TWI269578B - Data stream filtering module and method - Google Patents

Abstract

A data stream filtering module including a first data filtering module, an output record module, and a status store module is described. The data stream is transmitted by packets. A section to be filtered may be allocated in more than one packet. The output record module records the output status of each piece of data. The status record module stores the filtering result of each piece of data. The first data filtering module attaches a piece of marking bits to each piece of data to identify whether the piece of data has passed the filtering and thus to save the storing space.

Description

1269578 IX. The invention relates to a data stream filtering device and a method thereof, and more particularly to a data stream filtering device in a demultiplexing module of a digital television signal processing device and method. [Prior Art] A digital video broadcasting system transmits data by a transport stream, which is a single data stream synthesized by a plurality of programs. The digital television receiving device demultiplexes and decodes the transport stream synthesized by the plurality of programs, and finally outputs the audio and video contents of the selected one of the programs. The transport stream is transmitted in the form of a packet, which is called a transport stream packet. The transport stream packet is composed of a header (Byte) of 4 bits (Byte) and a payload (Payload) of 184 bytes, wherein the header carries information such as Packet Identity and the payload carries Content such as Packetized Elementary Stream or Program Specific Information. The element stream packet is also composed of a header and a payload, and the payload carries the specific content of the program such as video, audio and subtitles. The complete program special information is a table, which is divided into multiple parts for transmission. Each component consists of 14 bytes and payloads of the header, and is carried in the payload. Detailed information about the program, such as program schedules, online information, etc. The multiplexed module (DEMUX) finds the element stream packet, program special information, etc. required for the currently selected program from the transport stream, and allocates it to the corresponding buffer, which needs to filter various types of data. Please refer to ISO/IEC 13818-1 for the number 269578 TV broadcast transmission standard. In May, reference to Figure 1 is the functional component of the multiplexed module (DEMUX) 10 and the data processing flow. As shown in Figure 1, the multiplexed module includes a synchronous mode ▲ (SYNC) 11, a packet identity filter module (PF) 12, an adaptation field analysis module (AF) 13, and a descrambling module (DES) 14 , data filtering module (df) 15 and distribution module (DIS) 16. The transport stream first enters the synchronization module u, and the synchronization module 11 checks whether it is a transport stream packet of 188 bytes, and then sends it to the packet identity filter module 12, otherwise discards it, and blocks the identity filter module, And 12 selects a packet required for the selected program according to the system's packet identifier table (piD table) and sends it to the adaptation field parsing module 13; the parser # and parsing module 13 parses the pCR information of the transport stream packet. And sending it to the descrambling group 14; the descrambling module 14 descrambles the data; the data filtering module 15 transitions the prime stream packet and the program special information; and allocates the mode, and 16 filters the data. Assigned to a different buffer (fifo) 丨7. The filtering of the data stream is now described by the data filtering module 15 in the prior art. Because the element stream packet structure is simple, and the header to be filtered does not cross the transport stream packet (as specified by the DVB standard), the filtering of the element stream packet is relatively simple. For example, the element stream packet header 4 bytes are filtered to determine whether it is a desired element stream packet. For program special information, the system needs to filter each component header...the retention tuple to be more of the required components. Since the dvb standard does not specify the position of the 14 bytes of the program specific information component header in the transport stream packet, the header of the component is likely to be distributed in the two transport stream packets' and the two Transport stream packets of other nature between transport stream packets. ^夕1269578 For Langmu's special information, the filter of 士, yg,, _, β, 邛, 邛, 邛, 邛, 邛, 邛, 邛, 邛, 邛, 邛, 邛, 邛 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 However, since one component: two == is placed in two non-contiguous transport stream packets, this is two: == with the partial header. The existing processing method will be: a bit of two \ ° 卩 硕 硕 暂 暂 暂 暂 暂 暂 , , , , 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 - The selected program of the road needs to process more than 16 items = transport stream packets dedicated to 32 packets of identity (additionality), and the packet identity is mostly occupied by the transport stream packet carrying the special information of the program, considering the boundary condition, It is necessary to add a capacity of MW bytes to store the uncompleted component headers, but this increases the wafer area. SUMMARY OF THE INVENTION Therefore, the object of the present invention is to provide a data stream filtering module that utilizes a small storage space to process program specific information of a delivery stream price of % TS). Another object of the present invention is to provide a data stream filtering module that can process program specific information of a transport stream more efficiently. It is yet another object of the present invention to provide a data stream filtering module that reduces the area of the wafer. According to the above object of the present invention, a data stream filtering module is provided for considering a component of a program special information of a transport stream (TS), wherein the data stream filtering module includes a state storage module. Receiving and storing the section filtering status information; a packet identity table's output status of the 5 sections; and a program special fund 1269578 矾 filter module 'receiving component' (secti〇n) 2 header and generate the filtering status information 'The filtering status information records whether the header passes the filtering, and adds an iconic field at the end of the component, the flag field indicates whether the section passes the transition. The present invention has at least the following advantages, each of which may have one or more advantages. The data stream filtering module of the present invention can process program specific information of the transport stream (tranSp〇rt stream, Τ§) by using a small storage space. The data stream filtering module of the present invention can process program specific information of the transport stream more efficiently. The data stream filtering module of the present invention can reduce the area of the wafer. [Embodiment] Referring to FIG. 2, the data stream filtering module (DF) 150 of the present invention includes a program special information filtering module (PSI) 151, an element stream packet filtering mode φ group (PES) 152, and a state storage module. (Config Table) I53 and buffer (FIFO) 154. As described above, before the transport stream packet enters the data stream filter module 150, the packet identity filter module 12 filters the packet identity according to the packet identifier table (PID TABLE) 130, and selects the transport stream packet required for the program. Can enter the data filtering module 15〇. The program special information filtering module 151 filters the components of the program special information; the element stream packet filtering module 152 filters the element stream packets. The element stream packet filtering module 152 performs a transition to the element stream packet header to determine whether it is the required element stream packet. If yes, the 7G stream packet is output through the buffer 154 8 8 1269578, otherwise the element stream packet is discarded. As mentioned earlier, the header of the ISO/IEC 13818·1 element stream packet can only exist in one transport stream packet. Therefore, the filtering of the element stream packet is relatively simple.

The state storage module 153 is configured to store the filtering state of each component of the program special information, which is a table of Νχ(η+2) bits, and the parent entries are η+2 bits. Where Ν is the number of packet identities that need to be processed; among the η+2 bits of each entry, the η bit is a packet identity index (PID-Index) filled in by the software, indicating that the filtered special information carrying the program is The location of the packet identifier of the transport stream packet in the packet identity table 13〇; one of the other two bits is an enabling bit of the entry (Enabie), and the software can open the entry by setting “Γ” (valid) ), set "〇" to close the entry (invalid), so that software control filtering can be implemented; another bit is the error bit (Eiror) of the entry, indicating whether the header of the received component has passed the filtering. If it does not pass, set "Γ" and pass it to keep "〇". When a total of 14 headers of a component header is received, if the error bit is "〇" and the enable bit is "Γ", the component is considered to be filtered. The program special information filtering module 151 is for the program. The special information is divided into 14 bytes of each component header to determine whether it is the required component. For each component filtering, as long as one of the 14 bytes of its header is not By filtering, the component should be discarded. Only when the 14 headers of the component header are all filtered, the component can be used by the system. Therefore, in the filtering process, the state storage module 153 is wrong. The bit can only be overwritten with “Γ” and cannot be “〇”, “覆盖”, and the corresponding entry is reset before the first byte of each component header is filtered to ensure the previous component. The filtering result does not affect the current component. The header of the component of a program special information may be distributed in two transport stream packets, and the two transport stream packets are transmitted by multiple others. The flow packet interval, in some cases, completes a component header: needs = to receive the 14 bytes of the component header. The present invention uses the state storage module 153 to record the component headers. Filtering information, so there is no need to store the entire header 14 bytes, as described later. For example, when ν=32, hit: bit (2 is equal to 32, corresponding to 32 entries in the packet identification table), The state storage module of the present invention only needs 32 χ (5+2) bits of storage space, and the same state of the art data flow through the 泸 module requires Mm (bytes) χ 8 (8 bits per octet) (meta) storage space of the bit ^ Ming to achieve program special information only requires one-sixteenth of the capacity of the existing storage device 'This can save a lot of wafer area. _ In the special information stream packet filtering, the following may appear The headers of several (1)-program special f-signal components are distributed in one pass two== two and the header is filtered. The program special information filter mode corresponds to (4)/heart state storage module 153, state storage module 153 Composition:; points =:==:: holding τ. The program _ news The program is specially output. When the component is completely converted, the filter module will add a symbolic word at the end of the filter module, indicating whether the component is reincarnation, or not. The load of a transport stream packet is recorded in the packet identity table. If the component body: part of the table is distributed in other transport stream packets, the system will be packetized by other transport streams according to the rounded record output of the packet. Carrying the component 1269578, finally, the system adds an iconic field to the tail of the component according to the error bit corresponding to the state storage module 153. The header of a program special information component is distributed in a transport stream packet, 1 ▲ w Ren does not pass the filtering. The program special information filtering module 151 2 Κ ^ to the pain, the storage module 153, the state storage module 153 to the corresponding identity of the item of the wrong position "1", the program special information flow two = The part t is discarded * and the discarded information is stored in the packet ^. If the payload of the component is distributed in other transport stream packets, it is discarded according to the output record of the packet identity table and the error bit corresponding to the state storage module 153. The headers of the C 3 1 , OFF, ☆, and program special information components are distributed in two packets, and the header bits of the previous transport stream packet are filtered. The /By special stream packet filtering module 15 sends the filtering result to the state ^ module 153 'the state storage module 153 corresponding to the error bit holding. The part header is output through the buffer 154, and the output information is automatically recorded in the packet identification table. Since the binary portion distributed in the component of the previous transport stream packet has been output, regardless of whether the remaining header headers distributed in the subsequent transport stream packet pass the filtering, the data stream transition module P will be based on the packet identity. The output records of the table are distributed over subsequent transport stream packets = other parts of the component (including headers and payloads). If the remaining header bytes are also filtered, the program special information is passed: the module 15i sends the information to the state storage module 153, and the error bit corresponding to the state storage module remains "〇" ". Finally, the special information over the ‘two groups 151 added at the end of the component indicates that it passed the filter sign 14 word slave. If the remaining headers 8 1269578 bytes of the component of the latter transport stream packet are not filtered, the error bit corresponding to the state storage module 153 will be set to "1", and the program special information filtering module 151 will be The component tail adds an iconic field that is not filtered, and the software discards it when it is processed. (4) The header of a program specific information component is distributed in two transport stream packets, and the header bytes distributed in the previous transport stream packet are not filtered. The program special information filtering module 151 sends the information to the state storage module 153. The state storage module 153 sets the corresponding error location ''1', the current part of the component is directly discarded, and the discarded information is recorded in the packet identity. In the table, the system discards the subsequent content of the component according to the error bit of the state storage module and the output record provided by the packet identity table. The following example illustrates the operation of the data stream filtering module of the present invention. The transmission stream packets of the program special information: TS1, TS2, TS3 and TS4 are sequentially sent to the data stream filtering module for filtering, wherein TS1 and TS3 have the same packet identity, and TS2 and TS4 have another body injury TS1. And TS3 carries a program special information component a. The different mouth p points ' are the first 1st byte and the first U_14 byte respectively; TS2 and TS4 carry the other 1st to 8th byte Different parts from the header of the ninth component B, 9-14 bytes respectively, as shown in the following table: TS1 (PID-Index=l) TS2 (PID-Index=2)

Component A header 1 -10 digits

1-8 group of component B header

(D 12 1269578 TS3 (PID_Index=l ) TS header and matching field Component 11 header 11 - 14 bytes TS header and matching field Component 9 header 9-14 bytes

When TS4 (PID_Index=2) is filtered, it is assumed that the byte of the component header carried by TS1 and TS4 is filtered, and the byte of the component header carried by TS2 and TS3 is not filtered. Before filtering, the status of the corresponding entry of the state storage module 153 is as follows: Status storage module entry 〇

Enable Error PID Index Status Storage Module Entry 1 1 0 PID_Index= 1 1 0 PID—Index = 2 After TS1 filtering, the status of the Config Table entry is as follows:

Enable Error PID Index 1 0 PID—Index= 1 1 0 PID—Index = 2 Status Storage Module Table Item 〇 Status Storage Module Entry 1 After TS2 filtering, the status of the Config Table entry is as follows:

Enable Error PID Index Status Storage Module Table Item 〇 Status Storage Module Entry 1 1 0 PID—Index = 1 1 1 PID—Index= 2 After TS3 filtering, the status of the Config Table entry is as follows: 8 1269578

Enable Error PID—Index Status Storage Module Entry 0 1 1 PID Index = 1 Status Storage Module Entry 1 1 1 PID Index=2 After TS4 filtering, the status of the corresponding items in the c〇nfig Table is as follows: Enable Error PID Index Status Storage module table entry 1 1 1 PID - Index = 1 Status storage module entry 1 1 1 PID - Index = 2

_ ^Because the system does not set the special storage part of the program special information part header, the component header group carried by the TS1 is filtered, and since the TS1 carries the first transmission stream of the component A The packet will be output. The component header carried by θ 82 does not pass the filtering, and since the TS2 carries the first transport stream packet of the component ,, it will be directly discarded*. Although the header byte of the component carried by TS3 has not passed the filtering, since TS1 has been sent, Ts3 will also be sent out and the system will add a standard field at the end of component A to indicate the component A. Did not pass the filter. TS4_ passes through, but since the top has not passed and is discarded, TS4 will also be discarded directly. [Can be * this & clearly according to the rounding record of the packet identity table and the error bit of the storage module 153 judged that the #前Program special information group = sub-output or discard, after filtering and adding at the end of the indication Whether or not the time period, in the subsequent processing, the software determines whether to process the part of the data according to the target. The information component header bit group is over. The data stream filtering module 150 of the present invention is a flow chart of the program special consideration method of the present invention. Step 3 Μ, 1269578 2 The program special information filtering module 151 filters the current part of the component (secti〇n), step 3〇2, and the program special information filtering module 151 stores the filtering result to the state. The storage module 153, step 3〇3, determines whether the component (secti〇n) has an output record according to the record of the packet identity table 130, and then jumps to step 305 to output the current part of the component (secti〇n). Knife, if no, jump to step 304, judge whether the component section passes the filtering according to the record of the state storage module 153, if yes, skip to the step, output and output the current part of the component part (secti〇n), otherwise jump To step 306, the current portion of the component (secti〇n) is discarded, and step 307' stores the output record. The present invention has at least the following advantages, each of which may have one or more advantages. The data stream filtering module of the present invention can process program specific information of a transport stream (transp0rt stream, TS) by using a small storage space. The data stream filtering module of the present invention can process program specific information of the transport stream more efficiently. The data stream filtering module of the present invention can reduce the area of the wafer. Although the present invention has been described above in terms of a preferred embodiment, it is not intended to limit the invention, and it is obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. The scope of the invention is defined by the scope of the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS In order to make the above and other objects, features, advantages and embodiments of the present invention more obvious and obvious, the detailed description of the drawings is as follows: 8 15 1269578 Figure 1 shows the existing solution multi-mode The structural diagram of the functional modules of the group; the second diagram shows the structural diagram of the functional modules of the data stream filtering module of the present invention; and the third diagram shows the special information of the filtering program of the program special information filtering module of the present invention. Flow chart for partial header bytes. [Main component symbol description] 10: Demultiplexing module 12 · · Packet identity filtering module 14 : Desmuting module 16 : Distribution module 120 : Packet identity filtering module 150 : Data stream filtering module 152 · · Element Stream packet filtering module 154: buffer 11: synchronization module 13: adaptation field parsing module 15: data stream module 17: buffer 130: packet identity table 151: program special information filtering module 153: state storage module Group 16

Claims (1)

1269578 X. Patent application scope: 1. A data stream filtering module for filtering a component of a program special information of a transport stream (TS), the data stream filtering module comprising: a state storage module Receiving and storing a section filtering status information; a packet identity table recording the output status of the section; and a program special information filtering module receiving the header of the section and generating the filtering Status information, the filtering status information records whether the header passes the filtering, and adds an iconic field at the end of the component, the flag field indicating whether the section is filtered. 2. The data flow filtering module of claim 1, wherein the state storage module is a table. 3. The data flow filtering module described in claim 2, wherein the table is for recording N*(n+2) bits, where N is the number of packets (PID) to be processed. η is a packet identity index (PID_index) for filling, the two bits are a consistent energy bit (enable) and an error bit (error), and the enabling bit (enable) records the table (table) Whether it is valid, the error bit records whether a part of the header has been received or not. 1269578 4. A data stream filtering method for filtering a component of a program specific information of a transport stream (TS), the data stream filtering method comprising: filtering a current part of a component (secti〇n) And storing the filtered result; determining whether to output the current part of the component (secti〇n) according to the output condition of the component (secti〇n) and the filtering result: If the component has an output record, the current portion is output; the record is filtered, and if the component is not output, the current portion is output; if the 5H component (section) If there is no loss, then the current part is discarded; the record is recorded, and the result of the filtering is a non-sense record; and the flag is The signature field is added to the tail of the sex & t edge component (SeCtί〇η). The segment indicates whether the segmentation part passes the transition. 8 18