Slim down Final Cut Studio’s Media Content using HFS Compression

A full installation of Final Cut Studio 3 with all media content (for Motion, DVD Studio Pro, and Soundtrack Pro Loops) takes up around 40-50 GB of hard drive space.
How about regaining 5-10 GB of precious by enabling HFS compression for these folders? Since HFS compression is completely transparent, there are no adverse effects to expect (other than browsing the content libraries being almost unnoticeably slower).

To start, you’ll need a command-line tool called afsctool which can compress (and, amongst other features, decompress) folders using HFS compression. The command you’ll need to run is e.g. sudo afsctool -c -l -k -v -i -9 /Library/Application\ Support/Final\ Cut\ Studio. This compresses all files the given folder using the highest possible compression, verifies its results, prints out the names of files it is unable to compress, and outputs statistics once it’s done.

Some of the folders I compressed:
/Library/Application Support/Final Cut Studio/ (contains Motion and DVD Studio Pro templates): 22.5% compression savings
/Library/Application Support/LiveType/ (contains Motion’s LiveType fonts): 11.4% compression savings
/Library/Application Support/GarageBand/ (contains GarageBand’s  instruments and learning-to-play stuff): 14.3% compression savings
/Library/Application Support/iDVD/ (contains iDVD’s themes): 19.5% compression savings
/Library/Audio/Apple Loops/ (contains GarageBand’s and Soundtrack Pro’s loops): 4.1%
/Library/Audio/Impulse Responses/ (contains  Soundtrack Pro’s impulse response data): 41.3% compression savings

Looking at the compression savings: everything that contains high-quality video can be compressed by around 20%, while audio which is already heavily compressed only yields around 5%. The most amazing result though are the 40% by which the Impulse Responsed were compressed – apparently, these are uncompressed AIFF audio files and thus ideal for compression.

Obviously, your mileage may vary and I’m not responsible if you compress too much and break your system (I’m sure there is a reason why Apple didn’t compress all system files). However, compressing the iLife and Final Cut Studio media content appears safe, I haven’t noticed any unwanted side-effects and it seems well worth trying if you’d like to regain a few gigabytes.

4 thoughts on “Slim down Final Cut Studio’s Media Content using HFS Compression

  1. Julian Sincu

    So you said compression was completely transparent. What are the possible results if one was copying files into a compressed folder while power fails. Could the whole folder become unusable?
    As I understood from your results there is no way to do this with shipped tools from Snow Leopard. What reasons could Apple have not to include tools to use this function?

  2. Michael Kuron Post author

    Compression is applied file-by-file, i.e. if you copy something into a compressed folder, the file remains uncompressed. The only way to compress a file is by using something like afsctool.
    Regarding power failures during compression: the afsctool command I provided above includes a flag for verification – this makes afsctool first write the compressed data into the resource fork, then verify the written data, then set the compressed attribute and truncate the data fork.

    Actually, compression can also be done using Apple-provided tools: Snow Leopard’s ditto command supports the –hfsCompression flag. The advantage of using afsctool over ditto is that afsctool compresses the files in-place, while ditto is a file-copying tool.

  3. Stefan

    I’ve been trying to use afsctool, but for some reason, when I enter the suggested line above (sudo afsctool -c -l -k -v -i -9 /Library/Application\ Support/Final\ Cut\ Studio), it asks for my password, and when given, it returns Sudo: afsctool: Command not found

    Can you please help me ?

  4. Michael Kuron Post author

    Download afsctool from the link in the original post, extract it from the ZIP file and then do something like sudo /Users/yourname/Downloads/afsctool_34/afsctool -…..

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