Test 1: The Matrix
As usual I reviewed chapters 28-30, that's frames 140155 - 153948 from a total of 196155.
This is a chapter with very little action. On the other hand we have many close-ups and hard to encode background like uniformly colored walls that have a lot of film grain on them.
It is now possible to switch between the screenshots for a certain scene using the links below the image. The comment concerning the screenshot that is currently shown is displayed below the screenshot. By default, the source image from the DVD is shown. Many thanks to Zolaerla for the image switching and zooming script.
Then my usual disclaimer: Screenshots are not necessarily representative of the video quality. It might be that a screenshot of codec A just happens to fall onto an I-frame which is the least compressed (and thus looks pretty good), whereas quality quickly degrades after the frame shown in the screenshot. And a codec B might have a heavily compressed B-frame at the same position, so comparing the two would be inherently unfair. Bottom line: Take screenshots with a grain of salt, make sure you read all my comments and perform your own tests when in doubt. Every human being perceives visual quality differently and you might come to completely different conclusions watching the same clips as I did.
After having multiple looks at the first part of the interrogation I decided not to include any images of it. While you can still spot some differences on the walls, all codecs do a pretty good job which would make it extremely hard if not impossible to spot differences in a still picture. SBC had the most problems with the walls (banding) which is quite different from what I've experienced in the past (the other codecs all got better).
When it comes to close-ups, DivX3, RV9 and XviD keep the largest amount of details, with SBC exhibiting some blocks.
The rest of this chapter was pretty uneventful so I decided not to include another close-up shot. A note about the walls though: I initially started watching DivX5 and VP6 clips with the film effect enabled and the walls looked great. Turning off the film grain effect revealed imperfections on the walls but it might be an option you'll want to try out. XviD's film option has the same effect (the initial version of the DS filter I got had a really strong effect which negatively affected the picture, but in beta3 this is no longer a problem).
There's not much to be said for the next scene. Matrix wouldn't be Matrix without the lobby scene.
Then we have a close-up scene:
And on a final note to this chapter: If you see people up close you'll usually notice a lot of blocks in the background. This effect is most visible in SBC. Have a look at Neo's coat when you see him from behind, or when you see the close-up of one soldier shooting with at Neo with an M-16 rifle. And the elevator door looks blocky in SBC as compared to the other codecs. RV9's focus on foreground objects and keeping a rather static background pays off in such scenes.. you may notice the lack of detail when looking hard enough but it's not surprising that some people like RV9 a lot.. if you don't pay attention to details like the background RV9 makes the most harmonic impression but it's closely followed by XviD.
The last chapter has everything. Still scenes, scenes that will go from slow to action packed within seconds, a huge explosion, water, everything it takes to give a codec a good beating. First we start off with a still scene that once again exhibits what I mentioned in the first chapter. The elevator walls and the level indicator in the elevator are also interesting points. SBC performs worst in those areas, exhibiting visible blocks.
The next one shows how fast the bitrate can be increased to cope with a difficult situation.
Let's now conclude this chapter.
For the first time I'm doing this comparison I have gotten the impression that my source movie isn't hard enough. It has never been as hard to spot differences between the different codecs. I think that all of the presented codecs can be used for a DVD backup without too much concern.
I've divided the codecs in two classes: In class one we have the "details first" codecs: XviD, DivX3, VP6, 3ivX and ffvfw (in that particular order). XviD does the best job at keeping things non blocky. VP6 sometimes trades a few details against blocks (meaning the lack thereof), and ffvfw reminds me of early XviD builds - it still has a long way to go. 3ivX could use some improvements against those ugly looking textures I've mentioned before
In the other class we have the "no blocks first" codecs which are a bit less detailed: DivX5, RV9, NeroDigital (not necessarily in that order). Both DivX5 and RV9 have made improvements in the detail area (the latter more than the former) but you can still spot a lack of details every now and then (for DivX5 mostly during close-ups, in RV9 it's mostly during selected scenes that have a lot of motion). You can clearly spot that ND trades speed for quality but it's a fair trade and the results are still good.
As you may know, I value details a lot so for me XviD comes out on top in this test. However, I was impressed with the newcomer VP6, the improvements w.r.t. to details RV9 has made and NeroDigital's quality even though it's 10 times as fast as the slowest codec in the test. I'd suggest to give ffvfw and 3ivX some time before you start using them productively. Also, DivX3/SBC has definitely found its match by now.
Now let's move on to Saving Private Ryan. If you think you've seen enough you can proceed directly to the conclusion.
This document was last updated on January 20, 2004