Tag Archives: video format

720i

Feb 23rd, 2010by dvdxplayer 5,309 views |Comments Off

One of the resolution specs used in the HDTV. 720i stands for resolution of 1280×720 pixels and the magic little ‘i’ means that the video is in interlaced format. Other common HDTV resolutions are 1080i and 720p.

The term in itself however, is erroneous and is usually a typo. The user of the term is almost certainly talking about 720p as there is no broadcast standard that allows for 720 interlaced lines in a video at any frame rate, including PAL or NTSC.

The definition of 1080p

Feb 20th, 2010by dvdxplayer 3,106 views |1 Comments

1080p refers to a progressive HDTV signal with 1080 horizontal lines and an Aspect Ratio of 16:9 (1.78:1). All major HDTV broadcasting standards include a 1080i format which has a resolution of 1920×1080, but the progressive HDTV broadcast standards in place right now only allow a resolution of 1280×720 (720p). Currently the only applications using 1080p signals are Blu-ray and HD DVD. Read More »

what’s 1080i?

Feb 19th, 2010by dvdxplayer 3,418 views |1 Comments

1080i refers to an interlaced HDTV signal with 1080 horizontal lines and an Aspect ratio of 16:9 (1.78:1). All major HDTV broadcasting standards include a 1080i format which has a Resolution of 1920×1080, however there are other formats, including HDV and AVCHD for camcorders, which utilize 1080i images with a resolution of 1440×1080. Confusing matters even further, a 4:3 (1.33:1) image broadcast in 1080i (1920×1080) uses the center 1440 Pixels for the image, with 240 pixel wide pillarbox borders on each side.

For HDTVs themselves 1080i can also have different meanings. While you might expect a 1080i HDTV to have a resolution of 1920×1080, this isn’t always the case. For many flat panel 1080i HDTVs the actual Native Resolution is 1366×768. While these TVs accept 1080i input signals (as do all HDTVs) they must scale them down to their native resolution, resulting in somewhat lower picture quality.

Advantages
The obvious advantage to 1080i resolution is that it uses the highest (standard) resolution available for TV signals and consumer electronics equipment. It can also be better for older (analog) interlaced video, which was a standard format to use for TV broadcasting (and video tape) for decades.

Disadvantages
Although there are HDTV broadcasts in 1080i, many channels broadcast in 720p. These broadcasts must be upscaled by any 1080i HDTV. This is particularly true of sports channels. Additionally, regardless of the capabilities of the display, the video encoding currently used for HD video allow a maximum of 30fps for 1080i, while 720p may be encoded at 60fps.

About AVI – which stands for Audio Video Interleave

Feb 08th, 2010by dvdxplayer 13,363 views |2 Comments

A Container format used by Microsoft’s Video for Windows multimedia framework. Since it was developed for Windows 3.1 in 1992 it lacks some features found in newer containers like MPEG or MP4, but is still widely used by consumers and even supported by some standalone DVD players. Although still supported in Windows, and suitable for certain formats like DV, it’s not a good general purpose container, and even Microsoft uses other containers for their own video formats.

About FLV (Flash Video)

Feb 03rd, 2010by dvdxplayer 1,669 views |2 Comments

FLV (Flash Video) is a proprietary file format used to deliver video over the Internet using Adobe Flash Player (formerly known as Macromedia Flash Player) version 6, 7, 8, or 9. FLV content may also be embedded within SWF files. Notable users of the FLV format include YouTube, Google Video, Reuters.com, Yahoo! Video and MySpace.

About H.264

Feb 02nd, 2010by dvdxplayer 1,510 views |Comments Off

H.264 is known as MPEG4 AVC.  The standard is expected to offer up to twice the compression of the current MPEG4 ASP (Advanced Simple Profile), in addition to improvements in perceptual quality. The H.264 standard can provide DVD-quality video at under 1 Mbps, and is considered promising for full-motion video over Topwireless, satellite, and ADSL Internet connections.

What’s CBR/ABR/VBR?

Jan 13th, 2010by dvdxplayer 1,353 views |Comments Off

CBR means that the stream’s bitrate is constant and never changes.
VBR means that the stream’s bitrate is variable, and changes in according to the amount of information that needed to be encoded.
ABR has a variable bitrate for each frame, but its average bitrate is a constant. Read More »

What is Divx?

Dec 25th, 2009by dvdxplayer 3,118 views |Comments Off

Depending on whom you ask, Divx (Digital Video Express, first known as ZoomTV) was either an insidious evil scheme for greedy studios to control what you see in your own living room or an innovative approach to video rental that would have offered cheap discs you could get almost anywhere and keep for later viewings. Read More »