http://bluray.highdefdigest.com/trainingday.html
In short, HD DVD wins.
The Video: Sizing Up the Picture
'Training Day' on Blu-ray has a lot to live up to. Had this title been released on the format before it hit HD DVD, it likely would not have come under nearly as much scrutiny. Videophiles are waiting with baited breath to see not only if 'Training Day' looks great on Blu-ray, but if it tops or at least equals its rival. Surprisingly, the differences between the two versions is substantial in more ways than one -- and unfortunately, it doesn't go Blu-ray's way.
But first, a note on this comparison. I hooked up both my Toshiba HD-XA1 HD DVD player and Samsung BD-P1000 Blu-ray player to my HP Pavilion reference HDTV via its two HDMI inputs. Note, however, that the first-generation Toshiba HD DVD decks are not capable of outputting native 1080p signals (unlike the Samsung), so it was up to the HP's internal processing to upconvert the Toshiba's 1080i signal to 1080p. Also, given the Samsung's much-publicized problems with its HDMI output (due to a reported faulty noise reduction chip that results in a degraded signal via the deck's HDMI out, Samsung is planning to correct the problem on future shipments as well as issue a firmware upgrade sometime this Fall), I also hooked up both the Toshiba and the Samsung via component out to ensure the most fair comparison possible between the two discs.
So, how do Blu-ray and HD DVD stack up? First, there was one noticeable difference between the two transfers I wasn't expecting. Both the Blu-ray and HD DVD are labeled on the back of their respective packages as being presented in 2.40:1, but that's not the actuality. The Blu-ray suffers from a narrower aspect ratio, with some noticeable cropping on the sides of the picture. Though the total screen area of the bottom letterbox bar is the same on both discs, the total screen area on the top letterbox bar is visibly smaller on the Blu-ray. A physical measurement off of my 65" monitor showed the top letterbox bar is reduced by a good one and a quarter inches on the Blu-ray. Meaning that the picture has either been reframed for the Blu-ray during the telecine process, or the Samsung is outputting a signal that slightly blows up the image. I estimate that about three to four percent of the area on the sides of the picture is lost on Blu-ray. Not that I also switched the outputs on both players into my HDTV to make sure it wasn't a problem with one of my set's HDMI or component inputs, but to no avail -- the Blu-ray was still cropped. Unfortunately, with no other Blu-ray player available in which to do a comparison, there is no way of yet telling if the altered aspect ratio on the Blu-ray is inherent to the encoded material itself, or a fault of the Samsung player's internal circuitry.
Next, to assess picture quality I did comparisons of three complete scenes on both discs, one after the other, simply by switching between my set's two inputs. I also compared a dozen individual still images, by pausing each deck on identical still frames and switching back and forth. And even the aspect ratio problem aside, the picture quality differences between the two transfers is often quite apparent. For example, during the very first shot of the film -- a zoom in on a red-hot, rising sun -- there some polarization was visible on the Blu-ray, with the banding of colors was obvious as the picture faded in. Though by looking closely at the HD DVD I could also spot some polarization as well, it was not as severe. These type of compression artifacts continued throughout both transfers, but again, I noticed about three or four shots on the Blu-ray with more polarization on backgrounds or during fades/dissolves, which were either not there on the HD DVD, or greatly lessened. So score points for HD DVD's VC1 compression codec over the MPEG2/AVC scheme used for Blu-ray, at least until that format's larger-capacity BD-50 dual layer discs become commercially viable.
Another difference between the two formats with 'Training Day' is that the Blu-ray transfer looks darker. Right from the opening scene when Ethan Hawke wakes up in his bed, the HD DVD exhibits an obvious (if far from extreme) brighter look. However, black levels looked comparable -- the HD DVD did not seem washed out versus the Blu-ray. And while the Blu-ray image still looks detailed, shadow delineation does appear a bit less impressive in the darkest scenes. Fall-off to black is a bit sharper on the Blu-ray, which is to be expected given its darker cast. Conversely, colors can appear slightly more vivid on the Blu-ray at first glance, though the actual saturation of colors appears equal on both. It is not that the HD DVD looks washed out, but the darker appearance of the Blu-ray transfer can make hues seem a bit more deep by comparison.
In all other areas, the two transfers are comparable. The sense of depth and detail of both formats can be terrific. While the brighter HD DVD is more consistent, especially on the darker scenes, the Blu-ray is no slouch. Indeed, anyone sitting down with either disc would, during a casual viewing, be quite impressed by either. But a head-to-head comparison is all about the small things, and given the aspect ratio issue with the Blu-ray disc, plus the compression artifacts and slightly darker cast, I would have to concede this first battle to HD DVD.
The Audio: Rating the Sound
The HD DVD release of 'Training Day' was only the second on the format to include a TrueHD Dolby Digital track (after another Warner title, 'Phantom of the Opera'). Unfortunately, due to disc space limitations, Warner has elected to drop the track altogether on the Blu-ray release. Of course, since there are currently no TrueHD-compatible HD DVD or Blu-ray players nor A/V receivers on the market that can even decode the format, as of this writing the question remains moot. But more troubling is that Warner has also dropped the Dolby Digital-Plus track off of this Blu-ray release, too -- the only format available is plain old Dolby Digital 5.1 surround. So instead of this Blu-ray sounding identical to the HD DVD, it sounds identical to the standard DVD released back in 2001.
As expected, 'Training Day's sound mix has a lot going on. Gunfire, explosions, a driving score and a hip-hop song or two -- it's all very precisely rendered. Dynamic range was excellent on the Dolby Digital-Plus track, with very defined and tight low bass and mid-range, and clear, distinct highs with little harshness. The same goes for the Blu-ray, though in a direct comparison of the film's two big action scenes -- the house raid and the final showdown -- the Dolby Digital-Plus still gets the edge. The soundfield is just more open in the rears, with plenty of ricocheting bullets bouncing around all five speakers, with imaging from the front to back channels sounding more natural and transparent. Low bass is also a tad stronger and tighter on the Dolby Digital-Plus, delivering more consistent deep frequencies. Overall, no, the differences are not staggering, but they are there if you listen close enough. A pretty big disappointment for Blu-ray.
In short, HD DVD wins.