesize: 2.4M Interlace: No Orientation: TopLeft Background Color: white Border Color: #DFDFDF Matte Color: #BDBDBD Page geometry: 1417x1766+0+0 Compose: Over Dispose: Undefined Iterations: 0 Compression: No Document: /home/user1945/Desktop/test.tif Signature: d29c790ee6d09bb0f9b3a8702e964d1d873ca5258c402be28540735d45399104 Tainted: False User Time: 0.031u Elapsed Time: 0:01 Pixels Per Second: 18.9M
-- GitLab Migration Automatic Message -- This bug has been migrated to GNOME's GitLab instance and has been closed from further activity. You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.gnome.org/GNOME/gimp/issues/1101.