What tools do you recommend for MP4 muxing? What kind of subtitles? (images or text)
I havn't had much fun with MP4Box. It seems it cannot mux multiple streams at once.

Edit: Maybe I should try the Yamb GUI like this. MP4Box itself prints out pretty cryptic command line help.

Cheers!
SG

I'm using megui. It's not a beauty GUI-wise but it has a nice auto-update feature and the "tools" section does pretty much everything, except ripping from disc or sat, of course. The video/audio profiles are a great help, too!

But I have to admit that I never really tried MP4Box, so I can't tell you the differences.

EDIT: MP4Box is just a muxer? Well, megui is much more than that, it's more like a whole suite.

Use Yamb to mux MP4, it's a MP4Box frontend. I recommend text subtitles as they are part of the MP4 standard where as VobSub's are not, there a proprietary Nero extension. You'll need Haali and VSFilter to play them back, SubRip can generate the correct format.

Edit: you can also use TVTagger to tag your MP4 file with iTunes style tags.

I use MeGUI also. I believe that it uses MP4Box to mux MP4 - but it provides a nice easy GUI for the purpose.

The subtitles are a proper (text) MPEG4 stream I believe - I'm not knowledgeable enough to say any more than that. I created an SRT file using SubRip and MeGUI used that to add the subtitles. In fact, on checking, it's possible that MP4Box is using them directly (as I point the muxing dialogue to the SRT). VideoLan reports the file to have four streams, with Stream 3 being the subtitles with a codec type of "subt".

Using VideoLan the subtitles can be switched on and off with ease, and I can also easily switch between the two audio channels.

I have used kurtnoise's Yamb for muxing also. I think that also uses MP4Box. As Fandango says, MeGUI is much more than just a muxer - I mainly use it for the encoding.

I am pretty clueless when it comes to video creation, but MeGUI makes things pretty easy to mess about with.

Edit: I have Yamb here at work, and it accepts SRT also - so I guess it is inherent MP4Box functionality.

Edit 2: Out of interest I just remuxed the film without subtitles, resulting in a file 56KB smaller in size. I can only assume that the subtitles are stored in text format in the MP4.

Edit 3: I can't stop playing now. I've just loaded the muxed MP4 into Yamb 2.0.0.7 and it describes the subtitle stream as "Timed - Timed text (3GPP)". IIRC Media Player Classic cannot render the subtitles.

Yamb can accept SRT files as input, but it will convert them to 3GPP Timed Text as specified in MPEG-4 Part 17. TTXT files are a lot more powerful than SRT files. Media Player Classic can render it as long as you use the Haalie Media Splitter and VSFilter. I believe VideoLAN can also play back subtitles of this nature. The best way to create TTXT files for MP4 is to use SubRip to rip straight to that format and then manually edit the file to specify position and font details.