Extract and assemble frames from a video using opencv used to create Stable Diffusion Video

README.md

Extract the frames

Create a virtual env

python -m venv myenv
# To activate the environment on Windows:
./myenv/Scripts/Activate.ps1
# To activate the environment on Linux:
source myenv/bin/activate

Install the required packages:

pip install -r requirements.txt

Make sure you have a input.mp4 in the same folder and start:

python extract.py

assemble.py

import cv2
import os
import glob
import re

# Define the output video file
output_file = "output.mp4"

# Get a list of all image files
img_files = glob.glob("sd_frames/*.jpg")

# Function to extract frame number from filename
def extract_number(filename):
    # This regular expression finds a number in the filename
    numbers = re.findall(r'\d+', filename)
    
    # If we found a number, return it as integer
    if numbers:
        return int(numbers[0])
    else:
        return None

# Sort the image files based on the frame number
img_files.sort(key=extract_number)

# Read the first image to get the size and color info
img = cv2.imread(img_files[0])

# Get image properties.
height, width, layers = img.shape

# Define the codec and create a VideoWriter object.
# FourCC is a 4-byte code used to specify the video codec.
fourcc = cv2.VideoWriter_fourcc(*'mp4v')  # or use 'XVID'
out = cv2.VideoWriter(output_file, fourcc, 30.0, (width, height))

for img_file in img_files:
    # Read the image file
    img = cv2.imread(img_file)

    # Write the frame to the video file
    out.write(img)

# After going through all images, release the video writer
out.release()

extract.py

import cv2
import os

# Define the name of the video file and output folder
video_file = "input.mp4"
output_folder = "extracted_frames"

# Create the output folder if it doesn't exist
if not os.path.exists(output_folder):
    os.makedirs(output_folder)

# Open the video file
cap = cv2.VideoCapture(video_file)

# Check if camera opened successfully
if not cap.isOpened(): 
    print("Error opening video stream or file")

frame_num = 0
while cap.isOpened():
    # Read a frame
    ret, frame = cap.read()

    # If we got a frame, save it to the output folder
    if ret:
        # Name the file with the frame number
        output_file = os.path.join(output_folder, f"frame_{frame_num}.jpg")
        
        # Save the frame as an image file
        cv2.imwrite(output_file, frame)

        frame_num += 1
    else:
        break

# After going through all frames, release the video capture object
cap.release()

# Close all the frames
cv2.destroyAllWindows()

requirements.txt

opencv-python
glob2