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Merge audio (m4s) segments into one

I recently started learning Laravel, and currently watching an online course. Online courses are fine, but I like to have local copies, so I'm trying to download/merge segmented audio from Laracasts: Laravel 8 From Scratch series.
I've written some scripts (in Python) that does the following:
Download the master.json
Read master.json and download audio segments
Merge the segments into a single file (the file is not playable yet)
Process the audio file via ffmpeg (now it's playable, but has issues)
I think there's a problem with the step 3 and/or 4.
In step/script 3, I create a new file, and add the contents of the segments to the file in binary.
Then (step/script 4), run a ffmpeg command in python: ffmpeg -i merged-file.mp4 -c copy processed-file.mp4
However, the final file doesn't work/play as expected. There's a delay in the beginning, and some parts seem to be cut off/skipped.
There are three possibilities:
Segment files are problematic (not likely?)
I'm doing the merging wrong
I'm doing the ffmpeg processing wrong
Can someone guide me here?
The issues/colored parts in the ffmpeg output are:
...
[mov,mp4,m4a,3gp,3g2,mj2 # 000001cfbc0de780] could not find corresponding track id 2
[mov,mp4,m4a,3gp,3g2,mj2 # 000001cfbc0de780] could not find corresponding trex (id 2)
...
[aac # 000001cfbc0f0380] Number of bands (31) exceeds limit (6).
...
[mp4 # 000001cfbc20ecc0] track 0: codec frame size is not set
...
[mp4 # 000001cfbc20ecc0] Non-monotonous DTS in output stream 0:0; previous: 318318, current: 286286; changing to 318319. This may result in incorrect timestamps in the output file.
...
Everything required for a test case is located in GitHub (akinuri/dump/m4s-segments/). Screenshot of the contents:
Note: there are two types/formats of audio in the master.json: mp42 and dash. dash works as expected, and seem to be used in limited videos/courses. On the other hand, mp42 appears more. So I need a way to make mp42 work.

MoviePy - getting progress bar values

I am running a python script which converts a video file to a audio clip using moviepy.
def convert(mp3_file,mp4_file):
videoclip = VideoFileClip(mp4_file)
audioclip = videoclip.audio
audioclip.write_audiofile(mp3_file)
audioclip.close()
videoclip.close()
I found out that Moviepy uses a library called Proglog to print a command line progress bar.
How do I get these process completion percentage values?

WARNING: Bruteforce ahead!
It is possible, however, moviepy has no official method to do this.
We can get the progress inside the source code of the module
we need to edit the module code and follow the steps. [This is for ubuntu linux]
Step 1 -
go to the ffmpg_writter.py [usually in /home/anipr/.local/lib/python3.10/site-packages/moviepy/video/io/ffmpeg_writer.py]
Step 2 -
go to line 221 and add calculate the percentage based on duration - get_the_persentage_of_progress = (t/clip.duration)*100
Step - 3
do anything with the variable get_the_persentage_of_progress
however, getting the variable back to our original code is a bit tricky.
here are a few ideas -
write it to a file.txt
insert into database
[let me know in comments if any better idea]

Fonts not found

I am trying to add simple text to a mp4 file. I have the mp4 file and I am using moviepy to add the text clip, however, I am continually running into errors.
My code:
import moviepy.editor as mpy
video_name='Test.mp4'
video = mpy.VideoFileClip('test_movie.mp4')
text = mpy.TextClip("Test", font="Arial", fontsize=40, color='white')
text = text.set_position('upper left').set_duration(video.duration)
test = mpy.CompositeVideoClip([video, text])
test.write_videofile('{}.mp4'.format(video_name))
And here is the error:
IOError: MoviePy Error: creation of None failed because of the following error:
convert: delegate library support not built-in '/Library/Fonts//Arial.ttf' (Freetype) # warning/annotate.c/RenderFreetype/1847.
convert: no decode delegate for this image format `PNG' # error/constitute.c/ReadImage/512.
convert: no images defined `PNG32:/var/folders/l3/m81nh88n57s9ck30_fqd09cmcfj06p/T/tmp06GxjE.png' # error/convert.c/ConvertImageCommand/3275.
.
.This error can be due to the fact that ImageMagick is not installed on your computer, or (for Windows users) that you didn't specify the path to the ImageMagick binary in file conf.py, or that the path you specified is incorrect
ImageMagick is installed on my system and I have been through a few threads on here but nothing has pointed me in the right direction. My font library is not empty and I do not know what it is having this issue. Any help would be greatly appreciated. I am on a Mac and using Spyder for a GUI.

Try to install ImageMagick from their website.
If the problem still there, find the moviepy/config_defaults.py and after the last line add:
IMAGEMAGICK_BINARY = "C:\\Program Files\\ImageMagick_VERSION\\convert.exe

Moviepy unable to read duration of file

I have been using Moviepy to combine several shorter video files into hour long files. Some small files are "broken", they contain video but was not completed correctly (i.e. they play with VLC but there is no duration and you cannot skip around in the video).
I noticed this issue when I try to create a clip using VideoFileClip(file) function. The error that comes up is:
MoviePy error: failed to read the duration of file
Is there a way to still read the "good" frames from this video file and then add them to the longer video?
UPDATE
To clarify, my issue specifically is with the following function call:
clip = mp.VideoFileClip("/home/test/"+file)
Stepping through the code it seems to be an issue when checking the duration of the file in ffmpeg_reader.py where it looks for the duration parameter in the video file. However, since the file never finished recording properly this information is missing. I'm not very familiar with the way video files are structured so I am unsure of how to proceed from here.

You're correct. This issue arises commonly when the video duration info is missing from the file.
Here's a thread on the issue: GitHub moviepy issue 116
One user proposed the solution of using MP4Box to convert the video using this guide: RASPIVID tutorial
The final solution that worked for me involved specifying the path to ImageMagick's binary file as WDBell mentioned in this post.
I had the path correctly set in my environment variables, but it wasn't till I specificaly defined it in config_defaults.py that it started working:

I solved it in a simpler way, with the help of VLC I converted the file to the forma MPEG4 xxx TV/device,
and you can now use your new file with python without any problem
xxx = 720p or
xxx = 1080p
everything depends on your choice on the output format
I already answered this question on the blog: https://github.com/Zulko/moviepy/issues/116

This issue appears when VideoFileClip(file) function from moviepy it looks for the duration parameter in the video file and it's missing. To avoid this (in those corrupted files cases) you should make sure that the total frames parameter is not null before to shoot the function: clip = mp.VideoFileClip("/home/test/"+file)
So, I handled it in a simpler way using cv2.
The idea:
find out the total frames
if frames is null, then call the writer of cv2 and generate a temporary copy of the video clip.
mix the audio from the original video with the copy.
replace the original video and delete copy.
then call the function clip = mp.VideoFileClip("/home/test/"+file)
Clarification: Since OpenCV VideoWriter does not encode audio, the new copy will not contain audio, so it would be necessary to extract the audio from the original video and then mix it with the copy, before replacing it with the original video.
You must import cv2
import cv2
And then add something like this in your code before the evaluation:
cap = cv2.VideoCapture("/home/test/"+file)
frames = int(cap.get(cv2.CAP_PROP_FRAME_COUNT))
fps = int(cap.get(cv2.CAP_PROP_FPS))
print(f'Checking Video {count} Frames {frames} fps: {fps}')
This will surely return 0 frames but should return at least framerate (fps).
Now we can set the evaluation to avoid the error and handle it making a temp video:
if frames == 0:
print(f'No frames data in video {file}, trying to convert this video..')
writer = cv2.VideoWriter("/home/test/fixVideo.avi", cv2.VideoWriter_fourcc(*'DIVX'), int(cap.get(cv2.CAP_PROP_FPS)),(int(cap.get(cv2.CAP_PROP_FRAME_WIDTH)),int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT))))
while True:
ret, frame = cap.read()
if ret is True:
writer.write(frame)
else:
cap.release()
print("Stopping video writer")
writer.release()
writer = None
break
Mix the audio from the original video with the copy. I have created a function for this:
def mix_audio_to_video(pathVideoInput, pathVideoNonAudio, pathVideoOutput):
videoclip = VideoFileClip(pathVideoInput)
audioclip = videoclip.audio
new_audioclip = CompositeAudioClip([audioclip])
videoclipNew = VideoFileClip(pathVideoNonAudio)
videoclipNew.audio = new_audioclip
videoclipNew.write_videofile(pathVideoOutput)
mix_audio_to_video("/home/test/"+file, "/home/test/fixVideo.avi", "/home/test/fixVideo.mp4")
replace the original video and delete copys:
os.replace("/home/test/fixVideo.mp4", "/home/test/"+file)

I had the same problem and I have found the solution.
I don't know why but if we enter the path in this method path = r'<path>' instead of ("F:\\path") we get no error.

Just click on the
C:\Users\gladi\AppData\Local\Programs\Python\Python311\Lib\site-packages\moviepy\video\io\ffmpeg_reader.py
and delete the the code and add this one
Provided by me in GITHUB - https://github.com/dudegladiator/Edited-ffmpeg-for-moviepy

clip1=VideoFileClip('path')
c=clip1.duration
print(c)

OpenCV + python -- grab frames from a video file

I can't seem to capture frames from a file using OpenCV -- I've compiled from source on Ubuntu with all the necessary prereqs according to: http://opencv.willowgarage.com/wiki/InstallGuide%20%3A%20Debian
#!/usr/bin/env python
import cv
import sys
files = sys.argv[1:]
for f in files:
capture = cv.CaptureFromFile(f)
print capture
print cv.GetCaptureProperty(capture, cv.CV_CAP_PROP_FRAME_WIDTH)
print cv.GetCaptureProperty(capture, cv.CV_CAP_PROP_FRAME_HEIGHT)
for i in xrange(10000):
frame = cv.QueryFrame(capture)
if frame:
print frame
Output:
ubuntu#local:~/opencv$ ./test.py bbb.avi
<Capture 0xa37b130>
0.0
0.0
The frames are always None...
I've transcoded a video file to i420 format using:
mencoder $1 -nosound -ovc raw -vf format=i420 -o $2
Any ideas?

You don't have the gstreamer-ffmpeg or gsteamer-python or gsteamer-python-devel packages installed. I installed all three of them. and the exact same problem was resolved.

I'm using OpenCV 2.2.0, compiled on Ubuntu from source. I can confirm that the source code you provided works as expected. So the problem is somewhere else.
I couldn't reproduce your problem using mencoder (installing it is a bit of a problem on my machine) so I used ffmpeg to wrap a raw video in the AVI container:
ffmpeg -s cif -i ~/local/sample-video/foreman.yuv -vcodec copy foreman.avi
(foreman.yuv is a standard CIF image sequence you can find on the net if you look around).
Running the AVI from ffmpeg through your source gives this:
misha#misha-desktop:~/Desktop/stackoverflow$ python ocv_video.py foreman.avi
<Capture 0xa71120>
352.0
288.0
<iplimage(nChannels=3 width=352 height=288 widthStep=1056 )>
<iplimage(nChannels=3 width=352 height=288 widthStep=1056 )>
...
So things work as expected. What you should check:
Do you get any errors on standard output/standard error? OpenCV uses ffmpeg libraries to read video files, so be on the lookout for informative messages. Here's what happens if you try to play a RAW video file without a container (sounds similar to your problem):
error:
misha#misha-desktop:~/Desktop/stackoverflow$ python ocv_video.py foreman.yuv
[IMGUTILS # 0x7fff37c8d040] Picture size 0x0 is invalid
[IMGUTILS # 0x7fff37c8cf20] Picture size 0x0 is invalid
[rawvideo # 0x19e65c0] Could not find codec parameters (Video: rawvideo, yuv420p)
[rawvideo # 0x19e65c0] Estimating duration from bitrate, this may be inaccurate
GStreamer Plugin: Embedded video playback halted; module decodebin20 reported: Your GStreamer installation is missing a plug-in.
<Capture 0x19e3130>
0.0
0.0
Make sure your AVI file actually contains the required information to play back the video. At a minimum, this should be the frame dimensions. RAW video typically doesn't contain any information besides the actual pixel data, so knowing the frame dimensions and FPS is required. You can wrong-guess the FPS and still get a viewable video, but if you get the dimensions wrong, the video will be unviewable.
Make sure the AVI file you're trying to open is actually playable. Try ffplay file.avi -- if that fails, then the problem is likely to be with the file. Try using ffmpeg to transcode instead of mencoder.
Make sure you can play other videos, using the same method as above. If you can't, then it's likely that your ffmpeg install is broken.