Adstech DVD Xpress 2.0 MPEG2 encoder decoded

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Product: DVD Xpress 2.0 (USBAV701)
Company: ADS Technology
Web : www.adstech.com
Requirements : Pentium III (or higher) PC, one spare USB 2.0 port, DirectX
Platform : Windows 98SE/ME/2000/XP
Price : $71 to $99 US dollars (~£46 GBP)

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THANK GOD the VCR is dead, our Marc Ninthly exclaimed recently. Well I have an answer for his question on what to do with the "copious amounts of tapes filled with our fave series" left by the VCR era: I'll begin digitizing my entire collection of VHS tapes to DVD-R media using a small external device that I can easily hook up to my notebook's high-speed USB 2.0 connectors: The DVD Xpress 2.0 from ADS Tech.

About the size of a 4-port USB hub and powered by one tiny 110v to 3.3v power brick, it promises effortless MPEG1 and MPEG2 digitizing of an analogue video signal coming from any video playback device with RCA composite video or s-video output connectors. It handles NTSC, PAL or SECAM signals, and digitizes audio on the same device (using its own stereo RCA audio inputs, not using your computer's sound card at all).

Installation and use

Install was flawless on WinXP home. You plug the device to your computer's USB 2.0 port, it's recognized, the computer prompts for the drivers location, you insert the CD, the drivers and software are installed, and you have to reboot. One small issue to note is that the installer attempted to launch a DirectX installer of a version lower than what I already had on the system (DirectX 9.0c), so I just aborted the DirectX installer. Everything works fine with 9.0c. It's a good opportunity to repeat here what I always tell everyone: it's better to check the manufacturer's web site for the latest drivers and software and use that instead of what comes on the cd bundled with your hardware.

The bundled video capture application is Capwiz version 3.1 dated February 2004. If you check the Adstech.com web site you can find Capwiz 3.5, which adds "on the fly" capture and burning to optical media, as in "direct-to-cd" and "direct-to-dvd" capture. Last month when I started playing with DVD Xpress 2.0, Capwiz version 3.5 for the DVD Xpress 2.0 hardware was still in beta testing and ADSTech warned me in no uncertain terms that there were still "stability issues". "Note that many customers have reported stability problems with this version so if you have any problems with it we strongly recommend getting rid of it and going back to version 3.1" tech support warned on November 5th, so I decided to avoid it. As of late December their web page shows no beta notice next to the 3.5 version listed, yet the file seems to have a mid August date, making me wonder if it's really any different from the pre release 3.5 version I was once warned about. Caveat emptor.

Version 3.1 of Capwiz, still offered on the site and I guess for a reason, seems to have everything a user might need, without "feature bloat" or "instability" warnings. Speaking of which, a new beta version of Capwiz 3.6 has been released in mid-December, adding yet more features to the mix like "direct capture into DivX" (mpeg4). As many of you might realize, this defeats the purpose of the built-in hardware mpeg2 encoder chip, and sends CPU requirements through the roof because it's your CPU which must do the work of converting dvd-quality MPEG2 video sent by the device into MPEG4 video, thus raising the recommended cpu from a below-Ghz PIII to a 2.4 Ghz Pentium 4. You might as well be using a $25 tv tuner card for that kind of cpu-intensive, software-based mpeg encoding work. Marketing drones, I've heard of them. ("We need to add mpeg4, everyone is talking about it" I imagine them demanding the software developers over a Dilbert-style conference table).

Capwiz shows upon start a series of "wizards" styled dialogs asking you the video format used as source (NTSC, PAL or SECAM), the video input port that you're going to use (Composite video or S-Video) and the compression format that you wish to use (Video-CD standard MPEG1 or DVD-standard MPEG2). The last dialog also shows a useful estimate of the maximum recording time possible at the selected format, based on the free space available on your hard drive. In the case of MPEG2 dvd-quality video, an estimate of 4mb/s is used for the calculation.

Even a child can follow the dialogs

You can choose between composite video or S-Video inputs

The unit supports MPEG1 and MPEG2

The Capwiz 3.1 software takes the whole screen, as is very easy to use. After you press Play on the VCR or other video playback device (it could be a Laserdisc player - I have one of those ancient beasts!), the DVD Xpress 2.0 attempts to "sync" to the video signal. You'll notice this by the blinking green led on the unit's front. After it has synched with the signal, you'll see the blinking stop and the led will stay solid green -for as long as there's a valid video signal being received-. This can be one source of confusion -or problems- because such "synching" takes time, so you better have a few seconds of stable signal taped before what you want to digitize appears in your vhs tape, otherwise you'll lose the first 3-4 seconds of your capture. A work-around involves pressing play, pause on the vcr, then starting capwiz and the capture process, with the unit already "synched" to the paused image, then make the vcr continue playing after mpeg2 recording with Capwiz has started.

The "preview" button is your friend, use it often. While previewing the signal being received by the DVD Xpress, you can use the Brightness/Color button at the top bar to modify video signal parameters on the fly, adjusting the image quality to compensate for too bright, too dark, or other defects in the source material. Once you start recording (by pressing the red REC button on Capwiz that looks just like the one in a VCR), every time you stop and continue recording, a new video segment is created, with an incremental filename. So if you started with "mywedding.mpg" and stopped three times along the digitizing process, you end up with filenames "mywedding.mpg", "mywedding2.mpg" etcetera.

The top and bottom bars in the Capwiz software. Preview video is shown right in the middle.

ADSTech includes Ulead's "VideoStudio 7 SE" for video editing work, which can be launched from Capwiz or used after-the-fact to add bells and whistles to your digitized video files like transitions, text-overlaying, etc. I've found Ulead VideoStudio 7 to be a poor choice, for a number of reasons: 1. It's too complex for the novice users. 2. It feels like a slow, bloated application (probably because it is). 3. It's a full-blown video editor, overkill for what most users might want/need to do. 4. It's CPU intensive. ADStech could have done a favour to most users by simply including a simple video cutter/joiner like VideoRedo, that fits the needs of most of the people who just wants to digitize their tapes, instead of a 800 pound gorilla that even needs multiple huge patches installed. For those that need the features of Ulead VideoStudio like inserting fancy transitions between scenes, a discount coupon for VideoStudio could have been fine. Some of you, however, might want to follow my advice and completely ignore VideoStudio and burn the created .mpg files from Capwiz directly to dvd-r media.

Ulead VideoStudio 7 SE, the huge bundled video editor

The autopsy
I advise non-geeks to jump straight to "The Verdict" and skip this section. I couldn't resist the temptation and opened the unit to see what is the MPEG2 encoder chip used. So for those geeks reading us we'll perform an autopsy of the guts of this beast. There are only a handful of chips inside the tiny plastic case, the main one being the Cirrus Logic CS92199 which is the brain of this beast. The CS92199 is nothing more than a very fast DSP (Digital Signal Processor) doing the real-time MPEG-2 audio and video encoding. According to the chipset docs it's "optimized for low-bitrate video encoding (2 Mbps to 4 Mbps)" it includes frame and field motion prediction and "proprietary rate control algorithms". You can find the official chipset brochure here

There are two other ICs, first a CY7C68013, a single-chip USB 2.0 controller from Cypress Semiconductor, basically this moves data between the device and the computer over the USB bus at USB 2.0 speeds. Curious geeks can find the chipset data over there, and also noticeable is a small 8MB of memory (used for buffering, I bet) in a single SDRAM IC. It's a Winbond W986432, apparently running at 166 Mhz.

The last chip that stands out in the tiny circuit board is barely noticeable: a TVP5150a, made by Texas Instruments. This one, smaller than a your little finger's nail, is the chip responsible for digitizing the analogue video signal, and passing it to the Cirrus Logic MPEG encoder. While looking at the chipset data sheet, I couldn't find any reference to PAL system sub-flavors, just the generic "PAL" (which often means just the Euro flavours of PAL: B, G and I, used across Europe and its areas of influence).

American readers might not be interested to know that there's half a dozen sub standards of PAL: like PAL/N used in Argentina and other countries in South America, and PAL/M, used in Brazil. The only difference between the British Pal (B) and the N and M ones is the frequency of the colour (chroma) frequency.

That certainly might explain why my attempts to digitize N-PAL videos came out with a B&W image. I had to insert a PAL/B-to-PAL/N converter box in the middle to solve the PAL/N issue. If this is a software or hardware issue, I'm still not sure. But in case it's a hardware limitation, one can only wonder why can't Texas Instruments design a chipset that works on all 5 most common PAL flavours (B-G-N-M-I). Even the cheap PCI TV tuner cards that you can buy for $25, featuring an ages old Brooktree/Conexant chipset feature full N-M-B-G-I PAL support. This will be a non issue however for those of you in Euro-land or North America. With this we end the autopsy. Wash your hands on the way out.

A random rant about external USB devices
Why can't manufacturers realize that some of us value a good solid metal case, which provides adequate RF shielding, and if grounded, protects it against death-by-ESD (electro-static discharge), not to mention good heath dissipation?. This device, like 99.9% of the inexpensive external USB 2.0 devices, doesn't follow any of these guidelines, which is ok, 99% of the time. And don't get me started on the idea that USB devices don't need an on/off switch. Just because I leave something plugged in it doesn't mean I want the device to be active, sucking up power all the time.

The verdict
Besides the described little annoyances that are shared by most of today's external usb 2.x peripherals -like the lack of a power switch-, I give this unit 4 Fernandos in my one-to-five personal rating scale. It delivers what it promises... decent quality hardware MPEG2 encoding for common people (people doing professional video work will surely need a higher-bitrate capture board). And it comes at a price that anyone can afford. I transferred 6 movies, four of them in PAL and two in NTSC, of which one was an original and another was a taped TV program sent by a friend in the States. I'm satisfied with the unit's performance. URLs for two sample video clips (NTSC and PAL) are available for those interested in seeing the image quality.

Specially because its hardware based encoding design means that while digitizing video it doesn't hog your PC's cpu nor does the resulting file need any post processing. I repeat my personal words of advice: the bundled Ulead editor is a big pain in the back end. If you just want to do quick edits and cut scenes out pretend that the included Ulead software is missing and install VideoReDo instead. See the VideoReDo review we did recently for an explanation of its key features.

On the plus side: unlike other devices that process audio separately using your PC's sound system, the DVD Xpress 2.0 features its own audio inputs so there's virtually no chance of getting "audio/video sync" problems. Did I just hear someone yell you "what are you waiting for, to get rid of those VHS tapes?", eh? µ

See Also:/B>
VideoREDO brings fast MPEG1/2 chopping