In this tutorial we create and upload annotations into a video item. Video annotations differ from image annotations since they span over frames, and need to be set with their scope.
This script uses module CV2, please use this page to install it.
Setup
import dtlpy as dl
if dl.token_expired():
dl.login()
project = dl.projects.get(project_name='project_name')
dataset = project.datasets.get(dataset_name='dataset_name')
item = dataset.items.get(filepath='/my_item.mp4')Create A Single annotation
Create a single annotations for a video item and upload it
annotation = dl.Annotation.new(item=item)
# Span the annotation over 100 frames. Change this or use a different approach based on your context
for i_frame in range(100):
# go over 100 frame
annotation.add_frame(annotation_definition=dl.Box(top=2 * i_frame,
left=2 * (i_frame + 10),
bottom=2 * (i_frame + 50),
right=2 * (i_frame + 100),
label="my-label"),
frame_num=i_frame, # set the frame for the annotation
)
# upload to platform
annotation.upload()Adding Multiple Annotations Using Annotation Builder
The following scripts demonstrate adding 10 annotations into each frame
# create annotation builder
builder = item.annotations.builder()
for i_frame in range(100):
# go over 100 frames
for i_detection in range(10):
# for each frame we have 10 different detections (location is just for the example)
builder.add(annotation_definition=dl.Box(top=2 * i_frame,
left=2 * i_detection,
bottom=2 * i_frame + 10,
right=2 * i_detection + 100,
label="my-label"),
# set the frame for the annotation
frame_num=i_frame,
# need to input the element id to create the connection between frames
object_id=i_detection + 1,
)
# Upload the annotations to platform
item.annotations.upload(builder)Read Frames of an Annotation
The following example reads all the frames an annotation exist in, e.g. the frame range an annotation spans over.
for annotation in item.annotations.list():
print(annotation.object_id)
for key in annotation.frames:
frame = annotation.frames[key]
print(frame.left, frame.right, frame.top, frame.bottom)Create Frame Snapshots from Video
One of Dataloop video utilities enables creating a frame snapshot from a video item every X frames (frame_interval).
You will need FFmpeg needs to be installed on your system using this official website
dl.utilities.Videos.video_snapshots_generator(item=item, frame_interval=30)Play An Item In Video Player
Play a video item with its annotations and labels with a video player
from dtlpy.utilities.videos.video_player import VideoPlayer
VideoPlayer(project_name=project_name,
dataset_name=dataset_name,
item_filepath=item_filepath)Show Annotations in a Specified Frame
import matplotlib.pyplot as plt
# Get from platform
annotations = item.annotations.list()
# Plot the annotations in frame 55 of the created annotations
frame_annotation = annotations.get_frame(frame_num=55)
plt.figure()
plt.imshow(frame_annotation.show())
plt.title(frame_annotation.label)
# Play video with the Dataloop video player
annotations.video_player()