Since I'm not maintaining this software anymore... source code is now provided.Source (GPL):
hereA few things were started but never completed... including rebuilding. See spark.txt for the milestones I had.

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I know there are a couple of IMG editors out there... so why another one?
Well, a couple of reasons...
1. New files get added to the end of the IMG file, which means the archive will get bigger and bigger in size... until you rebuild it. But what happens to the space that was reclaimed from deleted files?
2. The concept of keeping the layout state of the archive in memory. What this pretty much means is that you should be able to add new files or delete files from an IMG file without worrying about (a) accidental overwrites of existing files, (b) accidental deletion of existing files. Unless you ask to save, nothing is saved.
3. Integration with other Windows programs... Drag and drop from Explorer (or even winzip/winrar) into a IMG file?
I have been writing a simple IMG editor (named Spark) that takes these factors into account. It's only for GTA:SA for now... it doesn't support the old archive format. As I haven't tested it as much as I would have liked to, and since it doesn't have all the features I want it to have, I'm just going to release it here as a beta.
Some Screenshots:


Current Features:
- User friendly interface
- Open, save, and create new IMG archives for GTA San Andreas
(older version of the IMG format from GTA3 and Vice City are not
supported currently)
- Sort files by name, offset or size.
- View files in a detailed view, list view or iconic view
(Note: Iconic view might be slow for large files such as gta3.img)
- Search for files in archive directly from the toolbar.
- Automatically reuses space left over from previously deleted files
reducing the need to rebuild archives.
- Maintians the layout state of the archive in memory allowing you
to add/remove/delete files without committing directly to disk.
Nothing is saved until you say you want it to be saved!
- Drag and drop support from and to Explorer, and any other program
that supports drag and drop of files.
- Some limits to prevent accidental drag and drop of the all the files
in the archive.
Some things that are not supported yet... but planning to add support for them soon:
- Association with .IMG files
- In-place archive rebuilding
Download HereSource CodeAny suggestions, comments, etc are welcome

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This post has been edited by aru on Saturday, Sep 12 2009, 20:06