GB2534232A

GB2534232A - Multimedia capture device

Info

Publication number: GB2534232A
Application number: GB1500878.2A
Authority: GB
Inventors: Roe Adrian; Robinson Dom; Strong Steve
Original assignee: ID3AS-COMPANY Ltd
Current assignee: ID3AS-COMPANY Ltd
Priority date: 2015-01-19
Filing date: 2015-01-19
Publication date: 2016-07-20
Also published as: GB201500878D0

Abstract

A capture card 3 for connection to an expansion slot of host computer 7 communicates data as a network card on a data bus of the host computer. It comprises: external device interface 31 to receive content data from audio-visual (AV) device 27, e.g. cameras; server module 25 providing received content data to the host computer as a network resource; and network card driver module 15 to format the received content into network formatted content data based on a predefined network layer protocol and to transmit the network formatted content data to the host computer via a host computer interface 9a. By presenting the AV capture card to the host computer as a generic network interface where captured AV data is transmitted as a stream of network data packets, the need of specific custom device drivers is eliminated, thus improving compatibility. Examples of data bus connectors are USB, PCI or PCMCIA.

Description

Intellectual Property Office Application No. GII1500878.2 RTM Date:21 Jule 2015 The following terms are registered trade marks and should be read as such wherever they occur in this document: Datapath, Firewire, Hauppauge!, HDM I, Linux, Pinnacle, RCA, Unix Intellectual Property Office is an operating name of the Patent Office www.gov.uk /ipo Multimedia Capture Device

Field of the Invention

[0001] This invention relates to the field of multimedia technology, particularly to a computer interface card for multimedia data capture.

Background

[0002] The multimedia production and broadcast services sectors are increasingly using computers to process audio and video (AV) signals. Computer interface cards for multimedia data capture are generally known, providing an audio/visual (AV) signal conversion device that is physically connected to a host computer system using a bus interface. Such mechanical computer interface cards enable an AV signal from an external source AV device, such as a video camera or other form of AV production system, also physically connected to the interface card, to he converted and provided to the host computer computational software environment directly. Typically, this AV capture task has been provided by a dedicated device remote from the host computer, or by a peripheral or expansion card, such as a sound and/or video capture card, attached to an expansion slot of a host computer using a expansion bus interface such as PCI (Peripheral Component Interconnect), PCMCIA (Personal Computer Memory Card International Association), or the like. Capture devices can also take the form of an integrated circuit fitted on the motherboard itself. These known capture devices implement signal processing modules or circuitry to process AV signals received from connected external devices over a standard AV or data connection.

[0003] Many software applications that require input from AV sources are developed for single operating systems, and often for specific distributions of those operating systems. This is largely down to the relatively limited demand for these AV capture card devices, leading the operating system vendors to push the responsibility of software device drivers back to the capture card vendors. With ever proliferating operating system distributions, the task of supporting each distribution with each type of AV capture card has become untenable.

[0004] Vendors such as BlackMagic, Osprey, Hauppauge, Pinnacle and Datapath typically only certify a very limited number of motherboards, and on those motherboards they in turn support only a minimal number of operating systems. Changing a single component, such as the CPU or even a seemingly unrelated network card interface or display interface, can cause instability or incompatibility with the AV device. Rewriting the driver then requires deep technical knowledge of the AV capture device and deep knowledge of the operating system (OS) and motherboard architecture. This means that applications developers requiring a particular combination of AV capture device and host system platform are often very limited to the platforms that their applications can run on, and in a market where the platforms' form factor can make a significant difference to the end users' operational requirements, this is impacting development and growth in the sector.

[0005] What is desired is a system that provides improved compatibility of capture card functionality with modern operating systems.

Summary of the Invention

[0006] Aspects of the present invention are set out in the accompanying claims.

[0007] According to one aspect of the present invention, a device is provided for connection to an expansion slot of a host computer, the device comprising a host computer interface configured to communicate data as a network card on a data bus of the host computer, an external device interface configured to receive content data from a connected audio/visual device, a server module configured to provide received content data to the host computer as a network resource, and a network card driver module configured to format the received content data into network-formatted content data based on a predefined network protocol and to transmit the network-formatted content data to the host computer via the host computer interface.

[0008] The host computer interface may comprise a standard data bus connector and is configured to communicate data as a network card on a standard data bus of the host computer. The standard data bus may be a USB bus, or a PCI-or PCMCIA-based bus.

[0009] The external device interface may comprise one or more connectors having a respective connector type. The external device interface may be configured to receive content data from the audio/visual device using a standard data communication protocol. The audio/visual device may he a camera.

10010] The server module may be configured to respond to a request for data from an application executed on the host computer via an application layer protocol.

[0011] A signal processing module may be provided to perform one or more of analogue to digital conversion, filtering, decoding, encoding, re-encoding, compression, encryption, colour balancing, scaling and watermarking of the received content data. [0012] The formatting module may be configured to format the content data into Internet Protocol data packets.

[0013] Preferably, the AV-network card is configured as a generic network card supported by a driver on the host computer, identified by a network card identifier stored in a read-only memory.

[0014] In another aspect. the present invention provides an apparatus for capturing multimedia signals from a connected device and transmitting the captured signals to a computer system as network-formatted data through a network card driver.

[0015] In yet another aspect, the present invention provides a method for capturing and providing content data by a peripheral device connected to a host computer as a network adapter, the method comprising the peripheral device receiving content data from a connected audio/visual device, formatting the received content data into network-formatted content data based on a predefined network protocol, and transmitting the network-formatted content data to the host computer via a host computer interface. [0016] In further aspects, there is provided a computer program storing computer-readable instructions for causing a programmable device to become configured as one of the above devices.

Brief Description of the Drawings

[0017] There now follows, by way of example only, a detailed description of embodiments of the present invention, with references to the figures identified below. [0018] Figure 1 is a block diagram showing the main components of a multimedia data capture system including an AV-network card according to an embodiment of the invention.

[0019] Figure 2 schematically illustrates an exemplary modular add-in card including a local expansion bus connector and an embedded signal processing module according to an embodiment.

[0020] Figure 3 is a flow diagram illustrating the main processing steps performed by the system of Figure 1 according to an embodiment.

Description of Embodiments

[0021] Figure 1 is a block diagram schematically illustrating a multimedia data capture system 1 according to an embodiment. The system 1 includes an AV-network card 3 that is connected to a host computer 7 as a network adapter, to communicate captured multimedia content to a data bus 5 of the host computer 7 as network-formatted data via respective bus interfaces 9a,9b. The data bus 5 is an industry standard data bus for connecting devices, such as expansion (also referred to as peripheral) cards and adapters, to the motherboard of the host computer. Examples of well-known standard data buses include Industry Standard Architecture (ISA), PCI or PCMCIA, or any known variants such as PCI-X, PCI Express, CardBus, CardBay, or the like. It is appreciated that the host computer 7 may comprise a plurality of data buses [0022] In the present embodiment, the AV-network card 3 has a form factor of an expansion card for connection to a typical expansion slot of a host computer 7, such as a PCI-or PCMCIA-based expansion card. Preferably, the AV-network card 3 is configured as a generic network card or adapter that is compatible with any one of a plurality of network drivers 10 natively supported by all modern operating systems, for example NE1000/2000-compatible generic Ethernet adapter drivers, which are natively supported by DOS, Unix, Linux, Microsoft Windows (RTM) and Mac OS (RTM) platforms. The AV-network card 3 is identified by a network card identifier 11 stored in a ROM (read-only memory) 13 and includes a network card driver module 15 that formats data into network-formatted data for transmission to the host computer 7 via the data bus interface 9, based on a standard network/transport layer protocol, such as IP. TCP/IP, UDP, or the like.

[0023] Host computer 7 may be a desktop computer, a laptop or a dedicated AV appliance, having a processor 17 to concurrently execute an operating system 19 and components/applications associated therewith stored for example in a memory 21. The applications include an AV application 23 to request and process data from an external data source. In this embodiment, the AV application 23 is configured to request and receive data from a data server module 25 hosted on the AV-network card 3, over a network connection established between the host computer 7 and the AV-network card 3 connected to the expansion bus 5. The data server module 25 is configured to respond to a request from the AV application 23 for data captured from an external AV source device 27. The data server module 25 may he configured to communicate with the host computer 7 and the AV application 23 via an application-layer transmission protocol such as HTTP (Hypertext Transfer Protocol), REST (Representational State Transfer), HLS (HTTP Live Streaming), FTP (File Transfer Protocol), RTP (Real-lime Transpot Protocol), RPC (Remote Procedure Call), or the like. Alternatively or additionally, the data server module 25 may be configured to encode and transmit structured and/or serialized data to the host computer 7, for example using XML, Protocol Buffers, or the like.

[0024] The AV-network card 3 also includes an AV data processing module 29 configured to capture AV content from an external AV source device 27, as a high speed serial or parallel data transfer via an external device interface 31. The external device interface 31 includes an industry standard connector for connection to one or more AV source devices. The connector may be a physical audio/video connector such as SDI (Serial Digital Interface), HDMI (High-Definition Multimedia Interface), RCA, SCART, S-Video, optical, or the like, or a physical device connector, such as USB (Universal Serial Bus), Firewire, SCSI (Small Computer System Interface), or the like. As those skilled in the art will appreciate, the external device interface 31 may include more than one connector, each having a respective connector type for connection to one or more AV source devices. The captured AV content may be live or pm-recorded video and/or audio content received from a video camera or other AV source, in raw or encoded data formats. The AV data processing module 29 may include circuitry and/or sub-modules to perform typical signal processing of the captured AV content data, including one or more of analogue to digital conversion, filtering, decoding, encoding, re-encoding, compression, encryption, colour balancing, scaling, watermarking, or the like, which are well-known per se, and need not he described further.

[0025] The network card driver module 15, data server module 25 and AV data processing module 29 may be provided as a single or combination of processing modules 33 of the AV-network card 3, for example as software or computer-executable instructions stored in a memory (not illustrated) and executed by a microprocessor (not illustrated), or as integrated circuitry such as ASIC (application-specific integrated circuit) or FPGA (field-programmable gate array) provided on a printed circuit board of the AV-network card 3, and electrically coupled to the mechanical expansion bus intcrfacc 9a and external device intcrfacc 31.

[0026] In this way, the present embodiment provides an expansion card with AV capture device functionality, which is presented to the host computer environment as a generic network interface card device and operable to transmit captured AV data to the host computer as a readily receivable stream of network data packets that encapsulate the captured AV data, thereby eliminating the need for specific custom device drivers as required by traditional AV capture devices in order to interface with particular associated operating systems. An exemplary add-in card 3 including a local expansion bus connector 9a, an external device interface 31, and one or more processing modules 33 is schematically illustrated in Figure 2.

[0027] A description has been given above of the components forming part of the multimedia data capture system 1 of this embodiment. A more detailed description of the operation of these components will now be given with reference to the now diagram of Figure 3, for an example computer-implemented multimedia data capture process embodiment using the AV-network card illustrated in Figures 1 and 2. In this exemplary embodiment, the data bus 5 on the host computer 7 is a standard PCI-based bus and the predefined network/transport layer protocol is the Internet Protocol (IP).

[0028] As shown in Figure 3, the process begins at step S3-1 where the operating system 19 executed by the host computer 7 queries the PCI bus 5 at startup time to identify and initiate all connected expansion devices. For example, in response to receiving, at step S3-3, a query from the host computer 7 via the expansion bus interface 9a, the AV-network card 3 retrieves and transmits the network card identifier 11 back to the host computer 7, at step 53-5. At step 53-7, the operating system 19 determines the system resources (e.g. memory space, 1/0 space, interrupt lines, etc.) that are needed for the AV-network card 3 based on the received network card identifier 11 and the associated network card driver 10 loaded from memory 21, allocates the determined resources accordingly, and informs the AV-network card 3 of the allocated resources on the host computer 7, via the expansion bus interface 9a. As those skilled in the art will appreciate, the process of identifying and initiating a PCI-based network card is well-known in the art and may vary depending, for example, on the network card identifier 11 and associated network adapter driver 10.

[0029] At step 53-9, the AV-network card 3 initiates the network card driver module 15 and the data server module 25, to configure the AV-network card 3 as an network-based service for providing content data. In this embodiment, the data server module 25 is a lightweight web server configured to process requests and to provide requested content data using standard network interface mechanisms, such as REST or HTTP. As those skilled in the art will appreciate, the data server module 25 will be configured as a network resource having a network address on an local network established by the operating system 19 of the host computer 7. Accordingly, at step S3-11, the data server module 25 receives a request for content data from the AV application 23 executing on the host computer 2, via the data bus interface 9a and network card driver module 15. In response, the data server module 25 may instruct the AV data processing module 27 to access and retrieve, at step S3-13, AV content data from a connected AV source device 17, via the external device interface 31.

[0030] Optionally, the AV data processing module 29 may he configured to perform one or more processing functions on the captured analogue or digital AV content data.

at step 53-1 5. before the captured AV content data is passed on to the data server module 25 and the network card driver module 15. This may include, but not be limited to, a wide array of typical AV processing functions such as colour balancing, scaling, watermarking, compression or encryption. On the other hand, the AV data processing module 29 may be configured to pass on the raw and unprocessed (e.g. uncompressed) AV signal as captured from the external AV source device 27, to the data server module 25.

[0031] At step 53-17, the AV content data is formatted based on the defined communication protocols implemented by the data server module 25. As mentioned above, in this exemplary embodiment, the data server module 25 formats the captured AV content data into response data for responding to the REST or HTTP requests. At step S3-19, the response data is then formatted by the network card driver module 15 into network-formatted data for transmission to the host computer 7 based on the defined network/transport protocols. In this exemplary embodiment, the network card driver module 15 formats the response data into IP packets, as is well known in the art. each IP packet including a payload portion including a portion of the captured AV content data as formatted by the data server module 25, and a header portion identifying the AV application 23 as the destination for the associated payload.

[0032] At step S3-21, the network card driver module 15 of the AV-network card 3 transmits the AV content data encapsulated in the defined network/transport protocol to the host computer 7, via the data bus interface 9. At step S3-23, the network-formatted data packets are received and processed, at step S3-25, by the operating system 19 on the host computer 7 to de-packetise the received data and retrieve the response data including the AV content data portions from the respective payloads of each received data packet, identify the AV application 23 as the destination for the retrieved data, and pass the retrieved AV content data to the AV application 23 for subsequent processing.

Advantages [0033] A number of advantages will be understood from the above description of the embodiments of the present invention.

[0034] In particular, the novel network AV capture card facilitates efficient development and provisioning of software applications that require AV capture into a computation environment software applications, and enables requirements for form factor and build quality to be met when installing such a system into host AV computing workflows.

Alternative Embodiments [0035] It will he understood that embodiments of the present invention are described herein by way of example only, and that various changes and modifications may be made without departing from the scope of the invention.

[0036] For example, in the embodiment described above, the AV-network card has a form factor of an expansion card for connection to a typical expansion slot of a host computer 7. As those skilled in the art will appreciate, the components, modules and functionality of the AV-network card may instead be provided as an external device that is connected as a network adapter to a data bus of the host computer, such as USB, Firewire, Thunderbolt, etc., via a physical connection port.

[0037] In the embodiment described above, an AV application on the host. computer receives and processes the captured content from the AV-network card. As those skilled in the art will appreciate, the host computer may instead or additionally he configured to act as a gateway, and transparently route the network-formatted data received from the AV-network card on to another network device connected via another network interface.

[0038] In the embodiment described above, the AV-network card comprises a plurality of modules, which when executed, enable the device to implement embodiments of the present invention as discussed herein. As those skilled in the art will appreciate, the modules may he implemented as computer programs, code, instructions or software may be stored in a computer program product and loaded into a memory of the AV-network card using any known instrument, such as removable storage disk or drive, hard disk drive, or communication interface, to provide some examples. Alternative embodiments may he implemented as control logic in hardware, firmware, or software or any combination thereof.

[0039] Yet further alternative embodiments may be envisaged, which nevertheless fall within the scope of the following claims. The term "includes", as employed in the detailed description or the claims, is intended to be inclusive in a manner similar to the term "comprising" as that term is interpreted when employed as a transitional word in a claim.

Claims

CLAIMS1. A device for connection to an expansion slot of a host computer, the device comprising: a host computer interface configured to communicate data as a network card on a data bus of the host computer; an external device interface configured to receive content data from a connected audio/visual device; a server module configured to provide received content data to the host computer as a network resource; and a network card driver module configured to format the received content data into network-formatted content data based on a predefined network protocol and to transmit the network-formatted content data to the host computer via the host computer interface.
2. The device of claim 1, wherein the host computer interface comprises a standard data bus connector and is configured to communicate data as a network card on a standard data bus of the host computer.
3. The device of claim 2, wherein the standard data bus is a USB bus, or a PCI-or PCMCIA-based bus.
4. The device of any preceding claim, wherein the external device interface comprises one or more connectors having a respective connector type.
5. The device of claim 4, wherein the external device interface is configured to receive content data from the audio/visual device using a standard data communication protocol.
6. The device of claim 5, wherein the audio/visual device is a camera.
7. The device of any preceding claim, wherein the server module is configured to respond to a request for data from an application executed on the host computer via an application layer protocol.
8. The device of any preceding claim, further comprising a signal processing module configured to perform one or more of analogue to digital conversion, filtering, decoding, encoding, re-encoding, compression, encryption, colour balancing, scaling and watermarking of the received content data.
9. The device of any preceding claim, wherein the formatting module is configured to format the content data into Internet Protocol data packets.
10. The device of any preceding claim, wherein the AV-network card is configured as a generic network card supported by a driver on the host computer, identified by a network card identifier stored in a read-only memory.
11. An apparatus for capturing multimedia signals from a connected device and transmitting the captured signals to a computer system as network-formatted data through a network card driver.
12. A method for capturing and providing content data by a peripheral device connected to a host computer as a network adapter, the method comprising the peripheral device: receiving content data from a connected audio/visual device; formatting the received content data into network-formatted content data based on a predefined network protocol; and transmitting the network-formatted content data to the host computer via a host computer interface.
13. A storage medium comprising machine-readable instructions stored thereon for causing a device to become configured as the device in accordance with any one of claims 1 to 10.
14. An expansion card substantially as hcreinbefore described with reference to, or as illustrated in Figure 1 and 2 of the accompanying drawings.
15. A multimedia data capture system as hereinbefore described with reference to, or as illustrated in Figure 1 of the accompanying drawings.
16. A method substantially as hereinbefore described with reference to, or as illustrated in Figure 3 of the accompanying drawings.