Using Video Game Footage - Part 2eRipping
MPEG Files I have downloaded a lot of MPEG files, or have had to convert an older MPEG file I created and archived for a little more editing. Normally you should not decode an MPEG-1 file since VirtualDub is able to read it natively, though you may choose to use Flask to decode it since you have better control over the iDCT. I have tested this on MPEG-2 files pulled from a DVD, submitted to completion, and created by myself. It has worked every time, without flaws. MPEG was created originally to allow for video to be encoded onto a CD, mainly in response to Phillips creating a CD standard and linking it into their console system. I cannot remember what it was, the console, but it has since failed. (Mechaman: The console was the Phillips CD-i and the standard was Green Book, which among other things, is an offspring of the XA format.) The committee was tasked with the creation of a video standard that could be played back on CDs, but future compatibility was not a driving issue. MPEG-2 was originally designed for higher quality digital video and aimed to be backwards compatible with MPEG-1 as well as handle a broader range of resolutions. MPEG-3 was created to work with High Definition Television, but it was discovered that MPEG-2 could, due to its flexibility, handle any of the specifications that MPEG-3 was created to handle. MPEG-3 was then disbanded, and its profiles rolled into the MPEG-2 speciation. MPEG- 4 was created to handle the Internet. It was started before MPEG-3 was disbanded, so was given the “4” number. MPEG-4 was created to allow for a wider variety of video coding standards, including sprite based and interactive content. MPEG-4 is still being finalized, though many of its video coding standards have been finalized and incorporated into other technologies. MPEG-7 is currently in the initial stages of development, and is aimed at creating a way for media clips to be described so that search engines and libraries can catalog them more effectively. The number “7” was chosen arbitrarily, leaving MPEG-5 and MPEG-6 undefined. MPEG-1 FAQ - http://bmrc.berkeley.edu/frame/research/mpeg/faq/mpeg1.html MPEG-2 FAQ - http://bmrc.berkeley.edu/frame/research/mpeg/faq/mpeg2.html MPEG-4 FAQ - http://www.cselt.it/mpeg/faq/faq_mpeg-4.htm MPEG-7 FAQ - http://www.cselt.it/mpeg/faq/faq_mpeg-7.htm Getting an MPEG file to your computer is relatively trivial. If you are pulling from a DVD-ROM, you will have to use a program to remove the encryption on the disc, otherwise it is simply a file. Some computer games use MPEG-2, and I believe that the PlayStation 2 and the XBox both use MPEG-2 as their native video format. MPEG-2 files can also have many streams imbedded within the file. There is normally more than one audio stream, though it is rare to find multiple video streams. Also, if you have a series of VOB files, Flask is able to “stitch” them together logically, and consider them one long MPEG file. When you load an MPEG file into Flask, it will scan the file, and determine how many streams, and the settings of the streams within the file. When the control panel pops up, you are able to view the video and review all of the detected settings. You also can mark in and out points of the video that you would like to extract. By selecting the “Audio Player” button you can check the audio, make sure it is the proper channel, and apply settings to it. If you want you can adjust the volume and normalize the audio. Plus if the audio is a multi-channel stream, you can choose how it is downsampled, or if the file has multiple audio tracks, you can choose the one you want. In the “Configure” button, you get a lot of the choices that deal with the video quality. For some insane reason, the resolution is defaulted to a PAL VCD. I normally set it to the file's original settings, visible on the first control panel. The time base is almost always setup correctly the first time and you should only change it if you know what you are doing. If the MPEG is 24 or 23.97 frames per second, you should try choosing “Reconstruct progressive images”. This option will restore a film's progressive nature. Be very careful with the “Deinterlace video” option. If a file needs it, experiment with the settings; though be aware there will be a minor quality hit. I have learned how to edit and work with interlaced video, but the details of that should be reserved for a different article. The iDCT is subjective. I like to remove the “Auto Select” and choose “Reference iDCT”, since it has the highest possible quality, but is the slowest. The audio tab should normally be left alone as should the other tabs, since the defaults normally work. If something does not look right.... Experiment until you like the output. The documentation is easy to read. When you “Select Output >>” choose OpenDML AVI. When you “Configure Output Module”, choose
Huffyuv as your video CODEC and <
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