Repository

The Repository class allows to read and write to bb_binary data stores.

The bb_binary data is splitted into several files that are organized in subfolders via date and time. A Repository manages these bb_binary datafiles and provides methods to add new FrameContainer, or iterate through Frame.

This class provides performant access to a bb_binary data store but you will have to parse the data by yourself. You might use some helpers from Parsing.

load_frame_container(fname)

Loads FrameContainer from this filename.

class Repository(root_dir, minute_step=None)

Bases: object

The Repository class manages multiple bb_binary files. It creates a directory layout that enables fast access by the timestamp.

add(frame_container)

Adds the frame_container of type FrameContainer to the repository.

open(timestamp, cam_id)

Finds and load the FrameContainer that matches the timestamp and cam_id.

find(ts, cam=None)

Returns all files that includes detections to the given timestamp ts.

Todo

UTC timestamps! Generall

iter_fnames(begin=None, end=None, cam=None)

Returns a generator that yields filenames in sorted order.

From begin to end.

Parameters:

• begin (Optional timestamp) – The first filename contains at least one frame with a timestamp greater or equal to begin. If begin is not set, it will start with the earliest file.
• end (Optional timestamp) – The last filename contains at least one frame with a timestamp smaller then end. If not set, it will continue until the last file.
• cam (Optional int) – Only yield filenames with this cam id.

Example:

Files:        A     B     C        D     E
Frames:    |-----|-----|-----|  |-----|-----|
                ⬆          ⬆
              begin       end

This should return the files A, B and C. If begin and end are None, then all will be yield.

iter_frames(begin=None, end=None, cam=None)

Yields frames in sorted order. From begin to end.

Parameters:

• begin (Optional timestamp) – select frames with begin <= timestamp.
• with smallest timestamp in repository if not set. (Starts) –
• end (Optional timestamp) – select frames with timestamp < end.
• with biggest timestamp in repository if not set. (Ends) –
• cam (Optional int) – only yield filenames with this cam id.

Returns:

tuple containing:

iterator (iterable): iterator with Frames FrameContainer (FrameContainer): the corresponding FrameContainer for each frame.

Return type:

(tuple)

class TimeInterval(begin, end)

Bases: object

Helper class to represent time intervals.

in_interval(dt)