I'm scanning some old family photos using Image Capture. I want a lossless image using TIFF and LZW compression. What I'm seeing, thanks to the tiffutil -info <file>
command, is that the .tiff files that are being outputted are getting a mix of Compression Scheme: Lempel-Ziv & Welch encoding
(aka LZW) and Compression Scheme: JPEG encoding
.
- Does anyone know why Image Capture would switch compression formats? I can't seem to find a pattern as to when it does this but it does seem dependent on the image being scanned.
- Is there a way to force it to use LZW, always?
- Why would anyone want a lossy compression (JPEG) inside a format (TIFF) generally known for being lossless?
Here are some examples of scanned images. The full TIFFs are available in this Dropbox folder.
Here is the corresponding tiffutil
output:
1.tiff: JPEG compression support is not configured.
Directory at 0x8
Image Width: 1515 Image Length: 2639
Resolution: 600, 600
Resolution Unit: pixels/inch
Bits/Sample: 8
Sample Format: unsigned integer
Compression Scheme: JPEG encoding
Photometric Interpretation: RGB color
Alpha: Present
FillOrder: msb-to-lsb
Predictor: none
Software: "Apple Image Capture"
Model: "Brother HL-L3290CDW series"
Orientation: row 0 top, col 0 lhs
Samples/Pixel: 4
Rows/Strip: 16
Number of Strips: 165
Planar Configuration: Not planar
Profile Name: Scanner RGB Profile
*** 2.tiff
Directory at 0x8
Image Width: 1520 Image Length: 2641
Resolution: 600, 600
Resolution Unit: pixels/inch
Bits/Sample: 8
Sample Format: unsigned integer
Compression Scheme: Lempel-Ziv & Welch encoding
Photometric Interpretation: RGB color
Alpha: Present
FillOrder: msb-to-lsb
Predictor: horizontal differencing
Host Computer: "Apple Mac OS X"
Software: "Apple Image Capture"
Make: "Brother"
Model: "HL-L3290CDW series"
Orientation: row 0 top, col 0 lhs
Samples/Pixel: 4
Rows/Strip: 21
Number of Strips: 126
Planar Configuration: Not planar
Profile Name: Generic RGB Profile