6 Replies Latest reply on Apr 22, 2011 6:54 AM by the_wine_snob

    .avi files and codecs

    L3pton Level 1

      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?



        • 1. Re: .avi files and codecs
          the_wine_snob Level 9

          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.



          1 person found this helpful
          • 2. Re: .avi files and codecs
            L3pton Level 1

            Thanks Bill for the reply. The frame size for my file is 1280 x 720 and the PAR is 1.000 (1:1), how do I access the project preset?. It says the CODECs are installed, but how do I process the file with the two you listed?



            • 3. Re: .avi files and codecs
              the_wine_snob Level 9

              For the Project Preset, you can go to the Toolbar at the top of the main editing screen and look at Edit>Project Properties, unless that has been moved in PrE 9.


              When CODEC's are properly installed in the system, and they are ones that PrE can use, the program will use the one with the highest priority, for Import. This is usually the last one installed. For Export/Share (MJPEG is seldom used there), one has a drop-down list, that will be accessed in Advanced and Compresson, or similar syntax, but the exact location can differ by format, and also all CODEC's are not available, again depending on format chosen.


              For MJPEG, one would not need more than one of those two. If one has an MJPEG CODEC, installed from the camera's utility disc (could be separate install, with the driver or with the included editing software), they should not need to install any others, as the camera mfgr. has usually optimized the contained one, with the CODEC used by the cameara.


              As you have the MJPEG CODEC installed, I would look first at the match between the Project Preset and the Source Files. If there is still a mis-match, then hitting Enter to Render the Timeline, or parts of it, should get a good, smooth playback - the red line turns green.


              Check for a mis-match first, report, and then we can move on a few steps.


              Good luck,




              PS - I am a big fan of ONLY installing the exact CODEC's needed, when needed, and NOT just installing every CODEC, that one can find. Keeping one's computer as clean, as is possible, is paramount.


              Message was edited by: Bill Hunt - Added "Edit" to Project Properties.

              • 4. Re: .avi files and codecs
                John T Smith Adobe Community Professional & MVP

                >how do I access the project preset?


                Download the PDF for your version to have easy searching


                P-Elements 9 http://help.adobe.com/en_US/premiereelements/using/index.html

                1 person found this helpful
                • 5. Re: .avi files and codecs
                  L3pton Level 1

                  Thanks for the help. It was the mismatch between the file and project preset causing the problem, NTSC was selected when it should have been PAL.

                  • 6. Re: .avi files and codecs
                    the_wine_snob Level 9

                    Glad that you found where the mis-match was, and for reporting the details.


                    Good luck, and happy editing,