A Python library for parsing frame ranges.
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A Python library for parsing frame ranges and file sequences based on a similar library found in Katana.

Frame Range Shorthand

Support for:

  • Standard: 1-10
  • Comma Delimited: 1-10,10-20
  • Chunked: 1-100x5
  • Filled: 1-100y5
  • Staggered: 1-100:3 (1-100x3, 1-100x2, 1-100)
  • Negative frame numbers: -10-100
  • Padding: #=4 padded, @=single pad
  • Printf Syntax Padding: %04d=4 padded, %01d=1 padded


A FrameSet wraps a sequence of frames in a list list container.

Iterate a FrameSet

fs = fileseq.FrameSet("1-5")
for f in fs:
  print f

Access Frames

Using Indices:

>>> fs = fileseq.FrameSet("1-100:8")
>>> fs[0] # First frame.
>>> fs[-1] # Last frame.

Using Convenience Methods:

>>> fs = fileseq.FrameSet("1-100:8")
>>> fs.start() # First frame.
>>> fs.end() # Last frame.


Instantiate from String


Format Path for VFX Software

Using FileSequence.format Method:

>>> seq = fileseq.FileSequence("/foo/bar.1-10#.exr")
>>> seq.format(template='{dirname}{basename}{padding}{extension}') 


>>> seq = fileseq.FileSequence("/foo/bar.1-10#.exr")
>>> ''.join([seq.dirname(), seq.basename(), '%0{}d'.format(len(str(seq.end()))), seq.extension()])

Get List of File Paths

>>> seq = fileseq.FileSequence("/foo/bar.1-10#.exr")
>>> [seq[idx] for idx, fr in enumerate(seq.frameSet())]

Finding Sequences on Disk

Check a Directory for All Existing Sequences

seqs = fileseq.findSequencesOnDisk("/show/shot/renders/bty_foo/v1")

Check a Directory for One Existing Sequence.

  • Use a '@' or '#' where you might expect to use '*' for a wildcard character.
  • For this method, it doesn't matter how many instances of the padding character you use, it will still find your sequence.







Changes in versions >= 1.0.0

From version 1.0.0, a FrameSet allows all the normal Set operations. It is now an immutable and hashable object in its own right, as well. This means that the order and contents are immutable values internally (a tuple and a frozenset, respectively), and that the FrameSet itself can be used as a key in a dictionary.

This also means that the null FrameSet (FrameSet('')) is a valid object, and something you should expect to receive back from any Set operations that would result in an empty return value. This brings the caveat that the FrameSet.start and FrameSet.end methods on a null FrameSet will raise an IndexError if called.

To help avoid confusion, a FrameSet.is_null attribute has been added in 1.0.1, which you can check before calling those methods.