我尝试使用此命令合并两个视频：
mkvmerge -o output.mkv intro.mkv +sony-headphone-Hs.mkv
但失败了：
mkvmerge v21.0.0 ('Tardigrades Will Inherit The Earth') 64-bit
'intro.mkv': Using the demultiplexer for the format 'Matroska'.
'sony-headphone-Hs.mkv': Using the demultiplexer for the format 'Matroska'.
'intro.mkv' track 0: Using the output module for the format 'AVC/h.264'.
'intro.mkv' track 1: Using the output module for the format 'Opus'.
'sony-headphone-Hs.mkv' track 0: Using the output module for the format 'AVC/h.264'.
'sony-headphone-Hs.mkv' track 1: Using the output module for the format 'AAC'.
No append mapping was given for the file no. 1 ('sony-headphone-Hs.mkv'). A default mapping of 1:0:0:0,1:1:0:1 will be used instead. Please keep that in mind if mkvmerge aborts with an error message regarding invalid '--append-to' options.
Warning: The track number 0 from the file 'sony-headphone-Hs.mkv' can probably not be appended correctly to the track number 0 from the file 'intro.mkv': The codec's private data does not match (lengths: 43 and 43). Please make sure that the resulting file plays correctly the whole time. The author of this program will probably not give support for playback issues with the resulting file.
Error: The track number 1 from the file 'sony-headphone-Hs.mkv' cannot be appended to the track number 1 from the file 'intro.mkv'. The formats do not match.