DE2907834A1 - Digital recording of analogue signals - has control equipment to input address codes controlling recording parameters, using address codewords to determine amount of quantisation - Google Patents

Abstract

The equipment is for digitally recording analogue signals and for replaying the same digitally recorded signals in analogue form. The system comprises A/D conversion and recording of a control track in parallel with the information track for synchronisation purposes. The analogue signal is input to an A/D converter with a sampling frequency coming from the pulse generator through a frequency divider. Address codewords are input to decide the recording parameters and data formatting, these determine the amount of quantisation etc. The drive mechanis of the recorder are also coupled to the recording circuitry to ensure synchronisation.

Description

Process for the digital recording of analogs

Signals, in particular audio signals, and for analog reproduction of these digitally recorded signals The invention relates to a method for digital recording of analog signals, using an AD converter for converting the analog signals into one through various parameters such as sampling frequency, Pulse code, bit rate, etc. defined digital pulse train as well as using a recording medium with at least one useful signal track.

For digital signal storage, especially audio signals Various methods are known which differ in terms of their use for recording necessary parameters such as coding, formatting, sampling frequency, number of useful signal tracks more or less strong per channel, running speed of the recording medium, etc. differ from one another so that they are not compatible with one another. These lack of standardization has the consequence that one after a first Procedure with a correspondingly designed recording device stored signal cannot be played on another device on another system.

The present invention is now based on the object of a solution to show how with the least possible effort an optimal adaptation to the different Recording modes can be achieved.

Based on a method of the type specified in the introduction this is achieved according to the invention in that a address code word consisting of several freely selectable parameter values different, Control signals assigned to the individual parameters for influencing corresponding ones Function blocks are derived and that the address code word on the useful signals associated recording medium is recorded. This solution has the advantage that instead of a rigid definition a variable, but always controllable one Setting of the individual parameters is possible, with the one being selectable Recording mode necessary definition of the variable parameters by a dem the signal to be recorded takes place directly or indirectly assigned password.

Advantageous further developments of the concept of the invention are the subclaims removable.

Details of the invention are given below with reference to the drawing explained in more detail. 1 shows the block diagram of a circuit arrangement according to the invention for digital recording an analog signal, in particular one analog audio signal, FIG. 2 shows the block diagram of a circuit arrangement according to the invention for analog playback of a stored according to a freely selectable recording mode Digital signal.

The block diagram shown in FIG. 1 is based on the following of a recording process is explained.

An analog signal, e.g. an audio signal AS, arrives at the input an analog-to-digital converter AD, whose sampling frequency is e.g. Using a frequency divider 1 from a clock frequency generated in a clock generator 2 is derived. The clock frequency is assigned to the clock generator 2 by a Control unit 3 controlled.

Before entering the useful signal, however, the setting is made first the parameter functional units necessary for digital recording. this happens with the aid of an address code word AC; either directly, e.g. Be manually via a Input keyboard 4 or indirect, i.e.

externally via an interface 5 from a command carrier such as master recorder control track or the like. Is read. The address code word is now in a, preferably Functional unit 6 consisting of a microprocessor, in which an implementation of the Characteristic values contained in the address code word takes place in corresponding control signals. Through these control signals the following are in detail for the parameter or for whose link formatting influences essential function blocks: The block 7 contains a control stage for the selected quantization range, i.e. for the selected number of quantization levels at the maximum possible instantaneous value (sample) of the signal to be drawn. The following, Adding stage 8, which is also influenced by a control signal, is used to obtain a binary control word, which preferably consists of two consecutive samples (sample) derived at the output of the module 7 and for a later intended transmission error correction is used. The next step is a step 9 for obtaining a so-called Data cycle control eye sick word that consists of a designated data block Sampling sequence including the assigned control values is derived. Finally, the function unit 10 is used to recognize the data sampling sequence required binary synchronization word in one of the assigned control code signal corresponding shape and length generated. In a further functional unit 11 are the time code data generated in a time code generator 16 with additional information or control data JD / KD linked to an inter-block sample sequence, which is inserted between two useful signal data blocks. The functional unit 6 also controls the linking of the various auxiliary signals with the actual ones Useful signals.

This is done with the help of a control unit 12 with the following Switching stage 13. This switching stage 13 influences various switches S1 - S5 and although in any definable way, on the one hand the auxiliary signals of the modules 8, 9, 10, 11 and, on the other hand, the useful signals routed via module 7 with one another linked and in a single or multi-track data block formatting to a for The sequence that is optimal for the respective recording process is stored in a buffer 14 can be read in.

The address code word supplied to the functional unit 6 got also still in a link element 15, where it is with the time code generator 16 generated time code data is interleaved. This is made up of the code word and time code data resulting pulse train is finally a modulator stage 17 train t and synchronously for useful information in a modulation type corresponding to the recording medium material e.g. X in a control track running parallel to one or more useful signal tracks recorded.

The digital recording is now done in such a way that it grows out Address code word composed of several parameters is read from the code word then various control signals are used to influence the corresponding functional units derived, whereby the recording device to the specified by the code word Mode is set. Finally, the Nutzsi le with the parameter auxiliary signals linked and 2us m en with the time code signals with one through the individual parameters predetermined data block formatting in single or multi-track recording on one Carrier stored9 with the also by a control signal of the functional unit 6 with associated control unit 18 controllable speed of the recording medium optimally according to the number of bits and tracks specified by the recording mode is adjusted. By directly linking the mechanical recording medium speed with the parameters specified in the address code value, such as sampling frequency, number of bits per sample, clock frequency, etc.

thus an optimal packing density is advantageously achieved without Any loss of quality achieved.

The actual recording of the digital information finally takes place d a d u r c h that the @ig @ ale contained in the buffer memory 14 via an interface 19 to Adaptation to the number of data recording tracks determined with 6 read into the recording medium per useful signal and a modulator stage 20 will.

In Fig. 2, the basic circuit for the analog playback is the indicated with the aid of a device according to FIG. 1 recorded digital signals. First, from the address code word, which is either keyed in manually or but preferably read from a control track provided on the data carrier the control signals required for the individual parameter functional units generated. For this purpose it is read out together with the time code signals Address code word supplied via a decoder 21 to a separator 22 in which the Address code word is separated from the time code signals. In the following, Functional unit 23, preferably constructed as a microprocessor, are now from the Code word derived from several control commands, which in turn reflect the recording mode The setting of the respective parameter modules adapted to the digital recording cause. These control signals influence e.g. the control unit 24 for the respective required data carrier speed, as well as the control unit 25 for data block format decoding with the following switching stage 26, with which the in their through the address code word specified data formatting, the recorded useful signals are decoded accordingly and in this form read into a buffer 27 and then read out again will. Further control signals are for the decoder 28 (data carrier number of tracks per Nutzsigna, the sync pulse detector 29, the error correction stage 30 and finally intended for the digital-to-analog converter D / A. Regarding tape speed, track selection, Data block formatting, Bit rate, sample word length, sampling frequency etc. reproducing apparatus adapted to the respective recording mode of the digital signal is now ready for operation, the useful signals after the scanning of the carrier T initially a demodulator stage 31 are supplied. The output of the demodulator stage 31 is now on the one hand with a functional unit 32 for obtaining the clock frequency with an associated function cycle clock control unit 33 and on the other hand with the Decoder 28 connected. Via the buffer store 27 and the error correction stage 30, the digital useful information finally arrives at the digital-to-analog converter D / A, at the output of which the useful signal appears in analog form. About parallel to the Digital-to-analog converter D / A switched interface modules 34, 35 can also read out the various auxiliary signals JD / KD and the time code signal ZS will.

4 claims 2 figures

Claims (4)

Patent pending process for the digital recording of analog signals, in particular audio signals, using an AD converter, for conversion the analog signals into one through various parameters such as sampling frequency, pulse code, Bit rate, etc. defined digital pulse train as well as using a Recording medium with at least one useful signal track, d a d u r c h g e k e n n z e i c h -n e t that one of several free before the useful signal is recorded Selectable parameter values existing address code word is formed that from this Address code word various control signals assigned to the individual parameters to influence the corresponding function blocks and that the Address code word recorded on the record carrier assigned to the useful signals will. 2. The method of claim 1, d a d u r c h g e -k e n n z e i c h n e t that the address code word together with a time code signal in parallel is stored in a separate control track for useful information. 3. The method of claim 1, d a d u r c h g e -k e n n z e i c h n e t that the address code word is in free memory locations in coded form a data signal track (s) containing a single useful signal is recorded. 4. Process for analog reproduction of digitally recorded signals using a DA converter to convert one of several parameters such as sampling frequency, pulse code, bit rate, etc. specified digital pulse sequence in the corresponding analog values as well as using a playback device, d a d u r c h e k e n n z e i c h -n e t that from one possibly into at least a useful signal track and / or in a separate control track with recorded or Address code word newly entered before playback several, the individual parameters Control signals assigned to the useful signal recording for influencing the corresponding ones Function blocks of the playback device are derived and that the digital Useful signals in a mode defined by the function modules set can be reproduced as analog signals.