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glViewImage (version 1.5.0)

Screenshot from "glViewImage"
Screenshot from "glViewImage"

glViewImage is an image viewer, converter and even a very limited image editor.

  1. Download
  2. Features
  3. Running
  4. Special keys
  5. Command-line options
  6. Image saving notes
  7. Requirements

1. Download

Download glViewImage:
 Linux<br/>(32 bit)
(32 bit)
 Linux<br/>(64 bit, x86_64)
(64 bit, x86_64)
 Windows<br/>(32 bit, works on 64-bit too)
(32 bit, works on 64-bit too)
 Mac OS X<br/>(32 bit)
Mac OS X
(32 bit)

If you like this software, please consider donating.

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.

2. Features

glViewImage was originally developed to test and demonstrate the power of image handling inside our Castle Game Engine , but it became quite usable utility on it's own. Viewed image can be quickly scaled and moved, you can browse images list, you can test how image looks when tiled (to test is it good for a texture or desktop wallpaper), you can see how alpha channel of the image looks on various background colors. The ability to load and save even some uncommon image formats (DDS, RGBE) is also very useful.

Many image formats are supported:

3. Running

You can simply run the glViewImage without parameters, and open / save images using the menu commands.

4. Special keys

Keys not available as menu items:
Arrows move image
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 jpg or jpeg, RGBE images - rgbe or pic, rest is obvious.

Opened image is also added to the image list.

5. Command-line options

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:

Running glViewImage with no parameters is equivalent to running
  glViewImage .
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.

6. Image saving notes

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 DDS files) will be always decompressed, and saving them back will always make uncompressed files.

7. Requirements

convert program from ImageMagick package must be available on $PATH for some image formats to work.