Patent Application
20090046203
This patent application claims priority from German patent application 10 2007 038 861.8 filed Aug. 16, 2007, which is hereby incorporated by reference.
The invention relates to video data processing, and in particular to generating a video data stream, where interrupt and/or status data are transmitted between two apparatuses in addition to video data.
As is illustrated in exemplary representative fashion in
A known alternative to the use of separate input/output lines and interrupt lines for transmission between two such video data processing apparatuses is the retrieval of such items of information via a serial control bus such as for example according to I2C, SPI or Microwire buses. While the first-named approach has the disadvantage of limited resources and necessitates complicated circuit-board layouts, disadvantages of the second approach include limited bandwidth on the control bus. In many cases such buses are connected behind other buses, such as for example in the case of USB, PCI or Firewire, which further magnifies the problem.
There is a need for a technique for processing video data that makes possible a simple design approach with simultaneously efficient transmission of video data and additional data such as the interrupt data or items of status information.
According to an aspect of the invention, a video data processing apparatus includes a processing unit for processing input video data to provide processed digital video data, and a control interface within the processing unit for reading requests from a video receiver. The processing unit and/or a data insertion unit are place or incorporate interrupt and/or status data into the video data, and the output generates the processed digital video data having the interrupt and/or status data placed or incorporated thereinto in correspondence with a read request that has occurred.
The processing unit and/or the data insertion unit preferably place or incorporate the interrupt and/or status data as self-contained data between the digital video data proper.
The processing unit and/or the data insertion unit may place or incorporate the interrupt and/or status data as self-contained data into data stream regions not used for the digital video data proper. The processing unit and/or the data insertion unit may place or incorporate the interrupt and/or status data into a video blanking region. The video blanking region can be in particular a blanking region or a blanking interval.
The processing unit and/or the data insertion unit may place or incorporate the interrupt and/or status data in a marked region of the output data stream. The processing unit and/or the data insertion unit may place or announce the interrupt and/or status data per se and/or their position in a header segment of the output data stream. The processing unit and/or the data insertion unit may place or incorporate the interrupt and/or status data in a fixedly specified region of the output data stream.
The interrupt and/or status data are preferably placed or incorporated as self-contained data between the digital video data proper. The interrupt and/or status data are preferably placed or incorporated as self-contained data into data stream regions unutilized for the digital video data proper. The interrupt and/or status data can be placed or incorporated into a video blanking region. The interrupt and/or status data are preferably placed or incorporated in a marked region of the output data stream. The interrupt and/or status data can also be placed or announced in a header segment of the output data stream. Alternatively, the interrupt and/or status data can also be placed or incorporated in a fixedly specified region of the output data stream.
Furthermore, what is independently preferred as further component of a video data processing system is a video data processing apparatus for receiving an output data stream of such an apparatus or of such a method, having an input for the input of video data having the interrupt and/or status data placed or incorporated thereinto, having a processing unit for separating the video data from the interrupt and/or status data placed or incorporated thereinto and having an output for the output of the processed video data or of the processing unit or of a further processing unit for the further processing of the video data.
Audio data may be associated with the video data or the video data may comprise audio data in addition to image data. The data in question can be fixedly associated data blocks but also signals or data sequences to be processed separately from one another.
Because the digital video bus used in every case is used as an output line for transmitting the output data stream having the video data or also, as applicable, audio data linked therewith for additionally further informational data such as status and interrupt messages, one or a plurality of separate lines for transmitting such status and interrupt data are omitted. Alternatively, such data can be employed as additional video data lines in order for example to enhance the total throughput of video data. It is especially preferred that additional data in the form of status and interrupt data are inserted into regions of the data stream in which no active video data or audio data are being transmitted, that is, in particular, in so-called video blanking regions. Also advantageous are embodiments in which a header segment, a so-called header, indicates and/or signals the presence of such items of information. In addition or alternatively, provision may also be made for inserting such items of information at defined positions within the data stream.
A receiver-side video data processing apparatus is desirably generated in corresponding fashion as a receiver for receiving such an output data stream, which apparatus can separate, out of the received output data stream, the received video data and, as applicable, audio data from interrupt and/or status data placed or incorporated thereinto.
Possible fields of application are in particular the placement of a macrovision status, a video decoder status, an audio decoder status, RDS data, an interrupt request and/or generic messages into the data stream of video data and/or audio data.
These and other objects, features and advantages of the present invention will become more apparent in light of the following detailed description of preferred embodiments thereof, as illustrated in the accompanying drawings.
The video data processing apparatus 100 includes an input 102 for the input of video data, in particular digital video data vi; an integrated processing unit proper 102 for processing at least the input video data vi; an output 104 for the output of the processed video data onto the data line 16; and a control interface 106 for read requests of the video receiver 14. The processing unit 100 and/or a data insertion unit place or incorporate interrupt data di and/or status data ds (hereinafter identified by reference character s) into the input video data vi. As processed video data or as digital output data stream vo, the output interface 104 generates the input video data vi having interrupt and/or status data s placed or incorporated thereinto. Here the requisite interrupt and/or status data are placed in compliance with the applicable video standards.
The output interface 104 may be implemented as a digital unidirectional output that transports video signals, in particular, output data stream vo. Output data stream vo proper, for example, video data stream in compliance with ITU-R BT.656-4 (February 1998), comprises useful data, such as for example, useful video data, and blanking, that is, times in which no useful data occur. Other data such as for example Teletext or audio data complying with, for example, Rec. ITU-R BT.1364-1 (August 2005) may be transmitted in the corresponding blanking intervals.
The receiver 14 controls the video data processing apparatus 100 via the control line 15 in the form of the control bus.
The control bus 15 is commonly relatively very slow and, in the case of read operations, for example “1. Read request,” greatly retards present-day processors having processing speeds greater than the transmission speeds of the control bus. While bus speeds are currently in the 100 kHz range, the processing speeds of current processors are in the megahertz and gigahertz range, so that replies via the same slow control bus 15 come back too slowly.
The problem is remedied through the use of an asynchronous model, and the control bus 15 may be used between the video data processing apparatus 100 and the receiver 14. The processors of the video data processing apparatus 100 and the receiver 14 may operate at processing speeds greater than the transmission speeds of the control bus 15. In particular, there is no problem if the ratio of processing speeds to transmission speeds is equal to a thousand or more.
Given an appropriately implemented asynchronous model, the read—i.e., “1. Read request” in FIG. 1—is performed as a write. In particular when so-called posted writes are employed as write procedures, this can be effected without major retarding impacts for the processor or processors.
A reply—i.e., a “2. Asynchronous reply to 1.” Illustrated in FIG. 1—is then sent via the link of the video data stream, that is, of output data stream vo. It is feasible that a reply is sent via the output data stream vo for every read request received via the control interface 106.
Optionally, by a repetitive sending procedure, the reply can be sent to the receiver 14 again and again via the output data stream vo until a signal or data signalizing and bringing about a termination of repetitive sending are received via the control line 15 and the control interface 106. This saves repetitive sending or read requesting via the slow control line 15.
Additional links to the receiver 14, for example interrupt lines known per se, can also advantageously be omitted if appropriate instructions are placed into the output data stream vo as “3. Independent messages” in
As can be seen from
Furthermore, the video data processing apparatus 100 displays the control interface for the read request of the video receiver 14. In the embodiment illustrated, the control interface 106 communicates with a control unit 108 via a bidirectional link 110.
The control unit 108 is also linked via (in particular bidirectional) lines or buses to further processing unit or units 110. The control unit 108 controls corresponding processing units 110 in such fashion that these analyze and/or process the received video data vi and, as applicable, audio data. To this end, along with the read request, the control unit 108 can also send and/or receive interrupt and/or status data di, ds to a data insertion unit 113, also informational and/or control data c.
According to the first exemplary embodiment, digital video data vi are preprocessed and, as applicable, also examined for data structures in a first processing unit 110 receiving digital video data vi from the input. Optionally, a search can also be made in received video data vi for data stream regions in which there are redundant video data or no video data, in order that interrupt and/or status data di, ds can be placed into such regions of the data stream instead of the original data.
As applicable, the preprocessed video data vix are output by the processing unit 110 to a data stream encoding unit 112, which is likewise operated under the control of the control unit C. Data stream encoding unit 112 generates the input-side video data vix, preprocessed as applicable, and, as applicable, audio data as a formatted data stream viy, this formatted data stream viy being applied to the input side of the data insertion unit 113. Under the control of the control unit 108, the data insertion unit 113 inserts interrupt data di and/or status data ds into appropriate data stream regions. Optionally, further data, for example audio data oi or other informational data, can also be applied to a further input of the data insertion unit 113 directly from the first processing unit 110, via an optional further data path, and employed for control or insertion.
The data insertion unit 113 modifies received formatted data stream viy in such fashion that output data stream vo output at the output is generated with video data, audio data as applicable, and additionally the inserted interrupt and/or status data di, ds.
Optionally, a further combination can occur in such fashion that a single processing component modifies receiver-side video data vi and/or audio data oi directly to output data stream vo into which this one processing unit is itself already placing the corresponding additional data, in particular interrupt and/or status data di, ds.
Finally, further modifications of the several video data processing apparatuses TX, TX°, RX are possible, in particular modifications through integration of various functions in a single design element or a further splitting into still more components.
In terms of method, interrupt and/or status data are thus embedded as additional data in a sequence of digital video data and, as applicable, audio data and jointly generated in a single output data stream for a further video data processing apparatus.
Although the present invention has been illustrated and described with respect to several preferred embodiments thereof, various changes, omissions and additions to the form and detail thereof, may be made therein, without departing from the spirit and scope of the invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2007 038 861.8 | Aug 2007 | DE | national |
