As mentioned yesterday in the TechDigs.net article HDTV Shopping HELLp! An HDTV Technology Overview, the HQV Benchmark DVD is a good tool for evaluating the processing quality of a video device. Today, we do a brief review of the HQV DVD, including the various performance tests. We also provide an Excel and OpenOffice template for storing your HQV benchmarks. We like this utility and think everyone evaluating video devices should own a copy.

Read more for details.

Color Bar / Vertical Detail

With the use of a static image, the first test evaluates how well your video processor identifies motion. You've probably seen single pixel lines vibrate on screen. This test demonstrates the ability of a display to manage that annoyance. Additionally, you can evaluate how smooth color graduations are.

HQV Color Bars

Jaggies

Jaggies are the stairstep effects that can occur with interlaced moving objects. HQV has three jaggies tests for evaluating your deinterlacer's ability to recognize motion.

HQV Jaggie Pattern

HQV Flag Jaggies

Two use animations to illustrate the problem; the third is an American flag blowing in the wind. These tests do a good job of showing the difference between good and bad delinterlacers.

Detail Enhancement

The next test evaluates the ability of the video processor to effectively and accurately sharpen video without the halo effect that can often result.

HQV Detail Enhancement

Noise Reduction

HQV Noise

Image noise can occur for a number of reasons including image sensor and film noise, scanning and duplication, and compression. It occurs with both digital and analog video. The ability of a video processor to reduce noise without losing image detail can measurably enhance images. Often, however, so much detail is lost that it's not worth using the digital noise reduction capability. HQV provides two tests, a static noise reduction test and a motion adaptive noise reduction test. These tests help you decide how well the DNR works and whether it's worth using.

Film Detail and Cadence

HQV 3:2 Film Detail

Motion pictures are produced at a rate of 24 progressive frames per second. Broadcast TV & DVDs are nearly 30 (29.97 to be exact) frames per second. Therefore, when motion pictures are converted for use in TV or DVD, they must be converted from 24 frames per second to 29.97 frames per second. To accomplish this, a technique known as 3:2 pull-down is used. In 3:2 pull-down, first the 24 frames per second are slowed down to 23.976 frames per second which gives a 4/5 ratio between 23.976 and 29.97. Then, 4 frames are stretched into 5 by repeating a film frame after every fifth field of video. Bottom line, this process can cause odd artifacts that need to be effectively dealt with to make the video appear smooth. This requires video processors capable of detecting and removing the extra frame. 3:2 pulldown, especially when displaying titles, can present a real challenge for video processors.

In addition to the very common 3:2 film cadence, there are other techniques including 2:2:2:4, 2:3:3:2, 3:2:3:2:2, 5:5, 6:4, 8:7. Overall, HQV has eleven tests dealing with film cadence and a video processor's ability to effectively deal with each.

Scoring

For each test area, HQV provides a scoring guide and score sheet that can total as high as 130. As you go through each test, it's important to be both consistent and objective. No device will score perfectly. The key is to end up with a meaningful relative score.

Evaluating HDTVs vs. DVD Players

 

To evaluate an HDTV or monitor you need to use a DVD player. It's important to configure the settings for both the display and the DVD player correctly depending on which you are testing.

Evaluating DVD Players

When evaluating DVD players, be sure to turn off any and all digital noise reduction, de-interlacing, film mode, color enhancement, etc., available on the display. You don't want a display video processor to skew the results of your DVD evaluation. If possible, also test all DVD players using the same display.

Evaluating HDTVs and Monitors

When evaluating display devices, be sure your DVD player is in interlaced mode (as opposed to progressive) and that any digital noise reduction, film mode, etc., is turned off on the DVD player before you begin the tests. If possible, test all displays using the same DVD player.

Evaluating Video Processors

When evaluating video processors and scalers, be sure your DVD player is in interlaced mode (as opposed to progressive) and that any digital noise reduction, film mode, etc., is turned off on the DVD player before you begin the tests. Also, be sure to turn off any and all digital noise reduction, de-interlacing, film mode, color enhancement, etc., available on the display. If possible, also test all video processors/scalers using using the same display and DVD players.

Objective vs. Real World Subjective

Clearly, the goal of the HQV Benchmark is to be an objective tool. While it contains subjective elements, if you follow their guide correctly you can end up with a repeatable objective score.

When evaluating devices, it's also important to add real-world subjective tools to the mix. DVD movies are a good way to do that. Examples of movies that reviewers often use include: Goodfellas, Gladiator and The Fifth Element. Make sure that you are using anamorphic (enhanced for 16:9) versions of these DVDs.

Pros

• Excellent, objective evaluation tool
• Inexpensive
• Easy to use
• Consistent results
• Works on every DVD player, TV and computer we tested

Cons

• Assuring that you turn off processing on devices not being evaluated is crucial, and yet not always straight forward. This is not a function or fault of HQV, but it is imperative for accurate evaluations.
• No tech support email or phone number. At $30.00, we don't blame them. However, just be aware before you purchase HQV.

Conclusion

If you are in the market for a new DVD player, HDTV, or video processor/scaler, then HQV Benchmark is a must-have. At $30, it's a great objective measure as well as easy to use.

TechDigs.net Tools

To help make it even easier, TechDigs.net is providing a spreadsheet template that you can use to keep the scores from your HQV Benchmarks.

• TechDigs.net Microsoft Excel Template: Excel File, Zip File
• TechDigs.net OpenOffice Spreadsheet Template: OpenOffice File, Zip File
  (OpenOffice is free for Windows, Mac, Unix: openoffice.org)

You can order the HQV Benchmark at www.hqv.com.

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