Just to give you a tip-of-the-iceberg oversimplified answer, a lot depends on what the formats are, and also why you're converting them....

a) are the native camera "formats" digital or analogue, and are they on tape, or are they in files?

b) are they hi-def or standard-def?

c) are you converting them for playback only, or for editing and/or eventual conversion to another format (eg, editing in a NLE (non-linear editor) and perhaps for eventual conversion to a playable DVD.

d) are you planning to archive this material? For possible later re-editing, or in finished form? How do you plan on storing it?

e) professional or personal use?

The answers to (c) and (d) can get particularly complex, as when you ask any editor what "format" he/she would like, they will always tell you that they'd like to have it in the native format or "codec" of the NLE they're using. This turns out to be an ever changing target, and no one I know has come up with a universal answer. For more on "codecs", see links at the bottom of this post.

There are lots of issues in going "cross platform", some simple once you're aware of what they are, some not. Some Apple formats, eg, are proprietary, and many professionals are not confident that Apple will maintain support for them. There are also Apple-PC issues, and there can be aspect-ratio issues.

I will take the liberty of mentioning what's generally considered to be at the top of the line encoding/transcoding software for most professional uses, and that's Adobe Media Encoder, which comes bundled with Adobe Premiere Pro, Adobe After Effects, and Adobe Prelude software. I don't think it's available standalone. It's not cheap.

Recommended hardware for Adobe Premiere Pro is:
Intel Core2 Duo, 64-bit, 8GB of RAM, preferably RAID drives.

Adobe Premiere Elements is scaled down from the Pro version, and is roughly $100. System requirements are less. The Elements Encoder also less versatile with some file formats. I imagine it's adequate for most consumer cameras, but I don't know. I'd guess from your questions that the Elements Encoder might be what you want, if it supports the formats you need. There are also several utilities that I'll discuss with the mod about whether I can post.

Regarding hardware... for many personal uses, some performance glitches might not matter. A friend who outputs his Nikon DSLR video to FCPX routinely shows "dropped-frame" messages, but the video looks generally OK and the dropped frames don't seem to matter, though they might affect sound sync.

Analogue tape will require a hardware I/O device as well as software to encode.

Also, there are lots of other "encoding" and "transcoding" video conversion utilities, some free, that posters are liable to drop names to, and for the time being I think it's probably best not to discuss those... until we clear with the moderator here. Cheap codecs can be a problem, and some utilities include codecs that can conflict with other codecs needed for editing. Playback only and editing codecs may not play well together, but I'm not precisely sure of that. Generally, the free utilities convert between playback formats, not between intra-program editing formats.

Re archiving...

Archiving digital files on hard drives is considered problematic. As I posted on this forum several years ago, it was a problem that hadn't been solved... and it still hasn't been solved. More on that later.

Some professionals are continuing to maintain digital clones of the "last stable digital tape format", as well as to hold onto original film, as a way of future proofing valuable material, but machines and people to run them become harder to come by, and climate-controlled storage is expensive.

I've been in the process for several years of coming up with archiving procedures. Am currently in crunch mode on this as my media vault recently shut down. I've gotten my most important digital tapes and backups separated, in relatively climate controlled conditions (ie, inside, not in a humid warehouse, and in separated buildings). Frequent cloning is recommended, and that can get onerous and expensive.

Scoping out a computer that will handle uncompressed standard def and moderately compressed hi-def has been an ongoing project for me... perhaps fortunately interrupted as my requirements have changed.

For more on codecs, here's the standard introductory article...

FAQ: CODEC's, a Primer
by Bill Hunt
Jul 31, 2012
[forums.adobe.com...]

The article refers also to these two Wikipedia articles...

Codec
[en.wikipedia.org...]

Video Codecs
[en.wikipedia.org...]

More later, but this should get you thinking about requirements, whether you want to pass videos down to great grand kids, etc.

Thanks, that was a comprehensive reply which got me thinking.

These are mostly home videos, currently transferred to DVD to play on a DVD player, and some from the camera phone.

The ideal scenario is to convert them to the current format in vogue. So, for example, I have an Android device, and a PC, and a Mac. I'm not overly concerned about archiving right now as the DVD is the current archive. Although, I know, that too will have a finite life. At least, for now, the files are relatively stable on DVD in digital format.

I want to make it easy to output the desired format for the OS and screen size.

I am not a professional, it's primarily for home use, however, I can see where production of effective video files would make distribution easier.

I wanted to try a video conversion program, and found a whole host of them packed with unwanted baggage. I'm happy to pay for the software, but it needs to be reasonably lightweight (not bloatware) as i have non-commercial requirements.

The ideal format for archiving is the most original source, it's all downhill from there. If these were from a DV camcorder you want the DV file, if it was DVD camcorder you want the DVD file before it went through any conversion. Whatever the file is on the camcorder is the file you want to archive.

If these were transfers from VHS DVD is not a very good choice. VHS is typically noisy and since they are home videos it's probably hand held so there is lot of movement. That noise and movement taxes the encoder resulting in lower quality video than if you had used something like DV which is very lightly compressed or Huffy which is uncompressed.

If you've already burned that bridge, DVD uses MPEG2. There is a tool called VOB2MPG that will eliminate all the DVD stuff and produce a single video file. If you only have these on DVD I'd strongly suggest using VOB2MPG to rip a copy and store on disk. Burned DVD's will fail, the when depends on a lot like the quality of the disc which varies widely. It might be 30 years from now or might be tomorrow but they will fail.

As far as the conversion to other formats go the single biggest mistake people make is not using the source for new conversions. For example:

DV >> 8000kbps MPEG2 = Good method
DV >> 4000kpbs MPEG2 = Good method

DV >> 8000kbps MPEG2 >> 4000kpbs MPEG2 = Very bad method

That intermediate conversion can have very dramatic effect on the quality.

Thanks thecoalman

That's all very helpful.

I admit, at the time of saving, I really didn't think of archiving. But now I am, it's a recovery from the many formats into something which will have some longevity.

The original is on various media, saved at differing times. The oldest are on VHS, which is degrading, so it's a rescue mission there. The newest is on DVD, in DVD format for playing on DVD players.

I tried a few video converters and was surprised at how different they were. Some were sluggish and some were fast, despite setting the same quality of conversion.

I have yet to find and settle upon a video converter for non-commercial use.

The next challenge is to what media to save the original and converted files. Hard drives, now relatively cheap might be the current best bet, with, of course, multiple copies on other hard drives.
Any other suggestions?

But now I am, it's a recovery from the many formats into something which will have some longevity.

I'd be concerned about the physical medium becsue that is huge limitation, as long as you have files on HDD in widely used formats like MPEG2 or DV I wouldn't be concerned about it much because you can always move them to the "latest and greatest" physical medium. There is always going to be need to be able to read those for decades to come simply because they are so widely used. I'd suggest .jpg files will be able to be read 100 years from now and so will those formats, you no longer have the limitations of the physical medium.

The oldest are on VHS, which is degrading, so it's a rescue mission there.

If you have a DV camcorder you can check to see if it has the passthrough feature, it might be called something else. You hook your VHS deck deck up to the camcorder and it will convert to DV. That can be sent over firewire to your computer as DV file and/or record to DV tape. I always recommend DV converters for this process becsue they are fairly easy to use and produce excellent results. It's about 14GB per hour but it's very editor friendly format and only lightly compressed.

I tried a few video converters and was surprised at how different they were. Some were sluggish and some were fast, despite setting the same quality of conversion.

Personally I'm not concerned about fast, I want quality and encoders are not all the same. Your standard pay for editors are using Mainconcept which is really good encoder.

My suggestion is Corel Video Studio, they bought out Ulead a few years back and Ulead had two pro products. There DVD authoring software was considered one of the best in the business. In any event Corel dumped the pro line and folded many the pro features into Video Studio. It's their flagship video editor so you're not getting a stripped down product.

Any other suggestions?

At this point in time I think HDD and backups on DVD/Bluray is the best alternative.

Glad I found this thread, answers a few questions for me, probably raises a few more too.

Another common mistake is changing the settings if your source is MPEG or any other format with an adjustable bitrates. This only applies if you're editing for archiving, check your editors settings. It's usually called "smart render" or something like that. When you use that the only thing that gets re-enecoded is where the edits are. You save a lot of time because it's really just a copy from the source and since there is no conversion there is no loss in quality. This doesn't apply to something like DV becsue there is no settings.

Don't ever scale video up either, let the player or hardware handle it.

Don't ever deinterlace either especially for archive material, again let the player or hardware handle it during playback.

The ideal format for archiving is the most original source, it's all downhill from there.

I should add that is not absolutely true, if for example you're capturing VHS using a DV converter using some very light filtering on the capture can do wonders. This will also greatly improve your output for compressed formats like MPEG2 because the encoder doesn't have to allocate as much bitrate to the noise.

Virtualdub is a great tool for processing video and has numerous filters. There is lot of tricks you can do with this like creating sequential images and then use your favorite image editor to batch process the frames with a noise filter. One thing to note if you're going to explore this is be sure to read up on how to unfold interlaced frames before processing. then refold them...