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57-663: Since the widespread introduction of the original PM5544 from the early-1970s, the Philips Pattern has become one of the most commonly used test cards, with only the SMPTE and EBU colour bars as well as the BBC 's Test Card F coming close to its usage. The Philips circle pattern was later incorporated into other test pattern generators from Philips itself, as well as test pattern generators from various other manufacturers. Equipment from Philips and succeeding companies which generate

114-672: A television test pattern used where the NTSC video standard is utilized, including countries in North America . The Society of Motion Picture and Television Engineers (SMPTE) refers to the pattern as Engineering Guideline (EG) 1-1990 . Its components are a known standard , and created by test pattern generators. Comparing it as received to the known standard gives video engineers an indication of how an NTSC video signal has been altered by recording or transmission and what adjustments must be made to bring it back to specification. It

171-406: A waveform monitor in luminance mode as a downward staircase from left to right. The graticule of a vectorscope is etched with boxes showing the permissible regions where the traces from these seven bars are supposed to fall if the signal is properly adjusted. Below the main set of seven bars is a strip of blue , magenta , cyan , and white or gray castellations. When a television receiver

228-408: A display on the front panel and is labelled PM5644 PALplus test pattern generator and bears the model number PM5644/85 . No other variations of this hardware are presently known. This design also generates the well known 16:9 colour circle pattern but unlike the previously mentioned G/90 and G/924 models, it is capable of encoding a PALplus signal. It also is capable of generating the 4:3 pattern of

285-572: A heavily modified version of the PM5544 called the GB2097 inspection chart . Later, another modification, anecdotally called PM5549 (the Philips PM5549 was an unrelated product) began to be used at the headends of some mainland Chinese cable television providers. The design of the original PM5544 is fairly complicated, with an array of analogue signal generators generating each component of

342-417: A horizontal span equal to the height of the picture. For example, on 4 by 3 inches (10.2 cm × 7.6 cm) monitor with 400 TVL, 200 vertical dark lines can be counted over 3 inches (7.6 cm) width on monitor (Note that the 3 inches (7.6 cm) of monitor height is used rather than the 4 inches (10 cm) of whole monitor width). TVL is an inherent quality of a camera or monitor, influenced by

399-475: A printed card, the Philips PM5544 generates the test patterns fully using electronic circuits, with separate paths for Y , R-Y and B-Y colour components ( Y ′ U V {\displaystyle Y'UV} ), allowing engineers to reliably test and adjust transmitters and receivers for signal disturbances and colour separation, for instance for PAL broadcasts. In simple terms,

456-726: A single configuration. Like its predecessor (the PM5644), customer specific patterns were offered. In 2001, shortly after the release of the PT5230, said product line was further divested to DK-Audio A/S (also based in Copenhagen, Denmark at the time). Other pattern generator products not included in the sale, but still under warranty or with active support plans such as the PM5644 and PM5534 were abandoned by ProTeleVision to be fulfilled by Arepa Test & Calibration . ProTeleVision became

513-446: A survey of the top standards of the organizations' first 100 years, SMPTE EG-1 was voted as the 5th-most important SMPTE standard. In a SMPTE color bar image , the top two-thirds of the television picture contain seven vertical bars of 75% intensity. In order from left to right, the colors are white or gray , yellow , cyan , green , magenta , red , and blue . The choice of white or gray depends on whether that bar's luminance

570-442: Is 100% or not. This sequence runs through all seven possible combinations that use at least one of the three basic color components of green, red, and blue, with blue cycling on and off between every bar, red cycling on and off every two bars, and green on for the leftmost four bars and off for the rightmost three. Because green contributes the largest share of luminance, followed by red, then blue, this sequence of bars thus appears on

627-588: Is 8-bit Studio R'G'B', so 10-bit data is not just a bitshift operation (that means multiply by 4) from 8-bit Y'PbPr, as usually the case. For example, for 75% Blue 28-212-120 would be just 112-848-480, but it is actually 111-848-481. Per ITU-R BT.2111-2 TABLE 2 An extended version of SMPTE Color Bars signal, developed by the Japanese Association of Radio Industries and Businesses as ARIB STD-B28 and standardized as SMPTE RP 219:2002 (High-Definition, Standard-Definition Compatible Color Bar Signal)

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684-483: Is a specification of an analog camera or monitor's horizontal image resolution . The TVL is one of the most important resolution measures in a video system. The TVL can be measured with the standard EIA 1956 resolution chart . TVL is defined as the maximum number of alternating light and dark vertical lines that can be resolved per picture height. A resolution of 400 TVL means that 200 distinct dark vertical lines and 200 distinct white vertical lines can be counted over

741-545: Is also used for setting a television monitor or receiver to reproduce NTSC chrominance and luminance information correctly. A precursor to the SMPTE test pattern was conceived by Norbert D. Larky (1927–2018) and David D. Holmes (1926–2006) of RCA Laboratories and first published in RCA Licensee Bulletin LB-819 on February 7, 1951. U.S. patent 2,742,525 Color Test Pattern Generator (now expired)

798-637: Is bypassed or faulty. This reveals the full contents of the central pattern elements, which are normally cropped. Anecdotally this pattern has been referred to as PM5538 however this was not a Philips pattern generator. It was used in some parts of the Middle East like Dubai 33 in the UAE and Jordan Radio and Television Corporation (JRTV) in Jordan . Starting from the 1980s, China Central Television and some provincial mainland Chinese broadcasters began using

855-498: Is graphically superimposed over the bars. Values of 75% (75/7.5/75/7.5) SMPTE ECR 1-1978 color bars as analog NTSC signals: Note: IRE units apply to both NTSC composite video and broadcast signals while mV values only apply to NTSC composite video. Values sourced from the Tektronix TSG95 test pattern generator manual For digital video sources , the 10-bit YCbCr values for SD color bars are based on

912-573: Is known. Around this time Philips exited the TV test equipment business, with the lab that developed these products independently incorporated as ProTeleVision Technologies A/S . All products were immediately rebranded ProTeleVision . The PT5230 was the first to exclusively carry the new brand and included an enhanced analogue pattern generator option – the PT8631, which was able to generate all Philips (NTSC and PAL) and FuBK patterns in both 4:3 and 16:9 in

969-422: Is set to filter out all colors except for blue, these castellations, combined with the main set of color bars, are used to adjust the color controls; they appear as four solid blue bars, with no visible distinction between the bars and the castellations if the color controls are properly adjusted. The bottom section contains a square of 100% intensity white and a rectangle of 7.5% intensity black, for use in setting

1026-492: The 75% gray horizontal bar in the middle is changed to grayscale stair steps. The values of 100% (100/0/100/0) SMPTE RP 219:2002 color bars (1.00 * 219 + 16 = 235) using BT.709 matrix coefficients (only white and black are the same using BT.601 matrix), taken from the standard: ITU-R Rec. BT.1729 specified the last two 100% colors, green and magenta. It also specified all 100% colors for BT.601 matrix, not only BT.709. Television lines Television lines ( TVL )

1083-514: The COLOR dataset of the TESTIMAGES archive. Later RP 219:2002 became RP 219-1:2014 , with RP 219-2:2016 and ARIB STD-B66 adding details for UHD. ITU-R Rec. BT.2111 and ARIB STD-B72 further added versions with PQ / HLG HDR transfer functions and wide color gamut (BT.2020), which additionally have 100% saturated colors at the top and BT.709 bars at right bottom and left bottom;

1140-399: The I and Q axes on the vectorscope if the chrominance signal is demodulated properly. These bars give rise to the former portion of the casual term bars and tone . Typically, a television network , TV station , or other originator of video programming transmits SMPTE color bars together with a continuous 1,000 Hz sine wave before sending program material, in order to assert ownership of

1197-590: The Netherlands), which was able to be exactly recreated. Around 1997 with the PM5644 nearing end of life, Philips began work on the final generation of hardware that would generate the circle pattern. The first in this series was the PT5210 , which through the PT8601 analogue pattern generator module, was able to generate a single complex pattern however only by special order. At least one circle pattern configuration

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1254-516: The PM5644 (widescreen versions only), PT5230 and PT5300 (with appropriate pattern generator modules installed) and the PM5420. There are two major variations of the 16:9 circle pattern. The original 1991 pattern contains high frequency components which were useful for testing widescreen televisions in factories, specifically 450/400 TVL diagonal lines and a sixth 5.8 MHz grating. This however made it sub-optimum for public broadcasts as these exceeded

1311-705: The PM5644 and later models were available. An HD (1080p) version of the Philips circle pattern was developed for the PT5300 via the PT8612 HD Signal Generator add-on. It was never formally integrated into the PT8612 thus was not offered for sale. A 1250 line HD-MAC version of the Philips circle pattern also exists. A variation of the PM5544/34 pattern has been recorded where the circle generator

1368-464: The PM5644 are known to exist, each with different purposes and capabilities: The earliest design shares the chassis and the sync module with the PM5631 colour generator and has 576 KB of pattern ROM (can be increased to 4.5 MB for multiple / more complex patterns). The pattern produced by these units is nearly identical to the PM5544. Differences are typically a result of design constraints of

1425-454: The PM5655. Some versions of it have been found which generate both Philips and FuBK patterns (4:3 and 16:9). It is not presently publicly known if this is standard or special functionality. Appearance of text is significantly different to the PM5644 and from experimentation with physical equipment it is considered likely to be responsible for at least one public transmission (from Nederland 3 in

1482-508: The SMPTE formula for Y from the NTSC system (Y = 0.299R + 0.587G + 0.114B). The following table show the expected digital values, for example when measured using a signal analyzer . Note: Values sourced from " Leader Teleproduction Test Volume 3 Number 4 - Digital Video Levels " The colors below are presented using sRGB transfer of CSS . Since sRGB is the standard colorspace for webpages and computer screens, this gives only an idea of

1539-498: The bandwidth of most PAL transmission systems. All pattern components of the PT5230/PT5300 were within the bandwidth of PAL B/G. Widescreen circle patterns were used by broadcasters such as RAI ( Italy ), BRT ( Belgium ), RTL-TVI (Belgium/ Luxembourg ), Ned3 ( Netherlands ), TVE ( Spain ) and KNR TV ( Greenland ). Although no public transmissions are known to exist as of November 2024, an NTSC widescreen version of

1596-490: The black tones into grays or collapsing picture information into the signal clipping that occurs a small distance below the black level (known as crushing the blacks ). When a monitor is properly adjusted, the rightmost pluge bar should be just barely visible, while the left two should appear indistinguishable from each other and completely black. Also in the bottom section are two sections that contain -In-phase and +Quadrature signals (see YIQ ), centered on black level and having

1653-611: The brand and type of generator used to produce it, as well as how the broadcaster has chosen to configure it. Some television stations have included a digital clock and/or date, as well as the station logo or ID, inside the circle. This practice was common in Asia and some parts of Europe , as well as in South Africa . The Philips circle pattern is geared towards the PAL colour-coding system, but SECAM versions do exist (for example, it

1710-499: The center by Hank Mahler (1936–2021) that was then submitted to the SMPTE TV Video Technology Committee for consideration as a SMPTE recommended practice. This improved test signal was published as the standard SMPTE ECR 1-1978 . Its development by CBS was awarded a Technology & Engineering Emmy Award in 2002. CBS did not file a patent application on the test signal, thereby putting it into

1767-453: The circle pattern are the PM5544, PM5534, PM5535, PM5644, PT5210, PT5230 and PT5300. Other related (non circle pattern) test card generators by Philips are the PM5400 (TV serviceman) family, PM5515/16/18, PM5519 , PM5520 (monochrome), PM5522 (PAL), PM5540 ( monochrome ), PM5547, PM5552 and PM5631. Rather than previous test card approaches that worked by a live camera or monoscope filming

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1824-487: The current ProTelevision Technologies (lowercase 'V') shortly thereafter signifying a shift exclusively to digital transmission products. DK-Audio (also known as DK-Technologies ) subsequently released the PT5300 , which superseded the PT5230, accepting all of its pattern generator modules and included many new options and features developed by DK-Audio . It was the last physical pattern generator directly descending from

1881-437: The displayed pattern provides reference levels of black, white and colour saturation, to which a receiver can be set. Displayed image geometry (image centering, correct proportions of the circle, etc.) can also be corrected. More technical adjustments are also possible. Main technical features of the test card: While the basic specifications of the pattern normally remain consistent, there are often small variations depending on

1938-416: The hardware or software generating the test cards. Variations exist for every video standard: PM5644G/00 (PAL-B/G), PM5644I/00 (PAL-I), PM5644M/00 (NTSC), PM5644L/00 (SECAM), PM5644P/00 (PAL-M), PM5644N/00 (PAL-N). This model is able to replace every type of PM55xx pattern generator. A variant generating a 625 line version of the “ Indian head ” pattern is known to exist. Two variations bearing

1995-816: The intended colors. They are not completely representative of how they look on TV displays, since these follow the ITU-R BT.1886 standard, specifying a different gamma correction value, and thus colors below will look darker on such a display, and those darker colors will be the reference ones. The off-by-one errors (for example 254 instead of 255 and 1 instead of 0) happen because the 8 bit Y'PbPr values were used when decoding to R'G'B', if you use 10-bit Y'PbPr that does not happen. Y'PbPr (and Y'CbCr ) values of 75% (100/0/75/0) SMPTE ECR 1-1978 color bars (0.75 * 219 + 16 = 180) using BT.709-2 matrix coefficients as written in RP 219:2002: The source data for 10-bit and 12-bit Y'PbPr

2052-554: The lower luminance bandwidth in the SECAM system. Likewise, there are 525-lines NTSC versions of the pattern. One of the NTSC variants, used in Philippines , Taiwan , Haiti and Japan (by NHK , with the multiburst gratings slightly modified for NTSC-J ), has a modified square wave near the top of the circle at 300 kHz and the multiburst gratings at 0.5, 1.0, 2.0, 3.0 and 4.0 MHz. ( WNYW 's configuration simply removed

2109-404: The luminance range. More modern versions of the pattern feature a PLUGE pulse . The white square lines up so that it is below the yellow and cyan bars, and on a waveform monitor this will show up with the white bar overlapping the peak of the yellow and cyan chroma at 100 IRE units. The pluge (short for picture line-up generation equipment) pulse is positioned within the black rectangle, below

2166-609: The model number PM5644 . The PM5644 further improves upon the PM5534 by reducing the overall size to just 1RU . It also differs from the previous PM5544 and PM5534 in that its pattern generating circuitry is entirely digital, stored in EPROM chips allowing easy customisation of patterns. The PM5644 (and later generators) patterns' were compiled using an array of in-house tools defined by vectors in MS-DOS batch files . Many variations of

2223-591: The model numbers PM5644G/50 ( PAL B / G ) and PM5644G/70 ( YCbCr ) were available programmed with the FuBK pattern. The earliest known PM5644 16:9 hardware is the PM5644G/90 and PM5644G/924 which use the same chassis and PCB as the 4:3 models, however, both are programmed with the well-known 16:9 circle pattern alongside several other simple patterns. They generate an anamorphic signal but do not support PALplus encoding. The last known design has controls and

2280-539: The original PM5544 to generate the Philips circle pattern. SECAM was not supported by any models from this series, leaving the PM5644L as the last SECAM variant. In 2005 the last ever custom Philips circle pattern was compiled by DK-Technologies for Danmarks Radio (DR) , the first to transmit it in 1970. In 2018 the PT5300 was discontinued. In 2022 the PT5300 (and PT5210/PT5230) were open sourced by DK-Technologies . SMPTE color bars SMPTE color bars are

2337-416: The original PM5544. The original PM5644 was accompanied by a service offered by Philips whereby customers could have the pattern customised. The most common type of pattern modification was a simple logo inserted in-place of the top station ID box. These models usually carry a three digit model suffix starting with '9' i.e. PM5644/9xx . In the mid-1990s Philips completed their final VITS generator/inserter,

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2394-729: The original as follows: The above specifications were incorporated back into standard Philips generators such as the PM5534I/00 and the PM5644I/00. The widescreen version of the Philips circle pattern was designed in 1991. It was only known to be used in PAL regions and retains the signals present in the original, and features additional signals to test signal and picture quality, including Television lines resolution, corner circles and correct overscan and image centering. Several different types of hardware are known to generate it, including

2451-405: The pattern continuously. Digital circuitry is used to sequence the outputs from each module into the final pattern. The circle is internally generated as a square and cropped according to coordinates defined in a 264x252 grid defining half of the circle. The original used magnetic core to store data for the circle, essentially a very small core rope memory. Suitable ROM chips were not available at

2508-658: The public domain for general use by the industry. An extended version of the SMPTE color bars, SMPTE RP 219:2002 was introduced to test HDTV signals (see subsection). Although color bars were originally designed to calibrate analog NTSC equipment, they remain widely used in transmission and within modern digital television facilities. In the current context color bars are used to maintain accurate chroma and luminance levels in CRT, LCD, LED, plasma, and other video displays, as well as duplication, satellite, fiber-optic and microwave transmission, and television and webcast equipment. In

2565-480: The rack footprint from 6RU/12RU to 3RU . The PM5534 was available as a variant with component video outputs (PM5535) and had two pattern effecting options: PM8503 text generator (station ID) and the PM8504 clock generator. The PM5534 was available in 6 different versions: PAL-G, PAL-I, PAL-M, PAL-N, SECAM and NTSC. Some time during the late-1980s Philips introduced a new design of colour pattern generator bearing

2622-430: The red bar (it is present in the illustration but may be hard to see). It comprises three small vertical bars, a rightmost one with intensity 4% above black level (11.5 IRE), a middle one with intensity exactly equal to black (7.5 IRE), and a leftmost one with intensity 4% below black (super-black or blacker than black , 3.5 IRE). The pluge pulse aids in adjusting the bottom of the luminance range to avoid either washing out

2679-401: The same gain as the color burst signal; these show up on the pattern as a square of very dark blue, and a square of very dark purple. On a vectorscope, they appear as two short lines ninety degrees apart. These are used to ensure that the television receiver is properly demodulating the 3.58 MHz color subcarrier portion of the signal. The vectors for the -I and +Q blocks should fall exactly on

2736-560: The side bars. Though as of November 2024 no surviving equipment or captures/recordings are known, a version of the pattern existed for the PAL-N system. It is expected to resemble the PAL-B/G pattern however with the gratings of the NTSC version. Test card G was a quasi-Philips pattern developed by the BBC. It is realised by the physical modification of standard PM5544 generators and differs from

2793-524: The side colour bars.) A second variation, used by CBC Montreal in Quebec , Canada , had different gratings and added extra colour bars. In addition to the 525-line NTSC pattern, a PAL-M version of the pattern was also offered for the Brazilian market. Although no public transmissions are known to exist as of November 2024, the pattern is identical to NTSC but also includes achromatic fields adjacent to

2850-467: The supporting equipment could be replaced by a PM5638 which fitted into a single 1RU unit. The physical configuration of the PM5544 depends upon its purpose. A common application was in TV factories where it was typically used in its most basic configuration with no optional extras. When used for broadcasting it was usually fitted with the PM5543 text generator which allowed broadcasters to display text in

2907-457: The time. Four-fold symmetry was used to minimise the memory requirements. Later versions replaced the core with ROM. The original PM5544 was not capable of generating a composite video signal by itself. At the time it was introduced three additional pieces of equipment were required: Over the years the physical implementation of this supporting equipment was refined, with later PM5544's only requiring two extra pieces of equipment: Eventually all

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2964-442: The transmission line or medium, and so that receiving stations and intermediary telecommunications providers may adjust their equipment. Likewise, producers of television programs typically record bars and tone at the beginning of a videotape or other recording medium so that the playback equipment can be calibrated . Often, the name or callsign of the TV station, other information such as a real-time clock, or another signal source

3021-577: The upper and lower black boxes. It was available in 4 versions (PAL-G, PAL-M, PAL-N & NTSC) and did not have the option of an in-pattern clock (first introduced in PM5534). In the late-1970s, Philips introduced the PM5534 which replaced the original PM5544. It was fundamentally a very similar design using a mixture of analogue and digital circuitry to generate the pattern, however it no longer required an external sync generator and colour encoder, reducing

3078-418: The visual bandwidth of the transmission system used. It should not be confused with the number of horizontal scanning lines of such systems, which e.g. 625 lines for the PAL system, 525 lines for the NTSC system. Since analog transmission of video is scan line -based, the same number of horizontal lines is always transmitted. However, several factors impede the ability to display fine detail within

3135-566: Was awarded on April 17, 1956, to Larky and Holmes. Later, the EIA published a standard, RS-189A , which in 1976 became EIA-189A , which described a Standard Color Bar Signal, intended for use as a test signal for adjustment of color monitors, adjustment of encoders, and rapid checks of color television transmission systems. In 1977, A. A. Goldberg, of the CBS Technology Center , described an improved color bar test signal developed at

3192-585: Was introduced to test HDTV signal with an aspect ratio of 16:9 that can be down converted to a SDTV color bar signal with an aspect ratio of either 4:3 or 16:9. The Color Bar signal is generated with unconventionally slow rise and fall time value to facilitate video level control and monitor color adjustments of HDTV and SDTV equipment. Digital test images generated following the RP 219:2002 specifications and adapted to perfectly fit 114 standard and non-standard resolutions for both 16bpp and 8bpp, are freely available in

3249-737: Was used by TVP in Poland , MTV in Hungary and TDF in France , without side bars, as well as ERT in Greece , VTV in Vietnam and Télé Sahel in Niger , with side bars). The most obvious difference is the absence of PAL specific test features (to two normally invisible outmost vertical bars). Less noticeable is the change to the multiburst gratings, instead at 0.8, 1.8, 2.8, 1.8 and 0.8 MHz due to

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