JVC 4ch Network Encoder VN-E4 - Manual (Page 70)

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7. API for Audio Receiving by VN-E4 _
7.2. Audio Receiving via RTP
1) The client establishes a TCP connection to port number 80 and sends out API.
Refer to Section 4 on details of the Accept and Authorization lines.
The API format when specifying using GET is as follows.
/api/receive?from=network&from.ip=data1&from.protocol=udp&from.session_id
=data2&from.ip_translate=on&to=audio
Example /api/receive?from=network&from.ip=10.0.0.100&from.protocol=udp&from.
session_id=12345678&from.ip_translate=on&to=audio
Specify the source IP address for ip=. Specify the client IP number for session_id=. VN-E4 will register this
number and accept the client with the same API (stop). VN-E4 will accept the API at all times when it is
specified as session_id=*.
When from.ip_translate is set to off, VN-E4 will standby to receive audio data from the IP address specified at
from.ip. When from.ip_translate is set to on, VN-E4 will ignore from.ip and standby to receive audio data from
the source IP address of this API.
2) VN-E4 returns a response.
HTTP/1.1 200 OK<CRLF>
Date: Fri, 13 MAY 2005 07:33:12 GMT<CRLF>
Server: VN-E4 API Server/1.0.0<CRLF>
Connection: Keep-Alive<CRLF>
content-type: text/plain<CRLF>
Connection: Keep-Alive<CRLF>
Keep-Alive: timeout=5, max=5<CRLF>
x-vne4_response:
from=network&from.ip=10.0.0.100&from.protocol=udp&from.session_id=1234567
8&from.ip_translate=on&to=audio<CRLF><CRLF>
200 OK<CRLF>
The client may disconnect TCP80 at this point of time.
3) The client continues to send 512 bytes of u-Law data with a 12-byte header to port number 49200.
The data's header format is as follows. The 12-byte RTP header is made up of 3 4-byte data. Refer to RFC1889
for details on the RTP header.
4) To end, send an API for stopping transmissions.
API Format /api/stop?from.session_id=data
Example /api/stop?from.session_id=*
Specify session_id= using the number that is specified via the send command. Ensure to stop audio reception
when session_id=* is specified.
Ⅵ Restrictions on Number of Clients
Only 1 client is allowed to send audio data to VN-E4. VN-E4 will return an error for this API and TCP will be
disconnected when this function is currently in use by another client. In addition, VN-E4 will also return an error for this
API and disconnect TCP when there exists a client that makes use of the audio reception feature at VN-E4 via RTP/UDP.
Ⅵ Timing of Data Sending
512 bytes, or in other words, 64 msec of audio data may be sent during each transmission. Send audio data at intervals
as evenly as possible. A part of the data may be lost if audio data exceeding 2 seconds are sent to VN-E4 at one time.
7.2. Audio Receiving via RTP
GET Space API Character String Space HTTP/1.1 0x0D 0x0A
Accept Space text/plain or text/html 0x0D 0x0A
Host: Space IP Address of VN-E4 0x0D 0x0A
Authorization: Basic Space User Name and Password 0x0D 0x0A 0x0D 0x0A
0x8000 Sequence No.
Time stamp (Unit: 8 kHz)
SSRC
512 bytes of u-Law data