add extracting frames from video tutorial

Author: x4nth055

README.md

@@ -170,6 +170,7 @@ This is a repository of all the tutorials of [The Python Code](https://www.thepy
 -[How to Combine a Static Image with Audio in Python](https://www.thepythoncode.com/article/add-static-image-to-audio-in-python). ([code](python-for-multimedia/add-photo-to-audio))
 -[How to Concatenate Video Files in Python](https://www.thepythoncode.com/article/concatenate-video-files-in-python). ([code](python-for-multimedia/combine-video))
 -[How to Concatenate Audio Files in Python](https://www.thepythoncode.com/article/concatenate-audio-files-in-python). ([code](python-for-multimedia/combine-audio))
+-[How to Extract Frames from Video in Python](https://www.thepythoncode.com/article/extract-frames-from-videos-in-python). ([code](python-for-multimedia/extract-frames-from-video))
 
 
 For any feedback, please consider pulling requests.

python-for-multimedia/extract-frames-from-video/README.md

@@ -0,0 +1,4 @@
+# [How to Extract Frames from Video in Python](https://www.thepythoncode.com/article/extract-frames-from-videos-in-python)
+To run this:
+-`pip3 install -r requirements.txt`
+- Use `extract_frames_opencv.py` for using OpenCV to extract frames, or use `extract_frames_moviepy.py` for using MoviePy library.

python-for-multimedia/extract-frames-from-video/extract_frames_moviepy.py

@@ -0,0 +1,47 @@
+frommoviepy.editorimportVideoFileClip
+importnumpyasnp
+importos
+fromdatetimeimporttimedelta
+
+# i.e if video of duration 30 seconds, saves 10 frame per second = 300 frames saved in total
+SAVING_FRAMES_PER_SECOND=10
+
+defformat_timedelta(td):
+"""Utility function to format timedelta objects in a cool way (e.g 00:00:20.05) 
+ omitting microseconds and retaining milliseconds"""
+result=str(td)
+try:
+result, ms=result.split(".")
+exceptValueError:
+returnresult+".00".replace(":", "-")
+ms=int(ms)
+ms=round(ms/1e4)
+returnf"{result}.{ms:02}".replace(":", "-")
+
+
+defmain(video_file):
+# load the video clip
+video_clip=VideoFileClip(video_file)
+# make a folder by the name of the video file
+filename, _=os.path.splitext(video_file)
+filename+="-moviepy"
+ifnotos.path.isdir(filename):
+os.mkdir(filename)
+
+# if the SAVING_FRAMES_PER_SECOND is above video FPS, then set it to FPS (as maximum)
+saving_frames_per_second=min(video_clip.fps, SAVING_FRAMES_PER_SECOND)
+# if SAVING_FRAMES_PER_SECOND is set to 0, step is 1/fps, else 1/SAVING_FRAMES_PER_SECOND
+step=1/video_clip.fpsifsaving_frames_per_second==0else1/saving_frames_per_second
+# iterate over each possible frame
+forcurrent_durationinnp.arange(0, video_clip.duration, step):
+# format the file name and save it
+frame_duration_formatted=format_timedelta(timedelta(seconds=current_duration)).replace(":", "-")
+frame_filename=os.path.join(filename, f"frame{frame_duration_formatted}.jpg")
+# save the frame with the current duration
+video_clip.save_frame(frame_filename, current_duration)
+
+
+if__name__=="__main__":
+importsys
+video_file=sys.argv[1]
+main(video_file)

python-for-multimedia/extract-frames-from-video/extract_frames_opencv.py

@@ -0,0 +1,80 @@
+fromdatetimeimporttimedelta
+importcv2
+importnumpyasnp
+importos
+
+# i.e if video of duration 30 seconds, saves 10 frame per second = 300 frames saved in total
+SAVING_FRAMES_PER_SECOND=10
+
+defformat_timedelta(td):
+"""Utility function to format timedelta objects in a cool way (e.g 00:00:20.05) 
+ omitting microseconds and retaining milliseconds"""
+result=str(td)
+try:
+result, ms=result.split(".")
+exceptValueError:
+returnresult+".00".replace(":", "-")
+ms=int(ms)
+ms=round(ms/1e4)
+returnf"{result}.{ms:02}".replace(":", "-")
+
+
+defget_saving_frames_durations(cap, saving_fps):
+"""A function that returns the list of durations where to save the frames"""
+s= []
+# get the clip duration by dividing number of frames by the number of frames per second
+clip_duration=cap.get(cv2.CAP_PROP_FRAME_COUNT) /cap.get(cv2.CAP_PROP_FPS)
+# use np.arange() to make floating-point steps
+foriinnp.arange(0, clip_duration, 1/saving_fps):
+s.append(i)
+returns
+
+
+defmain(video_file):
+filename, _=os.path.splitext(video_file)
+filename+="-opencv"
+# make a folder by the name of the video file
+ifnotos.path.isdir(filename):
+os.mkdir(filename)
+# read the video file 
+cap=cv2.VideoCapture(video_file)
+# get the FPS of the video
+fps=cap.get(cv2.CAP_PROP_FPS)
+# if the SAVING_FRAMES_PER_SECOND is above video FPS, then set it to FPS (as maximum)
+saving_frames_per_second=min(fps, SAVING_FRAMES_PER_SECOND)
+# get the list of duration spots to save
+saving_frames_durations=get_saving_frames_durations(cap, saving_frames_per_second)
+# start the loop
+count=0
+whileTrue:
+is_read, frame=cap.read()
+ifnotis_read:
+# break out of the loop if there are no frames to read
+break
+# get the duration by dividing the frame count by the FPS
+frame_duration=count/fps
+try:
+# get the earliest duration to save
+closest_duration=saving_frames_durations[0]
+exceptIndexError:
+# the list is empty, all duration frames were saved
+break
+ifframe_duration>=closest_duration:
+# if closest duration is less than or equals the frame duration, 
+# then save the frame
+frame_duration_formatted=format_timedelta(timedelta(seconds=frame_duration))
+cv2.imwrite(os.path.join(filename, f"frame{frame_duration_formatted}.jpg"), frame) 
+# drop the duration spot from the list, since this duration spot is already saved
+try:
+saving_frames_durations.pop(0)
+exceptIndexError:
+pass
+# increment the frame count
+count+=1
+
+
+
+if__name__=="__main__":
+importsys
+video_file=sys.argv[1]
+main(video_file)

python-for-multimedia/extract-frames-from-video/requirements.txt

@@ -0,0 +1,2 @@
+python-opencv
+moviepy