- What is Dolby Pro Logic®?
Dolby Pro Logic is a matrix decoder that decodes the four channels of surround sound that have been encoded onto the stereo soundtracks of Dolby Surround program material such as VHS movies and TV shows. Dolby Surround is a matrix encoding process that in essence "folds" Left, Center, Right, and Surround channels onto stereo soundtracks. A Pro Logic decoder "unfolds" the four channels on playback (without a Pro Logic decoder, the encoded program plays in regular stereo).
NVDVD 2.0 Standard supports Dolby Pro Logic.
For more information on Dolby, please visit www.dolby.com
- What is Dolby Pro Logic® II?
Dolby Pro Logic II is an advanced matrix decoder that derives five-channel surround (Left, Center, Right, Left Surround, and Right Surround) from any stereo program material, whether or not it has been specifically Dolby Surround encoded. On encoded material such as movie soundtracks, the sound is more like Dolby® Digital 5.1 (see below), while on unencoded stereo material such as music CDs the effect is a wider, more involving soundfield. Among other improvements over Pro Logic, Pro Logic II provides two full-range surround channels, as opposed to Pro Logic's single, limited-bandwidth surround channel.
NVDVD 2.0 Standard supports Dolby Pro Logic II.
- What is Dolby Digital 5.1?
Dolby Digital 5.1 is a method of transmitting and storing 5.1-channel soundtracks via digital media such as DVD, digital cable, digital broadcast TV (DTV), and satellite transmissions. Unlike the Dolby Surround encode/Pro Logic decode process, which sacrifices channel separation to get surround onto any stereo soundtrack, Dolby Digital is a discrete system that keeps the multiple channels fully separated throughout the encoding and decoding processes. Dolby Digital 5.1 is the industry standard for encoding surround sound DVD movies.
NVDVD 2.0 Standard supports Dolby Digital 5.1.
- What does 5.1 mean?
Multi-channel 5.1 encoding means having full-range Left, Center, Right, Left Surround, Right Surround channels, and low-frequency (".1" - those bass rumbles and booms you feel as well as hear in a well-equipped cinema). Dolby Digital and DTS® are both capable of 5.1 encoding and decoding.
- What is DTS?
DTS is a competing encoding standard to Dolby Digital. DTS supports multi-channel 5.1 encoding.
NVDVD 2.0 does not currently support DTS decoding. However, NVDVD 2.0 supports outputting DTS encoded audio through the S/PDIF connector for external decoding (compatible hardware is required).
For more information on DTS, please visit www.dtsonline.com
- What is S/PDIF?
S/PDIF (Sony/Philips Digital Interface) is a standard audio transfer file format. S/PDIF allows the transfer of audio from one file to another without the conversion to and from an analog format, which could degrade the signal quality.
NVDVD 2.0 supports outputting encoded audio via a PC's S/PDIF connector for external decoding on support devices.
- What is dynamic range control?
Dynamic range control enables boosting soft sounds and attenuating loud sounds, valuable when using headphones or late night listening.
- What is a VCD?
VCD stands for "Video Compact Disc." It is based upon the CD format and contains moving pictures and sound. A VCD has the capacity to hold up to 74/80 minutes—on 650MB/700MB CDs—of full-motion video along with stereo sound. VCDs use a compression standard called MPEG to store the video and audio. A VCD can be played on almost all standalone DVD Players and of course on all computers with a DVD-ROM or CD-ROM drive with the help of a software based player like NVDVD 2.0.
- What is a SVCD?
SVCD stands for "Super VideoCD". A SVCD is very similar to a VCD; it has the capacity to hold about 35-60 minutes on 650MB/700MB CDs with very good quality full-motion video along with up to 2 stereo audio tracks and 4 selectable subtitles. A SVCD can be played on many standalone DVD Players and on all computers with a DVD-ROM or CD-ROM drive with the help of a software based player like NVDVD 2.0.
- What are the differences between a VCD and a SVCD?
The quality of a very good VCD is about the same as a VHS tape, except VCD is usually a bit more blurry. An SVCD has sharper picture quality than a VCD because of the higher resolution video stored on the disc.
For more information on VCD and SVCD, please visit www.vcdhelp.com
- What is DivX?
DivX is a proprietary video encoding format. Content is available on the internet that makes use of this format. NVDVD 2.0 can play DivX content if the proper DivX decoders have been installed on the system.
For more information on DivX and to download the decoders, please visit www.divx.com
- What is interlaced content?
Interlaced content displays a video image as two separate fields. The first field displays every other line of the image and the second field is displayed at a slightly later time complete the image. This matches the way conventional televisions work.
DVDs created from content that was originally viewed on television will likely be interlaced, such as music videos or concerts. VCRs and many camcorders record in an interlaced format since the video is intended to be watched at a later time on a TV.
- What is progressive content?
Progressive content displays each video image as a single frame. In other words, every line of the image is displayed at once. This matches the way film is displayed.
DVDs created from film content will likely be progressive, since each frame of the movie is digitized and encoded into a single frame.
- What is the difference between video and film formats?
Video content is interlaced, and typically 30 frames (meaning 60 fields) per second, while film content is progressive, typically 24 frames per second. The "Video Format" section of NVDVD Video property page indicates if the current content is film or video.
- What is the aspect ratio?
The aspect ratio specifies the ratio between the width and height of a display that is required to not make the final image look stretched in any direction. Typical computer display resolutions such as 1024x768 have an aspect ratio of 4x3. Televisions also have an aspect ratio close to 4x3.
- What is the difference between full frame and widescreen?
Full frame refers to content that is authored to be played on displays with a 4x3 aspect ratio, such as conventional televisions and computer screens. Widescreen refers to content that is authored to be played on displays with a 16x9 aspect ratio, such as widescreen televisions.
If widescreen content is viewed on a 4x3 display, then the top and bottom of the image is padded with black space.
- What is De-interlacing?
De-interlacing is the process of taking two interlaced fields and generating a single frame to be viewed on a progressive display, such as a computer monitor.
- What is bob?
Bob is a de-interlacing algorithm that displays each field of an interlaced image separately. The missing lines for each field are interpolated from the lines that are present.
This is the de-interlace mode used when "display fields separately" is set in the NVDVD Video property page.
- What is weave?
Weave is a de-interlacing algorithm that simply weaves the two interlaced fields together to generate a frame. This works well if the image is still, but the slight difference in time between the fields causes a moving object or panning scene to contain edges that appear feathered. (add picture of weave feathering)
This is the de-interlace mode used when "combine fields" is set in the NVDVD Video property page. This mode does not hinder video playback performance, but it does not produce the best visual results.
Weave can be improved visually by blending the fields together, where each line of the image is created from multiple lines above and below it. This does, however, have the effect of blurring the image slightly.
- What is adaptive de-interlacing?
Adaptive de-interlacing is a more advanced algorithm that looks at a sequence of frames to determine if an area is still or in motion. For pixels that are still, the fields are simply combined without a blend. If in motion, the fields are blended together. This produces the best visual results but is more computationally intensive.
NVDVD is able to perform adaptive de-interlacing in hardware, which keeps the CPU from performing this intensive task. This maintains smooth DVD playback even when de-interlacing.
- What is hardware acceleration?
It is common for recent graphics chips to support some level of the MPEG-2 decode in hardware. This offloads the CPU from performing the same decode tasks. For less CPU usage, make sure that the "Hardware acceleration" setting on the NVDVD Video property page is enabled.
When hardware acceleration is enabled, the "Decoder Format" section of the NVDVD Video property page will indicate the DXVA mode that is currently being used. If hardware acceleration is disabled or not available on the system, the same section will indicate a software mode such as YUY2.
- What is DXVA?
DXVA stands for DirectX Video Acceleration, a standard defined by Microsoft to allow video decoders to access the video acceleration capabilities of the graphics hardware in the system. All display drivers that pass Microsoft's WHQL testing support this standard.
- What is the difference between hardware overlay and video mixing?
Hardware overlay uses special, dedicated video hardware to display a video image, such as a DVD. The Video Mixing Renderer (VMR), however, uses the 3D graphics hardware to render the video to the screen.
Hardware overlay is a limited resource, typically allowing use on only a single display. If running on multiple displays, then VMR should be used to avoid this limitation.