Tips for encoding movies into HAP

Have a question about Hap Codec,

have some export from blender which use .mkv (800ko) per files
when encoding with hap codec, file size is 61mo

wish to use AVF batch converter but it does not support mkv files.
so I’m using : ffmpeg -i yourSourceFile.mov -c:v hap outputName.mov

Am I doing something wrong ?

best