Basic comparison: AnalogTV, SDTV, EDTV and HDTV

There was a time when we only had one option when buying a television, that is, a conventional analog television or a CRT television. But today we have so many options. First, we have our conventional CRT (cathode ray tube) television. Along with this, we have new options like HDTV, EDTV, and SDTV. But what is the best for you? What are the main differences in them? Let’s try to understand the basics of each of them.

Conventional analog TV:

First of all, let’s talk about our conventional CRT television. CRT TV video displays contain 525 lines of resolution, although only 480 lines are displayed. These lines are painted using the “interlacing” technique. In this technique, you first paint all the odd lines from 1 to 479. Immediately afterwards you paint all the even lines from 2 to 480. This standard analog TV format represents as 525 interlaced or 525i, this is also represented by the term “480i”. The aspect ratio of the screen is 4: 3. This TV has a built-in NTSC tuner, so by default it cannot tune in to digital TV broadcasting.

Analog TV:

With NTSC, broadcasting has been dominating for the past 50 years. But it is time for DTV (digital TV) to gradually replace Analogue. Digital television is a new type of broadcast technology that offers television with movie-quality pictures and Dolby digital surround sound, along with a variety of other enhancements. This digital TV works with ATSC transmission instead of NTSC. There are currently three types of digital broadcast signal: SDTV, EDTV, and HDTV. The aspect ratio for DTV is 16: 9.


Like analog TV, SDTV also 480i. Here’s the advantage compared to Analog: SDTV can receive digital broadcast signals.


So far, TVs with 480i resolution have performed well. This is because TV sizes are limited to 19 or 20 inches. But the 480i resolution limitation arose when applying the same technology on a large screen. Interlacing techniques do not work for larger screens. Visible scan lines and irregularities are annoying. The best solution is to avoid interlacing. Initially, interlacing was invented to save transmission bandwidth. But in today’s technology, transmission at a much higher speed is possible. So, there is no need to intertwine. It is possible to paint the lines sequentially from 1, 2, 3 …. to 480, this is called “” progressive scan. “With this technology using the same 480 resolution lines we can get a better video quality, jaggies can be fully This 480-line progressive scan technique is commonly known as 480p.This concept in the consumer market is known as Enhanced Definition Television or EDTV.

Both SDTV and EDTV also receive 16 by 9 broadcasts along with the 4 by 3 aspect ratio.


Even though we have the SDTV and EDTV digital broadcasting system, the most attention is drawn to HDTV. The main advantage here is a greater number of scan lines on the screen. HDTV comes in three flavors 720p, 1080i and the latest 1080p. As the name says, the first resolution shows 720 lines progressively and the second one shows 1,080 interlaced lines. If we compare these two, we can say that both are good. In general, 720p is more suitable for fast actions, as it uses progressive frames; alternatively 1080i is very good for slow moving pictures (this is probably why most HDTV movie theaters can watch slow moving movies). 1080p, on the other hand, provides an image resolution of 1920 by 1080 pixels. This one provides the best visualization compared to others. This is because 1080p contains the maximum number of pixels compared to other varieties, in addition to 1080 lines of progressively scanned line which is considered better than interlaced.

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