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I find the recent two articles on DivX in comparison to MPEG2 relatively misleading. The statement that a 9-to-1 compression is even remotely likely is about as convincing that VHS copy of a DVD renders comparable results. I have spent considerable time both in the MPEG2 (SVCD) and DivX arena and found that for either to achieve high-quality results a datarate of about 2000mbits/sec is required. While DivX in this case does not require a reduction in resolution one should not overlook the fact that an excellently compressed 480x480 SVCD image beats a 720x480 image that exhibits macroblock noise, even at marginal levels. Considering the fact that DivX allows for cropping of the movie area the results are a tad disappointing. One should also note that DivX does not allow for VBR encoding and requires considerable computing time even for VKI (insertion at keyframes at scene changes through automatic detection). The DivX 3.2 codec simply doesn't cut it here and a two pass process is required, very time-consuming when using bicubic resizing.
The bottom line that I have found is that there are excellent commercial and free tools (TMPGEnc and Cinemacraft encoder) that allow for several pass VBR processing that in many cases let the final SVCD style image excel. The lack of standalone player support (DivX is a hack and will never gain commercial support) and the fact that it requires data CDs vs. SVCD CDs with reduced ECC, allowing more data to fit on a single CD, finally give SVCD (MPEG2) the advantage in the race for movie encoding.
Sorry, both articles in this area by Andreas Voelkel are a bit overenthusiastic for the MPEG4 format. The articles, in their comparison of quality also lack the insight that movie quality should not solely be judged upon a frame's appearance when rendered as a still but the whole impression of playback is to be considered. Many other areas were also insufficiently or plain incorrectly covered. Andreas could have done a better job but then again, this is a wide playing field and to come up with an interesting and concise article must have been hard.
Let's see what MPEG7 has to offer when it is discovered by the ripping community. Maybe then a real alternative to MPEG2 will emerge.
The bottom line that I have found is that there are excellent commercial and free tools (TMPGEnc and Cinemacraft encoder) that allow for several pass VBR processing that in many cases let the final SVCD style image excel. The lack of standalone player support (DivX is a hack and will never gain commercial support) and the fact that it requires data CDs vs. SVCD CDs with reduced ECC, allowing more data to fit on a single CD, finally give SVCD (MPEG2) the advantage in the race for movie encoding.
Sorry, both articles in this area by Andreas Voelkel are a bit overenthusiastic for the MPEG4 format. The articles, in their comparison of quality also lack the insight that movie quality should not solely be judged upon a frame's appearance when rendered as a still but the whole impression of playback is to be considered. Many other areas were also insufficiently or plain incorrectly covered. Andreas could have done a better job but then again, this is a wide playing field and to come up with an interesting and concise article must have been hard.
Let's see what MPEG7 has to offer when it is discovered by the ripping community. Maybe then a real alternative to MPEG2 will emerge.