Manim: program ok,but the video just black screen

[donglx2004]

I run the program ok,but the video just black screen ,how can I fix it ?

[pu17]

my program also have the same problem,but I don’t know how to fix it

[MedNait]

Got the same problem too, black screen with no sound, even though there are no apparent errors! I tried on both windows and ubuntu and got the same result.

[fusir]

Same.

file gives me ISO Media, MP4 Base Media v1 [IS0 14496-12:2003]

For another working mp4 I get ISO Media, MP4 Base Media v1 [IS0 14496-12:2003]

The same so investigating if the file is corrupted at least the header isn't.

[fusir]

See this issue: https://github.com/3b1b/manim/issues/119

Apparently using docker creates this problem. I was using docker. Unfortunately using arch its default python3-ness is a bitch with dependencies that haven't learned that print( is superior to print.

[fusir]

Sorry to dominate this thread but I've solved the issue.

The issue is that particular animation is black on black.
See: https://ipfs.io/ipfs/QmYc9mCqPRtmw9GcSQckaB1RGNgSoqGJLWdEo4VMHbzg42/vidw8.mp4

I saved the pngs and used convert to change the alpha channel to white and then passed it into ffmpeg.

For reference:

for i in {1..180}
do
 convert frame$i.png -background white -alpha remove wframe$i.png
done

for i in {0..180}
do 
 cat wframe$i.png; 
done | ffmpeg -i - -c:a acc -c:v libx264 -crf 28 -tune animation -preset veryslow -pix_fmt yuv420p vidw.mp4

[burlito]

Hi,

Actually, I hit same issue, and with little bisecting It seems to be problem in aggdraw library, commit 242f55 https://github.com/pytroll/aggdraw/commit/183299329e8bbfcc5bbc280da492cc0a2c242f55

It seems that they are already aware about issue, https://github.com/pytroll/aggdraw/issues/20 ,
In meanwhile workaround is install aggdraw without commit 2c242f55 (lowe than 1.3 version)

[eulertour]

Closing, as this issue no longer seems to be present.