KLV encoder / decoder library for STANAG 4609

Transcription

1 KLV (Key-Length-Value) is a data encoding standard used for binary data byte-packing and metadata embedding into video feeds. KLV encoder/decoder C++ library (available for both Windows and Linux) allows seamless integration at the encoding/streaming side, while KLV decoder module (available also as Direct Show KLV decoder filter or C# module ) may be used at the client side for data extraction. When used with optional MISB 0601 converter module, KLV decoder translates received data according to the EG0601 standard and provides a list of parsed and converted KLV items with corresponding timing information. KLV (Key-Length-Value) is a byte-level data encoding standard used for binary data byte-packing and metadata embedding into video feeds. Data is encoded into the K ey- L ength- V alue triplets, where K ey identifies the data, 1 / 10

2 L ength specifies the data's length, and V alue is the data itself. It is defined in SMPTE 336M-2007 (Data Encoding Protocol Using Key-Length Value), approved by the Society of Motion Picture and Television Engineers. A KLV encoding protocol defines a data structure which is independent of the application or transportation method used. The KLV encoder C++ library (A.Net wrapper is available upon request) allows seamless integration at the encoding/streaming side, while KLV decoder module ( available also as Direct Show KLV decoder filter or C# module ) may be used on the client side for extraction of encoded data. When used with optional MISB 0601 converter module, KLV decoder translates received data according to the MISB 0601.X standard and provides a list of parsed and converted KLV items with corresponding timing information. {xtypo_alert}klv lib and STANAG4609Lib have been specially designed to deal with STANAG 4609 standard and contain numerous helper functions and converters to facilitate LDS and UDS metadata sets creation, Big Endian swap, etc. {/xty po_alert} {xtypo_sticky} "ITAR-free" {/xtypo_sticky} 2 / 10

3 The MPEG-2 Transport Stream provides an infrastructure for the carriage of video, audio and metadata in a single motion imagery stream as shown below. 3 / 10

4 STANAG 4609 STANAG 4609 is intended to provide common methods for exchange of motion imagery across systems within and among NATO nations. It provides a guidance on uncompressed, compressed, and related motion imagery sampling structures; motion imagery time standards, motion imagery metadata standards, interconnections, and common language descriptions of motion imagery system parameters. Unmanned Air Systems use two types of KLV encoded metadata. Universal Data Set (UDS) - the 16-byte key, basic encoding rules (BER) formatted length, and the data value is appropriate for applications where bandwidth isn't a concern. However, transmitting the 16-byte universal key quickly uses up the available bandwidth. UAS airborne platforms use a wireless communications channel where the bandwidth for metadata is limited. Because of the bandwidth disadvantages of using a Universal Data Set, it is more desirable to use a Local Data Set for transmission over a UAS Datalink. Local Data Set can use a 1, 2 or 4-byte key with a 1, 2, 4-byte, or BER encoded length. For more info about KLV use in UAS application see ref pageuseinuav Used in both military and civil applications, the KLV lib allows developers to create applications that receive streaming video coming from UAV platforms, extract the telemetry and other metadata (KLV format, for example EG 0601.X) process it in real time or archive for later retrieval. KlvLib supports processing of Compound items (sets, packs). {xtypo_alert} Check out our new STANAG Stream Recorder / KLV metadata analyzer tool b 4 / 10

5 uilt on top of KLV Lib {/xtypo_alert} KLV encoded metadata in MPEG Transport streams. Read more on how video and KLV encoded metadata can be synchronously transported in MPEG Transport streams according to STANAG KLVLib makes it easy to encode or decode the KLV data. Below is the hypothetical example MMS data packets (ISB Standards , , and SMPTE 336M-2007), as described in EG0902. {xtypo_warning} All values are shown for illustration purposes only!{/xtypo_warning} 5 / 10

6 The TLV bytes are appended end-to-end, and together become the value portion of the enclosing KLV packet. In this example, there are 97 bytes of TLV data - this is encoded as the length of the KLV packet. The whole local set starts with the 16 byte UL key, followed by the length 0x61, followed by all the TLV hex bytes above in order. In hex, the whole example KLV packet is: 6 / 10

7 {xtypo_warning} significant bit You the. KlvInspector (msb) MISB easily first. EG0909 byte analyze (MSB) All sample metadata is low first. level Bytes {/xtypo_warning} shall imported KLV shall be data represented into be using big-endian KlvInspector using bit big-endian encoding tool. Here encoding, with is the a screencapture most i.e. the significant mostof 7 / 10

8 Below is a sequence diagram for encoding the above Metadata using KLVLib 8 / 10

9 Sequence diagram that describes decoding of Metadata using KLVLib 9 / 10

10 To used: First, {codecitation // IKlvEncoder* klvencoder->setouterkey("060e2b34020b01010e "); encode/decode Create create outer STANAG and class=")" key. initialize the We 4609 width=""} above use = an KLV CreateKlvEncoder(); ASCII instance sample encoder string of MMS KLV for data this Encoder: example packets the following simple code may be {/codecitation} Next, {codecitation {0x00,0x04,0x60,0x50,0x58,0x4E,0x01,0x80}; // klvencoder->setchecksumkey("01"); checksum KLV A width=""} timestamp. Items: key char unsigned Mon key 05 Jan = int64 short 2; val_16 val_64 22:08:22 = 0x71C2; = Heading Unix ; (UTC) val_64); Time Angle 00 Stamp 04 0x71C2-50 Microseconds // 58 After 4E 01 endian L = swap 8. Key 5; 06 Platform Pitch 0xFD3D Degrees - // val_16 key klvencoder->addklvitem(key,.{/codecitation}.. Key = 6; 7; = 07 0xFD3D; 0x08B8; Platform Roll val_16); Angle 0x08B Degrees Degrees Next, {codecitation pencchunk if( { memcpy(klvbuffer, } Do encodedlength Use something the = and results width=""} KLV klvencoder->encode(encodedlength); with return ) Items pencchunk, the an data and encoded put encodedlength); the byte result array into buffer delete {/codecitation} Another {codecitation IKlvDecoder* 9. Delete klvencoder; example. the KlvEncoder previously and deallocate encoded memory // if( encodedlength IKlvItem** char klvdecoder->parse(iklvitem::sixteen_bytes, itemcount; Create valuestr[256]; the STANAG width=""} buffer )) that 4609 klvdecoder->getitemlist(itemcount); contains = KLV CreateKlvDecoder(); decoder encoded buffer dataand IKlvItem::ONE_BYTE, create a list of Klv klvbuffer, Items { const unsigned for(int sprintf(valuestr cout } length char* i i=0; = 0; = char* i<length; itemarray[i]->getlength(); keystr i < itemcount; value + i*2, = i++) itemarray[i]->getkeystring(); "%02X", = (unsigned i++) //3. delete {/codecitation} Delete << klvdecoder; keystr KLV << Decoder ": Ox" << *(value+i)); valuestr char* << )itemarray[i]->getvalue(); Here is a complete sample code ( LDS ) / ( endl; Please {xtypo_download} version can {/xtypo_download} see an online KLV documentation Lib Available for as more C/C++ UDS details. ) library. KLV A You (installed self-explanatory. standards. The {phocadownload freely demo can Lib (for at is evaluate library Windows).Net a C:Program C++ wrapper It view=file id=1 text=klvlibdemo.zip target=s} is encodes the library the fully evaluation software FilesImpleoTvKLV functional, is (available and before then copy but decodes upon of making has Windows) the LibKlvTestAp) request. 10 KLV back min a purchase. per It some ( includes C++). session Please which sample decision. There both limitation. register data pretty KLV a given simple encoder to much download in. test This one and application way of the decoder. the you Demo Buy Here licenses DEVELOPER * Developer Small Corporate KLV is the Licenses Lib Business pricing SDK licenses License information License EUR Small (royalty-free, 31 unlimited nontransferable, Business personal, nontransferable, library includes nonexclusive, EUR Corporate both nonexclusive, encoder royalty free and royalty-free DEVELOPER decoder EUR ): license Delivery {xtypo_info}please help with will the be integration. done do (through not hesitate ) within to contact {/xtypo_info} 24 hours us should after you you place have your any order. questions or need 10 / 10