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Set-Top DVD Recorders  (11/2002)

    by Douglas Dixon

Promise and Potential
DVD Formats, Again
DVD Recorder Basics

Pioneer -- DVD-R/RW
Philips -- DVD+R/RW
Panasonic -- DVD-RAM

Recording, 1, 2, 3
References

DVD has exploded in popularity in the past few years, as the set-top DVD player has joined the VCR next to the television in many households. There also has been a lot of excitement about using DVD on computers for desktop authoring and burning. But that's not all for DVD -- there is still another DVD-based consumer electronics product becoming available: DVD video recorders.

After all, VCRs are getting old, with the pain of shuffling videotapes to make sure the right one is inserted when you want to record a show. The new all-digital video recorders such as TiVo (www.tivo.com) and SONICblue ReplayTV (www.SONICblue.com) are great for grabbing your favorite shows, but then you have to watch them all, or lose them in order to make room for the next week.

DVD recorders seem to promise the best of both worlds: high-quality recording to the available space on a digital disc, combined with removable media that you can save to watch later, and for prices that are dropping under $1000. Yet the continued battle among competing DVD formats is limiting this potential.

   

Promise and Potential

Beyond consolidating a VCR and DVD player into one box, DVD recorders also offer other possibilities. In addition to recording TV shows off the air, you can record your own home videos to DVD, from analog or digital camcorders. You also can play the discs that you record on other DVD players, and on computer DVD drives. Since the video is in digital format, there is even the possibility of editing it on a computer.

However, all this promise and potential is not yet fully realized. Part of the problem is the continued confusion over competing DVD formats. And part of it is the trade-off between capability and compatibility, since supporting cool random-access recording features limits the ability to play the discs on other DVD systems.

But even with these issues, the current generation of DVD video recorders offers compelling features for time-shifting and saving videos on DVD discs. Just be sure you understand the different capabilities provided by the competing formats, and how they fit with your anticipated needs.

DVD Formats, Again

The mess over DVD formats still continues. Although the newer DVD players are starting to support a wider variety of formats, there are still two major competing camps, as well as sub-groups within each camp, so there is yet no possibility of universal DVD playback in sight.

The issue is over recordable DVD formats, discs that you can burn, either on a computer recordable drive, or on a set-top DVD recorder product. In the CD world, there are two recordable formats: write-once CD-R (Recordable), and CD-RW (ReWritable) that can be written, erased, and written over again. Since they cannot be erased, recordable discs are great for saving material permanently, while rewritable discs are good for temporary storage or updating over time.

These days you can expect that almost all CD drives can read both R and RW formats, both in computers and in audio CD (and DVD) players. But this almost-universal compatibility took a long time to settle down.

The situation with the relatively new DVD format is even worse, where there are two competing industry coalitions trying to establish DVD recordable formats.

The DVD Forum (www.dvdforum.com) specified the original family of DVD formats, starting with DVD-ROM for computer data and DVD-Video for prerecorded movies. The Forum defined two recordable formats similar to CD, DVD-R (Recordable) and DVD-RW (ReWritable).

       

The Forum also defined a third format, DVD-RAM (Random Access Memory), to provide the ability to access a DVD more like a hard disk. However, the DVD-RAM format is significantly different from the rest of the DVD family, and therefore cannot be played in other DVD drives unless they include special support for it.

   

These formats have been very successful. DVD-R has been used for several years for professional DVD authoring systems, and a consumer version became available in 2001 along with lower-cost DVD burners. DVD-RAM has found a niche for computer data storage, and also has been used in camcorders with a half-size disc format. DVD-R is compatible with most DVD players, and DVD-RW is less compatible, especially with older players.

Meanwhile, a second group, the DVD+RW Alliance (www.dvdrw.com), developed a competing rewritable format, DVD+RW (called "plus", in contrast to the DVD Forum "dash" or "minus" formats). The idea behind DVD+RW was to combine the capabilities of DVD-RW and DVD-RAM into a single format that both supports fast and flexible rewriting and is highly compatible with existing players.

       

More recently, the Alliance announced an additional DVD+R recordable format for write-once use, and the first products supporting both formats are appearing in the first half of 2002.

DVD Recorder Basics

The basic features of most DVD recorders combine the off-air recording capabilities of VCRs with the playback capabilities of DVD players, for prices that are dropping under $1000.

Like VCRs, DVD recorders include a built-in television and cable tuner for recording live broadcasts, and features like VCR Plus+ to simplify timer recording. Also like tape-based recorders, they offer a range of recording times, typically ranging from 1 to 6 hours, with a corresponding trade-off in image quality due to the reduced data rate.

Unlike with videotapes, however, DVD recorders can start recording instantly, without the need to fast forward or position a tape, as long as there is available unused space on disc. Even better, the playback can be instant too, without having to wait to rewind a tape. And with the use of DVD menus and chapter points, you can jump directly to a program on the disc without needing to visually scan through a tape to find it.

For recording from both older analog sources and the new digital video camcorders, many DVD recorders provide analog inputs, and also an IEEE 1394 interface (also called FireWire or i.Link) to input video from a DV or Digital8 camcorder.

DVD recorders use the same digital media formats as commercial DVDs, including MPEG-2 for video and often Dolby Digital AC-3 for stereo audio. They include hardware to convert the input video to these compressed formats in real time.

Since DVD recorders also are DVD players, they can include advanced player features such as progressive scan video output, built-in Dolby Digital (AC-3) and DTS (Digital Theatre System) audio decoders, and higher-quality video and audio inputs and outputs, including component video and coaxial and optical digital connections.

Since the discs created on these DVD recorders can be played on some computers and DVD players, these products can create a DVD menu to access the recorded clips. Menus can include the channel number and time that a clip was captured, and a title input by the user. Even better, some recorders can automatically create index menus with thumbnail images of each segment on the disc.

Finally, by using rewritable discs, DVD recorders can provide editing features for the segments that you record on a disc, depending on the disc and recording format. You can delete a segment, of course, and rearrange the order of the segments in the disc index. With some formats you can append to a segment, or divide a segment, or add additional chapter points. You also can create a play list to play through some of the segments in a specified order.

Pioneer -- DVD-R/RW

Pioneer Electronics (www.pioneerelectronics.com) has been the driving force behind DVD-R/RW, introducing the first DVD-R burners for professional DVD authoring, and then kick-starting desktop DVD authoring with new generations of low-cost burners for general use.

Pioneer launched its first DVD-R/RW recorder for the U.S. market, the Pioneer Elite DVR-7000, in fall 2001. This is a video enthusiast product, with high-end features including a time base corrector and progressive scan output, for $2,000 (MSRP). Pioneer also launched a professional DVD-R/RW recorder, the PRV-9000, in November 2001 for $2,050.

   

These units support two recording modes, a Video mode for both DVD-R and -RW for best compatibility with DVD players, and a Video Recording (VR) mode that provides more flexibility for rewritable DVD-RW discs, but with less compatibility. IN both modes, you can create and edit a title list menu to index each clip on the disc, although the menu is text only.

Video mode recording on the DVR-7000 offers up to 2 hours of recording time and is playable on regular DVD players (after finalizing), but has limited recording and editing features.

VR mode recording can only be used on DVD-RW discs, and offers between 1 and 6 hours of recording. The recordings can be edited, but are not playable on regular DVD players.

In Video mode, chapter points are inserted automatically at regular intervals. In VR mode, you can use a visual Disc Navigation Mode to view your clips as thumbnails, erase clips, add chapter points, and create playlists.

Much like "closing" a recordable CD, you must finalize a Video mode DVD-R/RW disc in order to be able to play it on a regular DVD player or computer DVD drive. This writes all the necessary control information to the disc, and adds a main menu. Once a disc is finalized, you cannot edit or add more material to it. THe amount of time required for finaalization depends on the disc mode and the amount of recorded material. Video mode discs can take up to 20 minutes to finalize, and VR mode discs can take up to 1 hour

Philips -- DVD+R/RW

The DVD+RW Alliance designed the newer DVD+RW format to provide editing features without the compatibility issues and confusion of a separate VR recording mode, and without the need to finalize some disc formats.

Philips Consumer Electronics (www.dvdrecorder.philips.com) introduced DVD+RW recorders in 2001, the DVDR1000 and DVDR1500, but these only supported the +RW format. A new recorder also supporting DVD+R, the DVDR985, was scheduled to ship in May 2002, for $999 (MSRP).

   

The "plus" recorders can automatically create an index menu with thumbnail pictures of each clip on the disc. You can edit from this menu, to append, divide, and erase the scenes. You can hide and unhide individual clips to be skipped when you play the disc.

The DVDR985 can record at four rates: 1 hour at high quality (9.73 Mbps), 2 hours at standard quality (5.07 Mbps), and 3 and 4 hours for extended recording (3.38 and 2.54 Mbps).

By adding support for the write-once DVD+R format, the recorders permit you to make permanent recordings, without the possibility that they can be erased and rewritten. But since the format is not rewritable, there are some differences in how such discs are used. In particular, DVD+R discs must be finalized before they can be played on regular DVD players. You can perform some edits after recording and before finalizing, but they will not be available on regular DVD players.

While DVD+RW discs do not need to be finalized, if you have performed edits on a rewritable disc then you still need to instruct the player to perform a similar process to make it compatible with regular players. If a disc will not play on regular players, and/or was created on a different brand of recorder, you also can have the player perform several different adaptation processes to try to modify the disc for better compatibility.

Panasonic -- DVD-RAM

Meanwhile, Panasonic Consumer Electronics has been promoting the DVD-RAM format for both computer and consumer products, since it offers much more convenient random access, like hard discs. The trade-off with DVD-RAM is that it is compatible only with players that explicitly support the -RAM format, and that the discs are stored in a separate caddy.

Panasonic (www.panasonic.com/consumer_electronics/dvd_recorder) introduced the first DVD recorder, the DMR-E10 at the end of 2000 for $3,999 (MSRP).  In late 2001, Panasonic introduced its second-generation recorder, the DMR-E20, priced at $1499 (MSRP) but available for under $999. This new recorder added DVD-R recording capability.

   

You can record 1, 2, 4, or 6 hours, or up to 12 hours on double-sided DVD-RAM discs.
The -RAM recorder offers simple video editing, including rearranging the order of scenes, skipping unwanted scenes, and copying selections, to create custom playlists of favorite scenes. The recorder also offers a Flexible Recording mode, which will select the best picture quality possible for the recording time and available space on the disc.

But the most impressive feature of the DVD-RAM recorder is the time-slip function, controlled by a roller on the front of the player. The disc access rate of the -RAM disc is fast enough that you can record and play back material from the disc simultaneously. This is not just recording one program while watching another. This means you can be watching a show, take a phone call, and then continue watching from where you left off, even while the rest of the show is still being recorded. You can even scan though the recorded section in a small on-screen window.

The DVD-RAM format also has found a home in digital camcorders, using a half-size disc format that also can be played on set-top DVD-RAM units. The Panasonic VDR-M10 offers up to an hour of MPEG-2 video recording for $2499 (MSRP), plus the direct access and editing capabilities of the -RAM format. Hitachi also has been a leader in DVD camcorders (www.hitachi.com/dvdcam), and is introducing a dockable DVD-RAM recorder for professional cameras in fall 2002.

Recording, 1, 2, 3

While DVD recorders would seem to be a natural set-top accessory, unfortunately the market is confused by all these different formats, and even modes within formats. But we can make at least some sense out of this.

If you want to record off-air material and watch it later, like a disk-based video recorder, then go ahead and use rewritable media. The DVD-RAM format provides the most flexibility for this use.

If you want to make permanent recordings from your old videotapes, then record direct to write-once media, with chapters and a main menu. DVD-R recorders are certainly highly compatible, and the new DVD+R format shipping in the first half of 2002 is promised to be the same.

It's the in-between uses that cause the confusion: recording material and then editing it, saving some clips and deleting others, or deciding after recording that you want to save the disc. In these cases, no matter the format, you will need to may more attention to the recording mode. DVD-RW is more and more compatible with newer players, but you need to trade off editing capability and compatibility with the VR and Video modes. DVD-RAM is the most flexible, but requires players explicitly supporting that format. And the newer DVD+RW format promises both: clip-based editing features and at least reasonable compatibility.

Just as with the early years of CD, the recordable DVD format mess will take years to shake out. But you can still have fun with today's DVD recorders, both for time-shifting TV broadcasts and saving your old tapes to digital discs.

References

DVD Forum
    www.dvdforum.com

DVD+RW Alliance
    www.dvdrw.com

DVD+RW Resources
    dvdplusrw.org

Panasonic Consumer Electronics 
    www.panasonic.com/consumer_electronics/dvd_recorder

Philips Consumer Electronics
    www.dvdrecorder.philips.com
    www.dvdrw.philips.com

Pioneer Electronics
    www.pioneerelectronics.com

Hitachi Denshi America
    www.hitachi.com/dvdcam

Samsung Electronics
    www.samsungelectronics.com/dvdp/dvd_recorder

SONICblue ReplayTV
    www.SONICblue.com

TiVo
    www.tivo.com