RAR Options
When using the Add to Archive dialog to
add files to a RAR archive, the following options are available:
- Compression level: This lets you set the compression
level used when adding the files to the archive. There are six compression
levels available, ranging from Store (which does no compression at
all and so is the fastest) to Best (which produces the highest level
of compression but takes longer to archive).
- Solid compression: This option enables solid
compression, which can improve compression when storing multiple similar
files. Compressing in solid mode imposes some restrictions on accessing the
archive. You may find it takes a long time to view or extract individual files
within solid archives because the data before the file you requested may need
to be decompressed first. Features such as thumbnails are generally disabled
within solid archives.
- Password: If you want to encrypt the files you are adding
to the archive, enter a password here. If the Mask password
option is on, the password you enter here will be hidden - and so for security
you must enter the password again in the Verify password
field. If you leave the Password field empty no encryption
will be performed.
- Verify password: If you have entered a password in the
Password field you need to enter the same password here as a
confirmation (unless Mask password is turned off).
- Mask password: If this option is on the passwords you
enter to encrypt the files you are adding will be masked (not displayed).
- Encrypt file names: As well as encrypting the file data
stored in the archive, this option will encrypt the file headers - so that the
names of the files in the archive are also encrypted.
- Send passwords to WinRAR via command-line: When Opus
invokes WinRAR (see note below) this option allows Opus to pass it the
password you entered above on the command line. This is more convenient - the
alternative is for WinRAR to prompt you for a password itself - but it may be
less secure, as the password you enter is visible in Task Manager for the
duration of the operation.
- Use multiple threads: If this option is on then Opus will
use multiple threads when adding to the archive - on a multi-CPU machine this
should make the compression process quicker.
- Store full file timestamps: This option causes the full
timestamp (created, last modified and last accessed) of the files to be stored
in the archive.
While Opus can read and decompress RAR archives by itself, creation and
modification of RAR archives requires you to have WinRAR installed on your system.
This is because RAR compression is a proprietary system that has not been
released by its creators for other developers to use and Opus is only able to
add files to RAR archives by invoking WinRAR in the background.