Digital data formats

The remotely sensed data acquired from the satellites are stored in different types 

Each of these formats is preceded on tape by header or tailer information, which consists of ancillary data about the date, altitude of the sensor, sun angle, and so on. This information is useful when the data is corrected geometrically or radiometri-cally. The data are normally recorded on nine-track CCTs with data density on the tape of 800, 1,600, or 6,250 bits per inch (bpi). 

This format requires that all data for a single band covering the entire scene be written as one file. Thus, if one wants the area in the center of the scene in four bands, 

In this format the data for bands are written line by line onto the tape (i.e., line 1 band 1, line 1 band 2, line 1 band 3, line 1 band 4). It is a useful format if all the bands are to be used in the analysis. If some bands are not of interest, this format will be inefficient, since it is necessary in BIL to read serially past all the unwanted data. 

In this format, the data for the pixel in all bands are written together. Taking the example of LANDSAT - MSS 4 band data every element in the matrix has 4 pixel values pixel 1,1, of band 1 pixel 1,1, of band 2 pixel 1,1 of band 3 pixel 1,1 of band 4, pixel 1,2 of band 1, pixel 1,2 of band 2, pixel 1,2 of band 3 pixel 1,2 of band 4 etc. This data format is of use if all the bands are to be used, otherwise it will be inefficient. This format is not very popular now it was extensively used by the EROS Data Center for LANDSAT scenes in initial stages. 

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An alternative method of retrieving the data from the Chronotox microprocessor is the use of a small, portable, battery-operated printer to obtain a digital data format. The dosimeter is inserted into the readout slot of the printer, and, first, a two-digit code displays the sensor program code. Next, the battery voltage of the microprocessor is printed to assure... 

The CD-I (compact disk-interactive) is a low cost alternative to the CD-ROM for the entertainment industry. CD-I is a subset of the CD-ROM standard data format. It allows the digital storage of data, audio, and video information in a form that permits rapid interaction with a computer. CD-I is compatible to CD-ROM and to CD-AD 0 = 120 mm. The definition of the CD-I format is put down in the Green Book (Philips/Sony). 

This concept is one of the most difficult to quantitate. There are some relatively explicit definitions of information content for electronic communications. (For example, the Nyquist theorem defines the minimum sampling rate required in order to preserve the maximum frequency information in a periodic signal. And, the relationships between digital encoding formats and information content of a data base can be quantitated.) However, for the general problem of evaluating the results of instrumental measurements of chemical systems, the definitions for information content of data are very clear. 

Thus, the migration of this parameter appeared to fail against the aeeeptanee criteria. By examining the data more closely, it can be found that the data formats between the two are different minutes and seconds (MassChrom) and digital minutes (Analyst). Therefore, we are not comparing like with like and the MassChrom values must be converted to digital minutes to make the eomparison valid. 

Neural network methods require a fixed length representation of the data to be processed. Vibrational spectra recorded usually fulfill this requirement. With most applications in vibrational spectroscopy, the spectral range and resolution are fixed, and a comparison of spectra from different sources is directly possible. Appropriate scaling of the spectra allows handling different resolutions to obtain the same number of components in a descriptor. Digitized vibrational spectra typically contain absorbance or transmission values in wave-number format. Most of the spectrometers provide the standardized spectral data format JCAMP-DX developed by the Working Party on Spectroscopic Data Standards from the International Union of Pure and Applied Chemistry (lUPAC) [48]. 

Center, San Antonio. SECM data files can also be converted into files that can be read by other commercial SPM instruments. The author wrote a program (available upon request) to convert SECM data hies to Nanoscope (Digital Instruments) format, making all the data analysis and display routines of the commercial software available. 

Nowadays it is common to ask also for a floppy disk or a magtape with the data in a standard format and, in addition, for the plotfile. Of course the cost should be included in the fee, since everybody knows that digital data processing is cheaper and not more expensive than manual work. The truth is that it can be very efficient once it runs, but to come to that stage can cost you a fortune and even more. 

Taylor, Jim, Mark R. Johnson, and Charles G. Crawford. DVD Demystified. 3d ed. New York McGraw-Hill, 2006. Covers basic technology as well as production and authoring processes. Describes the vast variety of competing video, audio, and data formats and explains how DVD standards and specs dovetail or clash with related digital-media standards. 

What are the input and output requirements of the system Specify all signal current and voltage ranges, logic levels, input and output impedances, digital codes, data rates, and data formats. 

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