5
votes

I have network IP camera(Canon VB-M40). This camera support ONVIF protocol. I am implementing its ONVIF functionality in windows using C language. I got its RTSP URI using following request.

snprintf(postData, sizeof(postData),
      "<?xml version=\"1.0\" encoding=\"utf-8\"?>"
      "<soap:Envelope xmlns:soap=\"http://www.w3.org/2003/05/soap-envelope\" "
      "xmlns:tds=\"http://www.onvif.org/ver10/media/wsdl\""
      "xmlns:tt=\"http://www.onvif.org/ver10/schema\">"             
      "<soap:Body>"
      "<tds:GetStreamUri>"
        "<tds:StreamSetup>"
          "<tt:Stream>0</tt:Stream>" 
          "<tt:Transport>" 
            "<tt:Protocol>HTTP</tt:Protocol>" 
          "</tt:Transport>"
        "</tds:StreamSetup>"
        "<tds:ProfileToken>profile1</tds:ProfileToken>"
      "</tds:GetStreamUri>"
        "</soap:Body></soap:Envelope>",
      username, digest_str, nonce_str, time_str); 

and the response is:

<?xml version="1.0" encoding="UTF-8"?>
<SOAP-ENV:Envelope  xmlns:SOAP-ENV="http://www.w3.org/2003/05/soap-envelope" 
                    xmlns:SOAP-ENC="http://www.w3.org/2003/05/soap-encoding" 
                    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
                    xmlns:xsd="http://www.w3.org/2001/XMLSchema" 
                    xmlns:wsa5="http://www.w3.org/2005/08/addressing" 
                    xmlns:c14n="http://www.w3.org/2001/10/xml-exc-c14n#" 
                    xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd" 
                    xmlns:ds="http://www.w3.org/2000/09/xmldsig#" 
                    xmlns:wsse="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd" 
                    xmlns:MC2="http://www.onvif.org/ver10/schema" 
                    xmlns:MC3="http://www.w3.org/2005/05/xmlmime" 
                    xmlns:MC4="http://docs.oasis-open.org/wsn/b-2" 
                    xmlns:MC10="http://www.w3.org/2004/08/xop/include" 
                    xmlns:MC5="http://docs.oasis-open.org/wsrf/bf-2" 
                    xmlns:MC6="http://docs.oasis-open.org/wsn/t-1" 
                    xmlns:CC="http://www.canon.com/ns/networkcamera/onvif/va/schema" 
                    xmlns:MC1="http://www.onvif.org/ver10/media/wsdl" 
                    xmlns:MC8="http://www.onvif.org/ver20/analytics/wsdl/RuleEngineBinding" 
                    xmlns:MC9="http://www.onvif.org/ver20/analytics/wsdl/AnalyticsEngineBinding" 
                    xmlns:MC7="http://www.onvif.org/ver20/analytics/wsdl" 
                    xmlns:ter="http://www.onvif.org/ver10/error" 
                    xmlns:wsnt="http://docs.oasis-open.org/wsn/b-2" 
                    xmlns:tns1="http://www.onvif.org/ver10/topics">
    <SOAP-ENV:Header></SOAP-ENV:Header>
    <SOAP-ENV:Body>
        <MC1:GetStreamUriResponse>
            <MC1:MediaUri>
                <MC2:Uri>rtsp://192.168.5.53:8090/profile1=r</MC2:Uri>
                <MC2:InvalidAfterConnect>false</MC2:InvalidAfterConnect>
                <MC2:InvalidAfterReboot>true</MC2:InvalidAfterReboot>
                <MC2:Timeout>PT0M0S</MC2:Timeout>
            </MC1:MediaUri>
        </MC1:GetStreamUriResponse>
    </SOAP-ENV:Body>
</SOAP-ENV:Envelope>

according to ONVIF specification, once I get the stream URI I should send 'DESCRIBE' request to the device. I am using this procedure because I need stream on TCP.

My question is how to send 'DESCRIBE' request to the Device and on which socket?

Should I send this request on the same socket on which I sent GetStreamURI request. Or I have to create an other one. And what will be the format of the request?

1

1 Answers

3
votes

Send it to the same host as GetStreamUri request on port 554 (or other port configured in the device for RTSP). Then you have to send OPTIONS request before DESCRIBE. It will probably return 401 Unauthorized status and nonce + realm value in its body. (I am using diferent address then you recieved in your GetStreamUri response.)

Request:
OPTIONS http://192.168.128.99:80/profile1/media.smp RTSP/1.0\r\n
CSeq: 1\r\n
User-Agent: MyAgent\r\n\r\n

Response:
RTSP/1.0 401 Unauthorized
CSeq: 1
Date: Thu Jun 28 05:39:55 2012 GMT
Expires: Thu Jun 28 05:39:55 2012 GMT
Cache-Control: must-revalidate
WWW-Authenticate: Digest realm="iPOLiS", nonce="00000000000000000000000048E02F14"

Read this realm and nonce values, because you need it for autorization and send another, authorized OPTIONS request.

OPTIONS http://192.168.128.99:80/profile1/media.smp RTSP/1.0\r\n
CSeq: 2\r\n
Authorization: Digest username="admin", realm="iPOLiS", nonce="00000000000000000000000048E02F14", uri="http://192.168.128.99:80/profile1/media.smp", response="23a5a81fb98b6cb29368eba060ba31b9"\r\n
User-Agent: MyAgent\r\n\r\n

Response is generate this way

Then come DESCRIBE request

DESCRIBE http://192.168.128.99:80/profile1/media.smp RTSP/1.0\r\n
CSeq: 3\r\n
User-Agent: MyAgent\r\n\r\n

and response

RTSP/1.0 200 OK
CSeq: 3
Date: Thu Jun 28 05:46:20 2012 GMT
Expires: Thu Jun 28 05:46:20 2012 GMT
Content-Base: http://192.168.128.99:554/profile1/media.smp/
Content-Type: application/sdp
Content-Length: 498
x-Accept-Retransmit: our-retransmit
x-Accept-Dynamic-Rate: 1
Cache-Control: must-revalidate

v=0
o=- 0 0 IN IP4 192.168.128.9
s=Media Presentation
i=samsung
c=IN IP4 0.0.0.0
b=AS:384128
t=0 0
a=control:http://192.168.128.99:554/profile1/media.smp
a=range:npt=now-
m=video 40336 RTP/AVP 26
b=AS:384000
a=rtpmap:26 JPEG/90000
a=control:http://192.168.128.99:554/profile1/media.smp/trackID=v
a=cliprect:0,0,768,1024
a=framesize:26 1024-768
a=framerate:5.0
m=audio 40338 RTP/AVP 0
b=AS:64
a=rtpmap:0 PCMU/8000
a=control:http://192.168.128.99:554/profile1/media.smp/trackID=a

from this response address in a=control:http://192.168.128.99:554/profile1/media.smp/trackID=v should be parsed for media m=video (its a SDP protocol). Thats how far did i get. Next procedure should be to make SETUP request with transport information and then send PLAY request. You must listen on the port you specified in SETUP request to recieve images.