Bdtjtk

In the code I have a list of tuples (start frame,end frame) and I want to take the whole list and create a new video file from it, the problem it takes only the last couple on the list

    import cv2



    vidPath = "wingate_18-11-18_3mp_25m_pm_4m(3).mp4"



    shotsPath = "new.avi"



    segRange = [(0,40),(50,100),(200,400)]  # a list of starting/ending frame indices pairs



    cap = cv2.VideoCapture(vidPath)



    fps = int(cap.get(cv2.CAP_PROP_FPS))



  size =

  (int(cap.get(cv2.CAP_PROP_FRAME_WIDTH)),int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT)))



   fourcc = int(cv2.VideoWriter_fourcc('X','V','I','D')) # XVID codecs





     for idx, (begFidx, endFidx) in enumerate(segRange):



         writer = cv2.VideoWriter(shotsPath, fourcc, fps, size)



         cap.set(cv2.CAP_PROP_POS_FRAMES, begFidx)



          ret = True  # has frame returned



          while (cap.isOpened() and ret and writer.isOpened()):



              ret, frame = cap.read()



              frame_number = cap.get(cv2.CAP_PROP_POS_FRAMES) - 1



              if frame_number < endFidx:



                  writer.write(frame)



              else:



                  break





 writer.release()

The new video was created from 200 to 400 , not including any frames before.
thanks very much for the help

It's because your writer overwrite the 1-40 and 50-100 by the last one 200-400 in the file name shotsPath=new.avi. Declare a new writer to new file with each segment.

[EDIT]

import cv2



vidPath = "1.MOV"

shotsPath = "new.avi"

segRange = [(0,40),(50,100),(200,400)]  # a list of starting/ending frame indices pairs

cap = cv2.VideoCapture(vidPath)

fps = int(cap.get(cv2.CAP_PROP_FPS))

size = (int(cap.get(cv2.CAP_PROP_FRAME_WIDTH)),int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT)))

fourcc = int(cv2.VideoWriter_fourcc('X','V','I','D')) # XVID codecs

#declare writer before the for loop

writer = cv2.VideoWriter(shotsPath, fourcc, fps, size)



for idx, (begFidx, endFidx) in enumerate(segRange):

    cap.set(cv2.CAP_PROP_POS_FRAMES, begFidx)

    ret = True  # has frame returned

    while (cap.isOpened() and ret and writer.isOpened()):

        ret, frame = cap.read()

        frame_number = cap.get(cv2.CAP_PROP_POS_FRAMES) - 1

        print(frame_number)

        if frame_number < endFidx:

            writer.write(frame)

        else:

            break

writer.release()



#Check how many frame that new.avi has

cap2 = cv2.VideoCapture("new.avi")

print(cap2.get(cv2.CAP_PROP_FRAME_COUNT))



>> 290 frames

The result is correct.