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62-480: 576i is a standard-definition digital video mode, originally used for digitizing 625 line analogue television in most countries of the world where the utility frequency for electric power distribution is 50 Hz. Because of its close association with the legacy colour encoding systems, it is often referred to as PAL , PAL/ SECAM or SECAM when compared to its 60 Hz (typically, see PAL-M ) NTSC -colour-encoded counterpart, 480i . The 576 identifies

124-481: A commonly used version of 5 limit tuning have four different sizes, and can be classified as follows: The most frequently occurring semitones are the just ones ( S 3 , 16:15, and S 1 , 25:24): S 3 occurs at 6 short intervals out of 12, S 1 3 times, S 2 twice, and S 4 at only one interval (if diatonic D ♭ replaces chromatic D ♭ and sharp notes are not used). The smaller chromatic and diatonic semitones differ from

186-456: A diatonic and chromatic semitone in the tuning. Well temperament was constructed so that enharmonic equivalence could be assumed between all of these semitones, and whether they were written as a minor second or augmented unison did not effect a different sound. Instead, in these systems, each key had a slightly different sonic color or character, beyond the limitations of conventional notation. Like meantone temperament, Pythagorean tuning

248-546: A diminished seventh chord , or an augmented sixth chord . Its use is also often the consequence of a melody proceeding in semitones, regardless of harmonic underpinning, e.g. D , D ♯ , E , F , F ♯ . (Restricting the notation to only minor seconds is impractical, as the same example would have a rapidly increasing number of accidentals, written enharmonically as D , E ♭ , F ♭ , G [REDACTED] , A [REDACTED] ). Harmonically , augmented unisons are quite rare in tonal repertoire. In

310-519: A whole tone or major second is 2 semitones wide, a major third 4 semitones, and a perfect fifth 7 semitones). In music theory , a distinction is made between a diatonic semitone , or minor second (an interval encompassing two different staff positions , e.g. from C to D ♭ ) and a chromatic semitone or augmented unison (an interval between two notes at the same staff position, e.g. from C to C ♯ ). These are enharmonically equivalent if and only if twelve-tone equal temperament

372-465: A caustic dissonance, having no resolution. Some composers would even use large collections of harmonic semitones ( tone clusters ) as a source of cacophony in their music (e.g. the early piano works of Henry Cowell ). By now, enharmonic equivalence was a commonplace property of equal temperament , and instrumental use of the semitone was not at all problematic for the performer. The composer was free to write semitones wherever he wished. The exact size of

434-493: A family of intervals that may vary both in size and name. In Pythagorean tuning , seven semitones out of twelve are diatonic, with ratio 256:243 or 90.2 cents ( Pythagorean limma ), and the other five are chromatic, with ratio 2187:2048 or 113.7 cents ( Pythagorean apotome ); they differ by the Pythagorean comma of ratio 531441:524288 or 23.5 cents. In quarter-comma meantone , seven of them are diatonic, and 117.1 cents wide, while

496-519: A fundamental part of the musical language, even to the point where the usual accidental accompanying the minor second in a cadence was often omitted from the written score (a practice known as musica ficta ). By the 16th century, the semitone had become a more versatile interval, sometimes even appearing as an augmented unison in very chromatic passages. Semantically , in the 16th century the repeated melodic semitone became associated with weeping, see: passus duriusculus , lament bass , and pianto . By

558-450: A melodic half step, no "tendency was perceived of the lower tone toward the upper, or of the upper toward the lower. The second tone was not taken to be the 'goal' of the first. Instead, the half step was avoided in clausulae because it lacked clarity as an interval." However, beginning in the 13th century cadences begin to require motion in one voice by half step and the other a whole step in contrary motion. These cadences would become

620-440: A pitch ratio of 16:15 ( play ) or 1.0666... (approximately 111.7  cents ), called the just diatonic semitone . This is a practical just semitone, since it is the interval that occurs twice within the diatonic scale between a: The 16:15 just minor second arises in the C major scale between B & C and E & F, and is, "the sharpest dissonance found in the scale". An "augmented unison" (sharp) in just intonation

682-477: A resolution that is not considered to be either high or enhanced definition . Standard refers to offering a similar resolution to the analog broadcast systems used when it was introduced. SDTV originated from the need for a standard to digitize analog TV (defined in BT.601 ) and is now used for digital TV broadcasts and home appliances such as game consoles and DVD disc players. Digital SDTV broadcast eliminates

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744-477: A semitone depends on the tuning system used. Meantone temperaments have two distinct types of semitones, but in the exceptional case of equal temperament , there is only one. The unevenly distributed well temperaments contain many different semitones. Pythagorean tuning , similar to meantone tuning, has two, but in other systems of just intonation there are many more possibilities. In meantone systems, there are two different semitones. This results because of

806-650: A vertical resolution of 576 lines, and the i identifies it as an interlaced resolution. The field rate , which is 50  Hz , is sometimes included when identifying the video mode, i.e. 576i50 ; another notation, endorsed by both the International Telecommunication Union in BT.601 and SMPTE in SMPTE 259M , includes the frame rate , as in 576i/25 . In analogue television, the full raster uses 625 lines, with 49 lines having no image content to allow time for cathode ray tube circuits to retrace for

868-419: Is a broken circle of fifths . This creates two distinct semitones, but because Pythagorean tuning is also a form of 3-limit just intonation , these semitones are rational. Also, unlike most meantone temperaments, the chromatic semitone is larger than the diatonic. The Pythagorean diatonic semitone has a ratio of 256/243 ( play ), and is often called the Pythagorean limma . It is also sometimes called

930-401: Is a different, smaller semitone, with frequency ratio 25:24 ( play ) or 1.0416... (approximately 70.7 cents). It is the interval between a major third (5:4) and a minor third (6:5). In fact, it is the spacing between the minor and major thirds, sixths, and sevenths (but not necessarily the major and minor second). Composer Ben Johnston used a sharp ( ♯ ) to indicate a note

992-455: Is called hemitonia; that of having no semitones is anhemitonia . A musical scale or chord containing semitones is called hemitonic; one without semitones is anhemitonic. The minor second occurs in the major scale , between the third and fourth degree, ( mi (E) and fa (F) in C major), and between the seventh and eighth degree ( ti (B) and do (C) in C major). It is also called the diatonic semitone because it occurs between steps in

1054-551: Is employed in situations where the importance of preserving the speed of the video outweighs the need for image quality. Many movie enthusiasts prefer PAL over NTSC despite the former's speed-up, because the latter results in telecine judder , a visual distortion not present in PAL sped-up video. DVDLard states "the majority of authorities on the subject favour PAL over NTSC for DVD playback quality" . Also DVD reviewers often make mention of this cause. For example, in his PAL vs. NTSC article,

1116-410: Is no longer significant; in that context, 576i means only The 576i video format can be transported by major digital television formats, ATSC , DVB and ISDB , and on DVD , and it supports aspect ratios of standard 4:3 and anamorphic 16:9 . When 576i is used to transmit content that was originally composed of 25 full progressive frames per second (576p25 or 576p/25), the odd field of

1178-449: Is raised 70.7 cents, or a flat ( ♭ ) to indicate a note is lowered 70.7 cents. (This is the standard practice for just intonation, but not for all other microtunings.) Two other kinds of semitones are produced by 5 limit tuning. A chromatic scale defines 12 semitones as the 12 intervals between the 13 adjacent notes, spanning a full octave (e.g. from C 4 to C 5 ). The 12 semitones produced by

1240-421: Is the diminished octave ( d8 , or dim 8 ). The augmented unison is also the inversion of the augmented octave , because the interval of the diminished unison does not exist. This is because a unison is always made larger when one note of the interval is changed with an accidental. Melodically , an augmented unison very frequently occurs when proceeding to a chromatic chord, such as a secondary dominant ,

1302-429: Is the septimal diatonic semitone of 15:14 ( play ) available in between the 5 limit major seventh (15:8) and the 7 limit minor seventh / harmonic seventh (7:4). There is also a smaller septimal chromatic semitone of 21:20 ( play ) between a septimal minor seventh and a fifth (21:8) and an octave and a major third (5:2). Both are more rarely used than their 5 limit neighbours, although

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1364-467: Is used; for example, they are not the same thing in meantone temperament , where the diatonic semitone is distinguished from and larger than the chromatic semitone (augmented unison), or in Pythagorean tuning , where the diatonic semitone is smaller instead. See Interval (music) § Number for more details about this terminology. In twelve-tone equal temperament all semitones are equal in size (100 cents). In other tuning systems, "semitone" refers to

1426-531: The Baroque era (1600 to 1750), the tonal harmonic framework was fully formed, and the various musical functions of the semitone were rigorously understood. Later in this period the adoption of well temperaments for instrumental tuning and the more frequent use of enharmonic equivalences increased the ease with which a semitone could be applied. Its function remained similar through the Classical period, and though it

1488-467: The Pythagorean minor semitone . It is about 90.2 cents. It can be thought of as the difference between three octaves and five just fifths , and functions as a diatonic semitone in a Pythagorean tuning . The Pythagorean chromatic semitone has a ratio of 2187/2048 ( play ). It is about 113.7 cents . It may also be called the Pythagorean apotome or the Pythagorean major semitone . ( See Pythagorean interval .) It can be thought of as

1550-419: The diatonic scale . The minor second is abbreviated m2 (or −2 ). Its inversion is the major seventh ( M7 or Ma7 ). Listen to a minor second in equal temperament . Here, middle C is followed by D ♭ , which is a tone 100 cents sharper than C, and then by both tones together. Melodically , this interval is very frequently used, and is of particular importance in cadences . In

1612-482: The functional harmony . It may also appear in inversions of a major seventh chord , and in many added tone chords . In unusual situations, the minor second can add a great deal of character to the music. For instance, Frédéric Chopin 's Étude Op. 25, No. 5 opens with a melody accompanied by a line that plays fleeting minor seconds. These are used to humorous and whimsical effect, which contrasts with its more lyrical middle section. This eccentric dissonance has earned

1674-751: The ghosting and noisy images associated with analog systems. However, if the reception has interference or is poor, where the error correction cannot compensate one will encounter various other artifacts such as image freezing, stuttering, or dropouts from missing intra-frames or blockiness from missing macroblocks . The audio encoding is the last to suffer a loss due to the lower bandwidth requirements. Standards that support digital SDTV broadcast include DVB , ATSC , and ISDB . The last two were originally developed for HDTV , but are also used for their ability to deliver multiple SD video and audio streams via multiplexing . The two SDTV signal types are 576i (with 576 interlaced lines of resolution, derived from

1736-412: The perfect and deceptive cadences it appears as a resolution of the leading-tone to the tonic . In the plagal cadence , it appears as the falling of the subdominant to the mediant . It also occurs in many forms of the imperfect cadence , wherever the tonic falls to the leading-tone. Harmonically , the interval usually occurs as some form of dissonance or a nonchord tone that is not part of

1798-432: The sampling theorem , translates to about 720 pixels. This value is enough to capture all the original information present. In digital applications, the number of pixels per line is an arbitrary choice. Values above about 500 pixels per line are enough for a perceived quality equivalent to analogue free-to-air television; DVB-T, DVD and DV allow better values such as 704 or 720 (matching the maximum theoretical resolution of

1860-416: The 24 frames per second to the 30 fps frame rate, PAL speed-up results in the telecined video running 4% shorter than the original film as well as the equivalent NTSC telecined video. Depending on the sound system in use, it also slightly increases the pitch of the soundtrack by 72.401% of a semitone . More recently, digital conversion methods have used algorithms that preserve the original pitch of

1922-549: The European-developed PAL and SECAM systems), and 480i (with 480 interlaced lines of resolution, based on the American NTSC system). SDTV refresh rates are 25, 29.97 and 30 frames per second , again based on the analog systems mentioned. In North America, digital SDTV is broadcast in the same 4:3 fullscreen aspect ratio as NTSC signals, with widescreen content often being center cut . In other parts of

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1984-407: The [major] scale ." Play B & C The augmented unison , the interval produced by the augmentation , or widening by one half step, of the perfect unison, does not occur between diatonic scale steps, but instead between a scale step and a chromatic alteration of the same step. It is also called a chromatic semitone . The augmented unison is abbreviated A1 , or aug 1 . Its inversion

2046-513: The actual image and 16 pixels are reserved for horizontal blanking, though a number of broadcasters fill the whole 720 frames. The display ratio for broadcast widescreen is commonly 16:9 (pixel aspect ratio of 40:33 for anamorphic ); the display ratio for a traditional or letterboxed broadcast is 4:3 (pixel aspect ratio of 10:11). An SDTV image outside the constraints of the SMPTE standards requires no non-proportional scaling with 640 pixels (defined by

2108-423: The adopted IBM VGA standard) for every line of the image. The display and pixel aspect ratio is generally not required with the line height defining the aspect. For widescreen 16:9, 360 lines define a widescreen image and for traditional 4:3, 480 lines define an image. Semitone In a 12-note approximately equally divided scale, any interval can be defined in terms of an appropriate number of semitones (e.g.

2170-532: The break in the circle of fifths that occurs in the tuning system: diatonic semitones derive from a chain of five fifths that does not cross the break, and chromatic semitones come from one that does. The chromatic semitone is usually smaller than the diatonic. In the common quarter-comma meantone , tuned as a cycle of tempered fifths from E ♭ to G ♯ , the chromatic and diatonic semitones are 76.0 and 117.1 cents wide respectively. Extended meantone temperaments with more than 12 notes still retain

2232-414: The clock timing skew using an accurate self-adaptive algorithm resulting in effective removal of judder during panning caused by PAL pulldown including audio pitch correction via time-stretching with WASAPI Exclusive Mode and SPDIF AC/3 Encoding output modes. Standard-definition television Standard-definition television ( SDTV ; also standard definition or SD ) is a television system that uses

2294-442: The difference between four perfect octaves and seven just fifths , and functions as a chromatic semitone in a Pythagorean tuning . The Pythagorean limma and Pythagorean apotome are enharmonic equivalents (chromatic semitones) and only a Pythagorean comma apart, in contrast to diatonic and chromatic semitones in meantone temperament and 5-limit just intonation . A minor second in just intonation typically corresponds to

2356-405: The equal-tempered semitone. To cite a few: For more examples, see Pythagorean and Just systems of tuning below. There are many forms of well temperament , but the characteristic they all share is that their semitones are of an uneven size. Every semitone in a well temperament has its own interval (usually close to the equal-tempered version of 100 cents), and there is no clear distinction between

2418-539: The example to the right, Liszt had written an E ♭ against an E ♮ in the bass. Here E ♭ was preferred to a D ♯ to make the tone's function clear as part of an F dominant seventh chord, and the augmented unison is the result of superimposing this harmony upon an E pedal point . In addition to this kind of usage, harmonic augmented unisons are frequently written in modern works involving tone clusters , such as Iannis Xenakis ' Evryali for piano solo. The semitone appeared in

2480-407: The former was often implemented by theorist Cowell , while Partch used the latter as part of his 43 tone scale . Under 11 limit tuning, there is a fairly common undecimal neutral second (12:11) ( play ), but it lies on the boundary between the minor and major second (150.6 cents). In just intonation there are infinitely many possibilities for intervals that fall within

2542-782: The founder of MichaelDVD says: "Personally, I find [3:2 pulldown] all but intolerable and find it very hard to watch a movie on an NTSC DVD because of it." In the DVD review of Frequency , one of his reviewers mentions: "because of the 3:2 pull-down artefacts that are associated with the NTSC format (…) I prefer PAL pretty much any day of the week" . This is not an issue on modern upconverting DVD players and personal computers , as they play back 23.97 frame/s–encoded video at its true frame rate, without 3:2 pulldown. PAL speed-up does not occur on native 25 fps video, such as European productions that are shot on video instead of film. Software that corrects

576i - Misplaced Pages Continue

2604-804: The frame is transmitted first (this is the opposite to 480i ). Systems which recover progressive frames or transcode video should ensure that this field order is obeyed, otherwise the recovered frame will consist of a field from one frame and a field from an adjacent frame, resulting in 'comb' interlacing artifacts. Such progressive content can be marked using encoding flags , for example in DVDs or other MPEG2 based media. Motion pictures are typically shot on film at 24 frames per second. When telecined and played back at PAL's standard of 25 frames per second, films run about 4% faster. This also applies to most TV series that are shot on film or digital 24p. Unlike NTSC's telecine system, which uses 3:2 pulldown to convert

2666-408: The image. Nominal analog blanking should not be confused with overscan , as overscan areas are part of the actual 4:3 or 16:9 image. For SMPTE 259M-C compliance, an SDTV broadcast image is scaled to 720 pixels wide for every 480 NTSC (or 576 PAL) lines of the image with the amount of non-proportional line scaling dependent on either the display or pixel aspect ratio . Only 704 center pixels contain

2728-454: The irrational [ sic ] remainder between the perfect fourth and the ditone ( 4 3 / ( 9 8 ) 2 = 256 243 ) {\displaystyle \left({\begin{matrix}{\frac {4}{3}}\end{matrix}}/{{\begin{matrix}({\frac {9}{8}})\end{matrix}}^{2}}={\begin{matrix}{\frac {256}{243}}\end{matrix}}\right)} ." In

2790-407: The larger by the syntonic comma (81:80 or 21.5 cents). The smaller and larger chromatic semitones differ from the respective diatonic semitones by the same 128:125 diesis as the above meantone semitones. Finally, while the inner semitones differ by the diaschisma (2048:2025 or 19.6 cents), the outer differ by the greater diesis (648:625 or 62.6 cents). In 7 limit tuning there

2852-438: The minor diatonic semitone is 17:16 or 105.0 cents, and septendecimal limma is 18:17 or 98.95 cents. Though the names diatonic and chromatic are often used for these intervals, their musical function is not the same as the meantone semitones. For instance, 15:14 would usually be written as an augmented unison, functioning as the chromatic counterpart to a diatonic 16:15. These distinctions are highly dependent on

2914-405: The music theory of Greek antiquity as part of a diatonic or chromatic tetrachord , and it has always had a place in the diatonic scales of Western music since. The various modal scales of medieval music theory were all based upon this diatonic pattern of tones and semitones. Though it would later become an integral part of the musical cadence , in the early polyphony of the 11th century this

2976-489: The musical context, and just intonation is not particularly well suited to chromatic use (diatonic semitone function is more prevalent). 19-tone equal temperament distinguishes between the chromatic and diatonic semitones; in this tuning, the chromatic semitone is one step of the scale ( play 63.2 cents ), and the diatonic semitone is two ( play 126.3 cents ). 31-tone equal temperament also distinguishes between these two intervals, which become 2 and 3 steps of

3038-401: The next frame (see Vertical blanking interval ). These non-displayed lines can be used to transmit teletext or other services. In the digital domain, only the visible 576 lines are considered. Analogue television signals have no pixels; they are continuous along rastered scan lines, but limited by the available bandwidth. The maximal baseband bandwidth is around 6 MHz which, according to

3100-528: The original analogue system). Colour information is stored using the YCbCr colour space (regardless of the original PAL or SECAM colour system) with 4:2:2 sampling and following Rec. 601 colourimetry. Originally used for conversion of analogue sources in TV studios, this resolution was adopted into digital broadcasting or home use. In digital video applications, such as DVDs and digital broadcasting , colour encoding

3162-491: The other five are chromatic, and 76.0 cents wide; they differ by the lesser diesis of ratio 128:125 or 41.1 cents. 12-tone scales tuned in just intonation typically define three or four kinds of semitones. For instance, Asymmetric five-limit tuning yields chromatic semitones with ratios 25:24 (70.7 cents) and 135:128 (92.2 cents), and diatonic semitones with ratios 16:15 (111.7 cents) and 27:25 (133.2 cents). For further details, see below . The condition of having semitones

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3224-542: The piece its nickname: the "wrong note" étude. This kind of usage of the minor second appears in many other works of the Romantic period, such as Modest Mussorgsky 's Ballet of the Unhatched Chicks . More recently, the music to the movie Jaws exemplifies the minor second. In just intonation a 16:15 minor second arises in the C major scale between B & C and E & F, and is "the sharpest dissonance found in

3286-467: The range of the semitone (e.g. the Pythagorean semitones mentioned above), but most of them are impractical. In 13 limit tuning, there is a tridecimal ⁠ 2 / 3 ⁠ tone (13:12 or 138.57 cents) and tridecimal ⁠ 1 / 3 ⁠ tone (27:26 or 65.34 cents). In 17 limit just intonation, the major diatonic semitone is 15:14 or 119.4 cents ( Play ), and

3348-412: The same two semitone sizes, but there is more flexibility for the musician about whether to use an augmented unison or minor second. 31-tone equal temperament is the most flexible of these, which makes an unbroken circle of 31 fifths, allowing the choice of semitone to be made for any pitch. 12-tone equal temperament is a form of meantone tuning in which the diatonic and chromatic semitones are exactly

3410-472: The same, because its circle of fifths has no break. Each semitone is equal to one twelfth of an octave. This is a ratio of 2 (approximately 1.05946), or 100 cents, and is 11.7 cents narrower than the 16:15 ratio (its most common form in just intonation , discussed below ). All diatonic intervals can be expressed as an equivalent number of semitones. For instance a major sixth equals nine semitones. There are many approximations, rational or otherwise, to

3472-512: The scale, respectively. 53-ET has an even closer match to the two semitones with 3 and 5 steps of its scale while 72-ET uses 4 ( play 66.7 cents ) and 7 ( play 116.7 cents ) steps of its scale. In general, because the smaller semitone can be viewed as the difference between a minor third and a major third, and the larger as the difference between a major third and a perfect fourth, tuning systems that closely match those just intervals (6/5, 5/4, and 4/3) will also distinguish between

3534-416: The soundtrack, although the frame rate conversion still results in faster playback. Conversion methods exist that can convert 24 frames per second video to 25 frames per second with no speed increase, however image quality suffers when conversions of this type are used. This method is most commonly employed through conversions done digitally (i.e. using a computer and software like VirtualDub ), and

3596-438: The speed-up is available for those viewing 576i DVD films on their computers, WinDVD 's PAL TruSpeed being the most ubiquitous. However, this method involves resampling the soundtrack, which results in a slight decrease in audio quality. There is also a DirectShow Filter for Windows called ReClock developed by RedFox (formerly SlySoft) that can be used in a custom DirectShow Graph to remap the reference audio timing clock to correct

3658-528: The video into a pillarbox . The pixel aspect ratio is the same for 720- and 704-pixel resolutions because the visible image (be it 4:3 or 16:9) is contained in the center 704 horizontal pixels of the digital frame. In the case of a digital video line having 720 horizontal pixels (including horizontal blanking), only the center 704 pixels contain the actual 4:3 or 16:9 image, and the 8-pixel-wide stripes on either side are called nominal analog blanking or horizontal blanking and should be discarded when displaying

3720-419: The world that used the PAL or SECAM color systems, digital standard-definition television is now usually shown with a 16:9 aspect ratio , with the transition occurring between the mid-1990s and late-2000s depending on the region. Older programs with a 4:3 aspect ratio are broadcast with a flag that switches the display to 4:3. Some broadcasters prefer to reduce the horizontal resolution by anamorphically scaling

3782-401: Was not the case. Guido of Arezzo suggested instead in his Micrologus other alternatives: either proceeding by whole tone from a major second to a unison, or an occursus having two notes at a major third move by contrary motion toward a unison, each having moved a whole tone. "As late as the 13th century the half step was experienced as a problematic interval not easily understood, as

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3844-401: Was used more frequently as the language of tonality became more chromatic in the Romantic period, the musical function of the semitone did not change. In the 20th century, however, composers such as Arnold Schoenberg , Béla Bartók , and Igor Stravinsky sought alternatives or extensions of tonal harmony, and found other uses for the semitone. Often the semitone was exploited harmonically as

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