Television Standards - Formats and Techniques

Television Standards - formats and techniques

In opposite to the common simplified representation of the NTSC standard in the world wide web this summary should provide an essentially correct overview of the different refresh rates of PAL and NTSC. At this point it is important to consider the transfer from film material to the standards of PAL and NTSC. Furthermore we have to mind the video format

MPEG-2, which is used for DVDs.

index | Worldwide TV Systems | DVD Region Codes | FAQ

1. FILM 5.2 MPEG-2, T_F_F/R_F_F Flags and FPS Flag

2.1 NTSC Video Time Code Counters

2.2 PAL 5.3 Drop Frame/Non Drop Frame

2.3 SECAM PAL-60

3.1 Interlacing 6. Digital Television

3.2 Interlaced 7.1 LDTV - SDTV - EDTV - HDTV

3.3 Progressive 7.2 ATSC

3.4 Deinterlacing 7.3 DVB (EBU, ETSI)

4.1 FILM-PAL-NTSC-Transfer 7.4 H.264/AVC

4.2 Telecine 7.5 ISDB (ARIB)

4.3 Inverse Telecine (IVTC) 7.6 Ultimate Comments

4.4 Overview 8. Examples

5.1 MPEG, Layer and Picturetypes 9. References

- Sequence, Group Of Pictures (GOP), DCT, Run-Level 10.

VLC,...

1. FILM

Motion picture films are shot in 24 fps (frames per second - full-images - progressive) usually on 35 mm film material. The film has a frame rate of 24 frames per second. However, in the cinema the film is not played with 24 Hz. With a rotary shutter which is installed between source of light and film strip the latter will be shined through either twice or thrice - depending on the projector. For us not noticing the movement of the film strip on the film reel the canvas has to become black for a very short time between the film frames.

At 24 black time intervals per second we would notice a clear flickering. With the double or triple refresh rate of 48 Hz or 72 Hz the human eye does not notice these black time intervals any longer. Hence, the cinema picture is noticed to be fluent and without any flickering. Hz = Hertz = 1/s (1/sec) - "Hz" means in our case "pictures per second".

We can call a frame rate of 24 fps (respective 48 Hz/72 Hz) the nominal cinema speed. Measuring the run time completely from the beginning to the end we will find out that the playing speed in the cinema usually varies from 24 fps. A motion picture film mostly is somewhat faster played whereby the frame rate can be located between 24 fps and 26 fps. 2.1 NTSC (National Television System Committee)

This format is used particularly in the USA, Canada, Mexico and Japan. NTSC altogether uses 525 scan lines, thereof approx. 485 are visible. The color subcarrier has a frequency of approx. 3.58 MHz in the case of analog NTSC. The common NTSC color subcarrier system is also called "NTSC M" or "NTSC 3.58". The refresh rate is 29.97 Hz or 29.97 fps respectively. This corresponds to 59.94 Hz

(interlaced - half-images) or 59.94 fields/s respectively which can be derived from the NTSC 2:3-Pulldown based on 23.976 fps of NTSC films. For detailed information related to the Pulldown refer to the "Transfer" section later in the text. The frame rate of 23.976 fps also conforms to the so-called NTSC-Film standard. The digital standard resolution is 720x480 pixel for DVDs (Digital Versatile Disc),

480x480 pixel for Super Video CDs (SVCD) and 352x240 pixel for Video CDs (VCD).

The much-seen "NTSC rounding up" of 59.94 Hz to 60 Hz as well as 29.97 Hz to 30 Hz can be very confusing if we take a more closer look to the TV formats. In former times the values 30 Hz/60 Hz were quite correct, but with the implementation of the color television the NTSC refresh rates were lowered from 60 Hz to 59.94 Hz and from 30 Hz to 29.97 Hz for preventing audio flutter during broadcast.

However, the NTSC refresh rate is not 59.95 Hz exactly but 60 Hz*1000/1001 = 59.9400599400599400... Hz ≈ 59.94 Hz. In the following sections of the text we will refer to the latter value of 59.94 Hz. The reason why the NTSC refresh rate was changed by implementation of color television is explained by Bob Myers in a detailed article.

• The original FCC standard:

525 scan lines interlaced with a 60 Hz refresh rate

525/2 = 262.5 lines/field

262.5 [lines/field]*60 Hz = 15750 lines/[field*s] := horizontal frequency (line rate)

(means that 15750 lines are transferred per field and per second)

15750 Hz*455/2 = 3.583125 MHz (hypothetical color subcarrier frequency)

• The NTSC standard of color television:

525 scan lines interlaced with a 60*1000/1001 Hz refresh rate

525/2 = 262.5 lines/field

262.5 [lines/field]*60*1000/1001 Hz = 15734.2657... lines/[field*s] horizontal frequency ≈ 15734 Hz

15734.2657... Hz*455/2 = 3.57954545... MHz (color subcarrier frequency)

For detailed information related to the Television Standards of all countries using NTSC refer to the worldwide comparison. 2.2 PAL (Phase Alternating Line)

This format is used particularly in Western Europe, Australia, New Zealand and in some areas of Asia. PAL uses altogether 625 scan

lines, thereof approx. 575 are visible. The color subcarrier has a frequency of approx. 4.43 MHz in the case of analog PAL

(complementary view). Special NTSC or PAL color subcarrier signals will not be transferred via connections like SCART (RGB) and YUV.

Such a signal is only transferred via connections like Composite Video, RCA, FBAS and Y/C or S-Video (S-VHS) respectively. The refresh

rate is 25 Hz or 25 fps respectively. This corresponds to 50 Hz (interlaced) or 50 fields/s respectively. The digital standard resolution is

720x576 pixel for DVDs, 480x576 pixel for SVCDs and 352x288 pixel for VCDs.

Related to NTSC, PAL has a shorter run time because of the higher amount of "fps" - PAL movies are (normally) not cut, but they are

"faster" (PAL Speedup). For detailed information related to the PAL Speedup refer to the "Transfer" section later in the text. For detailed

information related to the Television Standards of all countries using PAL refer to the worldwide comparison.

2.3 SECAM (Système en Couleur avec Mémoire)

Sometimes known as "Séquentiel Couleur avec Mémoire" - means "sequential color with memory". This format is used particularly in

France and still in most areas of Russia. Some eastern European states have reconverted from SECAM to PAL. SECAM has technical

similarities to PAL but it is not part of the DVD standards, for we can leave it out here. For detailed information related to the Television

Standards of all countries using SECAM refer to the worldwide comparison.

3.1 Interlacing

Concerning the Interlacing there are used two fields (half-images, half-frames, interlaced) in contrary to one frame (full-frame,

progressive).

Upper field (top) - all odd lines (1,3,5,7, etc.) Lower field (bottom) - now all even lines As looking at the TV one recognizes a picture are drawn first. (2,4,6,8, etc.) are drawn. like the one above.

The lines will be written from the left to the right starting with line 1. The first half-image is represented by the odd lines whereas the

second half-image consists of all even lines. If we put these half-images together we get 25 frames per second on PAL. For the half- images are delayed mutually and the picture tube afterglows for a certain time, wherefore the human eye has the impression of seeing

50 "full" pictures per second. Of course, these half-images are transferred without the white lines which are seen in the picture above.

It was one aim to save some bandwidth by the half-image transmission. This is the reason why fields (example: 704x240 pixel in ATSC format 480i) are only half as large as frames (example: 704x480 pixel in ATSC format 480i).

3.2 Interlaced

Usual televisions, video recorder (VCRs), video cassettes (VHS - video home system; in the past also known as vertical helical scan), video cameras and usual DVD players need or display interlaced material.

There are also produced DVDs completely interlaced, e.g. most sport DVDs, many music DVDs, adult films and TV series published on

DVD. One also finds low budget movies shot with a video camera in an interlaced state. Furthermore many "making of" documentations and specials on DVDs are completely interlaced.

3.3 Progressive

LCD displays, plasma displays, CRT/DLP/LCD/LCOS projectors and PC monitors can write only progressive pictures. If interlaced material is presented at these devices it has to be converted for progressive displays first.

"NTSC progressive" and "PAL progressive" are standards for hardware DVD players which support full-frame output.

3.4 Deinterlacing

Reassembling two fields to a frame again is called deinterlacing. With progressive devices such as PC monitors two fields will become converted to a frame first and then all lines of the frame (1, 2, 3, 4, etc.) will be written. 50 fields/s (interlaced) will become 25 fps

(progressive). Using a special deinterlacing we achieve 50 fps from 50 fields/s input since in each field the missing lines will be interpolated.

For the sake of brevity we will not discuss several deinterlacing methods like Blend, Weave, Discard, Motion Blur, Bob, Progressive Scan or Motion Compensation.

4.1 FILM-PAL-NTSC-Transfer

We begin with "FILM" in the center of the diagram (fig. 2). Film material is shot in 24 fps. A film frame is nominally displayed for 1/24 s

≈ 41.67 ms. One second of the film contains 24 frames and will be disassembled ("telecined") into 48 fields. For the transfer onto PAL the film is simply accelerated. PAL needs 50 fields/s. Two fields ( : n1 and n2) of the 2nd second of the film are still "pressed" into the first second - marked-off with the red dotted line - of the PAL video. Thus the so-called PAL Speedup emerges. PAL films are played 25/24 ≈ 4,167 % faster than the original film in the cinema. We can also say that the PAL length is 24/25 times longer compared to the original film. That means that the PAL length is 4 % shorter. Due to the acceleration of the film some people notice that the tone pitch is increased with PAL films. Two fields are displayed within 1/25 s = 40 ms.

50 fields/s are needed for an interlaced display and these fields will be shown in the order a1, a2, b1, b2, etc. Concerning a progressive display the fields will be added up first and then displayed in 25 fps (a1+a2, b1+b2, c1+c2, etc.). In the case of a progressive display

with 50 fps each field is converted into one frame by adding missing lines of each field due to

special deinterlacing. Thus a1, a2, b1, b2, etc. become A1, A2, B1, B2, etc.

The transfer from film to NTSC is a more complicated matter. In the chart (fig. 1) we recognize

that the "x2 field" already overlaps the first second ( : x2). The NTSC refresh rate is 29.97 fps

corresponding to 59.94 fields/s. We note that there are not 60 but 59.94 fields per second transferred.

The first two fields (a1, a2) are displayed in 1/29.97 s ≈ 33.37 ms. The three following fields are displayed in 1/19.98 s ≈ 50.05 ms.

Together the result for the first five fields is approx. 83.42 ms which represents a deceleration compared to the first two film frames

(2*41.67 ms = 83.34 ms). The film frames A and B are displayed approx. 0.08 ms longer in the NTSC television.

The following section "telecining" describes the achievement of 59.94 fields/s from 24 fps film material. 4.2 The Telecine technic (Telecining) Normal motion picture films are shot in 24 fps on 35 mm film material. Many output devices like conventional, old televisions need an interlaced signal the preservation of which is provided by the Telecine procedure. That is frames are converted into fields.

With PAL a frame is converted into two fields or 25 frames are converted into 50 fields within a second respectively.

With NTSC the film master is decelerated to 23.976 fps [to be more exact: 24*(1000/1001) = 23,9760239760239760... ≈ 23,976

(concerning this refer an explanation for the NTSC-Standard in the text above)].

Using the 2:3-Pulldown 59.94 fields/s are attained from 23.976 fps. This procedure alternatingly gives two and then three fields from the respective frames. First two fields (a1, a2) of frame A are produced and afterwards three fields (b1, b2, b1) of frame B etc.

Mathematically illustrated "2.5 fields per film frame" are transferred. If the film master is already slowed down, 23.976 whole pictures per second become 11.988*2 + 11.988*3 = 59.94 half-images per second whereby [23.976/2 = 11.988]. The display speed in NTSC television is about 0.1 % [23.976 fps/24 fps = 0.999] smaller than in the original film. We can also say that the NTSC film length is

24/23.976 ≈ 1.001 times the original film length.

We recognize the fields a1 and a2 generating the first frame A while the fields b1 and b2 generate the second frame B. But the following fields b1 and c2 generate neither frame B nor frame C. If objects of the film move during these two fields comb artifacts and frayed picture edges could appear. Since fields are repeated in NTSC television the picture - roughly speaken - changes between "fast and slow sections". The consequence is a jerky sequence of screens, the so-called "Motion Judder".

4.3 Inverse Telecine (IVTC)

Inverse Telecine is the process undoing the Telecining. On NTSC the additionally inserted fields are removed by IVTC whereby 59.94 fields/s or 29.97 fps respectively are transformed again to 23.976 fps. As two top or bottom fields cannot be written one behind the other the fields must always be present in the order top, bottom, top, bottom, etc. During the IVTC the fields are sorted. Thus the c1 field is arranged before the c2 field which can be seen in the part "IVTC (1)" of the diagram above - in contrast to the situation after the

2:3-Pulldown.

The surplus fields are also removed by performing another type of the IVTC. But this time a whole, compound frame is additionally duplicated. Each fourth frame is represented twice: e. g. the compound fourth frame D is twice displayed. Again frame H is displayed twice after 4 frames, etc. This procedure has the consequence that a refresh rate of 29.97 fps adjusts itself. This differs from the film material after 2:3-Pulldown in the way that all fields are played in the correct order but a compound frame is displayed twice (see "IVTC

(2)" in the diagram above). After the IVTC the pictures are in a progressive condition and they are no longer "telecined".

Genuine interlaced video material should not pass an IVTC process since putting fields together - recorded at different times - is not recommended. IVTC should be accomplished for optimal results only if the source which was divided into half-images is genuine 24 fps film material or genuine progressive material.

4.4 Overview of the refresh rates Overview of the frame rates, refresh rates

medium type frame rate, refresh rate converter

PAL DVD-Film 25 fps

DVD-Specials 25 fps

TV, VHS 25 fps, 50 fields/s

NTSC DVD-Film* 24 fps

DVD-Specials* 23.976 fps, 29.97 fps (2:3- Pulldown, Flags)

TV, VHS 23.976 fps, 29.97 fps (2:3- Pulldown, "mechanical"), 59.94 fields/s

High Blu-ray Disc (BD) [Film]* 24 fps Definition HD DVD [Film]* 24 fps (HD)

Cinema Motion Picture Film 24 fps (nominal)

Table 1: Overview of the refresh rates

* referred to usual conditions. Additionally, consider the ultimate comments at the end of this document and the following description of the MPEG format with respect to the refresh rate of NTSC DVDs.

5.1 MPEG (Moving Picture Experts Group), Layer and Picturetypes

Coming soon. Read this chapter in german.

5.2 MPEG-2 and T_F_F/R_F_F/FPS Flags

The format MPEG-2 is used for Video DVDs. In the MPEG-2 stream the video material is not stored "telecined" since we would have double fields on NTSC only wasting memory capacity. MPEG-2 offers an intelligent solution for programming flags. Contrary to NTSC

VHS and television no redundant fields are stored or transferred. Due to the flags DVD players will set the double fields in the same interval as a "mechanically" produced Telecine process would have added them before.

The T_F_F (top field first) and R_F_F (repeat first field) flags cause the fields to be repeated in a certain order. The top field (a1, fig. 15) of frame A is displayed first (T_F_F 1) and the first field (a1) will not be repeated (R_F_F 0). The top field (b1) of frame B is displayed first (T_F_F 1) and the first field (b1) will be repeated (R_F_F 1). The top field (c1) of frame C is not displayed first (T_F_F 0) and the first field (c2) will not be repeated etc.

In our case (fig. 15) the T_F_F sequence is 1100110011... and the R_F_F sequence is 0101010101...

This procedure is called 2:3-Pulldown due to the repetition of the fields of the accessory frames in a certain order: two fields (a1, a2) of the first frame (A) and three fields (b1, b2, b1) of the second frame (B) etc. Often this procedure is also called 3:2-Pulldown, but however it is more comprehensible to say 2:3-Pulldown if starting with 2 fields of the first frame.

The setting of the R_F_F and T_F_F flags is not sufficient; more precisely, the usually 24 fps encoded MPEG stream stored on DVD is actually not played in 29.97 fps as needed for NTSC. The solution is simpler than one would first assume: in the videostream a FPS flag will be set. If this FPS flag is set to 29.97 fps the DVD player will recognize this setting and accurately play the stream in 29.97 fps. Here it is useful to consider the display speed of the stream to be "29.97 Hz" as a more intuitive quantity than the 29.97 fps since the real speed of the movie is not changing. For a more detailed consideration refer to chapter 3 of the FAQ.

5.3 Video Time Code Counters and Drop Frame Flag/Non Drop Frame Flag

Video time code counters can only count in whole frames. An example for a video time code - also called SMPTE time code - is

[01:42:55:23] denoting [hours:minutes:seconds:frames]. The NTSC refresh rate is 29.97 fps. That means that one second of the video time code counter would be a little faster than the real second of the film (second in SI-System).

The drop frame flag or non drop frame flag has a special task with NTSC video. At the beginning of each minute (except zero minutes and multiples of ten minutes: 0, 10, 20, 30, 40, 50, etc.) on drop frame MPEG streams the frames 0 and 1 on the video time code are passed ("dropped"). So this procedure will be done only between integer valued minutes, in particular 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, etc. It is important that only the frames 0 and 1 on the video time code are passed - not the real film frames 0 and 1.

For example the video time code jumps from [00:01:59:29] to [00:02:00:02] instead of [00:02:00:00]. The drop frame flag is set to synchronize the video time code with the real time.

In 100 min. real time 10*9*(2 [two frames: 0 and 1]) = 180 frames are passed in the video time code counter. The video time code counter can only count 30 whole frames per second at standard NTSC. This yields 180 frames/30s = 6 fps. 100 film minutes - programmed as drop frame MPEG - are also displayed accurately on the video time code in 100 min. One second of the video time code is about 0.03 fps faster than the real NTSC film second [30 fps - 29.97 fps = 0.03 fps]. Auxiliary calculation: 0.03 fps*6000 s = 180 frames. These 180 frames actually compensate the frames that are passed.

Therefore, non drop frame MPEGs would display 100 film minutes (real time) as 100 min. and 6 sec. on the video time code. 6. PAL-60

In the last years the available televisions are usually multi-standard devices. They can display both NTSC and PAL or SECAM signals. If a television is not multi-standard and a NTSC DVD is played at a PAL television there also exists the possibility of the DVD player showing

NTSC as PAL-60. This standard is also called "pseudo PAL" or "NTSC playback on PAL TV". PAL-60 uses the color coding/color subcarrier of PAL but the number of scan lines (525) as well as the refresh rate of NTSC. However, the refresh rate is not 60 Hz as one could assume due to the notion, but 59.94 Hz. We must pay attention that not all DVD players/PAL televisions can transmit/display PAL-60.

7.1 Digital Television

For terrestrial broadcasting of digital TV programs three competing systems are used (tab. 2).

In Japan the ISDB-T (Terrestrial Integrated Services Digital Broadcasting) system is standardized by ARIB (Association of Radio

Industries and Businesses) (ISDB formats).

A system which uses an 8 VSB modulation (8 Level Vestigial Side Band) for terrestrial broadcasting, standardized by ATSC, has been realized in the USA (ATSC formats).

The DVB Project has been realized in Europe by EBU (European Broadcasting Union), ETSI (European Telecommunications Standards

Institute) and the CENELEC (European Committee for Electrotechnical Standardization) (DVB formats MPEG-2/H.264 AVC). For terrestrial broadcasting the DVB-T (Digital Video Broadcasting Terrestrial) standard is used.

Country System

USA, Canada, South Korea ATSC

Japan ISDB-T

Australia, Belgium, Finland, France, Germany, Italy, Namibia, Netherlands, Russia, Singapore, Spain, Sweden, Switzerland, DVB-T

Taiwan, United Kingdom (Great Britain [England, Scotland, Wales] and Northern Ireland) (Elaborate overview of all worldwide

systems)

Table 2: Worldwide use of digital terrestrial television

7.2 LDTV, SDTV, EDTV and HDTV

Television formats can be subdivided into different categories like LDTV, SDTV, EDTV and HDTV. Half-images will be transferred in SDTV

(Standard Definition Television). SDTV is hierarchically arranged under EDTV (Enhanced Definition Television). Here, progressive material is transferred instead of interlaced material.

HDTV (High Definition Television) which is already used in the USA is desired to replace our old analog PAL and NTSC television formats.

Nowadays a resolution of 1920x1080 pixel (progressive, frame rate 23.976, 24, 25, 29.97, or 30, format 1080p) is already possible.

7.3 ATSC (Advanced Television Systems Committee)

At present, the standardized digital formats subdivided in SDTV and HDTV are represented in tab. 3:

ATSC formats

format horizontal vertical scan aspect scan mode frame rate

pixels lines ratio

HDTV 1080p 1920 1080 * 16:9 progressive 23.976 Hz

1080p 1920 1080 * 16:9 progressive 24 Hz

1080p 1920 1080 * 16:9 progressive 29.97 Hz

1080p 1920 1080 * 16:9 progressive 30 Hz

1080i 1920 1080 * 16:9 interlaced 29.97 Hz

1080i 1920 1080 * 16:9 interlaced 30 Hz

720p 1280 720 16:9 progressive 23.976 Hz

720p 1280 720 16:9 progressive 24 Hz

720p 1280 720 16:9 progressive 29.97 Hz

720p 1280 720 16:9 progressive 30 Hz

720p 1280 720 16:9 progressive 59.94 Hz

720p 1280 720 16:9 progressive 60 Hz

SDTV 480p 704 480 16:9 progressive 23.976 Hz

480p 704 480 16:9 progressive 24 Hz

480p 704 480 16:9 progressive 29.97 Hz

480p 704 480 16:9 progressive 59.94 Hz

480i 704 480 16:9 interlaced 29.97 Hz

480i 704 480 16:9 interlaced 30 Hz

480p 704 480 4:3 progressive 23.976 Hz 480p 704 480 4:3 progressive 24 Hz

480p 704 480 4:3 progressive 29.97 Hz

480p 704 480 4:3 progressive 59.94 Hz

480i 704 480 4:3 interlaced 29.97 Hz

480i 704 480 4:3 interlaced 30 Hz

480p 640 480 4:3 progressive 23.976 Hz

480p 640 480 4:3 progressive 29.97 Hz

480p 640 480 4:3 progressive 59.94 Hz

480i 640 480 4:3 interlaced 29.97 Hz

480i 640 480 4:3 interlaced 30 Hz

Table 3: Standardized ATSC formats (USA)

* Considering these formats it should be mentionend that in reality 1088 lines are encoded in order to be sufficient for the MPEG-2 standard. The encoded vertical height must be divisible by 16 (progressive scan mode) or 32 (interlaced scan mode). The lowest 8 lines are black due to the MPEG standards.

Consider the complete overview of countries using ATSC.

7.4 DVB (Digital Video Broadcasting)

The DVB formats with MPEG-2 screen resolution standardized by EBU (European Broadcasting Union) and ETSI (European

Telecommunications Standards Institute) in these days are subdivided into HDTV, SDTV and LDTV in tab. 4:

DVB formats (MPEG-2 screen resolution)

format horizontal vertical scan aspect scan mode frame rate

pixels lines ratio (Hz)

HDTV 1152i(2) 1440 1152 16:9 interlaced 25

1080p 1920 1080 * 16:9 progressive 23.976 1080p 1920 1080 * 16:9 progressive 24

1080p 1920 1080 * 16:9 progressive 29.97

1080p 1920 1080 * 16:9 progressive 30

1080i 1920 1080 * 16:9 interlaced 29.97

1080i 1920 1080 * 16:9 interlaced 30

1080p 1920 1080 * 16:9 progressive 25

1080i 1920 1080 * 16:9 interlaced 25

1035i 1920 1035(1) 16:9 interlaced 25

1035i 1920 1035(1) 16:9 interlaced 29.97

1035i 1920 1035(1) 16:9 interlaced 30

720p 1280 720 16:9 progressive 23.976

720p 1280 720 16:9 progressive 24

720p 1280 720 16:9 progressive 29.97

720p 1280 720 16:9 progressive 30

720p 1280 720 16:9 progressive 59.94

720p 1280 720 16:9 progressive 60

720p 1280 720 16:9 progressive 25

720p 1280 720 16:9 progressive 50

SDTV 576p(2) 720 576 16:9 progressive 24

576p 720 576 16:9 progressive 25

576p 720 576 16:9 progressive 50

576p(2) 720 576 4:3 progressive 24

576p 720 576 4:3 progressive 25

576p 720 576 4:3 progressive 50

576i 720 576 16:9 interlaced 25

576i 720 576 4:3 interlaced 25

576p 544, 480, 352 576 16:9, 4:3 progressive 24(2), 25

576i 544, 480, 352 576 16:9, 4:3 interlaced 25

480p 720 480 16:9, 4:3 progressive 23.976, 24, 29.97, 30, 59.94, 60

480i 720 480 16:9, 4:3 interlaced 29.97, 30 480p 640 480 4:3 progressive 23.976, 24, 29.97, 30, 59.94, 60

480i 640 480 4:3 interlaced 29.97, 30

480p 544, 480, 352 480 16:9, 4:3 progressive 23.976, 29.97

480i 544, 480, 352 480 16:9, 4:3 interlaced 29.97

LDTV 288p 352 288 16:9, 4:3 progressive 24(2), 25

240p 352 240 16:9, 4:3 progressive 23.976, 29.97

Table 4: Standardized DVB formats (MPEG-2) of EBU/ETSI

(1) To satisfy the MPEG-2 standard the format 1035i is actually to be encoded with 1056 lines. 21 lines are black due to the MPEG standards while the

MPEG decoder outputs only 1035 active lines.

(2) These formats are defined only for contribution- and primary distribution applications.

Consider the complete overview of countries using DVB-T.

7.5 H.264/AVC (Advanced Video Coding)

The DVB formats with AVC screen resolution standardized by EBU (European Broadcasting Union) and ETSI (European

Telecommunications Standards Institute) in these days are represented in tab. 5:

DVB formats (AVC screen resolution)

format horizontal vertical scan aspect scan mode frame rate H.264/AVC level

pixels lines ratio (Hz)

1080p 1920, 1440, 1280, 960 1080 * 16:9 progressive 23.976, 24 4

1080p 1920, 1440, 1280, 960 1080 * 16:9 progressive 25 4

1080i 1920, 1440, 1280, 960 1080 * 16:9 interlaced 25 4

1080i 1920, 1440, 1280, 960 1080 * 16:9 interlaced 29.97, 30 4

720p 1280, 960, 640 720 16:9 progressive 23.976, 24, 4 29.97, 30, 59.94, 60 720p 1280, 960, 640 720 16:9 progressive 25, 50 4

576p 720 576 16:9, 4:3 progressive 50 4

576p 720, 544, 480, 352 576 16:9, 4:3 progressive 25 3

576i 720, 544, 480, 352 576 16:9, 4:3 interlaced 25 3

480p 720 480 16:9, 4:3 progressive 59.94, 60 4

480p 720, 640, 544, 480, 352 480 16:9, 4:3 progressive 23.976, 24, 3 29.97, 30

480i 720, 640, 544, 480, 352 480 16:9, 4:3 interlaced 29.97, 30 3

288p 352 288 4:3 progressive 25, 50 3

288i 352 288 4:3 interlaced 25 3

240p 352 240 4:3 progressive 23.976, 24, 3 29.97, 30, 59.94, 60

240i 352 240 4:3 interlaced 29.97, 30 3

Table 5: Standardized DVB formats (AVC) of EBU/ETSI

Consider the complete overview of countries using DVB-T.

7.6 ISDB (Integrated Services Digital Broadcasting)

At present, the standardized digital formats in Japan subdivided in SDTV and HDTV are represented in tab. 6:

ISDB formats1

format horizontal vertical scan aspect scan mode frame rate2

pixels lines ratio

HDTV 1125i 1920 1080 * 16:9 interlaced 29.97 Hz

1125i 1440 1080 * 16:9 interlaced 29.97 Hz

750p 1280 720 16:9 progressive 59.94 Hz

SDTV 525p 720 480 16:9 progressive 59.94 Hz

525i 720 480 16:9 interlaced 29.97 Hz 525i 544 480 16:9 interlaced 29.97 Hz

525i 480 480 16:9 interlaced 29.97 Hz

525i 720 480 4:3 interlaced 29.97 Hz

525i 544 480 4:3 interlaced 29.97 Hz

525i 480 480 4:3 interlaced 29.97 Hz

Tabelle 6: ARIB's standardized ISDB formats (Japan)

1 Tab. 6 shows the ISDB formats if the screensize was not defined by the command Sequence_Display_Extension. If the screensize is defined by

Sequence_Display_Extension further formats with screen ratio 4:3 and different vertical heights and horizontal widths are possible.

2 The output of 24 fps film material is not explictly defined in the ARIB standard. Due to the control of the Progressive_Frame flag and the R_F_F and

T_F_F flags of the MPEG-2 video stream an original frame rate of 24 fps can be imposed.

Consider the complete overview of countries using ISDB-T.

8. Ultimate Comments

The frame rate of a motion picture film is 24 fps corresponding to 48 fields/s. On a NTSC DVD the MPEG-2 material is also usually encoded in 24 fps (48 fields/s). Normally, T_F_F and R_F_F flags are not used by PC software DVD players. These flags are ignored since they would make no sense in the progressive PC operation. Therefore, the frame rate of a usual motion picture film on NTSC DVD is 24 fps. But with MPEG-2 the frame rate or refresh rate always depends on coding. For this special topic refer to the MPEG/FPS section above.

In order to avoid audio flutter during transmission the NTSC television is transferred in 29.97 fps (59.94 fields/s) or 23.976 fps respectively. For detailed information of the exact refresh rates refer to the explanations for the NTSC-Standard and the Telecining in the text above.

The MPEG stream of PAL DVDs is encoded in 25 fps.

Regarding the FILM and NTSC run time output of the "PAL-NTSC-FILM-Converter" it must be mentioned here that the run time of usual motion picture films on NTSC DVDs does not correspond to the "NTSC run time" but to the "FILM run time"! This circumstances apply to

NTSC DVDs the MPEG stream of which is encoded as well as stored on the DVD in 24 fps.

A motion picture film which runs e.g. 116 min. on a PAL DVD will not run 120 min. and 57 sec. on a NTSC DVD but 120 min. and 50 sec. Consider also the FAQ for conversion of play times.

9. Examples

The following overview (tab. 3) shows some results of the test scores to clarify the statements which are listed above.

PAL version (DVD) NTSC version (DVD)

run time [min:sec] run time [min:sec]

Example "Ultimate Comments" "Ultimate Comments"

116:00 120:50

American Psycho (1999) UK version, RC2, Rated: BBFC 18, uncut, HK version, RC3, Rated: Unrated/Not Rated, uncut,

Entertainment in Video Hong Kong Official DVD

97:49 101:53

Blade (1998) German version, RC2, Rated: FSK 18, uncut, BMG US version, RC1, Rated: R, uncut, New Line Platinum

Video, Deluxe Edition Series

115:17 120:05

Blade II (2002) German version, RC2, Rated: FSK 18, uncut, Warner US version, RC1, Rated: R, uncut, New Line Platinum

Home Entertainment Series

112:01 116:42

Blade: Trinity (2004) UK version, RC2, Rated: BBFC 15, (uncut), US version, RC1, Rated: R, (uncut), New Line

Entertainment in Video Platinum Series

Theatrical Version 108:14 112:44

Blade: Trinity (2004) UK version, RC2, Rated: BBFC 15, uncut, US version, RC1, Rated: Unrated/Not Rated, uncut,

Extended Version/ Unrated Entertainment in Video New Line Platinum Series

Version 117:16 "Extended Version" 122:10 "Unrated Version"

Unbreakable (2000) German version, RC2, Rated: FSK 16, uncut, US version, RC1, Rated: PG-13, uncut, Touchstone

Touchstone Pictures Pictures

102:15 106:31

Table 3: DVD run times in PAL and NTSC versions

The denotation "uncut" means that the PAL and NTSC versions are not cut in any way. There is no difference between the versions in each case. So, there is no scene which can only be seen in one version. Furthermore, there is no difference in intros or end credits.

10. References

[1] ATSC Standard, Digital Television Standard (A/53), Revision C with Amendment No. 1 (2004), Advanced Television Systems

Committee [2] ISO/IEC IS 13818-2, MPEG-2 Video, International Standard (1996), International Organization for Standardization/International

Electrotechnical Commission

[3] ISO/IEC JTC1 CD 10918, Digital compression and coding of continuous-tone still images (1993), International Organization for

Standardization/International Electrotechnical Commission

[4] EBU/ETSI TS 101 154 V1.7.1 (2005-06) Technical Specification, Digital Video Broadcasting (DVB); Implementation guidelines for the use of Video and Audio Coding in Broadcasting Applications based on the MPEG-2 Transport Stream, European Broadcasting

Union/European Telecommunications Standards Institute

[5] EBU/ETSI TS 102 154 V1.2.1 (2004-05) Technical Specification, Digital Video Broadcasting (DVB); Implementation guidelines for the use of Video and Audio Coding in Contribution and Primary Distribution Applications based on the MPEG-2 Transport Stream, European

Broadcasting Union/European Telecommunications Standards Institute

[6] ARIB STD-B32 Version 1.5, ARIB Standard (2004), Video coding, audio coding and multiplexing specifications for digital broadcasting, Association of Radio Industries and Businesses

Special thanks go to Art Allison, National Association of Broadcasters (NAB)