Examples

videopypeline can be used to process any datatype. Nonetheless, its primary use is intended for videos. The examples below show some use cases. Refer to the Python-Notebook in this repository to see a more established usage example.

Linear pipeline

digraph Linear { "ReadVideoFile" -> "Rgb2Greyscale" "Rgb2Greyscale" -> "Crop" "Crop" -> "Smooth" "Smooth" -> "Print" "Print" -> "VideoWriter" }

import videopypeline as vpl

video_path = './path/to/video.mp4'
output_path = './path/to/output.mp4'

# Setup pipeline model
raw_video = videopypeline.generators.ReadVideoFile(video_path)
grey = videopypeline.functions.Rgb2Greyscale()(raw_video)
crop = videopypeline.functions.Crop((100, 200), (500, 500))(grey)
smooth1 = videopypeline.functions.Smooth(101)(crop)
stats = videopypeline.core.Action(lambda frame: print(frame.mean(), frame.std()))(smooth1)
writer = videopypeline.actions.VideoWriter(output_path, 30, aggregate=True, collect=False, verbose=True)(stats)

# Invoke pipeline
_ = writer()

Tree pipeline

digraph Tree { "ReadVideoFile1" -> "Rgb2Greyscale1" "Rgb2Greyscale1" -> "Smooth1" "ReadVideoFile2" -> "Rgb2Greyscale2" "Rgb2Greyscale2" -> "Smooth2" "Smooth1" -> "ImageDiff" "Smooth2" -> "ImageDiff" "ImageDiff" -> "VideoWriter" }

import videopypeline as vpl

video1_path = './path/to/video1.mp4'
video2_path = './path/to/video2.mp4'
output_path = './path/to/output.mp4'

# Setup pipeline model
raw_video1 = videopypeline.generators.ReadVideoFile(video1_path)
grey1 = videopypeline.functions.Rgb2Greyscale()(raw_video1)
smooth1 = videopypeline.functions.Smooth(101)(grey1)

raw_video2 = videopypeline.generators.ReadVideoFile(video2_path)
grey2 = videopypeline.functions.Rgb2Greyscale()(raw_video2)
smooth2 = videopypeline.functions.Smooth(101)(grey2)

# This node has two parents
diff = videopypeline.core.Function(lambda *frames: frames[0] - frames[1])([smooth1, smooth2])
writer = videopypeline.actions.VideoWriter(output_path, 30, aggregate=True, collect=False, verbose=True)(diff)

# Invoke pipeline
_ = writer()

Graph pipeline

import videopypeline as vpl

Filter pipeline

import videopypeline as vpl