Upconverting DVD players and Blu-ray

Several years ago, relatively obscure companies like V. Inc. and Momitsu released DVD players that more or less revolutionized the industry. They had developed DVD players that would output a purely digital signal via DVI (later HDMI), internally scaled to 720p or 1080i, in addition to the familiar 480p that we had gotten from progressive scan DVD players for some time.

These players generated a lot of buzz and were an instant hit, and why not? The promise of high definition quality from a relatively inexpensive DVD player was a seductive idea for most consumers. The market responded and fairly soon the big boys got into the upscaling DVD business. When Denon (a traditional leader among DVD manufacturers) announced their line of upscaling players you knew that this technology was here to stay.

From what I've seen this represents one of the biggest bamboozelments in consumer electronics history. Yes, in theory a DVD player that outputs a digital signal should provide a better picture. After all, the data is stored on a DVD digitally. Therefore, outputting the data digitally skips an otherwise necessary digital-to-analog conversion, and the signal should be a more accurate representation of the original. Furthermore, if the image is already scaled to the native rate of your display, then this can bypass your display's own internal scaler, which should also yield a better picture.

That's the theory.

However, real-world experience turned out somewhat differently. There are some devices that provide a superior image over its digital output. The Toshiba HD-DVD player is a good example of this. Just about everyone agrees that the HDMI output is a little sharper. However, with standard DVD players this not always the case. In fact, it is not clear to me that this is even true a majority of the time. The component output is perfectly capable of transmitting the full 720x480 resolution of the DVD format, and to my eyes the performance of component output is often better than the digital output. I have no technical explanation this, but it is often true. Finally, the scaling just isn't a major issue. Perhaps test patterns would show some minor difference, but I've never seen a readily-visible performance increase from an image that is scaled in the DVD player rather than by the display.

If flashy features like an upscaled digital output doesn't make much difference to picture quality, then what does? As usual, it's the boring stuff that marketing campaigns have a hard time finding slogans for. First, the quality of the DVD player's deinterlacer makes a huge difference in picture quality. There are a few displays that will deinterlace a 480i signal and produce as good or better an image than it would if it had been fed a a 480p signal, but usually not. Unlike upscaling, progressive scan DVD players were a real breakthrough. Second, good old fashioned core video performance makes an enormous difference. Does the player offer a flat, extended bandwidth, does it track the range from black to white accurately, and does it suffer from visible y/c delay? These are all performance characteristics that really matter.

If a DVD player uses a top-notch deinterlacer and has good core video performance, then it's going to produce a great image. Whether that image is transmitted over HDMI or component or whether it is "upscaled" really doesn't much matter.

Take my once (and still) favorite DVD player, the Panasonic S97. If you have access to this player, try the following experiment: Once you get the levels set properly, go back and forth between the component 480p output and the HDMI 720p or 1080i output (depending on the resolution of your display device). If you think that the digital 720p/1080i HDMI output looks visibly better, then you see something that I cannot.

Blu-ray

With the advent of truly high-definition players, the situation has changed dramatically.

First, with the proliferation of 1080p displays and 1080p content, scaling has become much less of an issue than it was in the days in which people had to scale 720x480 DVD up to match their 1280x720 display.

Second, although component does a perfectly adequate job of transmitting a 480p signal, it rarely is up to the task of transmitting 1080i and it won't transmit 1080p at all.

Third, Blu-ray contains new high-resolution codecs that can only be transmitted without down sampling via HDMI or 5.1 discreet audio. This renders then once ubiquitous digital coaxial or fiber optic cables obsolete.

Fourth, because of (2) and (3) we have entered an era in which having an HDMI connection on the display and on the receiver or pre-pro is a necessity for good home theater performance. Only HDMI will transmit the full 1080p video signal along with the high-quality digital audio that Blu-ray provides. Component connections have thus also become obsolete.

Fifth, the biggest problem with Blu-ray players is not their Blu-ray video performance. This is almost always superb. We now must worry about subsidiary issues, such as:

• Does the player internally decode high-quality lossless audio codecs, such as Dolby TrueHD and DTS-HD Master Audio, and submit the data via PCM through HDMI?
• Does the player have reasonable start-up and load times?
• Does the player offer high-quality DVD deinterlacing? Many of the earlier Blu-ray players focused almost exclusively on HD performance and neglected to provide quality processing for DVD sources.