CODEC's and info on all, could fill a very large book. Also, much is changing at a very rapid pace.
Now, to help you specifically, PE (like Adobe's other NLE program, PrPro) is designed around a DV-AVI Type II workflow. This means that it is most comfortable with these, using the DV CODEC. Also, it works best with Audio in the PCM/WAV format, with a 48KHz sample rate, and 16-bit bit-depth. This is obviously for SD material. Since PE7, fairly direct support for pure AVCHD HD material was added. Realize that even knowing a particular CODEC might not tell the full story. There are variations on many, with new variations coming all of the time.
Back to your specific use and need: you will ALWAYS be better off, if you convert your material to DV-AVI Type II w/ PCM/WAV 48KHz 16-bit Audio, BEFORE you Import. PE will attempt to convert other formats/CODEC's to that, if it can. Should one have the proper CODEC's (can be totally different for the Video content and the Audio content if the file is multiplexed, i.e. containing both an Audio and a Video stream in a single file.
In the attempt to make this conversion internally, PE can get some things wrong. All too often, OOS (Out Of Sync) issues develop. Sometimes, PE will only be able to handle the Video portion, or the Audio portion of the file. You'll see alot of posts along the lines of, "hey, my Audio plays great, but my Video is missing... " PE also uses a large bit of the available resources from the system doing the conversion internally. This slows everything down, and often crashes the program. At the best, the editing process will be slowed.
In the case of the FRAPs capture program, I do not know which formats it can Export to, once the capture is done. You should have a few choices, but you'll need to tell us what they are. It could also be that it will use most properly installed CODEC's on your system. This would mean that your list of possible Export CODEC's is limited to what you have now. It might be, that you can install others, and have FRAPs use those.
Personally, I'd choose an Export CODEC that was either uncompressed, or only slightly compressed, and then convert this to DV-AVI Type II with PCM/WAV 48KHz 16-bit Audio. Import that converted file into PE and edit easily.
Now, if you have HD source material, then all bets are off. You will need to get input from folk, who edit HD material to get recs. on which formats/CODECs PE will love. For camera-generated material, the AVCHD format is good, though requires a robust computer to edit easily, or smoothly.
I second what Hunt says.
While technically there is almost no such thing as a lossless codec, the program is built to run AVIs using the DV codec (DV-AVIs).
They perform most efficiently in the program and, unless effects are added to them, they can pass through an editing project virtually unchanged.
DV-AVIs, by the way, are the format produced with miniDV footage is captured over FireWire. The video in a miniDV camcorder is, in fact, already compressed with the DV codec, so video captured from miniDV camcorders comes into your computer virtually unchanged.
This is why miniDVs remain the standard camcorder format for PC and Mac-based editors.
The first two lossless CODEC's, that come immediately to my mind, are Lagarith and HuffYUV. These are useful, when going to/from AfterEffects as "intermediate" transfer CODEC's. My PE4 sees these, as they are installed on my system. I have never used either with PE, so do not know how well, or poorly, they might work. If one really needs a full "lossless" CODEC, they might try these. They should be warned, however that YMMV (your mileage might vary). Obviously AVI (uncompressed) is lossless, but man is the resulting file ever large! If one is using these, many TB's of storage will definitely be required.
But the bigger issue, Hunt, is that a lossless codec is probably not the best codec to use with Premiere Elements.
The program itself uses a DV-AVI workflow -- so, even if you load another codec into it, the program itself assimilates it as a DV-AVI in order to work with it. Using another codec (or even an uncompressed file) just gives the program a lot more work to do. It ultimately does not produce a higher quality file. The program still converts it to a DV-AVI before it outputs anything else.
Trust me. You want to use a DV-AVI as your source file whenever possible.
Oh, I do agree. Because both PE and PrPro are fashioned around DV-AVI Type II, that is always my first choice, regardless of the slight lossy nature of the DV CODEC. That is what I convert all other formats to, and only use other CODEC's for going to/from AfterEffects.
As you point out, there is a big difference in an NLE Exporting to a CODEC and then Importing the same CODEC. There is even a bigger difference with the NLE basically converting that CODEC to DV-AVI Type II and then working with it.
I just wanted to mention that there are some lossless CODEC's. Their use comes in handy with some programs, but certainly not all.
Many thanks for your answers.
I think now I get the point. Since FRAPS can't export another avi, I have to convert it to a DV-AVI type after recording (which does not belong to this question ). There will still be some trial and error to get it working, but this showed me the way to go.
There will always be that "trial and error" aspect. With the number of programs, cameras, etc., that use various CODEC's and new ones coming out monthly (or variations on existing ones), a user has to do their homework to stay current. As I stated up-thread, camera mfgr's. are always looking to squeeze a touch more quality into a smaller package, so their coders are always looking to tweak what's already out there, or create a new CODEC.
Some of these play-nice with existing NLE's, but many do not. For SD work, the goal is to get to DV-AVI Type II, in the fewest possible steps. With HD material, the water is very muddy right now. It appears that AVCHD is in the lead, though working with that format is very taxing on one's system, and the need to upgrade to the "latest and greatest" is very high, indeed. Even with AVCHD, there is a "lite" version, that is causing some a bit of grief.
In the pro ranks, the Red camera and its files are right around the corner for Adobe. There is much speculation that Red and Adobe will have it all working with the CS4 4.1 release - due any day now. A new CODEC for Adobe is on the horizon. Some of the older "players" like CineForm have yet to update their output to match what is currently available. There material works well in CS3, but has yet to be updated to CS4, or had not been, last time I checked.
One reason that the Sony Vegas products work so well with some of the Sony CODEC's is that the development labs are right next door and projects are usually a dual effort. Companies, like Adobe, have to wait until the format/CODEC has been released, and then re-code for it. There is a definite lag with this method. Some users and potential users bash Adobe (and others), because Vegas can do it, so why can't Adobe? If they got the code and the specs, before they were released, they could, to a degree. Vegas gets to time their releases to coincide with the release of a new format/CODEC on Sony cameras. Adobe has no such luxury.
A good book on all things DVD, DVD Demystified, by Taylor, Johnson & Crawford, Mc Graw Hill, has a lot of great info on CODEC's, but because it's printed material, will never be at the cutting edge. Even though it just covers the CODEC's used in the production of DVD's and BD, it will always be behind the development curve with regards to the latest developments. Even on-line material lags behind. Catching pod-casts from all of the "players" is about as good as we can get, and then one often has to "read between the lines."
Yes, the world of CODEC's is a wonderous and mysterious realm. In video (and still) production, we need them daily, and will always be behind the curve, but we usually do not need to know how to write them. With tools like G-Spot, Google and fora like this one, we can pretty much stay as current, as we need to be.
Last comment: I am a firm believer in only having the CODEC's that I need on my system. There are no bonus points for having the most CODEC's on one's machine. I also look for the paid version from the developer of any that I do need, and will spend $, rather than go for a possibly hacked, or reverse-engineered free version. This does not mean that free CODEC's are bad - only that I will pay to get as close to the source, as is possible. I want something that always works with my system and something that will do the best job possible.