.avi files and codecs

Question

Hi I posted a question yesterday about .avi and there were some helpful responses. I installed GSpot and it tells me that the CODEC for the video file is MJPG/Motion JPEG, on an Olympus Pen EPL1 digital camera, and there is no CODEC required on the audio file. It then says that the MJPG CODEC is installed on my computer, so why when I import the file into Premiere Elements 9, it plays back in very poor quality?
Regards

Answer 1

Poor playback, when the proper CODEC is installed on one's system is often due to a mis-match between the Source Files, and the Project's Preset. The biggest killer of Quality, is when the Frame Size of the Project does not match the Frame Size of the Source Files, and Scaling is done, with Scale to Default Frame Size checked.
The next most common cause of a lack in quality is the specific CODEC itself. For MJPEG, there are two highly popular CODEC's, Morgan and MainConcept. While there are others, those two are highly recommended by many users. Many cameras, that shoot in MJPEG will also ship with the mfgr's. version of the MJPEG CODEC. As that mfgr. might well have tweaked things a bit, if one does have a utility/driver disc, I would strongly recommend installing their version of MJPEG. This might be installed along wiith the driver for the camera, as part of an editing/organizing program, or maybe as a separate install. It will just depend on the camera, and might even vary, model to model. This ARTICLE will give more background, and also some potentially useful links.
Let's go back to the first paragraph. When you ran your Source Files through G-Spot, what were the Frame Size and PAR (Pixel Aspect Ratio) listed?
How do those figures match up with your Project Preset, chosen with New Project? A mis-match here can have a very negative effect on quality. If one has Scale to Default Frame Size checked, and the Source Footage is smaller, than the Project's Frame Size, the user will not see that the program has Scaled UP the Clip(s) to match. If Scale to Default Frame Size is unchecked, then the user would see black bars around all, or parts of the Frame, with the Clip displayed smaller in the Frame.
While PrE can Scale footage UP, or DOWN, its algorithms are not the best and quality will suffer. A little bit of Scaling might go unnoticed, but if one had, say SD 720 x 480 material, in an HD 1920 x 1080 Project, then quality would go down dramatically.
One thing to consider is that if there is a mis-match, there will be a red line over the Clip(s). This shows that for the best, smoothest playback, that footage needs to be Rendered. One would press Enter to Render that Timeline. The Render could be limited to just a segment of the Timeline by using the WAB (Work Area Bar). This produces proxy files, that will give the best possible playback. This ARTICLE will give more background on Rendering. While the Program Monitor in the program, on a high-rez computer monitor is not the best viewing situation for SD material (an NTSC, or PAL, calibrated CRT monitor is the best, but those are very expensive, and the NLE program needs to support them), one can get fairly close by adjusting the Magnification (Rt-click on the Program Monitor) to 100% from Fit. To see the entire Frame, it might be necessary to adjust the Program Monitor's Panel.
As you can see, there are several things that can affect quality. If you will give us info on your Source Footage, your Project's Preset and also which version of the MJPEG CODEC, someone will be able to direct you.
Good luck, and thanks for the info.
Hunt