🔒 Convert images (frames) to a video with ffmpeg or cv2 | Python | Page 1

neon lagoon Jan 31, 2025, 9:25 PM

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hello!
i am trying to make a super generic lightweight screen recorder with python
i have managed to make the frame saving part, now comes the part where i shove all of them together into a video

i've tried cv2 (!pypi opencv-python) but the resulting video plays faster (more than 2x) than i wanted it to

i'm open to also using any other library that can do this for me

i split the project into two files
recorder: https://paste.pythondiscord.com/BH6Q
constructor: https://paste.pythondiscord.com/U6SA

white charmBOT Jan 31, 2025, 9:25 PM

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neon lagoon hello! i am trying to make a super generic lightweight screen recorder with pyth...

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@neon lagoon

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sour pollen Jan 31, 2025, 9:28 PM

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neon lagoon hello! i am trying to make a super generic lightweight screen recorder with pyth...

Did you not try the ffmpeg command the other guy sent in the discussion channel?

neon lagoon Jan 31, 2025, 9:29 PM

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sour pollen Did you not try the ffmpeg command the other guy sent in the discussion channel?

i want to do it programatically, not on the command line as i said

sour pollen Jan 31, 2025, 9:30 PM

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ok, then

import os
os.system('ffmpeg -framerate 15 -pattern_type glob "<images_folder>/*" -c:v <video codec> out.mp4')

neon lagoon Jan 31, 2025, 9:30 PM

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ok -_-

sour pollen Jan 31, 2025, 9:31 PM

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Other than that, i think OpenCV videowriter has a FPS argument

stuck kiln Jan 31, 2025, 9:31 PM

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neon lagoon i want to do it programatically, not on the command line as i said

https://pypi.org/project/python-ffmpeg/

neon lagoon Jan 31, 2025, 9:31 PM

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what is the video codec

neon lagoon Jan 31, 2025, 9:31 PM

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sour pollen Other than that, i think OpenCV videowriter has a FPS argument

it does and i filled it in

sour pollen Jan 31, 2025, 9:31 PM

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neon lagoon it does and i filled it in

Ok. What happened?

neon lagoon Jan 31, 2025, 9:32 PM

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sour pollen Ok. What happened?

the video is faster than its supposed to be

sour pollen Jan 31, 2025, 9:32 PM

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did you double check in vlc that it shows a different frame rate?

neon lagoon Jan 31, 2025, 9:32 PM

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i dont have or know vlc

sour pollen Jan 31, 2025, 9:33 PM

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neon lagoon i dont have or know vlc

Ok then right click the video file and go to the details tab:

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What does that say for yours?

neon lagoon Jan 31, 2025, 9:34 PM

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sour pollen Ok then right click the video file and go to the details tab:

i dont actually have a file rn

sour pollen Jan 31, 2025, 9:34 PM

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🤦‍♂️

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then don't tell me "you tried opencv but the video was too fast"

neon lagoon Jan 31, 2025, 9:34 PM

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i tried it

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and i deleted it

sour pollen Jan 31, 2025, 9:34 PM

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try again

neon lagoon Jan 31, 2025, 9:34 PM

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and im gonna get it fropm the trahs

sour pollen Jan 31, 2025, 9:35 PM

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i mean how long did it take to make?

neon lagoon Jan 31, 2025, 9:36 PM

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no time

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anyway i have trhe file

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it says 15.00000000000000 FPS

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sour pollen Jan 31, 2025, 9:37 PM

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🤷‍♂️ looks like it worked then

neon lagoon Jan 31, 2025, 9:37 PM

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it still fast

sour pollen Jan 31, 2025, 9:37 PM

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Says it's only 2 seconds. Did it use all the files?

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that would be 30 frames yeah?

neon lagoon Jan 31, 2025, 9:37 PM

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definitely

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it was like

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more than that

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i have 2700+ frames rn saved that we can test

fast barn Jan 31, 2025, 9:38 PM

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2700/15 = 180

sour pollen Jan 31, 2025, 9:38 PM

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Maybe try the ffmpeg command just to see if it works

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see if it produces what you want

neon lagoon Jan 31, 2025, 9:39 PM

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import os
os.system(f"ffmpeg -framerate {FPS} -pattern_type glob {path} -c:v mp4v out.mp4")

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AVFormatContext @ 0000019ad749b240] Unable to choose an output format for 'C:\Users\Uzivatel\Videos\diepio_recording_001'; use a standard extension for the filename or specify the format manually.
[out#0 @ 0000019ad749af00] Error initializing the muxer for C:\Users\Uzivatel\Videos\diepio_recording_001: Invalid argument
Error opening output file C:\Users\Uzivatel\Videos\diepio_recording_001.
Error opening output files: Invalid argument

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lemem delete this rq

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ok i ran its kinda stuck

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OK OK

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it made a video

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it did it

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but its faster than its supposed to be

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big success

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the 2m video is 125mbs 💀 its because of the quality i think

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i hope i can degrade it after

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@sour pollen

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pls ;-;

sour pollen Jan 31, 2025, 9:48 PM

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neon lagoon pls ;-;

Did you have a question?

neon lagoon Jan 31, 2025, 9:48 PM

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sour pollen Did you have a question?

how do i not make it fast now

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and how do i degrade the quality

sour pollen Jan 31, 2025, 9:51 PM

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neon lagoon how do i not make it fast now

Maybe 15fps is not what you expect it to be? How long does your output video run?

neon lagoon Jan 31, 2025, 9:52 PM

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sour pollen Maybe 15fps is not what you expect it to be? How long does your output video ru...

i select 15
i input 15
properties say 15
plays at 30 fps speed ;-;

sour pollen Jan 31, 2025, 9:52 PM

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neon lagoon i select 15 i input 15 properties say 15 plays at 30 fps speed ;-;

how long does it play?

neon lagoon Jan 31, 2025, 9:53 PM

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the sample video i made plays for 2:24

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with 2,726 frames

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at 15fps

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(1900 x 1080 quality)

sour pollen Jan 31, 2025, 9:55 PM

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neon lagoon the sample video i made plays for 2:24

Can you try adding a -r 15 before the -c

neon lagoon Jan 31, 2025, 9:56 PM

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sour pollen Can you try adding a `-r 15` before the `-c`

im not doing that

sour pollen Jan 31, 2025, 9:56 PM

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You can also try -vcodec libx264 -vf format=yuv420p before out.mp4 to drop down to 420p

neon lagoon Jan 31, 2025, 9:56 PM

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im still using cv2

sour pollen Jan 31, 2025, 9:57 PM

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neon lagoon im still using cv2

You don't want to try?

neon lagoon Jan 31, 2025, 9:57 PM

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ok i will

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guide me but i have to go to sleep in 3mins because tomorrow im having my PET exam

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drop all the explanations here ill look at them tomorrow

sour pollen Jan 31, 2025, 9:58 PM

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sigh

neon lagoon Jan 31, 2025, 9:58 PM

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ITS NOT MY PROBLEM I DONT HAVE TIME

sour pollen Jan 31, 2025, 9:59 PM

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import os
os.system(f"ffmpeg -framerate {FPS} -pattern_type glob {path} -r 15 -c:v mp4v -vcodec libx264 -vf format=yuv420p out.mp4")

sour pollen Jan 31, 2025, 9:59 PM

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neon lagoon ITS NOT MY PROBLEM I DONT HAVE TIME

It 100% is your problem

mighty fog Jan 31, 2025, 9:59 PM

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just.come back tomorrow?

neon lagoon Jan 31, 2025, 9:59 PM

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sour pollen It 100% is your problem

:(

neon lagoon Jan 31, 2025, 9:59 PM

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sour pollen ```py import os os.system(f"ffmpeg -framerate {FPS} -pattern_type glob {path} -r...

.bm

fast barn Jan 31, 2025, 10:04 PM

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sour pollen You can also try `-vcodec libx264 -vf format=yuv420p` before `out.mp4` to drop d...

yuv420p is the pixel format, how colors are represented, not resolution

stuck kiln Jan 31, 2025, 10:33 PM

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neon lagoon ok i will

is that geomy das on your profile

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geomy das

sour pollen Jan 31, 2025, 10:50 PM

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fast barn yuv420p is the pixel format, how colors are represented, not resolution

Ah my bad

white charmBOT Jan 31, 2025, 11:50 PM

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#🔒 Convert images (frames) to a video with ffmpeg or cv2