How to fix "Cannot find a valid font for the family Sans' while adding text on image using react-native-ffmpeg - react-native

Question

I am trying to add text on image using the code below
RNFFmpeg
.execute(`-y -i ${input} -vf "drawtext=text='Hello World':fontcolor=white:fontsize=75:x=0:y=0" ${output}`);
I am not using any custom font but still get this error.
Error:
[Parsed_drawtext_0 # 0x7f87a1ce40] Cannot find a valid font for the family Sans
index.js:115 [AVFilterGraph # 0x7f6765e760] Error initializing filter 'drawtext'
index.js:115 [AVFilterGraph # 0x7f6765e760] with args 'text=Hello World:fontcolor=white:fontsize=75:x=0:y=0'
index.js:115 [AVFilterGraph # 0x7f6765e760]
index.js:115 Error reinitializing filters!
index.js:115 Failed to inject frame into filter network: No such file or directory
index.js:115 Error while processing the decoded data for stream #0:0
Note:
I also tried using a custom font but not able to do it.
When I use RNFFmpegConfig.setFontDirectory('../../assets/fonts') function and with it the following code to add text on image
RNFFmpeg
.execute(`-y -i ${input} -vf "drawtext=text='Hello World':fontfile='../../assets/fonts/MyFont.ttf':fontcolor=white:fontsize=75:x=0:y=0" ${output}`);
It gives me the same error.
How can I fix this issue.

Answer 1

according to this
https://github.com/tanersener/ffmpeg-kit/wiki/Tips
you should registering the fonts under a directory using the FFmpegKitConfig.setFontDirectory methods or by specifying your own fontconfig configuration using FFmpegKitConfig.setFontconfigConfigurationPath
System fonts on Android are stored under the /system/fonts folder
and on iOS are stored under the /System/Library/Fonts