FFmpeg:如何转换背景边模糊的垂直视频

Question

我执行以下命令来模糊视频背景，但出现错误。

String[] complexCommand = {"-i", "" + yourRealPath, "-lavfi", "[0:v]scale=ih*16/9:-1",
    "boxblur=luma_radius=min(640,356)/20", ":luma_power=1:chroma_radius=min(cw,ch)/20",
    ":chroma_power=1[bg]", ";[bg][0:v]", "overlay=(W-w)/2:(H-h)/2",
    "crop=h=iw*9/16", "-vb", "800K", filePath};

错误：

无法为'boxblur=luma_radius=min（640,356）/20' 找到合适的输出格式 boxblur=luma_radius=min（640,356）/20：参数无效

Answer 1

这个片段对我来说效果很好：

"-i", input,
"-strict", "-2",
"-filter_complex", "[0:v]scale=ih*16/9:-1,boxblur=luma_radius=min(h\,w)/20:luma_power=1:chroma_radius=min(cw\,ch)/20:chroma_power=1[bg];[bg][0:v]overlay=(W-w)/2:(H-h)/2,crop=h=iw*9/16",
"-c:v", "libx264",
"-pix_fmt", "yuv420p",
 output