NAME¶
gpiv_combing - Combines two single-exposed images into one image file for
cross-correlation.
SYNOPSIS¶
gpiv_combing [
-a |
--suf_a S] [
-b |
--suf_b S] [
-d |
--dt S] [
-h |
--help] [
-p |
--print] [
-s |
--skip
S] [
-t |
--type] [-u |
--suf_num
N] [
-v |
--version] [
-V |
--verbose] [
-w |
--warning]
file_basename
DESCRIPTION¶
gpiv_combing combines two images from a common image format that use
lossless compressing schemes into a Portable Network Graphics image with
extension
.png. The resulting ´double frame´ image is
used for cross-correlation with
gpiv_rr (or
gpiv). Additional
information is added to the image header, like the parameter for enabling
cross correlation, separation time between the recordings of the two images
and the name of this program.
This program uses the
IMG configuration parameters. As the input images
are single-frame and will probably not contain the required X_corr parameter
in its header, the IMG.X_corr setting will have to be set to 0 for the correct
loading.
The default settings may be overruled by the command line options, as explained
below.
Options¶
- -h | --help
- On-line help.
- -a | --suf_a S
- The filename of the first image is generated from the file_basename, the
suffix S (default: _a) and from the image extension type.
- -b | --suf_b S
- The filename of the second image is generated from the file_basename, the
suffix S (default: _b) and from the image extension type.
- -d | --dt S
- The time between subsequent images in milliseconds. The value will be
written to the image header. If -s | --skip is used, the
separation time will be adapted to the correct value.
- -p | --print
- Prints parameters to stdout.
- -s | --skip S
- Skip S numbers; the first image with number N (defined by
-u | --suf_num N) will be combined with the second
image N+S+1 (default: S = 0)
- -t | --type
- Type or format of the input image (default png). Supported formats are:
raw binary (r), hdf5 (gpi), gif, tif, bmp and pgm. The format of the
output image will always be png.
- -u | --suf_num N
- If images are numbered instead of having suffixes _a and _b.
N represents the first of the two numbered frames which will be
combined with frame N + 1. The combined image will be named to
file_basename N.png. So, only odd or even numbered images
will result to be loaded in gpiv_rr (or gpiv) for
cross-correlation.
- -v | --version
- Print version information on standard output, then exit successfully.
- -V | --verbose
- Program behaves verbose during operation, like printing filenames,
separation time.
- -w | --warning
- Checks and warns if one of the two input images already contain an image
pair, i.e. the header parameter X-corr is set TRUE. The program will exit
if this is the case. Besides this warning, the program will always check
if the images are of equal sizes. If an input image does not contain the
X-corr parameter in its header, the parameter will be read from the
parameter resources. Not using this option allows one to keep the settings
in the parameter resources in any state.
- file_basename
- The filename without the image extension (like .png, .tif etc) and suffix
or number.
Examples¶
- Suppose two single-exposed images will have to be combined for
cross-correlation with names image_a.gif and image_b.gif: so the
file_basename will be "image", _a and _b are default suffixes and
the image type has to be defined. The program is used following:
- gpiv_combing -t gif image
- As PNG is default image format, -t key is not needed. Two images with
names turtle_slow.png and turtle_fast.png are combined with:
- gpiv_combing -a _slow -b _fast turtle
- For two numbered images img03.png and img04.png only the starting number
will have to defined:
-
gpiv_combing -u 3 img0
- Two numbered images img03.png and img09.png will have to be combined by
skipping 5 images in-between. If -d | --dt S is used,
the correct separation time between the combined frames is calculated from
S:
- gpiv_combing -u 3 -s 5 img0
SEE ALSO¶
gpivtools
NOTES¶
The program uses
netpbm.
AUTHOR¶
Gerber Van der Graaf