MPEG-4 (MP4) is a container video format that can store multimedia data, usually audio and video. To accomplish this, download the Combined Community Codec Pack (CCCP) from a trusted site, such as Ninite. Therefore, another option for opening an MKV file is to download the appropriate codecs that are compatible with the selected media player. This is important because MKV is not an industry standard, which means that other media players might not support it.Īdditionally, MKV does not use codecs to compress file size, which means the file can be quite large. This media player is compatible with all operating systems and platforms. The best way to open an MKV file is to use VLC media player. The name derives from “ Matryoshka” dolls, which is a famous type of Russian handicraft that consists of a set of wooden dolls of decreasing size nested one inside another. Since it is open source, a user can customize it with open-source software. In this case even if your original file has 2 video tracks, 4 audios, mpeg2 video codec, or whatever, the output will always have the correct video and audio format and it will discard any other unwanted streams.Matroska (MKV) is a free, open-source, container standard that can hold an unlimited amount of audiovisual and multimedia files in a single file format.

The best way to handle this would be to map the streams you need from the original file -map 0:v:0 (first video stream) -map 0:a:0 (first audio stream) and then use the codec selection to transcode into -c:v libx264 -c:a aac You were lucky that previously the video format on the original container was compatible with the mp4 container, but as you noticed it did not work this time. The root cause of the problem is the -c copy command, what it does is that it actually copy everything inside the original file and mux it to a new container, in your case mp4 and it also is copying all the other stuff (subtitles etc).

Ffmpeg mkv to mp4 aac