Gst.Buffer.prototype.replace_memory_range

function replace_memory_range(idx:Number, length:Number, mem:Gst.Memory):void {
    // Gjs wrapper for gst_buffer_replace_memory_range()
}

Replaces length memory blocks in buffer starting at idx with mem.

If length is -1, all memory starting from idx will be removed and replaced with mem.

buffer should be writable.