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NVIDIA has been a leader in the gaming graphics cards market for a long time already. Some of you may like it, some of you may not, but this fact is undeniable. Sometimes, NVIDIA had even to compete with itself because there were no worthy competitors capable of opposing NVIDIA's offsprings with something really powerful. The manufacturers showed off sporting new modifications, tried to attract the customers by useful functions and incredible PCB colors, but it was the competition among graphics card makers, and not among chip developers, as all these cards were all based on NVIDIA solutions.

We don't know what stimulated NVIDIA to start working in new directions. Maybe the company simply got tired of monotony, maybe they felt pretty cramped in the current graphics market. No one knows… But they did start developing new territories.

Using the experience they accumulated when developing leading 3D graphics chipsets, NVIDIA introduced nForce, a Socket A mainboard chipset with the integrated graphics core and a powerful sound core. To all appearances, the company's first experience in a new sphere of hardware industry appeared a success, so now the new chipset is in the final "polishing" stage.

But let's return to graphics cards. As we see it, NVIDIA should be very happy with the state of things here: the company offers great solutions to meet all the users' needs and demands. Very fast and expensive gaming chips? - Here you are. Low-cost gaming solutions? - No problem. Something for office needs? - Of course! With dual-monitor support? With a Video-In, Video-Out, digital monitors support? - Everything you can think of!

To complete this ideal picture they would only need an "all-in-one" solution with all sorts of Ins and Outs and a TV-tuner onboard. For example, 3dfx used to have a card like that in their product range; Matrox has this kind of solution; ATI - also, of course. And the launching of the new RADEON 8500, which was as usual used by ATI for its cards with a TV-tuner aboard (All-In-Winder RADEON 8500DV), was very likely to have pushed NVIDIA to urgent actions.

On August 27, 2001 NVIDIA announced Personal Cinema:

This small box, which besides the common functions comprises a TV-tuner, is NVIDIA's first move in this new field. The company took a way different from that of ATI, Matrox and 3dfx. They decided not to integrate a TV-tuner onto the card but designed it in a separate casing. Now we have a great opportunity to find out what has come out of it.

But before we start we would like to thank VisionTek Company for the brilliant opportunity to take a closer look at this new solution from NVIDIA. They were the first to introduce their product based on NVIDIA Personal Cinema.

VisionTek Xtasy 5564 Everything: Closer Look

Like all VisionTek graphics cards based on NVIDIA Titanium chips, which we have already discussed in great detail in our review called "VisionTek Xtasy Family: First Mass Graphics Cards on NVIDIA Titanium", VisionTek Xtasy 5564 Everything is shipped in a very originally designed box:

The package contains a smaller green box called AV/Tuner Box (later on we will call it just a "TV-tuner" or simply "tuner"), tuner remote control unit, Xtasy 5564 graphics card based on NVIDIA GeForce2 MX 400, a set of cables and converters, a CD with the drivers and other software, the user's manual and batteries for the remote control unit.

Now we would like to dwell on the package items in a bit greater detail. The graphics card on GeForce2 MX 400 chip is equipped with 64MB graphics memory by Samsung with 6ns access time:

The card is actually quite ordinary, so we won't say a lot about it. The only thing, we would like to point out so far is that it is equipped with a Video-In and a Video-Out, due to Philips SAA7108E chip encoding and decoding the TV-signal:

The remote control unit fits very comfortably into your hand and doesn't arouse any complaints at first glance. All the buttons on the unit are marked, so you can get their meaning and functions right away. The only drawback we noticed has to do with the buttons location. Those located in the lower part of the remote control unit are very convenient to press, while the ones in the upper part of the device are a bit hard to reach without rearranging the unit in your palm:

TV-tuner is the most important part of the Xtasy 5564 Everything set. It looks very unusual: a semi-transparent plastic casing with NVIDIA logo on it, which allows you to see some internal fragments:

Inside the casing, there is a PCB with a laid out Radio Frequency (RF) shielded module, infrared remote control sensor, logic and commutation circuits. To make a picture we removed the shield from the RF module:

   

The graphics card controls the tuner via a special control cable along the I2C bus developed by Philips. By the way, the logic as well as the RF module are both based on Philips chips. And the graphics card from this set also features a Philips' TV-chip. Philips is everywhere :)

But back to our TV-tuner. The module is equipped with the following connectors:

  • Radio frequency Input port for TV-antenna or cable;
  • S-Video and composite In for video signals;
  • S-Video and composite Out for video signals;
  • Line-In for audio signals;
  • Line-Out for audio signals;
  • Control cable connector.

The functions of all these connectors and ports are more or less clear. The only thing that may arouse a lot of questions is the control cable connector and the cable itself.

The video signals go along the separate screened wires of the cable from the input ports of the tuner to the graphics card and back. In fact, when no TV-signal is received, the module is "transparent" for the video signals and works simply as a sort of converter.

When the tuner is on and receives TV-signals, the output video signal from the RF module goes along this cable to the video-In of the graphics card and there it is encoded into digital format by the graphics chip.

Besides, the cable also contains some wires to power and control the tuner.

It seems that the module was worked out to support FM-radio functions as well, but the piece we had at our disposal didn't have FM electronics components and the spot under "FM" mark was left empty:

It is also worth mentioning that NVIDIA's tuner has a very unusual connector for the TV-antenna, which may cause some difficulties. To understand what we mean, please, compare the RF module and antenna connector of NVIDIA Personal Cinema and AVerTV:

At first sight the RF parts of both devices look very similar. However, if you take a closer look at them, you will notice that the chips are different, though both of them are produced by Philips.

Drivers and Software

When NVIDIA Personal Cinema is installed there appear the following new items in the Device Manager:

Together with the drivers you install InterVideo WinDVD, WinDVR and MGI VideoWave 4 for video capture and editing.

InterVideo WinDVD is a software DVD-player. Actually, there is nothing so very special about it, except the remarkable control panel:

InterVideo WinDVR, which control panel is designed in a similar way, is the one to control the tuner:

To provide comfortable operation it offers a number of functions, but not all of them work correctly. For example, "Timeshifting" doesn't work at all. The main idea of this function is to delay the image display and sound playback relative to the translated signal. It works when the data is stored in the buffer "on the fly" and then played with a certain delay, i.e. with the shifted time. With this function enabled, you can go away from the monitor for a couple of minutes and miss no valuable info. To our great disappointment, InterVideo WinDVR doesn't work correctly with the timeshifting function now, so we failed to feel all the advantages of this thing.

WinDVR, like any other TV-tuner control utility, boasts a great lot of settings, which are all put onto the general settings page.

The Channels page allows auto scanning the entire TV band, selecting the channels you prefer and naming them to your own liking:

The Display page allows you to set some display parameters:

TV page is responsible for TV-standards. Here you have only to select the country and all the other parameters will be set up automatically. However, manual setting is also possible:

The video capture and saving parameters can be changed on the Record page (we will tell you more about video capturing later in the article):

On the Storage page you can set the storage location for the recorded files:

Well, as we have already told you we will return to video capturing a bit later and now it's high time we ran some tests.

Testbed and Methods

To consider the TV image quality we used the following hardware:

  • MATROX Marvel G450 eTV graphics card, RF module by Samsung, S5D0127X01 video decoder is also made by Samsung.
  • AVerMedia AVerTV model 103 TV-tuner, RF module by Philips, Conexant FUSION 878A video decoder.
  • Samsung CS-25D4 R TV-set.

The tests were run with the common antenna connected to the TV-set.

Unfortunately, during our tests the signal quality left much to be desired that is why the testing conditions didn't allow us to get impeccable quality of input signal. Anyway, all the participants were tested in the same conditions that is why the results and conclusions are pretty objective.

To estimate the image quality, which could be seen on the TV screen we connected the composite video-Out of the TV-set to the composite Video-In of NVIDIA Personal Cinema TV-tuner. In this case the RF front-end section of the TV-set played the role of the RF module and SAA7102 chip of the Xtasy 5564 Everything card was responsible for the translation of the signal into digital format.

TV-Signal Reception Quality

To compare the TV-signal reception quality provided by the tested TV-tuners we resorted to three "control" channels, which could be easily adjusted for all TV-tuners and were received stably enough.

  • At first comes the 4th channel of the Russian television. When we were in the middle of the tests, the program got suddenly interrupted and we could see the tuning scheme. Here are the captured images for each testing participant:
Matrox Marvel G450 eTV


AVerTV 103


NVIDIA Personal Cinema


Samsung CS-254D R TV-Set

As you can see from the images above, the RF-module of NVIDIA Personal Cinema seems to feature the lowest sensitivity that is why the provided image quality for this channel turned out worst of all. Another possible reason is inaccurate tuning to the channel frequency. Unfortunately, NVIDIA Personal Cinema doesn't allow any manual tuning.

The quality provided by AVerTV 103 appeared much better, though the picture was spoilt slightly by some background noises.

G450 eTV boasts good noises filtering and seems not to smoothen the image at the digitizing stage, which makes a subjective impression of considerably higher image quality. However, some minor details may get lost in this case: see the absence of thin white diagonal lines inside the two black rectangles located to the left and to the right from the center.

The image provided by the TV-set itself appeared the best of all, though it is also not absolutely ideal: you can see some bluish tails near the darker fields.

  • Then comes the 3rd channel of the Russian television. The signal quality is simply awful.
Matrox Marvel G450 eTV


AVerTV 103


NVIDIA Personal Cinema


Samsung CS-254D R TV-Set

No wonder happened: neither TV-tuners, nor TV-set managed to provide an acceptable image. You can clearly see that all the tuners except AVerTV 103 filter the image so that the noises look like dark and light spots. While in case of AVerTV 103 the image turns out a mixture of various horizontal lines.

  • Well, let's stop jeering at the TV-tuners. Now it's high time we checked what would happen in favorable testing conditions. The images below show the best quality we managed to obtain for each piece:
Matrox Marvel G450 eTV


AVerTV 103


NVIDIA Personal Cinema


Samsung CS-254D R TV-Set

Matrox Marvel G450 eTV proved just excellent. We don't have any comments to make here.

AVerTV 103 displayed numerous colored lines over the entire image even in case of good signal received, having revealed low sensitivity of the RF module as well as a number of drawbacks of Fusion 878A chip responsible for signal digitizing.

As for the FR module of NVIDIA Personal Cinema, it also suffers from some drawbacks: you can see red tails and rippling effect.

The image quality obtained on the TV-set only turned out just brilliant. By the way, it is undoubtedly NVIDIA Personal Cinema that deserves the praise for that, because we used the TV-set only as an RF module in all our tests and the conversion from analog to digital format was performed by the joint offspring of NVIDIA and VisionTek. Note that even though the lady in the movie we captured this picture from was gesticulating very actively, there appeared no interlacing effect, which is very typical of the cases when a video stream with interlaced scanning displayed on a device with progressive scanning. In other words, Philips SAA 7108E chip of NVIDIA Personal Cinema copes well with this task.

Well, in our review you have come across numerous terms, such as interlaced and progressive scanning, interlacing effect, and some others. In case you are not quite familiar with them, we suggest reading on. The next part of our article will guide you into some secrets of television.

How TV Works?

TV image is translated and displayed on the TV-sets line by line.

This is currently done with a cathode-ray tube, which contains an electron gun that must be operated at a high voltage. The electron gun shoots a high-energy beam of electrons toward a phosphorescent screen, creating a bright spot that appears where the beam hits the screen.

In a black-and-white TV, the screen is coated with white phosphor and the electron beam "paints" an image onto the screen by moving the electron beam across the phosphor a line at a time. To "paint" the entire screen, electronic circuits inside the TV use the magnetic coils to move the electron beam in a "raster scan" pattern across and down the screen. The beam paints one line across the screen from left to right (according to European standards it takes 52 microseconds). It then quickly flies back to the left side, moves down slightly (which takes around 12 microseconds) and paints another horizontal line, and so on down the screen. Like this:

In this figure, the blue lines represent lines that the electron beam is "painting" on the screen from left to right, while the red dashed lines represent the beam flying back to the left. When the beam reaches the right side of the bottom line, it has to move back to the upper left corner of the screen, as represented by the green line in the figure. When the beam is "painting" it is on, and when it is flying back it is off so that it does not leave a trail on the screen. By the way, the current TV standards allow making efficient use of the short intervals when the ray is off. It is possible to fill these intervals with small portions of digital info, such as text or captioning data. And it doesn't have any negative influence on the image quality, as the TV-set simply cannot display this data as a part of image because the ray is off.

As the beam paints each line from left to right, the intensity of the beam is changed to create different shades of black, gray and white across the screen. Because the lines are spaced very closely together, your brain integrates them into a single image. A TV screen normally has 525 lines visible from top to bottom.

A color TV screen differs from a black-and-white screen in three ways:

  1. There are three electron beams that move simultaneously across the screen. They are named the red, green and blue beams.
  2. The screen is not coated with a single sheet of phosphor as in a black and white TV. Instead the screen is coated with red, green and blue phosphors arranged in dots or stripes. If you turn on your TV or computer monitor and look closely at the screen with a magnifying glass, you will be able to see the dots.
  3. On the inside of the tube, very close to the phosphor coating, there is a thin metal screen called a shadow mask. This mask is perforated with very small holes that are aligned with the phosphor dots on the screen.

When a color TV needs to create a red dot, it fires the red beam at the red phosphor. Similarly for green and blue dots. To create a white dot, red, green and blue beams are fired simultaneously - the three colors mix together to create white. To create a black dot, all three beams are turned off as they scan past the dot. All other colors on a TV screen are combinations of red, green and blue.

The existing TV standards, such as PAL, SECAM, NTFS use an interlacing technique when painting the screen. In this technique, the screen is painted 60 times per second but only half the lines are painted per frame. The beam paints every other line as it moves down the screen, for example every odd-numbered line. Then the next time it moves down the screen it paints the even-numbered lines, alternating back and forth between even-numbered and odd-numbered lines on each pass. The entire screen, in two passes, is painted 30 times every second creating interlaced fields.

The inertia of human eyesight together with the use of long-lighting materials for the television tube allow not to notice the drawbacks of the interlacing scanning. Only in case the minor details of the image are considered and especially text we can notice some "flickering effect".

The alternative to interlacing is called progressive scanning, which paints every line on the screen 60 times a second. The today's computer monitors use progressive scanning only because it significantly reduces flickering.

It is possible to display on the monitor with progressive scanning the frames of the recorded video stream or the image from the TV-tuner with interlacing scanning techniques. In this case you will have to put together all even and odd frames from both interlaced fields, one by one (Weave de-interlacing method). However, the refresh rate will get almost twice as low and some very unpleasant interlacing effect may appear:

It appears because when the moving object is filmed for the first interlaced field, it is situated in one place, however, by the time another field is filmed, the object is turns out to have moved a bit, so that its location is different. This way, when we put together the interlaced fields, which stand 1/50 of a second from one another, we get this sad picture.

Another way of displaying the interlaced fields on the monitor suggests duplicating the lines in each of the fields. In this case the refresh rate will remain the same as by the initial signal, the interlacing effect will disappear, however, the vertical clarity will get twice as bad:

Of course, the developers of those chips, which are responsible for signal decoding and digitizing do know about these problems that is why the today's chips process the image in a more complicated way, so that it hardly differs from the image displayed on the TV-screen, which should be close to the image below for our case:

Philips SAA7108 installed onto NVIDIA Personal Cinema by VisionTek is capable of displaying moving objects with great image quality.

Read more on television techniques here.

Video Capturing

InterVideo WinDVR allows capturing isolated frames and video movies and storing them on the system HDD.

Video capturing can be made from the WinDVR window and takes almost no time. The captured frames are stored in a separate window, where you can look them through and then save those you liked most.

The frames are stored as 24bit BMP-files. The movies are stored as MPEG1 or MPEG2 files. To record this video movie, one can use standard schemes or those he (or she) created themselves.

Creating your own record profile:

Adjusting the Record Profile properties:

Setting the Video compression parameters:

Setting the audio parameters:

We tried capturing video on a very powerful high-performance system, so there wasn't any difficulty with that. The only inconvenience is that you have to keep an eye on the available disk space. But even those of you who would like to record with the maximum quality and who care about the file size, will be able to adjust the compression and capturing parameters up to your needs.

Additional Functions, Teletext

Among the additional features, we got mostly attracted by the electronic schedule. It allows to preset the tuner so that it could turn on any time, once in a while or regularly. For example, you can make it record some particular football match and daily news programs, etc.

As far as we understood, the decoding of such digital extras added to the video signal as teletext or closed caption aren't yet supported by NVIDIA Personal Cinema, although Philips SAA7108 can recognize this kind of data, according to the official Philips site.

Conclusion

NVIDIA Personal Cinema deserves being called a successful product, especially since it's the company's first experience in the TV-tuner field. This solution features advantages and drawbacks of a typical TV-tuner, however, its unusual implementation also adds some unique features.

For example, the ability of this solution to transfer the image from the TV-tuner via the control cable in analog format eliminates the risk of hardware conflicts with another computer component parts, unlike the case of PCI TV-tuner used. However, on the other hand, it requires the VIVO (tuner powering and control) support from the graphics card. That is why the package includes a graphics card as well.

Miniature size on the one hand is a great advantage, but on the other - a drawback: connected to different devices with many cables this small and light box is always about to fall from the required position.

The remote control unit is a good thing, however, we are not sure that it will work if somebody decides to hide the tuner with all those cables.

Highs:

  • Stylish look;
  • Great functionality;
  • Video-In and Video-Out;
  • Remote control unit;
  • High quality of image digitizing;
  • Excellent software bundle.

Lows:

  • Low sensitivity of the RF-module;
  • No manual channel frequency tuning;
  • Incorrect work of timeshifting function;
  • No support for teletex and closed caption;
  • Too light weight and miniature size;
  • No FM-tuner.
 
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