AstroFloppyImage is a free tool for extracting the content of floppy images to the temp directory and creating new floppy images from the content of the temp directory. If you want to extract a floppy image, select "extract img file", choose a file and check the folder temp/files for the files. If you want to create a floppy image, delete the content of temp/files and temp/reservedarea.img, put your files there and select "create img file".
Floppy images can be used with emulators like hatari 1.8.0 (, VMWare Player ( and VirtualBox ( hatari 1.8.0 needs images with the extension .st. If the extension is different, the emulator crashes. UltraISO ( needs extensions like .img, .ima and .flp. Otherwise it also crashes. If you rename your AstroFloppyImage file, you can use it with both programs.
If you extract a floppy image, the boot sector and the reserved area following it are copied to temp/reservedarea.img. If you don't delete it, its parameters are used for the next created img file, also if you selected another parameter script file. You can replace temp/reservedarea.img by your own image of the reserved area. If you extract a floppy image and a volume label is found, it is copied to temp/volumelabel.ini, where the volume label string can be changed. If you create a new floppy image, the file temp/volumelabel.ini is searched and its content used as volume label, if it exists. The volume label is stored as a directory entry and the boot sector volume label bytes are not changed. This is slightly incompatible to the ATARI ST, where you see a folder in the root directory named like the volume label and no disk label.
If you want to create new 1.44 MB or 720 KB floppy images, you should delete temp/reservedarea.img and the content of temp/files, edit volumelabel.ini and place your files in temp/files. Click "select parameter script file" and choose floppyparameterscript.ini for a 1.44 MB disk and floppyparameterscript720.ini for a 720 KB disk. You can choose a destination file after clicking "create img file". The 720 KB files should be named .st and the others .img or .ima. If you want to create a disk image with more special parameters, you should copy floppyparameterscript.ini or floppyparameterscript720.ini and edit its parameters.

If you create a disk image with files from the temp directory and the size of the disk image is exceeded, a number of reserved sectors, which was greater than the total number of sectors, is displayed in the results text area. This number is not the number of sectors needed for your disk image, but the first reservation of disk space, which exceeded the disk image size. The next reservations are skipped, because there could be very slow calculations, if there was a very big file in the files folder.

AstroFloppyImage is written in JAVA. The program is compatible to the filenames of Windows and Linux unlike many other Astro Solutions JAVA applications (except of the games), which use Windows filenames.

A free small tool for splitting files in smaller parts for multiple floppy disks or CD-ROMs is included in the subfolder FileSplitter.

It took five days to write the code of AstroFloppyImage. There is a version for JAVA 1.1.8 and JView, which uses a deprecated JAVA API and a Swing version for JAVA 1.8, which doesn't use a deprecated JAVA API. The Swing version can be found in the subfolder AstroFloppyImageSwing.