CZ9904077A3 - Device for record and reproduction and/or information arrangement in real time onto or from a record carrier - Google Patents

Abstract

Various measures are proposed to enable simultaneous reading and writing real-time information such as digital video a signal, z / to a disc type recorder (3). Measures represent the size requirement for information blocks recorded in fixed length fragments on carrier (3) record. In addition, measures for enabling are disclosed reproduction and continuous editing. Modification without interruption requires generating one or more junction blocks to be recorded on the record carrier (3) disk type.

Description

DEVICES FOR RECORDING AND REPRODUCING AND / OR EDITING INFORMATION IN REAL TIME TO A CARRIER OR FROM A RECORD CARRIER.

Technical field

The invention relates to a device for recording a real time information signal such as a digital video signal on a disc type record carrier, a device for modifying an information signal previously recorded on a disc type record carrier, related methods for recording / editing information, a reading device for reading information signal and record carrier. The record carrier may be of the magnetic or optical type. A device for recording a real time information signal, such as an MPEG video information signal, on a record carrier is known from USP 5,579,183 (PHN 14818). The record carrier herein is in longitudinal form.

BACKGROUND OF THE INVENTION

Disc type record carriers have the advantage of short access times. This makes it possible to perform "simultaneous recording and reproduction of the signal on / from the record carrier". During recording and reproduction, the information should be recorded on the record carrier / reproduced from the record carrier so that the real-time information signal can be recorded on the record carrier, and "simultaneously, the real-time information signal previously recorded on the record carrier can be reproduced without any interruption.

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SUMMARY OF THE INVENTION

It is an object of the present invention to provide measures to meet a variety of requirements, such as those set forth above. According to the invention, the real-time information signal recording apparatus, such as a digital information signal, comprises a disk-type recording medium, the data recording portion of which is further subdivided into fixed-size fragment regions:

input means for receiving the information signal signal processing means for processing the information signal into a channel signal for recording the channel signal onto a disc type recording medium write means for writing the channel signal to the record carrier, the signal processing means adapted to convert the information signal into blocks of channel signal information wherein the write is adapted to write the block of channel signal information into fragments on the record carrier, and wherein the signal processing is further adapted to convert the information signal into the block of information of the channel signal such that the size of the block of information may vary and satisfies the following relationship:

SFA / 2 <channel block size <SFA,

Where SFA is a fixed fragment size.

Further, a real time information signal conditioning apparatus, such as a digital video signal, recorded in a previous recording step on a disc type recording medium, the data recording portion of which is further divided into fixed length fragments, wherein the information signal is before recording

converted to a channel signal and then recorded on the record carrier such that the blocks of the channel signal information are recorded in the corresponding fragment regions on the record carrier, comprising:

input means for receiving an output position in a first information signal recorded on the record carrier and for receiving an input position in a second information signal, which may be a first information signal recorded on the record carrier, means for storing information related to the output and input positions; for generating at least one information splice block, the information splice block comprising information from at least one of the first and second information signals, which information is located before the output position of the first information signal and / or after the input position in the second information signal, and block of information can be variable and meets the following requirement:

SFA / 2 <link junction size <SFA, where SFA is equal to the fixed size of the fragment areas, write means for writing at least one information junction block in the corresponding fragment area, and means for reproducing the modified information stream from the record carrier.

Further, a device for reading a real time information signal, such as a digital information signal, from a disc type record carrier, wherein the information signal is recorded in the form of an encrypted channel in the data recording portion of the carrier.

recording, wherein the data recording portion is further subdivided into fixed-length fragments wherein the blocks of information of the encrypted channel information signal are recorded in corresponding fragments, the size of the blocks of information may be variable and satisfies the following relationship:

SFA / 2 <block size of channel signal information <

SFA, wherein SFA is a fixed fragment size, the device comprising:

means for reading the channel signal from the record carrier, signal processing means for processing blocks of variable length information and reading from the fragment areas into portions of the information signal, means for outputting the information signal.

The following advantageous embodiment is characterized in that the blocks of information in successive sequences alternately fulfill the following relations:

SFA / 2 <block size of channel signal <SFA and block size of specified channel = SFA.

This either leads to more efficient use of space or simplifies equipment requirements. Another preferred embodiment with the same advantages as the above is characterized in that the blocks of consecutive sequence information satisfy the following relationship:

2.SFA / 3 <channel signal block size <SFA.

· · * * * * * * * * * * * * * * * * * * * * * * * *

Overview of the drawings

The invention will be explained in more detail with reference to the drawings in which: FIG. 1 shows an embodiment of the apparatus; FIG. 2 shows fragmentation of information blocks into a record carrier; FIG. 3 shows the information video signal playback principle; Fig. 5 the principle of "simultaneous playback and recording, Fig. 6 situation during the modification when the linking block of information is not required to be generated or recorded. Fig. 7 an example of editing the information video signal and generating the linking block at the output position from the information signal. Fig. 8 is another example of adjusting the information video signal and generating the information link block at the same location of the output position as in Fig. 7;

an example of modifying an information video signal and generating a linking information block at an input position to an information signal, an example of modifying two information signals and generating a linking information block, an example of modifying two information signals and generating a linking block information, information signals, another embodiment of the device, a sequence of fragments showing three embodiments of the invention meeting the HF condition, the HFFF condition and the 2/3 condition, the general case of establishing a connection without moving the most unfavorable case of establishing a connection beyond

HFFF conditions together with Figures 16-21, showing several placement procedures in this case, the result of establishing a junction without moving in the local FF stream, together with Figures 23-24 illustrating several placement procedures in this case,

The 24A connection under 2/3 conditions containing only MPEG data, together with FIGS. 24B-36, illustrates several placement procedures in this case.

DETAILED DESCRIPTION OF THE INVENTION

Giant. 1 shows an embodiment of the device according to the invention. In the following description of the figures, attention will be focused on recording, reproducing and adjusting the information video signal. Of course, it should be borne in mind that other types of signals, such as audio signals or data signals, can be processed as well.

The apparatus comprises an input terminal 11 for receiving an information video signal for recording on a disc type recording medium 3. Further, the apparatus comprises an output terminal 2 for supplying an information video signal reproduced from the record carrier 3. The record carrier 3 is. magnetic or optical disk type.

The data area of the disc type record carrier 3 consists of a continuous series of physical sectors having corresponding sector addresses. This address space is divided into fragments. The fragment is a continuous sequence of fixed-length sectors. Preferably, this length corresponds to an integer number of ECC blocks included in the information image signal to be recorded.

The apparatus shown in Fig. 1 is shown divided into two main system parts, namely the disk subsystem 6 and the so-called "video recorder subsystem". The following characteristics characterize the two subsystems:

The disk subsystem can be addressed transparently in terms of logical addresses. It controls autonomously the operation of defects • · · ······································ · (Including mapping logical addresses to physical addresses).

-For real-time data, the disk subsystem is addressed based on the fragment relationship. For data addressed in this way, the disk subsystem can guarantee a maximum sustainable bitstream of read and / or write. In the case of concurrent read / write, the disk subsystem handles read / write scheduling and associated caching from independent read and write channels.

For non-real-time data, the disk subsystem can be addressed on a sector-by-sector basis. For the data addressed in this way, the disk subsystem cannot guarantee any acceptable read / write bitstream.

-the VCR system handles the application of the image as well as file system management. Therefore, the disk subsystem does not interpret any data that is recorded in the disk's data area.

In order to realize real-time reproduction in all situations, the fragments described above need a certain length. Also, in a situation where recording and reproduction takes place simultaneously, reproduction should not be interrupted. In this case, the fragment size is selected to meet the following requirement:

fragment size = 4 MB = ^{22 22} bytes.

At this point, the recording of the video information signal with reference to FIG. 2 will be briefly explained. In the VCR subsystem, the video information signal, which is a real time signal, is converted to real time as shown in FIG. 2a.

file

The real-time file consists of a sequence of signal blocks of information recorded in the corresponding fragments.

··· · t · · ··· ·· ··

There is no restriction on the location of the fragments on the disc and thus two consecutive fragments containing portions of the information of the recorded information signal may be anywhere in the logical address space as shown in Fig. 2b. Within each fragment, real-time data is placed continuously. Each file represents one AV stream in real time. The data of this AV stream is obtained by concatenating the data from the fragments in the sequence in the file.

Next, the playback of the information video signal recorded on the record carrier will be briefly explained with reference to Fig. 3. The playback of the information video signal recorded on the record carrier is controlled by a so-called "playback control program (PBC program)". Generally, each PBC program defines a (new) playback sequence. This is a sequence of fragments where, for each fragment, the data segment to be read within that fragment is specified. In this regard, reference is made to Fig. 3, where playback is shown by only a portion of the first three fragments in the sequence of fragments in Fig. 3. The segment can be the entire fragment, but generally will be only a portion of the fragment. (The second case usually occurs when moving from one part of the original record to another part of the same or another record as a result of an edit.)

Note that simple linear playback of the original record can be considered a special case of a PBC program: in this case, the playback sequence is determined as a sequence of fragments in the file in real time, where each segment is a complete fragment, probably excluding the segment in the last fragment of the file. For fragments in the playback sequence, there is no restriction on the location of the fragments, and therefore any two consecutive fragments. · Fragments can be anywhere in the logical address space.

Next, the modification of one or more information video signals recorded on the record carrier will be briefly explained herein. Giant. 4 shows two information video signals previously recorded on record carrier 3, represented by two sequences of fragments called "file A and" file B. To create a modified version of one or more information video signals recorded earlier, a new PBC program needs to be created to define the modified AV sequence. This new PBC program thus defines a new AV sequence obtained by concatenating portions from earlier AV records in a new order. These parts can be from a single record or from multiple records. In order to play a PBC program, data from different parts (one or more) of the programs must be moved to the decoder in real time. The result is a new stream of data obtained by concatenating real-time portions of the streams represented by each file. In Fig. 4 this is shown for a PBC program that uses three parts, one from set A and two from set B.

Giant. 4 shows that the modified version starts at Pi in fragment f (i) in the sequence of fragments of set A and continues up to P ₂ in the new fragment f (i + 1) of set A. Then the reproduction jumps to P ₃ in fragment f (j) in file B and continues to point P ₄ in fragment f (j +2) in file B, file B,

Further, the reproduction jumps to the point P5 in the same which can be found both in the sequence of fragments of file B by the point before the point P ₃ and in the sequence by the point after the point P ₄ .

Next we will deal with the condition of playback under simultaneous recording.

for uninterrupted Generally it can

uninterrupted playback of PBC programs only under certain conditions. The strictest condition is required to guarantee continuous playback when recording is in progress. One simple condition will be given for this purpose. It is a limitation of the length of the data slices that are present in the playback sequences as follows:

MB w segment length w 4 MB.

The use of fragments allows us to consider the most unfavorable case of performance claims only with respect to fragments and segments (signal blocks stored in fragments), as will now be described. This is based on the fact that the individual regions of the logical fragments, and hence the data segments within the fragments, are certainly physically linked to each other even after remapping due to defects. Of course, there is no such guarantee between fragments: logically, the following fragments can be as far apart as possible on the disk. Consequently, we will focus on the following analysis of performance requirements:

a) For playback, the data stream read from the sequence of segments on the disc is considered. Each segment is contiguous and has any length between 2 MB and 4 MB, but the segments are distributed arbitrarily on the disk.

(b) The data stream to be written to the disk into a sequence of 4 MB fragments shall be considered for recording. The fragments are freely placed on the disk.

Note that for playback, the length of the segments varies. This corresponds to the condition for segments for uninterrupted playback during simultaneous recording. Odpovídá · segment při při při při při při při při při při při při při při při při při Of course, complete fixed-length segments are recorded.

With a specified data stream for recording and playback, we can focus on the disk subsystem during simultaneous recording and playback. It is assumed that the video recorder subsystem provides the sequence of segment addresses for both the recording stream and the playback stream well in advance. For simultaneous recording and playback, the disk subsystem must be able to interleave read / write alternate so that the recording and playback channel can provide continuous performance at the highest speed without causing the buffer to overflow or underflow. This can generally be achieved by various R / W scheduling algorithms. There are, of course, strong reasons to do planning so that the R / W cycle time at the highest speeds is as short as possible:

- Shorter cycle times lead to smaller cache sizes for the read / write cache and hence for the overall memory of the subsystem.

-Shorter cycle times lead to shorter response times to user steps. As an example of the response time, consider a user performing simultaneous recording and playback and suddenly want to start playing from a new position. In order to keep the total response time of the device (visible on the user's screen) as short as possible, it is important that the disk subsystem is able to start sending data from the new position as quickly as possible. Of course, this must be done so that once the data starts to flow, the highest continuous playback speed is guaranteed. Writing must also be without interruption with guaranteed quality.

For this analysis, a planned cycle-based approach is assumed in which one entire fragment is written. To analyze the following features of a disk drive, it is sufficient to consider the minimum cycle time under the most unfavorable conditions. Such the most unfavorable cycle consists of a write interval where a 4 MB segment is written and a read interval where at least 4 MB are read spread out over one or more segments. The cycle contains at least two jumps (to and from the write position), but probably more, because the read segment lengths are variable and may be less than 4 MB. This can lead to further jumps from one read segment to another. Since the read segments cannot be less than 2 MB, of course no more than two additional jumps are needed to get a total of 4MB. Thus, the most unfavorable R / W cycle has a total of four jumps, as shown in Fig. 5. In this figure, x is the last segment of the read segment, y is the complete segment read between 2 MB and 4 MB, and z. and the total size x <y and z in this example is 4 MB again.

In general, the disk drive parameters required to achieve guaranteed simultaneous recording and playback performance are dependent on basic execution decisions such as rotation mode, etc. These decisions in turn depend on the characteristics of the medium.

The above conditions for continuous playback during simultaneous recording are derived to correspond to various embodiments with attainable parameters. To illustrate this, we show an example of a CLV (constant linear velocity) unit.

In the case of the CLV, the read / write bit rates are the same and independent of the physical location on the disc. Thus, the most unfavorable case described above may be

analyzed with respect to just two unit parameters: the baud rate R and the most unfavorable total access time i. This time includes disk acceleration / deceleration, rotational latency, possible repetitive accesses etc., but not processing delays, etc.

For the most unfavorable cycle of a part, all jumps can be of duration τ. This gives the most unfavorable cycle time:

described in the previous worst jumps following expression for

Tmax 2F / Rt + 4.1, where F is the fragment size: F = 4 MB = 33.6.10® bits In order to guarantee acceptable performance at the highest user speed R, the following should be met:

So further:

RF / _Tmax = Rt.F / 2. (F + 2R _t- T)

For example, for R _t = 35 Mbps and τ = 500 ms, we should: R <8.57 Mbps.

The modification will be described in more detail below. Generating a new PBC program or modifying an existing PBC program will generally result in a new playback sequence. The aim is to ensure that the result can be played back continuously under any circumstances, even during simultaneous recording. We will analyze a series of examples where we assume that the user's interest is to create a new A V stream from one or two existing AV streams. Examples will be discussed for two streams called A and B, where the user intends to create a transition from A to B. This is illustrated in Figure 6, where a is the intended exit point from stream A and b is the intended entry point into stream B.

Giant. Fig. 6a shows the sequence of fragments ......, f (i-1), f (i), f (i + 1), f (i + 2), .... of stream A, and Fig. 6b shows the sequence of fragments ....... f (j-1), f (j), f (j + 1), f (j + 2),

.... stream B. The edited information video signal consists of a portion of stream A preceding the output point a in fragment f (i + 1) and a portion of stream B beginning at the input point b in fragment f (j).

This is a general case that covers all cut-paste modifications, including the connection of two streams, etc. It also includes the special case where A and B are identical. Depending on the mutual placement of a and b, this particular case corresponds to effects in the PBC such as skipping a partial flow or repeating a partial flow.

The analysis of the examples focuses on achieving uninterrupted playability during simultaneous recording. The condition for uninterrupted playability is the segment length condition of the length of the blocks of the information signal stored in the fragments, as described previously. It will further be shown that if the streams A and B satisfy the condition for the length of the segments, then the new stream may be defined to also satisfy the condition for the length of the segments. Thus, uninterrupted play streams can be modified to new uninterrupted play streams. And since the original records are recorded to be playable continuously, this means that any edited stream will be playable continuously. The result is the possibility of arbitrary • 4 · 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 · Adjustments to previously treated streams. Therefore, we do not need streams A and B to be the original records in our analysis: they can be arbitrary results of earlier actual adjustment steps.

In the first example, a simplified assumption will be made about the AV coding format and the selection of input and output points. It is assumed that points a and b are from the viewpoint of the AV coding format such that a direct transition can be formed. In other words, it is assumed that direct concatenation of data from stream A (ending at exit point a) and data from stream B (beginning at entry point b) will result in a valid stream when considering the AV encoding format.

It follows from the foregoing assumption that a new playback sequence can basically be defined based on existing segments. However, for uninterrupted playability, it is necessary to ensure that all segments meet the segment length condition at the transition point from A to B. Let's focus on flow A and see how we do this. Consider a fragment of stream A that contains an exit point a. Let s be a segment in this fragment ending at a, see Figure 6a.

If l (s), length s, is at least 2 MB, then this segment can be used in the new playback sequence and point a is the exit point that should be stored in the PBC program.

However, if l (s) is less than 2 MB, the resulting segment s does not satisfy the segment length condition. This is shown in FIG. 7. In this case, a new fragment f, the so-called linking fragment, is produced. In this fragment, there is a connecting segment containing a copy of s, preceded by a copy of some previous data from stream A. For this, consider the original segment r preceding the segment s in stream A, as shown in Fig. 7a. Now, depending on the length r of the segment stored in fragment f (i), either all or part of r is copied to the new fragment f:

If l (r) + l (s) ø 4 MB, then the entire r is copied to f and the original segment r is not used in the new playback sequence, as shown in Figure 7a. In more detail, the new exit point is designated ^z and this new exit point and ^z is stored in the PBC program, and further, upon completion of the editing step, recorded on the disc type record carrier. Thus, in response to this PBC program during playback of the edited image information stream after reading the information stored in the fragment f (i-1), the program jumps to the link fragment f ^z to reproduce the information stored in the link fragment f and then jumps to the entry point of the video stream. B for reproducing part of flow B as shown schematically in FIG. 7b.

If l (r) + l (s)> 4 MB, then a portion of p from the end of r is copied to f_y, where the length of p is such that:

MB <1 (p) - 1 (p) <4 MB ^Λ 2 MB <1 (p) + 1 (p) <4 MB

Reference is made to Fig. 8, where Fig. 8a shows the original stream A and Fig. 8b shows the modified stream A with the splice fragment f '. In the new playback sequence, only the smaller segment r ^z is used in the fragment f (i) containing r. This new segment r 'is a sub-segment r, namely the first part r with the length l (r') = l (r) - l (p). We also need a new exit point a 'to jump to the junction fragment f', indicating the position where the original flow A is to be abandoned. This new exit point should therefore be stored in the PBC • · »··» ··· ·· » * * · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · ·

In the above example, it was discussed how to create a junction segment (or junction block of information) for fragment f 'if the last segment of stream A (i.e., £) becomes too short. Now let's focus on the flow Β. In flow B there is a similar case for a segment that contains an entry point b, see Fig. 9. 9a shows the original stream B and FIG. 9b the modified stream. Let t be a segment containing an entry point b. If t becomes too short, a junction segment 6 may be formed for retention in the corresponding junction fragment. By analogy to the case of the splice fragment f ', £ will consist of a copy of t and a copy of some other data from stream B. This data is obtained from the original segment u that follows t in the fragment f (j +1) in stream Β. Depending on the length u, either part or the entire u is copied to £. This is analogous to the case for r described in the previous example. The various cases will not be discussed in detail here, but Fig. 9b gives an idea by showing an analogy to Fig. 8, where u is divided into v and u. The result is a new entry point b 'in stream B to be stored in the PBC program and later on the record carrier.

Another example, described in FIG. 10, shows how a new, continuously playable sequence can be defined under all circumstances by creating at most two linking fragments (f ^z and δ). It can be shown that in fact one linking fragment is sufficient even if it is too short. This is achieved if it is copied into one link fragment (and if necessary any previous data from stream A and / or any subsequent data from stream B). We will not be much concerned with this, but Figure 10 shows a general result.

In the previous examples, it was assumed that concatenation of the data stream at the output and input points a and b is sufficient to produce a valid A V stream. In general, however, some coding must take place before a valid AV stream can be created. This typically occurs when the output and input points are not GOP boundaries when the encoded information video signal is encoded as an MPEG information video signal. Re-encoding will not be described here, but generally will result in some connection sequences to transition from stream A to stream Β. As a result, a new exit point a 'and a new entry point b' will be created and the junction sequence will contain recoded data corresponding to the original pictures from a / _ to and followed by the original pictures from b to b '.

All cases the overall result is not described in detail here, but as in the previous cases: there will be one or two junction fragments to cover the transition from A to B. Unlike the previous examples, the data in junction fragments is a combination of recoded data and some data copied from the original segments . Giant. 11 allows to create a general idea.

Finally, note that we do not have to have any special restrictions on recoded data. The re-encoded stream must simply meet the same bit rate requirements as the original data stream.

Giant. 12 is a more detailed diagram of the apparatus. The apparatus includes a signal processing unit 100 that is included in the subsystem 8 of Fig. 1. The signal conditioning unit 100 receives an input video signal of an input image 9 &lt; tb &gt; 9 · a · 0 * 9 * 9 4

9 9 * 9 9 * 99 0 9 0 * terminal 1 and processes the video information into a channel signal for recording the channel signal on the disc type record carrier 3. Further, there is a read / write unit 102 that is included in the disk subsystem 6. The read / write unit 102 includes a read / write head 104, which in our case is an optical read / write head for reading / writing the channel signal to / from the carrier 2 record. Further, adjusting means 106 are provided for aligning the head 104 in the radial direction above the record carrier 3. The read / write amplifier 108 is present to amplify the signal to be written and to amplify the signal read from the record carrier 3. The motor 110 is provided for rotating the record carrier 3 in response to a motor control signal supplied by the motor control signal generation unit 112. The microprocessor 114 is present for controlling all circuits through control lines 116, 118 and 120.

The signal processing means 110 is adapted to convert video information received by the input terminal 11 into blocks of channel signal information of a certain size. The size of the blocks of information (which is the above segment) may be variable, but the size is such that it satisfies the following relationship:

The SFA / 25 block size of the SFA channel signal, where SFA is equal to the fixed fragment size. In the above example, SFA = 4 MB. The write unit 102 is adapted to write a block of channel signal information into a fragment on the record carrier.

To provide adjustment of the image information recorded in the previous step to the record carrier 3, the apparatus is further provided with an input unit 130 for receiving an output position in the first information image signal recorded on the record carrier and receiving an input position in the second information image signal recorded on the same record carrier. . The second information signal may be the same as the first information signal. Further, the device includes a memory 132 for storing information regarding exit and entry points. Further, the apparatus includes a splice block generation unit 134 included in the signal conditioning unit 100 to generate at least one splice block of information (or splice segment) of a certain size. As explained above, the information splice block comprises information from at least one of the first and second information video signals, which information is located upstream of the output position in the first information video signal and / or after the input position in the second information video signal. As described above, during the adjustment, one or more link segments are generated in the unit 134 and in the edit step, one or more link segments are recorded on the record carrier 3 in the corresponding fragment. The size of the at least one linker also satisfies the relationship:

SFA / 2 d junction block size d SFA.

Further, the PBC programs obtained by the conditioning step may be stored in a memory embedded in the microprocessor 114, or in other memory embedded in the device. The PBC program created in the edit step for the modified information video signal is recorded on the record carrier after the edit step. In this way, the edited information video signal may be reproduced by another reproducing device by reading the PBC program from the record carrier and playing the edited information video signal. · · · · · · · · · · ^Ř · · · Using a PBC program corresponding to the modified information signal.

In this way, a modified version can be obtained without having to re-record portions of the first and / or second information video signal, but simply by generating and recording one or more link segments into corresponding (link) fragments on the record carrier.

In the embodiment described above, the fragments produced on the disk are at least half full. This will be called the HF condition, while the fragment will be called FF when fully filled. As shown above, after adjusting the stream meeting the HF condition, it is possible to ensure that the resulting stream also satisfies the HF condition. This requires reserving one fragment as a linker. In the most unfavorable case, the A / V result may be a stream consisting exclusively of half-empty fragments. Giant. 13A schematically illustrates such a sequence of half-empty HF fragments. This flow imposes stringent disk drive performance requirements.

Next, the second and third embodiments for recording and editing video / audio streams on a disc will be described. These embodiments simplify the most unfavorable situation with respect to occupying a space that may occur in the first embodiment, as shown in Fig. 13A. The most unfavorable case of fragment flow resulting from the second embodiment is shown in Fig. 13B. This stream satisfies the HFFF condition requiring at least every second fragment to be fully filled. The most unfavorable case of fragment flow resulting from the third embodiment is shown in Fig. 13C. Note that the second and third embodiments also reduce the device requirements. This current satisfies the condition 2 / 3F, which results in a minimal fragmentation greater than 2 / 3. Although this case will be considered in more detail, other fill values are also possible.

It will be shown that more than one fragment may be needed for splicing to achieve one of these conditions. A first connection is considered if the first embodiment satisfies the HF condition. Giant. 14 shows a general case of establishing a connection, the details of which have already been discussed herein. Note that the fragments before and after the join may have originally been full fragments, but as a result, selecting the edit points in the modified sequence will be partially filled. The only assumption is that the pre-splice, splice fragment, and post-splice fragments are at least half-filled.

Next, it will be shown how to establish a connection in the case of a second embodiment meeting the HFFF condition. Giant. 15 shows a modified sequence showing the most unfavorable case in this case. In the original sequences, both the last fragment before the junction and the first fragment after the junction must be full, since it is assumed that the original flows meet the FFHF condition. First, it is attempted to maintain the FFHF condition by moving the fragment before splicing, splicing fragment and fragment after splicing (relocation of three fragments). Generally, the following assumption can be made about the size of these fragments:

1.5 <size (3 * HF) <3 [1], where the units are fragment sizes. This condition implies the following variants of repositioning the three fragments:

- 24 - • ·· · · ···· «· · · · · · • · · · • · · · · · ··· 1.5 <size (3 * HF) <2 [2] 2 < size (3 * HF). <2.5 [3] 2.5 <size (3 * HF) <3 [4]

Option [1] can be moved as FF + HF, [2] as FF + HF + FF and [3] as FF + FF + HF. In the latter case, by relocating the three fragments such as FF, HF and FF, the FFHF condition can be maintained. However, as a result, the junction requires three fragments instead of one, as shown in Figure 16. In other cases, it is not possible to maintain the FFHF condition by relocating the three fragments. Thus, summarizing [1] and [2], we get the following condition:

1.5 <size (3 * HF) <2.5 [5]

By adding the fourth HF fragment (displacement of the four fragments), this condition becomes:

<size (4 * HF) <3.5 [6]

This condition results in the following relocation variants of the four fragments:

= size (4 * HF) [7] <size (4 * HF) <2.5 [8]

2.5 <size (4 * HF) <3 [9] <size (4 * HF) <3.5 [10]

Option [7] can be moved as FF + HF, [8] as • * ·· · · · · · · · · · · · · · · · · ·

FF + HF + HF, [9] as FF + FF + HF and [10] as FF + FF + HF + HF. In the latter case [8] it is not possible to fulfill the FFHF condition. The third case [9] is shown in Fig. 17. The fourth case [8] requires four fragments to join and is shown in Fig. 18. However, the variant [8] shows that the first fragment can be 0.5 and still ensure that FF segments can be filled. But that means we can only take the first half of the original HF fragment. This gives us a three-fragment connection, as shown in Figure 18.

In another variant [8] in which it was not possible to relocate, a fifth HF fragment is added:

2.5 <size (5 * HF) <3.5 [11]

This variant results in the following variants of repositioning the five fragments:

2.5 <size (5 * HF) <3 [12] <size (4 * HF) 3.5 [13]

In both cases, it is possible to reposition five fragments to meet the HFFF condition. Giant. 19 shows the first case [12] requiring three fragments, while FIG. 20 shows the second case [13] requiring four fragments. Of course, as above, variant [13] suggests that the first HF fragment may be 0.5 and still be guaranteed that the FF fragments will be filled. But this means that only the first half of the segment of the original HF fragment can be taken. The result is a three-fragment linkage, as shown in FIG. 21. In conclusion, it is possible to meet the HFFF condition with the most unfavorable linkage of the three fragments. Since this condition is weaker than the FF condition, the previous analysis also includes the adjustment of FF flows. In most cases, the edited streams will be local in nature to the FF unless the user makes very close adjustments. The case of modifying the local FF flow should be better than the worst case described above. The general case of flux adjustment that satisfies the FF condition is shown in Fig. 22. Considering the three HF fragments, the following condition applies:

1.5 size (3 * HF) b 3 [14]

This condition implies the following variants of relocating three fragments:

1.5 <size (3 * HF) <2 b size (3 * HF) b 3 [15] [16]

Variant [15] can be relocated as FF + HF and [16] as FF + HF + HF. In the first case [15], it is possible to reposition three fragments as two fragments, as shown in Fig. 23. Note that it is generally not possible to use one FF fragment to join and retain one of the original HF fragments. In the latter case [16] it is possible to use one fragment per junction. Data can be copied from the other two fragments until the linker is FF-like. This makes it possible to satisfy the HFFF condition with a single linker fragment. This is shown in Figure 24.

Finally, note that the worst case only occurs when the user makes many close adjustments. Normally, where the adjustments are several seconds apart, the join will require no more than two fragments. Aforesaid

analyzing the second embodiment for the most unfavorable case, possibly with a detailed analysis of the first embodiment, will enable one skilled in the art to use linking either software or hardware, or both software and hardware for all cases.

Note that replacing the HF condition in the first embodiment with the HFFF condition will result in a longer connection and thus the actual modification requires more disk space than with the HF condition. Of course, in the case of actual modifications where the original stream can be deleted and only the modified stream is left on the disk, the second embodiment actually saves disk space. In many cases, a group of partially filled fragments will be moved to fewer fragments.

Next, a third embodiment satisfying the 2/3 condition will be discussed. Note that in general, the more fragment we require, the more fragments we need to make a connection. For example, the HF condition may be replaced by one where the smallest fragment fill would be 0.75, i. each at least partially filled PF fragment meets:

0.75 size (PF) <1 [17]

This gives the same average fragment loading in the worst case as the FFHF condition of 0.75. In order to maintain the 0.75 condition, we need in the worst case a connection of four fragments, even if the original flow of the character is FF. Thus, this option is not as good as the HFFF condition described above. The 2 / 3F condition in the worst case gives a lower average fragment fill than the HFFF condition and at the same time we can expect fewer shifts than under the HFFF condition. Giant. 24 shows the starting point for making connections, provided that the original streams meet the 2 / 3F condition. Here, D means a portion of an MPEG connection, that is, a portion of the streams that must be copied, re-encoded or remultiplexed to meet the MPEG requirements. No assumption can be made to fill the fragment directly preceding the junction or the fragment directly after the junction, since the filling of these fragments will depend on the selection of adjustment points. Many cases will be considered based on the filling of fragments before and after joining.

Giant. 25 illustrates case 1. Here, both the fragment before the join and the fragment after the join are filled with more than 2/3, and the join contains only the data required to meet the MPEG requirements.

If

B1 + D + B2> 2/3 [18] then there is no problem and the result is shown in Fig. 26.

If

B1 + D + B2> 1 [19] then the entire B1 and B2 will not be copied.

If

2/3 + B1 + D <1 [20] or ·· ··· «· · <

2/3 + B2 + D <1 '21' then there is no problem and the result is shown in Fig. 27 and Fig. 28 respectively.

Assuming that 0 <B1 + D + B2 <2/3 and adding the contents of the other two fragments gives:

4/3 <2/3 + Bl + D + B2 + 2/3 <6/3 [22]

In this case, it is possible to move data in at least 2/3 of the fragments, as shown in Fig. 29. Whether the original stream was locally FF or not has no effect on the outcome of this case.

Giant. 30 shows the starting point for case 2. Here both the pre-join fragment and the post-join fragment are less than 2/3 full. If

2/3 <Bl + D + B2 <1 [23] is not a problem and the result is shown in Fig. 31. Now we have to assess two situations:

Bl + D + b2 [2/3]

Bl + D + B2> 1

We will first discuss the situation [24]. Adding all or parts of C1 and C2 to create a 2/3 fragment still presents problems if C1 + C2 does not carry enough data. This occurs under the following conditions:

Cl + B1 + D + B2 + C2 <2/3

By adding the rest we will get: previous a following fragment [27] 4/3 < 2/3 + Cl + B1 + D + B2 + C2 + 2/3 <6/3 This data they can be relocated like two fragments as FIG . 32.

We will now discuss the situation [25]. This will only cause problems if:

<B1 + D + B2 + <4/3 [28]

Again, part or all of Cl and C2 can be added to get a total of at least 4/3, and the problem occurs if:

<Cl + B1 + D + B2 + C2 <4/3 [29]

In this case, adding the preceding or following fragment gives:

5/3 <2/3 + Cl + B1 + D + B2 + C2 <6/3 [30]

Data in this case can be placed as two fragments, as shown in Figure 10.

If the original stream was FF locally, then Cl = 1/3 and C2 = 1/3 and in the first situation [24] one fragment is sufficient to join. In the second situation [25], we still need two fragments to join.

Giant. 34 shows the starting point for case 3. Here, the fragment prior to joining is less than 2/3 filled and the fragment after joining is more than 2/3 filled. If

2/3 <B1 + D + B2 [34] a

B1 + D <1 [35] then there is no problem and we can use one fragment for connection.

I consider these two cases:

B1 + D + B2 <2/3 [36] a

<B1 + D <4/3 [37]

Now in the first case [36] by adding the rest of the fragment after the connection we get:

2/3 <B1 + D + B2 + 2/3 <4/3 [38]

The problem occurs if:

<B1 + D + B2 + 2/3 <4/3 [39]

Part or all of C1 and C2 may be added to ensure that

data can fill two fragments, so the problem still persists if:

<Cl + B1 + D + B2 + 2/3 + C2 <4/3 [40]

Adding the remainder of the previous or next fragment gives:

5/3 <2/3 + Cl + Bl + D + B2 + 2/3 + C2 <6/3 [41]

This data can be transferred to two fragments, as shown in Figure 35.

Let us consider the second case [37]. Adding B2 is possible, but the problem still persists if:

<Bl + D + B2 <4/3 [42]

Adding the rest of the fragment after the join yields:

5/3 <Bl + D + B2 + 2/3 <6/3 [43]

This data can be moved to two fragments, as shown in Figure 36. The connection will still require two fragments even though the original stream was locally FF.

From this we conclude that it is possible to replace the HF condition with a condition where the minimum fragment fill is 2/3 of the full fragment. This requires at most two fragments per junction. Adjusting a stream that has a local FF character will still in some cases require two fragments to join.

While the invention has been described with respect to preferred embodiments, it is to be understood that these are not limiting examples. Thus, those skilled in the art can attack many variations without departing from the scope of the invention as defined in the claims. The published 4 MB fragment size is characteristic of one particular embodiment. Other embodiments may use other fragment sizes, such as 6 MB. It should further be noted in this sense that the first generation devices of the invention capable of real time recording and playback of the information signal may be able to record fixed-length SFA signal blocks only in fragments while already capable of reproducing and processing the signal blocks variable lengths from the fragments in an attempt to reproduce the information signal in real time from a record carrier having blocks of variable-length signals stored in the fragments. In addition, second generation devices capable of performing the conditioning step will be able to record blocks of variable length signal into fragments.

Further, the invention resides in each and every new feature or combination of features. The invention may be implemented in both hardware and software, and these several means may represent the same hardware item. Furthermore, the term "comprises does not exclude the presence of elements or steps other than those set forth in the claims.

Represented by:

Dr. Pavel Zelený v.r.

JUDr. Pavel Zeleny advokat

120 00 Prague 2, Halkova 2

Claims (35)

PATENT CLAIMS A device for recording a real time information signal, such as a digital video signal, on a disc type recording medium, the data recording portion of which is further divided into fixed size fragments, characterized in that the device comprises: input means for receiving the information signal signal processing means for processing the information signal into a channel signal for recording the channel signal on a disc-type record carrier recording means for writing the channel signal to the record carrier, the signal processing means being adapted to convert the information signal into blocks channel signal information, wherein the write is adapted to write a block of channel signal information into fragments on the record carrier, and wherein the signal processing is further adapted to convert the information signal into blocks information channel the signal make the blocks size information could be variable and fulfilled the following relationship: SFA / 2 <size block channel signal <SFA, Where SFA is equal to the fixed fragment size. The apparatus of claim 1, wherein the signal processing means is adapted to convert the information signal into blocks of information 09 78 807 of a channel signal such that successive sequence information blocks alternately meet the following relationships: SFA / 2 <channel signal block size S SFA channel signal block size = SFA. The apparatus of claim 1, wherein the signal processing means is adapted to convert the information signal into information channel blocks of a channel signal such that successive sequence information blocks satisfy the following relationship: 2.SFA / 3 velikost block size of channel signal S SFA. 4. A device for modifying a real-time information signal, such as a digital video signal, recorded in a previous recording step on a disc type recording medium, characterized in that its data recording portion is subdivided into fixed-length fragments, wherein the information signal is prior to recording, converted to a channel signal and then recorded on the record carrier such that the blocks of channel signal information are recorded in corresponding fragments on the record carrier, the apparatus comprising: input means for receiving an output position in a first information signal recorded on the record carrier and for receiving an input position in a second information signal, which may be the first information signal recorded on the record carrier, - means for storing information concerning the exit and entry positions, means for generating a junction block for generating at least one junction information block, the junction block containing information from at least one of the first and second information signals, said information being located upstream of the first information signal and / or downstream of the input position of the information signal; a second information signal and wherein the size of the information junction block may be variable and meet the requirement of: SFA / 2 <link junction size <SFA, where SFA is equal to fixed fragment size, - write means for writing at least one linking block of information to the corresponding fragment, and means for reproducing the modified information stream from the record carrier. The apparatus of claim 4, wherein the splice block generating means is adapted to generate a successive sequence of a maximum of three splice blocks of information alternately meeting the following relationships: SFA / 2 velikost block size of channel signal S SFA a channel block block size = SFA. 6. The apparatus of claim 4, wherein the coupling block generating means is adapted to generate a successive sequence of a maximum of two switching blocks of information alternately meeting the following relationship: 2.SFA / 3 <block size of channel signal FA SFA. Device according to claim 1 or 4, characterized in that the SFA is equal to 4 MB. The apparatus of claim 4, wherein if the amount of information in the first fragment of the first information signal that includes the output position from the beginning of the block of information in that fragment to the output position is less than SFA / 2, then the means for generating the link and at least the last piece of information stored in the second fragment directly in front of the first fragment in the first information signal so as to achieve a linking block size information requirement. The apparatus of claim 8, wherein the remaining information stored in the second fragment meets the requirement of: The size of the remaining portion of the information in the second fragment SFA, and that the boundary between the remaining portion of the information and the last portion of the information in the second fragment is a new output position from the first information signal when the modified information stream is reproduced on the device; means for storing information regarding the new exit position. The apparatus of claim 4, wherein if the amount of information in the first fragment of the first information signal that includes the output position from the beginning of the block of information in that fragment to the output position is less than SFA / 2, then the means for generating the link block adapted to generate a junction block of information from the information in the first fragment before the output position and the information stored in the second fragment directly before the first fragment in the first information signal. The apparatus of claim 10, wherein the last location of the signal block in the third fragment directly before the second fragment in the first information signal is a new output position from the first information signal when a modified information stream is reproduced on the device, the device further comprising means. to store information regarding the new exit position. The apparatus of claim 4, wherein if the amount of information in the first fragment of the second information signal that includes the input position from the input position to the end of the block of information in that fragment is less than SFA / 2, then the means for generating the block being adapted to generate a junction block of information from the information in the first fragment after the input position and at least the preamble of the information stored in the second fragment directly after the first fragment in the second information signal so as to achieve the junction block size information. · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · The apparatus of claim 12, wherein the remaining information stored in the second fragment satisfies the relationship: SFA / 2 <the size of the rest of the information in the second fragment A of the SFA, and that the boundary between the rest of the information and the preamble of the information in the second fragment is the new input position to the second information signal when the modified information stream is reproduced on the device. means for storing information regarding the new entry position. The apparatus of claim 4, wherein if the amount of information in the first fragment of the second information signal that includes the input position from the input position to the end of the block of information in that fragment is less than SFA / 2, then the means for generating a block adapted to generate a junction block of information from the information in the first fragment after the input position and the information stored in the second fragment directly after the first fragment in the second information signal. The apparatus of claim 14, wherein the initial position of the signal block in the third fragment directly after the second fragment in the second information signal is a new input position to the second information channel when the modified information stream is reproduced on the device, the apparatus further comprising means. to store information regarding the new start position. 16. The apparatus of claim 4, wherein if the amount of information in the first fragment of the first information signal that includes the output position from the beginning of the block of information in that fragment to the output position is less than SFA / 2, then the means for generating a block adapted to generate a junction block of information from the information in the first fragment upstream of the exit position and at least a portion of the information stored in the second fragment of the second information signal including the input position, a portion extending from the entry point in the direction of the final position of the second fragment to the size of the junction block of information. 17. The apparatus of claim 16, wherein the junction block of information includes information in the first fragment upstream of the output position and only a portion of the information from the second fragment so as to also achieve a size requirement of the information in the second fragment after the portion stored in the junction block. . The apparatus of claim 16 or 17, wherein the end position of the signal block contained in the third fragment directly before the first fragment in the first information signal is a new output position from the first information signal when a modified information stream is reproduced on the device. further comprising means for storing a new exit position. 19. The apparatus of claim 16, wherein the initial position of the signal block contained in the fourth fragment directly after the second fragment in the second information signal is a new input position to the second information signal when the modified information stream is reproduced on the device. means for storing a new entry position. 20. The apparatus of claim 17, wherein the initial position of a portion of the information in the second fragment that follows the portion stored in the junction block is a new input position to the second information signal when the modified information stream is reproduced on the device, includes means for storing a new entry position. 21. The apparatus of claim 4, wherein if the amount of information in the first fragment of the second information signal that includes the input position from the input position to the end of the block of information in that fragment is less than SFA / 2, a block adapted to generate a junction block of information from the information in the first fragment after the input position and at least a portion of the information stored in the second fragment of the first information signal including the output position, a portion extending from the output point in the direction of the start position of the signal block in the second fragment A request has been made for the size of the junction block of information. 22. The apparatus of claim 21, wherein the junction block of information comprises information in the first fragment after the start position and only a portion of the information from the second fragment so as to also achieve a size requirement of the information in the second fragment before the portion stored in the junction block. . ·· ·· · · · · · · · · · · · · · · · · · · · · The apparatus of claim 21 or 22, wherein the initial position of the signal block contained in the third fragment directly after the first fragment in the second information signal is a new input position to the second information signal when a modified information stream is reproduced on the device, further comprising means for storing a new entry position. 24. The apparatus of claim 21, wherein the end position of the signal block contained in the fourth fragment directly before the second fragment in the first information signal is a new output position from the first information signal when a modified information stream is reproduced on the device. means for storing a new exit position. 25. The apparatus of claim 22, wherein the end position of a portion of the information in the second fragment preceding the portion stored in the junction block is a new output position from the first information signal when the modified information stream is reproduced on the device, it comprises means for storing a new output position. 26. The apparatus of claim 4, wherein the apparatus further comprises: - means for decoding a portion of the information in the first information signal before the exit point, for decoding a portion of the information in the second information signal after the entry point, means for generating the composite signal derived from the decoded portions of the first and second information signals, means for coding the composite signal, - means for coding the composite signal, * · · · · · · · · · · · · · · · · · · · · · · · means for adapting the encoded composite signal to one or more splice blocks of information fragments, wherein the size of the splice block of the information comprising the encoded composite signal may be variable and meets the requirement of: The SFA / 2 < block size of the information in the encoded composite signal < SFA and the means for writing the linking blocks of the information comprise the encoded composite signal into corresponding fragments. 27. A method of recording a real time information signal, such as a digital video signal, on a disc type recording medium, characterized by: wherein the data recording portion is further subdivided into fixed-length fragments, the method comprising: - reception of information signal, - processing the information signal into a channel signal for recording the channel signal onto a disc type record carrier, the processing comprising converting the information signal into blocks of channel signal information, - writing the channel signal to the record carrier, wherein the recording comprises writing the channel signal information into fragments on the record carrier, and wherein the processing further comprises converting the information signal to the blocks of information of the channel signal so that the size of the blocks of information may be variable and meet the following condition: SFA / 2 velikost channel signal block size S SFA, where SFA is a fixed fragment size. • α 99 9 · * * 1 1 1 1 1 1 1 1 1... 999 * 9 9 28. The method of claim 27, wherein the information signal is converted to channel signal information blocks such that successive sequence information blocks alternately meet the following relationships: SFA / 2 b channel signal block size b SFA, channel signal block size = SFA. 29. The method of claim 27, which converts the information signal into blocks of channel signal information such that successive sequence information blocks satisfy the following relationship: 2.SFA / 3 b block size of channel signal b SFA. A method of modifying a real-time information signal such as a digital video signal recorded in an earlier recording step on a disc type recording medium, characterized in that the data recording portion is subdivided into fixed-length fragments, wherein the information signal is converted into a channel signal prior to recording and then recorded on the record carrier such that blocks of channel signal information are recorded in corresponding fragments on the record carrier, the method comprising: receiving an output position in a first information signal recorded on the record carrier and for receiving an input position in a second information signal which may be the first information signal recorded on the record carrier, -Save information on input and output »C ···· · · · · ·« • ···· * * · φ 9 ς · 0 · t w · • »· 9 9 9 9 99 999 99 99 position, - generating at least one information junction block, wherein the information junction block comprises information from at least one of the first and second information signals, said information being upstream of the output position in the first information signal and / or downstream of the input position in the second information signal, and connecting block of information can be variable and fulfills the condition: SFA / 2 t the size of the junction block of information t SFA, where SFA is equal to the fixed length of the fragments, - writing at least one linking block of information into the corresponding fragment; -producing a modified stream of information from the record carrier. 31. The method of claim 30, generating a successive sequence of at most three linking blocks of information alternately meeting the following relationships: SFA / 2 channel block block size h SFA, a channel block block size = SFA. 32. The method of claim 30, generating a successive sequence of a maximum of two linking blocks of information alternately meeting the following relationship: 2.SFA / 3 t channel signal block size t SFA. · · * * * * * * * * * * * * * * * * * * * * * * * * * * * * ·· ·· · * · · · · · · · · · · · · · · · 33. A disc type record carrier having real-time information recorded thereon, wherein the record carrier has a data recording portion that is further divided into fixed-length fragments, the information signal being recorded on a record carrier encoded in channel form. , the information signal is divided into blocks of channel signal information, the blocks of channel signal information are written to fragments, the size of the blocks of information stored in the corresponding fragments is variable, and meets the following requirement: SFA / 2 block size of channel signal information SFA, where SFA is equal to a fixed fragment size. The disc type record carrier of claim 33, wherein the size of the successive sequence of blocks of information alternately satisfies the following relationships: SFA / 2 channel signal block size <SFA, a channel block block size = SFA. The disc type record carrier of claim 33, wherein the size of the successive sequence of blocks of information satisfies the following relationship: 2.SFA / 3 block size of the SFA channel signal. • · · «· ···· · · · ··· · ·· r 36. A device for reading a real time information signal, such as a digital video signal, from a disc type recording medium, characterized in that the information signal is recorded in encoded channel form in the data recording portion of the recording medium, wherein the data recording portion is further subdivided into fixed-length fragments, wherein blocks of signal information into the channel of encoded information are recorded into corresponding fragments, wherein the size of the blocks of information may be variable and satisfies the following relationship: SFA / 2A channel block information block size < SFA, where SFA is equal to fixed fragment size, the device includes: means for reading the channel signal from the record carrier, means for processing the signal for processing blocks of variable-length information and reading from the fragments into portions of the information signal, means for outputting the information signal.