Merging multiple video files without modification

I know that this is possible

Just not with Adobe software.

My original source is a 1920x180 file which is 40.5MB. Choosing the High Quality HD 1080 preset I get an out put size of 391MB with a bitrate of 20Mbps.

Now look at the Twitter HD preset which gives an export size of 41MB but at 2.05 Mbps. Even at this bitrate it is adequate for small screen viewing.

My advice is to going into a preset you are comfortable with and adjusting the bitrate to give you the size and quality you are looking for. This might take you a few attempts before you achieve your goal. Once you do save it as your own preset for future use.

Let me know how it goes

Mo

From what I am reading all you want to do is add 3 files on the timeline and export the as one.

Easy enough so far. The trick comes in when you want to be specific on output size and quality.

As an example:

3 x 30MB (720p 25fps) won't give you one 30MB file out unless you drop the preset to say a Twitter HD preset, which I must say is rather excellent at keeping file sizes really low but with very acceptable quality,

I suggest using this preset and then playing with the Bitrate slider which is set at 2.05 by default.

You're describing a process that Adobe calls "Smart Rendering".

Unfortunately, this isn't supported with MP4.

You can find more information about Smart Rendering here:

Smart rendering in Premiere Pro

The process is also referred to as appending video.  The 32-bit version of QuickTime supports this with QuickTime Player 7 or older as long as you save to a .mov file. 

As far as I'm aware, the .MP4 specification does not support this (there's the whole demuxing/muxing thing).

-Warren

If you want a straight concatenation, you need one of the 'muxing' or whatever they're called apps.

Premiere Pro is built simply as an NLE, so ... you cut clips together on a sequence, then you export that to new media. Different process.

Neil