我在我的mac上下载并安装了ffmpeg，但是，我在使用它时遇到了问题。我试着用
ffmpeg -loop 1 -i rho1.png -c:v libx264 -t 15 -pix_fmt yuv420p -vf scale=320:240 out.mp4
然而，输出是
ld: warning: ignoring file video, file was built for unsupported file format ( 0x66 0x66 0x6D 0x70 0x65 0x67 0x20 0x2D 0x6C 0x6F 0x6F 0x70 0x20 0x31 0x20 0x2D ) which is not the architecture being linked (x86_64): video
Undefined symbols for architecture x86_64:
"_main", referenced from:
implicit entry/start for main executable
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
在png。中使用一张图片创建视频需要帮助。