

# Detecting Custom Labels in videos
<a name="ex-video-extraction"></a>

The following example shows how you can use `DetectCustomLabels` with frames extracted from a video. The code has been tested with video files in *mov* and *mp4* format.

**Using `DetectCustomLabels` with captured frames**

1. If you haven't already done so, install and configure the AWS CLI and the AWS SDKs. For more information, see [Step 4: Set up the AWS CLI and AWS SDKs](su-awscli-sdk.md).

1. Make sure you have `rekognition:DetectCustomLabels` and `AmazonS3ReadOnlyAccess` permissions. For more information, see [Step 4: Set up the AWS CLI and AWS SDKs](su-awscli-sdk.md).

1. Use the following example code. Change the value of `videoFile` to the name of a video file. Change the value of `projectVersionArn` to the Amazon Resource Name (ARN) of your Amazon Rekognition Custom Labels model. 

   ```
   # Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
   # SPDX-License-Identifier: Apache-2.0
   
   """
   Purpose
   Shows how to analyze a local video with an Amazon Rekognition Custom Labels model.
   """
   import argparse
   import logging
   import json
   import math
   import cv2
   import boto3
   
   from botocore.exceptions import ClientError
   
   logger = logging.getLogger(__name__)
   
   
   def analyze_video(rek_client, project_version_arn, video_file):
       """
       Analyzes a local video file with an Amazon Rekognition Custom Labels model.
       Creates a results JSON file based on the name of the supplied video file.
       :param rek_client: A Boto3 Amazon Rekognition client.
       :param project_version_arn: The ARN of the Custom Labels model that you want to use.
       :param video_file: The video file that you want to analyze.
       """
       
       custom_labels = []
       cap = cv2.VideoCapture(video_file)
       frame_rate = cap.get(5)  # Frame rate.
       while cap.isOpened():
           frame_id = cap.get(1)  # Current frame number.
           print(f"Processing frame id: {frame_id}")
           ret, frame = cap.read()
           if ret is not True:
               break
           if frame_id % math.floor(frame_rate) == 0:
               has_frame, image_bytes = cv2.imencode(".jpg", frame)
   
               if has_frame:
                   response = rek_client.detect_custom_labels(
                       Image={
                           'Bytes': image_bytes.tobytes(),
                       },
                       ProjectVersionArn=project_version_arn
                   )
   
               for elabel in response["CustomLabels"]:
                   elabel["Timestamp"] = (frame_id/frame_rate)*1000
                   custom_labels.append(elabel)
   
       print(custom_labels)
   
       with open(video_file + ".json", "w", encoding="utf-8") as f:
           f.write(json.dumps(custom_labels))
   
       cap.release()
   
   
   def add_arguments(parser):
       """
       Adds command line arguments to the parser.
       :param parser: The command line parser.
       """
   
       parser.add_argument(
           "project_version_arn", help="The ARN of the model that you want to use."
       )
   
       parser.add_argument(
           "video_file", help="The local path to the video that you want to analyze."
       )
   
   
   def main():
   
       logging.basicConfig(level=logging.INFO,
                           format="%(levelname)s: %(message)s")
   
       try:
           # Get command line arguments.
           parser = argparse.ArgumentParser(usage=argparse.SUPPRESS)
           add_arguments(parser)
           args = parser.parse_args()
   
           session = boto3.Session(profile_name='custom-labels-access')
           rekognition_client = session.client("rekognition")
   
           analyze_video(rekognition_client,
                        args.project_version_arn, args.video_file)
   
       except ClientError as err:
           print(f"Couldn't analyze video: {err}")
   
   
   if __name__ == "__main__":
       main()
   ```