FFMPEG with moviepy

Question

I'm working on something that concatenate videos and adds some titles on through moviepy.

As I saw on the web and on my on pc moviepy works on the CPU and takes a lot of time to save(render) a movie. Is there a way to improve the speed by running the writing of moviepy on GPU? Like using FFmpeg or something like this?

I didn't find an answer to that on the web, so I hope that some of you can help me. I tried using thread=4 and thread=16 but they are still very very slow and didn't change much.

My CPU is very strong (i7 10700k), but still, rendering on moviepy takes me for a compilation with a total of 8 minutes 40 seconds, which is a lot.

Any ideas?Thanks! the code doesnt realy matter but :

def Edit_Clips(self):

    clips = []

    time=0.0
    for i,filename in enumerate(os.listdir(self.path)):
        if filename.endswith(".mp4"):
            tempVideo=VideoFileClip(self.path + "\\" + filename)

            txt = TextClip(txt=self.arrNames[i], font='Amiri-regular',
                           color='white', fontsize=70)
            txt_col = txt.on_color(size=(tempVideo.w + txt.w, txt.h - 10),
                                   color=(0, 0, 0), pos=(6, 'center'), col_opacity=0.6)

            w, h = moviesize = tempVideo.size
            txt_mov = txt_col.set_pos(lambda t: (max(w / 30, int(w - 0.5 * w * t)),
                                                 max(5 * h / 6, int(100 * t))))

            sub=txt_mov.subclip(time,time+4)
            time = time + tempVideo.duration

            final=CompositeVideoClip([tempVideo,sub])

            clips.append(final)

    video = concatenate_videoclips(clips, method='compose')
    print("after")
    video.write_videofile(self.targetPath+"\\"+'test.mp4',threads=16,audio_fps=44100,codec = 'libx264')

Answer 1

in the past I was same problem and I solved that.

You need to use this command in your code ONLY one time.

video = CompositeVideoClip([clip1, clip2, clip3])

and export the video:

video.write_videofile(path_final_video)

while the video is export, moviepy will use all your cores.

Hope I helped :)

Answer 2

My gpu type is nvida, and I got 10 times faster with this command. you can try this:

echo y|ffmpeg -r 25 -i "a.mkv" -vcodec h264_nvenc "b.mp4"

If that not work, you can try else gpu accelerators:

-vcodec [accelerator_type]
# h264_nvenc
# hevc
# hevc_nvenc
# libx265

Run call in python(win 10):

input = 'a.mkv'
output = 'b.mp4'

call = "echo y|ffmpeg -r 25 -i \"%s\" -vcodec h264_nvenc  \"%s\"" % (input, output)
call

import os
os.system(call)

# subprocess.call or os.popen can get the call's return, 
# but if you want get the return at the same time,
# you should use this way:
import subprocess
pi= subprocess.Popen(call,shell=True,stdout=subprocess.PIPE)
for i in iter(pi.stdout.readline,'b'):
    print(i)

But this way is not work on moviepy's concat function because it's not support GPU. u'd better use ffmpeg to connact clips.

# concat_ffmpeg.bat
echo y|ffmpeg -i 1.mkv  -qscale 4 1.mpg
echo y|ffmpeg -i 2.mkv  -qscale 4 2.mpg
echo y|ffmpeg -i "concat:1.mpg|2.mpg" -c copy output.mp4

## sometimes can't use the [-c copy], u can try this and use GPU: 
# echo y|ffmpeg -i "concat:1.mpg|2.mpg" -vcodec h264_nvenc output.mp4

or Concatenating media files.

Reference:

How can I speed up moviepy by gpu? #923

ffmpeg 4.0 NVIDIA NVDEC-accelerated Support ? #790

Answer 3

I was able to significantly speed things up by trying different encoders.

You can type in the following command to get a list on your system:

ffmpeg -encoders

Then you can try each codec to see which one gives you the best result:

final.write_videofile(
        filename,
        threads=5,
        bitrate="2000k",
        audio_codec="aac",
        codec="h264_videotoolbox",
    )

For me h264_videotoolbox worked the best, but your system may be different. To my understanding you would have h264_nvenc if you were on an nvidia system.