EP0231299A1

EP0231299A1 - Process for formatting video tapes

Info

Publication number: EP0231299A1
Application number: EP19860904775
Authority: EP
Inventors: Günther Krause; Ramin Azizi-Namini
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-08-06
Filing date: 1986-08-04
Publication date: 1987-08-12
Also published as: DE3528578A1; DE3528578C2; WO1987000958A1; JPS63500407A

Abstract

Dans un procédé de mise en forme de bandes vidéo (1) par l'intermédiaire de la piste vidéo et/ou audio, des signaux des numéros d'images (2) et d'autres données sont inscrits sur la piste vidéo et/ou audio. Afin d'assurer un positionnenent précis de l'image de manière rentable et efficace, et ainsi de fournir la base d'un contrôleur universel de magnétoscope comportant un système ordinateur de base, les signaux des numéros d'images sont introduits sur la piste vidéo et/ou audio par intervalles de temps (tb) et la région de la piste vidéo et/ou audio comprise entre les signaux des numéros d'images est utilisée pour inscrire d'autres données. Le numéro d'images réel peut être déterminé durant l'intervalle du temps en comptant les impulsions d'images sur la piste vidéo. Les signaux des numéros d'images sur la piste audio reproduisent uniquement l'état absolu du compteur d'images.In a method of shaping video tapes (1) via the video and / or audio track, signals of the image numbers (2) and other data are written on the video track and / or audio. In order to ensure precise positioning of the picture in a cost-effective and efficient manner, and thus to provide the basis for a universal VCR controller comprising a basic computer system, the signals of the picture numbers are introduced on the video track. and / or audio by time intervals (tb) and the region of the video and / or audio track between the signals of the image numbers is used to write other data. The actual frame number can be determined during the time interval by counting the image pulses on the video track. The image number signals on the audio track reproduce only the absolute state of the image counter.

Description

Processes for formatting video tapes

The invention relates to a method for formatting video tapes via the video and / or audio track, in which picture number signals and other data are written on the video and / or audio track.

A suitable formatting is of importance in order to achieve precise positioning, in particular with regard to controllers for controlling video tape devices by computers. Conventional controllers for controlling video tape devices essentially only have the possibility of positioning special video devices, so-called professional video recorders, by means of commands via a serial interface.

The previous controllers only use part of the possibilities that the coupling between computer and video recorder offers. The choice of devices that can be used is also limited. Another disadvantage is that an audio track is always required for image-accurate positioning, which is then no longer available to the user. This is particularly disadvantageous when it comes to training tapes that require both audio tracks for didactic reasons, for example in bilingual teaching tapes, or if there are devices with only one audio track, since in this case only the image signal is required for the application would be available. Previous positioning systems for video recorders (eg from the company BCD) only use the possibility of complete audio formatting. The aim of the present invention is to create a video recorder controller as a connection between a computer and a video device, wherein the possibilities of a video recorder for a computer system are to be developed as comprehensively as possible. In this case, it should be made possible to issue commands for positioning the video recorder via a standard interface of the computer.

From this target position, the closer object of the invention derives a method for formatting Video¬ bands according to ^'the initially mentioned type, which allows effectively forming an exact positioning as possible.

According to the invention, this object is achieved by the features resulting from the characterizing part of patent claim 1.

In particular, the following embodiments of the method according to the invention have proven to be suitable for image-accurate positioning.

In the event that an audio track for formatting

Is available, it can be formatted using a serial data stream.

If roughly available, the image control pulses can be used for the rough positioning and if the formatting pulses fail. In all other cases, the rough positioning is carried out using a time-distance function.

In the event that the audio track may not be used, the following embodiments of the method according to the invention come into consideration: • Formatting in the video track during the copying process or the production of the tape. Image information, in particular image number, is written into the blanking gap of the video signal as serial data.

2. Formatting in the video track as subsequent formatting. This is done in cases where there are no two video recorders available, or if a copy of one is for quality or other reasons _. standing video tape is not possible.

On the one hand, gray images are written at suitable intervals, the brightness value being averaged from a number of previous images in order not to impair the visual impression. The gray images contain the image information in the blanking interval.

On the other hand, a few images are read at suitable intervals, then temporarily stored and then written back together with the image information into the blanking space by means of the insert cut option at the same location.

In the event that the writing of the video track is also forbidden for legal or other reasons, the video tape is read completely once. Suitable features are calculated from the picture contents, then stored as a hash code in a table under the corresponding picture number. The positioning takes place in such a way that the corresponding hash code for the image contents is continuously generated from abstracted features during the playback and is then searched for in the hash table, which in turn returns the image information. The hash code table can either be stored at an unused location on the video tape or on a separate medium. In order to store any data, texts, tables of contents, etc., in cases in which the audio track may be used, it can be used for this purpose.

Since the fine positioning of the playback process takes several seconds due to the fact that the tape has to be threaded in and out, it is not necessary to write the image number in each (half) image, but in accordance with the invention it is sufficient to do this at larger intervals of, for example, 50 to 100 images. Any data can be written into the remaining images. The picture number information also does not need to be completely housed in a (half) picture, but it is advisable to distribute this information over several pictures in favor of secure data storage. However, in order to avoid sequence errors during overflow (e.g. 999 after 1000), the image number read in this way may only be updated after it has been completely received.

The method according to the invention enables image-precise positioning in a very effective manner, which is in no way affected by the fact that data can also be written between the formatting pulses. In particular, it has been found to be advantageous that, alternatively, the ^' image pulses can always be evaluated when the audio pulses are interrupted.

The image-accurate positioning is an important basis 110 for the desired universally usable video recorder controller, which consists of a basic computer system which has several parallel, one serial interface and at least one interrupt input.

Commands and 115 data can be exchanged between the controller and a computer with a corresponding interface via the serial interface. The parallel interfaces serve as an interface between the controller and the video tape recorder, the basic functions of the video recorder being able to be controlled 120 and certain status signals being queried on various video recorder models.

The interrupt input is used to evaluate control pulses that are accessible on various video recorders on externally attached connections.

125 The following connectors are attached to the basic device:

1 _• Additional chip select signals for additional peripherals

2. the IO control bus

3. part of the address bus for generating further chip select signals

130 4. the data bus

5. Modem signals of a second prepared serial channel on the basic computer system

In order to be able to control all video recorders available on the market, the following additional modules can alternatively be attached to the basic 135 computer system at the connectors:

A) A cassette interface is connected to the connector for the second serial channel, which in turn can be used to write data to an audio track of the video recorder and read it again.

140 B) An interface is connected to the connector for the second serial channel, which with a relatively high transmission speed transfers data into the blanking gap in a standard video signal can write and read again. In order to ensure a high transmission speed, the transmitter clock and the receiver clock are synchronized with the data to be transmitted. For this purpose, a clock generator is triggered by the interrupt signal derived from the line or picture synchronizing pulse.

By means of suitable programming of the basic computer system, positioning data are recorded on the video tape via A or B (formatting), which are then used for precise positioning.

The following also prove to be advantageous:

155 -seis for switching the video signal sources

Line and image synchronous signal processing and connection of these signals to further interrupt inputs

Subsequent formatting into the video track is possible without copying, by creating the synchronism through 160 the assemble editing device available in most video devices available today.

The procedure is:

1. PLAI and determination of the mean gray value

2. STILL IMAGE

165 3- RECORD

4. ASSEMBLE CUT and recording of a few pictures (eg 1 to 3) with the positioning data in the video signal in the determined blanking interval. The rest of the image content is given the previously determined gray value 170 wrote so that the visual impression is hardly disturbed later.

The following applications have proven to be favorable:

1. Interactive teaching systems

2. Systems for audio-visual management of documents

175 a) for general applications with normal standard video standards b) for replacing microfilms with increased resolution

3. for advertising purposes, e.g. At trade fairs, the trade fair staff can be relieved by interactively using the visitors

180 communicate the screen with the existing video material

4. for simulations

5.Archiving (e.g. in medicine for X-rays)

- as a cutting device

185 - Backup systems for data backup with directory

- Measured value acquisition (e.g. in meteorology)

- for the retrieval of pieces of music in the HIFI stereo video devices

- For synchronous synchronization of several video devices 190 for use as multi-track systems, as required

Traces can be bought

- As a supplement to a midi-controlled system for storing and retrieving real-time sounds.

Embodiments of the method of the invention for 195 format video tapes will now be explained with reference to the drawing voltages _¬. In these are: 1 is a schematic view of a video tape with formatting over the audio track,

2 shows the occurrence of a Seque ^' nz error,

3 a schematic representation of the formatting via the video track during the production of a video tape,

4 shows a schematic illustration of a subsequent formatting,

5 a schematic representation of a video tape provided with recordings with brightness measuring points arranged in a matrix and

FIG. 6 shows a hash code table belonging to FIG. 5.

1 illustrates the formatting of a video tape over 210 the audio track, the section t corresponding to the threading / unthreading time for the video tape 1 and the section t ^ to the time interval between the picture number signals 2 in the audio track. During the threading / unthreading time t, which is approximately 0.5 to 3 seconds, the audio signals cannot be read. It is therefore sufficient if the picture number signals are written at intervals of approximately 10 to 150 pictures. The section t, between the image number signals, which represents free space, so to speak, can be used for other data. The correct image number is determined during t _B 220 by counting the image pulses from the video track. The video information already represents formatting. The picture number signals in the audio track therefore only set the absolute picture counter reading.

If data security is to be increased, the image 225 num he can be distributed over several pictures. Here, however, as can be seen from FIG. 2, there is a risk that sequence errors will occur, since, for example, when transferring from ^' image pulse' 999 'to image pulse' 1000 ', the inscription' 1009 'can take place (see FIG. 2 ). To such a

To avoid 230 sequence errors, the current meter reading is only inserted into an auxiliary field at point A and is completely adopted as a picture number.

During the production of video tapes, i.e. when copying or recording, the formatting / positioning

235 via the video track. With conventional video tape devices, it is technically only possible to write complete video images. In the embodiment of the method according to the invention, as can be seen from the schematic illustration according to FIG. 3, the picture numbers are assumed

240 to write directly into the video signal, specifically in the respective blanking interval of the image synchronization pulses.

As FIG. 3 shows, a video signal S. coming from a video recorder (copying method) or from a video camera (recording method) is input directly and the respective image 245 synchronizing pulse I is input to a mixing part 4 via an image number generator 3, the output signal of which is sent to the video component signal S2 with picture number data correspondingly inscribed in the blanking intervals of the picture synchronizing pulses. The signal S2 is then recorded by a video recorder.

However, this method has the disadvantage that subsequent formatting by copying must always be carried out with two video recorders.

For subsequent formatting, as shown in FIG. 4, it has proven to be suitable to replace the original video images with gray images at greater intervals to write the average brightness of the previous images. The equation applies to the averaging process

.

where t ^ -t = original image period t _t -t, = gray scale image period

260 The image numbers are written into the blanking gaps of these gray images in accordance with the method described with reference to FIG. 3. In this embodiment of the method, the video images are destroyed at the points at which the image numbers have been inserted, and the resulting

A smooth transition, however, reduces the disadvantageous visual impression to a minimum.

If, however, the original video signal is not to be destroyed by the creation of gray images, a different route is chosen, namely that of the first one

270 images intended for formatting are read and stored in an image buffer. Then the predetermined location is sought again and the buffered images, in the blanking of which the image numbers in the above in connection with FIGS. 3 and 4-

275 have been inserted are written.

5 and 6 show a further embodiment of the method according to the invention for formatting video tapes, in which the video images (FIG. 5) are recognized via selected features, the contents of which as a hash code in a hash code. Code table (Fig. 6) can be saved under the corresponding image numbers. To the in 5 marked points 5, the brightness is measured, for example, when the entire video tape is read completely once. The corresponding measured values are used to construct the hash code table according to FIG. 6, which is stored on a vacant position on the video tape or on an external medium, such as a floppy disk. The stored hash codes are used for recognition and thus for determining the image number during the positioning process.

Claims

390 1. • Procedure for formatting video tapes via the video and / or audio track, in which picture number signals and other data are written on the video and / or audio track, characterized in that the picture number signals of the video and / or Audio track in time

2 5 intervals t-n are supplied and the range of

Video and / or audio track between the picture number signals is used for writing in the other data, the actual picture number during the time interval t- by counting the picture pulses from the

300 video track can be determined, while the frame number signals in the audio track only reflect the absolute frame count.

2. Procedure according to claim 1, characterized in that the time interval t "between the bidd number signals

305 approximately 10 to 150 images is selected accordingly.

3. The method according to claim 1 and 2, characterized in that the picture numbers corresponding to a picture number are distributed over several pictures.

4. A method for formatting video tapes on the 310 video path, characterized in that during a

Copying or recording the picture numbers are written directly into the blanking gaps of the video signal on the video track.

5- The method according to claim 4, characterized in that 315 the video signal from a video recorder or

-ka era direct and the blanking gaps of the video signal to be written image information about an image- number generator are fed to a mixer, the output signal of which is recorded by a video recorder intended for copying or recording, the picture numbers being written directly into the blanking gaps of the video signal.

6. The method according to claim 4 for subsequent Forma¬ tion, characterized in that in larger distances

3 5 the gray images are written in the place of the original video images with the average brightness of the previous video images and the blanking gaps of these gray images are supplied with the image numbers.

7. The method according to claim 6, characterized in that 330 first provided on the formatting

Images located in the location are read and temporarily stored in an image memory, so that the specified location is then sought again and the intermediate images are written back together with the image numbers in the 335 blanking intervals to the same location.

8. The method according to claim 7 _J, characterized in that approximately 1 to 5 images are read according to the location provided for formatting.

340 9. Method for formatting a video tape, characterized in that the video tape is first read completely, that suitable features such as brightness and the like are then calculated from the image signals at certain points and as a hash code in

345 of a table can be stored under corresponding picture numbers in such a way that the corresponding hash code from the abstracted images is constantly used to position the picture contents during playback of the video tape. characteristics, the table is then visited and the image number is returned.

10. The method according to claim 9, characterized in that the hash code table is stored at an unused location on the video tape.

11. The method according to claim 9, characterized in that the hash code table is stored externally on a floppy disk.