glViewImage is an image viewer, converter and even
a very limited image editor.
No installation is required. Just download and unpack these archives wherever
you want, and run the program inside. The documentation
(this web page) is also included inside
(look in the
documentation/ subdirectory) for offline viewing.
This is free/open-source software. Developers can download sources of this program.
glViewImage was originally developed to demonstrate
the power of image handling inside our Castle Game Engine. It became quite useful utility on it's own, with the following features:
Pfor next, previous).
Many image formats are supported:
glViewImageyou can view all subimages within one DDS file, see menu items Images->Next/Previous subimage in DDS. Saving to DDS images is also supported. Details about using DDS format for textures in our engine are here.
TIFF, SGI, JP2, EXR:
To load and save these images, you need to install
package, and make sure it's
convert program is available on $PATH.
Then our engine will recognize these image formats,
and seamlessly load/save them (by running
convert "under the hood").
You can simply run the
glViewImage without parameters,
and open / save images using the menu commands.
|Keys not available as menu items:|
|Arrows + Ctrl||move image 10 x faster|
|- / +||scale image (smaller / larger)|
|x / X||scale only horizontally (smaller / larger)|
|y / Y||scale only vertically (smaller / larger)|
Notes about opening image:
glViewImage guesses image format using file extension (yes, yes,
I will change it at some time to recognize image format based on
file content), so it's important for files to have good
filename extension. JPEG images may have extension
jpeg, RGBE images -
rest is obvious.
Opened image is also added to the image list.
glViewImage remembers image list that you can browse using N (next image on the list) and P (previous image on the list) keys. When you run glViewImage you can give it as parameters a list of images to browse.
Every parameter must be one of:
A directory name — glViewImage will display all images found in this directory.
glViewImage ~/my_images/ to display
all images in
A filename — glViewImage will display this image, and also allow to browse (by previous/next) other images in the same directory.
@<filename> — glViewImage will read
image filenames from file
each line is one filename
<filename> "-" means "standard input", as usual;
so you can pipe output of e.g.
find program to glViewImage).
glViewImage with no parameters is equivalent
so you will view all images (that glViewImage can handle) in the current directory. If none found, the default welcome image will be displayed.
Oh, and (as usual) all parameters described in those pages:
standard options understood by my OpenGL programs and some notes about command-line options understood by my programs are available. If you will not give any parameter that forces some
window size (like
--geometry) then program will open a window
with the same size as the first displayed image.
Resulting image format is determined by filename extension, unknown extension will result in error.
Image loaded and displayed by glViewImage is internally always stored in format comfortable for OpenGL. This includes many formats, but not RGBE. It means that if you will load RGBE image to glViewImage and then you will save it (even to the RGBE format again) then you loose RGBE precision (and clamp color values above 1.0).
Also, S3TC compressed images (from KTX, DDS files) will be always decompressed, and saving them back will always make uncompressed files.
convert program from
package must be available on $PATH for some image formats to work.