ibllib.io.video

Functions for fetching video frames, meta data and file locations

Functions

assert_valid_label	Raises a value error is the provided label is not supported.
get_video_frame	Obtain numpy array corresponding to a particular video frame in video_path
get_video_frames_preload	Obtain numpy array corresponding to a particular video frame in video.
get_video_meta	Return a bunch of video information with the fields ('length', 'fps', 'width', 'height', 'duration', 'size')
label_from_path	Return the video label, e.g.. 'left', 'right' or 'body'.
url_from_eid	Return the video URL(s) for a given eid

Classes

VideoStreamer

Provides a wrapper to stream a video from a password protected HTTP server using opencv

class VideoStreamer(url_vid)

Bases: object

Provides a wrapper to stream a video from a password protected HTTP server using opencv

get_frame(frame_index)

get_video_frame(video_path, frame_number)

Obtain numpy array corresponding to a particular video frame in video_path

Parameters:

• video_path – local path to mp4 file

• frame_number – video frame to be returned

Returns:

numpy array corresponding to frame of interest. Dimensions are (w, h, 3)

get_video_frames_preload(vid, frame_numbers=None, mask=Ellipsis, as_list=False, func=<function <lambda>>, quiet=False)

Obtain numpy array corresponding to a particular video frame in video. Fetching and returning a list is about 33% faster but may be less memory controlled. NB: Any gain in speed will be lost if subsequently converted to array.

Parameters:

• vid – URL or local path to mp4 file or cv2.VideoCapture instance.

• frame_numbers – video frames to be returned. If None, return all frames.

• mask – a logical mask or slice to apply to frames

• as_list – if true the frames are returned as a list, this is faster but may be less

memory efficient :param func: Function to be applied to each frame. Applied after masking if applicable. :param quiet: if true, suppress frame loading progress output. :return: numpy array corresponding to frame of interest, or list if as_list is True. Default dimensions are (n, w, h, 3) where n = len(frame_numbers)

Example - Load first 1000 frames, keeping only the first colour channel:

frames = get_video_frames_preload(vid, range(1000), mask=np.s_[:, :, 0])

get_video_meta(video_path, one=None)

Return a bunch of video information with the fields (‘length’, ‘fps’, ‘width’, ‘height’, ‘duration’, ‘size’)

Parameters:

• video_path – A path to the video. May be a file path or URL.

• one – An instance of ONE

Returns:

A Bunch of video mata data

url_from_eid(eid, label=None, one=None)

Return the video URL(s) for a given eid

Parameters:

• eid – The session id

• label – The video label (e.g. ‘body’) or a tuple thereof

• one – An instance of ONE

Returns:

The URL string if the label is a string, otherwise a dict of urls with labels as keys

label_from_path(video_name)

Return the video label, e.g.. ‘left’, ‘right’ or ‘body’

Parameters:

video_name – A file path, URL or file name for the video

Returns:

The string label or None if the video doesn’t match

assert_valid_label(label)

Raises a value error is the provided label is not supported.

Parameters:

label – A video label to verify

Returns:

the label in lowercase