Joining files

[ForumID]

Sorry if the questions are quite dumb. I am new to media stuffs but I have large amount of dvd to rip,
I afraid heading to the wrong direction and I have to do it all over again in the future. I did some quality research on mkv, mp4 and avi.
It looks like both of them are containers but I am not sure about mp4. They are readable if I do a /copy merge on mp4, vob and mpg, but not mkv.

When we join 2 mp4 files, should we use the software like mkvtoolnix to join, or copy /b file.mp4+file.mp4 newfile.mp4 at dos? Are there any downside
if we use copy on mp4? or is that software like mkvtoolnix only helps when they have different setting like bitrate, audio etc.

Another question is, extracting the mpg from vob directly has the best quality?
I assume if we don't care the file size, I should always extract to mpg if possible? If there are several chapters, I extract them to few mpg and join them by /copy.
Am I heading to the right path? Should I only compress to mkv if the vob is encrypted?

Any help is appreciated.

[Cornucopia]

1. Mp4 is a container also, though many don't understand that and assume it means the (usually) AVC/h264 that resides in that container.

2. Appending ANY type of media via simple binary copy methods is a BAD IDEA. If you don't fully understand this, look up some of my past posts on this where I explain in depth what's going on behind the scenes. Some container formats and their readers/players may be more robust and withstand the discontinuities better than others, but for media files to consistently work properly, one should ALWAYS use AT LEAST a concatenator that understands the muxing & header/packet properties of the format(s) in question.

3. Encrypted files are of no use to you or anyone else (unless you are doing the encrypting, for a reason). Always decrypt first, while ripping (and here I use the true term for ripping which means just extracting off of the optical disc onto another medium).

4. What you should end up with will be determined by what your needs are. One person may want all their material left as-is and ripped to full disc ISOs. The next person may want plain MPG2 Program Streams or VOBs for DVD and MPEG2 Transport Streams (M2TS) for Bluray. The next person might want all material kept with the same original codecs but placed inside MKV container (as MakeMkv does), while another person may be using these only for final mobile playback and will want to reconvert everything to AVC-in-MP4. All these methods can be valid, depending on the circumstances.

5. Sounds like you might need to do a little MORE research.

Scott