Most popular high definition HD video formats:
1) 720p – 1280 × 720 pixels (dots), progressive scan (progressive scan, all lines in each frame are displayed sequentially), 16: 9 aspect ratio, frequency – 24, 25, 30, 50 or 60 frames per second ; 2) 1080i – 1920 × 1080 pixels, interlaced (each frame is divided into two half frames, consisting of lines selected with a line separating, 2 times the frame rate compared to progressive), 16: 9 aspect ratio , frequency – 50 or 60 fields per second; 3) 1080p – 1920 × 1080 pixels, progressive scan, 16: 9 aspect ratio, frequency – 24, 25 or 30 frames per second.
What is the difference between 1080i and 1080p?
Each of these video formats uses a different way to convert a series of still images into movies. In interlaced scanning (“i” symbol), a still image or “frame” is reproduced by scanning 2 sets of alternating lines or “fields” (half frames). With progressive scan (“p” symbol), a frame is created in a single pass (scan). That is, if the image scan in both video formats (“i” and “p”) is performed at the same speed, then an equal number of runs per second occurs, then the advantage of progressive scan (“p” ) becomes obvious (image quality is better), as the entire image (frame) is scanned and not half the image (field). Within this progressive scan (“Conclusion: 1080i and 1080p video formats look better in different conditions. 1080i video format is designed to reproduce fine image details with little movement or in frames and still images. video is much better suited for “spatial resolution.” 1080i video format works fine as long as there is no frame movement. When objects begin to move, the path of movement between alternating fields (half frames) begins to change. called “motion artifacts”; visible image noise or video distortion that resembles an irregular pattern. 1080i video quality is considered outdated. 1080p video quality has the advantage of motion. Does not introduce visible distortion into the image regardless the speed of moving objects, so it has the best “temporal resolution.” Still images will not look very clear when I keep the image frozen because there are far fewer dots and lines in 1080p video than in 1080i. Long-distance transmission of the HDTV video signal (satellite TV – S2, cable TV) is generally done using compression methods to reduce the bandwidth requirements for data transmission (from 1.485 Gbps to 8-25 Mbps ), while the video quality is still good. To encode a video signal, the best video formats MPEG-2, MPEG-4, H.264 or AVC (Video Compression Standards (codecs), which are designed to achieve a high compression ratio of the video signal maintaining high quality). Transmission of the HDTV video signal over a short distance (from the user’s tuner (receiver) to the monitor (TV)) is done in its original form (uncompressed) via HDMI and DVI-D digital cables. The use of digital interfaces (cables) completely avoids video compression and conversion and preserves the best image. Digital video quality is a measure of signal-to-noise ratio. What is the best video and movie quality, and which can be downloaded from the Internet? Well, first of all, it must be said that the main requirement of Internet formats is compactness. Clearly, the DVD or HDTV format will not work. But almost any video recorded with a mobile phone or digital camera meets the requirements of the Internet. And the question arises: what is the most optimal and best video quality with maximum compression for the convenience of downloading from the Internet, and what are the designations of movie formats? Many Internet users confuse better quality HDTV movies with the HDTV-Rip video extraction method. HDTV-Rip is a video copy of a high definition video (movies) streaming source: HDTV. This can be done using a variety of codecs and compression methods. As a result, HDTV-Rip movies may not be of the highest HD quality. Rip video streams from an HDTV channel may come with the channel’s logo. Also, don’t confuse HD video with HDTV high definition video.
