Some recordings, such as in HDV video camcorders, and many HD TV signals are stored or broadcast at 1440 x 1080i. This is another bit of trickery used to reduce the amount of data needed to record or broadcast the footage. The pixels in the video are oblong (non-square). The pixel aspect ratio is 1.33:1. Essentially this means the pixels are stretched horizontally to fill a 1920 x 1080 frame during playback. This is hardly noticeable to the average viewer. You may also see 960 x 720 pixel video from some cameras. Again these employ non-square pixels to generate a 720p image.
Nearly all modern video cameras (PAL UK models) can do 1080p. Some but not all will do 1080i as well. In essence the choice of camera depends largely on how much you want to spend and what type of activity you want to film.
100 Fps 720p Vs 1080i
iPhone 4 records 16:9 aspect ratio 1280x720p video via the main camera at a nominal 30 frames per second. However, Apple devices tend to record at an irregular frame rate which causes Adobe Premiere to choke on the files.
The HM100 boasts three newly designed -inch progressive CCDs that capture both 1080p and 720p video at 24 and 30 frames per second (fps) and at 60 fps in 720p or 1080i. These HD formats can be recorded at multiple bit rates from 19-35 megabits per second (Mbps). The camera records to class 6 and above SDHC cards and features two card slots. The maximum capacity SDHC card currently available is 32 GB, which can hold upwards of four hours of 24p HD each, or eight hours of continuous recording when used in both card slots.
1080i (also known as Full HD or BT.709) is a combination of frame resolution and scan type. 1080i is used in high-definition television (HDTV) and high-definition video. The number "1080" refers to the number of horizontal lines on the screen. The "i" is an abbreviation for "interlaced"; this indicates that only the even lines, then the odd lines of each frame (each image called a video field) are drawn alternately, so that only half the number of actual image frames are used to produce video. A related display resolution is 1080p, which also has 1080 lines of resolution; the "p" refers to progressive scan, which indicates that the lines of resolution for each frame are "drawn" on the screen in sequence.
Within the designation "1080i", the i stands for interlaced scan. A frame of 1080i video consists of two sequential fields of 1920 horizontal and 540 vertical pixels. The first field consists of all even-numbered TV lines and the second all odd numbered lines. Consequently, the horizontal lines of pixels in each field are captured and displayed with a one-line vertical gap between them, so the lines of the next field can be interlaced between them, resulting in 1080 total lines.[1]
1080i differs from 1080p, where the p stands for progressive scan, where all lines in a frame are captured at the same time. In native or pure 1080i, the two fields of a frame correspond to different instants (points in time), so motion portrayal is good (50 or 60 motion phases/second). This is true for interlaced video in general and can be easily observed in still images taken of fast motion scenes. However, when 1080p material is captured at 25 or 30 frames/second, it is converted to 1080i at 50 or 60 fields/second, respectively, for processing or broadcasting. In this situation both fields in a frame do correspond to the same instant. The field-to-instant relation is somewhat more complex for the case of 1080p at 24 frames/second converted to 1080i at 60 fields/second; see telecine.
The field rate of 1080i is typically 60 Hz (i.e., 60 fields per second) for countries that use or used System M (NTSC and Brazilian PAL-M) as analog television system with 60 fields/sec (such as United States, Canada, Mexico, Japan, South Korea, Taiwan and Philippines), or 50 Hz for regions that use or used 625-lines (PAL or SECAM) television system with 50 fields/sec (such as most of Europe, most of Africa, China, India, Australia, New Zealand, Middle East, and others). Both field rates can be carried by major digital television broadcast formats such as ATSC, DVB, and ISDB-T International. The frame rate can be implied by the context, while the field rate is generally specified after the letter i, such as "1080i60". In this case 1080i60 refers to 60 fields per second. The European Broadcasting Union (EBU) prefers to use the resolution and frame rate (not field rate) separated by a slash, as in 1080i/30 and 1080i/25, likewise 480i/30 and 576i/25.[2] Resolutions of 1080i60 or 1080i50 often refers to 1080i/30 or 1080i/25 in EBU notation.
Worldwide, most HD channels on satellite and cable broadcast in 1080i. In the United States, 1080i is the preferred format for most broadcasters, with Warner Bros. Discovery, Paramount Global, and Comcast owned networks broadcasting in the format, along with most smaller broadcasters. Only Fox- and Disney-owned television networks, along with MLB Network and a few other cable networks, use 720p as the preferred format for their networks; A+E Networks channels converted from 720p to 1080i sometime in 2013 due to acquired networks already transmitting in the 1080i format. Many ABC affiliates owned by Hearst Television and former Belo Corporation stations owned by TEGNA, along with some individual affiliates of those three networks, air their signals in 1080i and upscale network programming for master control and transmission purposes, as most syndicated programming and advertising is produced and distributed in 1080i/p, removing a downscaling step to 720p. This also allows local newscasts on these ABC affiliates to be produced in the higher resolution (especially for weather forecasting presentation purposes for map clarity) to match the picture quality of their 1080i competitors.
Some cameras and broadcast systems that use 1080 vertical lines per frame do not actually use the full 1920 pixels of a nominal 1080i picture for image capture and encoding. Common subsampling ratios include 3/4 (resulting in 1440x1080i frame resolution) and 1/2 (resulting in 960x1080i frame resolution). Where used, the lower horizontal resolution is scaled to capture or display a full-sized picture. Using half horizontal resolution and only one field of each frame (possibly with added anti-alias filtering or progressive capture) results in the format known as qHD, which has frame resolution 960x540 and 30 or 25 frames per second. Due to the chosen 16x16 pixel size for a compressed video packet known as a macroblock as used in ITU H.261 to H.264 video standards, a 1080-line video must be encoded as 1088 lines and cropped to 1080 by the de-compressor. The 720-line video format divides perfectly by 16 and therefore does not require any lines to be wasted.
Today, televisions throughout the world use the standard window sizes known as High Definition or HD. There are two different sizes recognized by that standard usually displayed as 1080p/1080i or 720p/720i. The window size for those are 1920 pixels wide x 1080 pixels high, or 1280 pixels wide x 720 pixels high, respectively. A pixel is the smallest dot on a screen that is made up of a red, green and blue light source.
Most videos uploaded to the Internet usually follow these same television standards. 720p was a transitional window size as we moved away from the old television standard from the 1950s, known as Standard Definition or SD, and is not used as often today.
4:2:2 10-bit (When [Rec Quality] is set to [4:2:2 10bit] or when [Rec Quality] is set to [4K/60p]/[4K/50p] and [4K/60p Bit Mode]/[4K/50p Bit Mode] is set to [4:2:2 10bit]. When [4K/60p]/[4K/50p] mode is selected in [Rec Quality], it is not possible to record motion picture or still picture on the SD memory card in the camera unit.)/4:2:2 8bit (When [Rec Quality] is set to [4:2:0 8bit], except for [4K 60p]/[4K/50p])/4:2:0 8bit (When [Rec Quality] is set to [4K/60p]/[4K/50p] and [4K/60p Bit Mode]/[4K/50p Bit Mode] is set to [4:2:0 8bit].)/Auto / 4K/30p/25p / 1080p / 1080i / OFF/Information display ON/OFF (selectable)/Automatic down-conversion/HLG View Assist (HDMI) AUTO / MODE1 / MODE2 / OFF (selectable)*7
With the introduction of the high-definition (HD) resolutions such as 720p and 1080p, the aspect ratio became 16:9 also named widescreen, and was established as the new worldwide standard by TV industries and laptop screen manufacturers.
Today's broadcast video common denominator is SDI, either SD or HD. SMPTE 294M specifies SDI at a 29.97 frame rate and a 59.94 field rate for SD and 1080i or p. HDTV in the 1080i format, as fed to and rebroadcast by most NBC, CBS and PBS affiliates, is at 59.94 fields per second. The 720p format, as specified by SMPTE 296M and used by ABC, FOX and ESPN, has no fields. It delivers 59.94 progressive frames per second. Both 1080i and 720p mathematically match downconverted SD video.
As you allude to, you should really have figured out how to get the 23.976 capture to work in the 23.976 project in order to have a perfect frame per frame conform of the project in HD. Also, there is no such thing as 1080i/23.976 or 24 since these are progressive formats. At worst they are 1080pSf/23.976 (segmented frame). When capturing a down convert from 1080p/23.976 as NTSC, you need to make sure the menus are correct for create 2:3 pulldown on timecodes that end in 0 and 5. Once that is done, when in Adrenaline, go to he Film/24p settings and set PULLDOWN to 2:3:2:3 (NORMAL) and set the CADENCE to 00:00:00:00 to A. This will allow for correct capture of HD down convert as NTSC in a 23.976 project. This is exactly the same process used by Steven Soderbergh on his film "Bubble" shot in 1080p.23.976, captured and edited on Avid Xpress Pro and finished on DS Nitris. But seeing as you chose to move forward as 29.97 NTSC interlace with pulldown, all of your edits will have a broken cadence in them forcing you do to a field removal to 1080p/23.976 via a Teranex or other type process. Adding cost and lowering the quality since edit points will need to be recreated from 1/2 frames reducing the overall vertical resolution by 50%. 2ff7e9595c
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