Open CV Codec FFMPEG Error fallback to use tag 0x7634706d/'mp4v'

Question

Doing a filter recording and all is fine. The code is running, but at the end the video is not saved as MP4. I have this error:

OpenCV: FFMPEG: tag 0x44495658/'XVID' is not supported with codec id 12 and format 'mp4 / MP4 (MPEG-4 Part 14)'
OpenCV: FFMPEG: fallback to use tag 0x7634706d/'mp4v'

Using a MAC and the code is running correctly, but is not saving. I tried to find more details about this error, but wasn't so fortunate. I use as editor Sublime. The code run on Atom tough but is giving this error:

OpenCV: FFMPEG: tag 0x44495658/'XVID' is not supported with codec id 12 and format 'mp4 / MP4 (MPEG-4 Part 14)'
OpenCV: FFMPEG: fallback to use tag 0x7634706d/'mp4v'
2018-05-28 15:04:25.274 Python[17483:2224774] AVF: AVAssetWriter status: Cannot create file

....

import numpy as np
import cv2
import random
from utils import CFEVideoConf, image_resize
import glob
import math


cap = cv2.VideoCapture(0)

frames_per_seconds = 24
save_path='saved-media/filter.mp4'
config = CFEVideoConf(cap, filepath=save_path, res='360p')
out = cv2.VideoWriter(save_path, config.video_type, frames_per_seconds, config.dims)


def verify_alpha_channel(frame):
    try:
        frame.shape[3] # looking for the alpha channel
    except IndexError:
        frame = cv2.cvtColor(frame, cv2.COLOR_BGR2BGRA)
    return frame


def apply_hue_saturation(frame, alpha, beta):
    hsv_image = cv2.cvtColor(frame, cv2.COLOR_BGR2HSV)
    h, s, v = cv2.split(hsv_image)
    s.fill(199)
    v.fill(255)
    hsv_image = cv2.merge([h, s, v])

    out = cv2.cvtColor(hsv_image, cv2.COLOR_HSV2BGR)
    frame = verify_alpha_channel(frame)
    out = verify_alpha_channel(out)
    cv2.addWeighted(out, 0.25, frame, 1.0, .23, frame)
    return frame


def apply_color_overlay(frame, intensity=0.5, blue=0, green=0, red=0):
    frame = verify_alpha_channel(frame)
    frame_h, frame_w, frame_c = frame.shape
    sepia_bgra = (blue, green, red, 1)
    overlay = np.full((frame_h, frame_w, 4), sepia_bgra, dtype='uint8')
    cv2.addWeighted(overlay, intensity, frame, 1.0, 0, frame)
    return frame


def apply_sepia(frame, intensity=0.5):
    frame = verify_alpha_channel(frame)
    frame_h, frame_w, frame_c = frame.shape
    sepia_bgra = (20, 66, 112, 1)
    overlay = np.full((frame_h, frame_w, 4), sepia_bgra, dtype='uint8')
    cv2.addWeighted(overlay, intensity, frame, 1.0, 0, frame)
    return frame


def alpha_blend(frame_1, frame_2, mask):
    alpha = mask/255.0 
    blended = cv2.convertScaleAbs(frame_1*(1-alpha) + frame_2*alpha)
    return blended


def apply_circle_focus_blur(frame, intensity=0.2):
    frame = verify_alpha_channel(frame)
    frame_h, frame_w, frame_c = frame.shape
    y = int(frame_h/2)
    x = int(frame_w/2)

    mask = np.zeros((frame_h, frame_w, 4), dtype='uint8')
    cv2.circle(mask, (x, y), int(y/2), (255,255,255), -1, cv2.LINE_AA)
    mask = cv2.GaussianBlur(mask, (21,21),11 )

    blured = cv2.GaussianBlur(frame, (21,21), 11)
    blended = alpha_blend(frame, blured, 255-mask)
    frame = cv2.cvtColor(blended, cv2.COLOR_BGRA2BGR)
    return frame


def portrait_mode(frame):
    cv2.imshow('frame', frame)
    gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
    _, mask = cv2.threshold(gray, 120,255,cv2.THRESH_BINARY)

    mask = cv2.cvtColor(mask, cv2.COLOR_GRAY2BGRA)
    blured = cv2.GaussianBlur(frame, (21,21), 11)
    blended = alpha_blend(frame, blured, mask)
    frame = cv2.cvtColor(blended, cv2.COLOR_BGRA2BGR)
    return frame


def apply_invert(frame):
    return cv2.bitwise_not(frame)

while(True):
    # Capture frame-by-frame
    ret, frame = cap.read()
    frame = cv2.cvtColor(frame, cv2.COLOR_BGR2BGRA) 
    #cv2.imshow('frame',frame)


    hue_sat = apply_hue_saturation(frame.copy(), alpha=3, beta=3)
    cv2.imshow('hue_sat', hue_sat)

    sepia = apply_sepia(frame.copy(), intensity=.8)
    cv2.imshow('sepia',sepia)

    color_overlay = apply_color_overlay(frame.copy(), intensity=.8, red=123, green=231)
    cv2.imshow('color_overlay',color_overlay)

    invert = apply_invert(frame.copy())
    cv2.imshow('invert', invert)

    blur_mask = apply_circle_focus_blur(frame.copy())
    cv2.imshow('blur_mask', blur_mask)

    portrait = portrait_mode(frame.copy())
    cv2.imshow('portrait',portrait)

    if cv2.waitKey(20) & 0xFF == ord('q'):
        break

# When everything done, release the capture
cap.release()
cv2.destroyAllWindows()

Answer 1

As suggested in the warning, you should change your codec to 'mp4v' (lower case) so that the error will disappear and you can save your video in mp4 format.