| .TH VIPSTHUMBNAIL 1 "13 May 2010" |
| .SH NAME |
| vipsthumbnail \- make thumbnails of image files |
| .SH SYNOPSIS |
| .B vipsthumbnail [flags] imagefile1 imagefile2 ... |
| .SH DESCRIPTION |
| .B vipsthumbnail(1) |
| processes each |
| .B imagefile |
| in turn, shrinking each image to fit within a 128 by 128 pixel square. |
| The shrunk image is written to a new file named |
| .B tn_imagefile.jpg. |
| This program is typically quite a bit faster and uses much less memory than |
| other image thumbnail programs. |
| |
| For example: |
| |
| $ vipsthumbnail fred.png jim.tif |
| |
| will read image files |
| .B fred.png |
| and |
| .B jim.tif |
| and write thumbnails to the files |
| .B tn_fred.jpg |
| and |
| .B tn_jim.jpg. |
| |
| $ vipsthumbnail --size=64 -o thumbnails/%s.png fred.jpg |
| |
| will read image file |
| .B fred.jpg |
| and write a 64 x 64 pixel thumbnail to the file |
| .B thumbnails/fred.png. |
| |
| .SH OPTIONS |
| .TP |
| .B -s N, --size=N |
| Set the output thumbnail size to |
| .B N |
| x |
| .B N |
| pixels. The image is shrunk so that it just fits within this area, Images |
| which are smaller than this are expanded. |
| |
| .TP |
| .B -o FORMAT, --output=FORMAT |
| Set the output format string. The input filename has any file type suffix |
| removed, then that value is substitued into |
| .B FORMAT |
| replacing |
| .B %s. |
| The default value is |
| .B tn_%s.jpg |
| meaning JPEG output, with |
| .B tn_ |
| prepended. You can add format options too, for example |
| .B tn_%s.jpg:20 |
| will write JPEG images with Q set to 20. |
| |
| .TP |
| .B -d N, --disc=N |
| Set disc use threshold to |
| .B N. |
| Images which cannot be opened directly need to be decompressed first. Images |
| which are smaller than |
| .B N |
| are decompressed to memory, images which are larger are decompressed to |
| temporary files. Use the |
| .B TMPDIR |
| environment variable to change the location for temporary files. |
| |
| .TP |
| .B -p I, --interpolator=I |
| Resample with interpolator |
| .B I. |
| Use |
| .B vips --list classes |
| to see a list of valid interpolators. The default is |
| .B bilinear. |
| |
| .TP |
| .B -n, --nosharpen |
| By default, |
| .B vipsthumbnail(1) |
| will sharpen thumbnails slightly to make them look more pleasing. This option |
| disables this sharpening. |
| |
| .TP |
| .B -e PROFILE, --eprofile=PROFILE |
| Export thumbnails with this ICC profile. Images are only colour-transformed if |
| there is both an output and an input profile available. The input profile can |
| either be embedded in the input image or supplied with the |
| .B --iprofile |
| option. |
| |
| .TP |
| .B -i PROFILE, --iprofile=PROFILE |
| Import images with this ICC profile, if no profile is embdedded in the image. |
| Images are only colour-transformed if |
| there is both an output and an input profile available. The output profile |
| should be supplied with the |
| .B --oprofile |
| option. |
| |
| .TP |
| .B -l, --nodelete |
| Don't delete the profile from the output image. Since all output images will |
| generally have the same profile, |
| .B vipsthumbnail(1) |
| will usually delete it. This option leaves the profile inside the image. |
| |
| .TP |
| .B -v, --verbose |
| .B vipsthumbnail(1) |
| normally runs silently, except for warning and error messages. This option |
| makes it print a list of the operations it performs on each image. |
| |
| .SH RETURN VALUE |
| returns 0 on success and non-zero on error. |
| .SH SEE ALSO |
| header(1) |