From 4bfd864f10b68b71482b35c818559068ef8d5797 Mon Sep 17 00:00:00 2001 From: Thomas Voss Date: Wed, 27 Nov 2024 20:54:24 +0100 Subject: doc: Add RFC documents --- doc/rfc/rfc978.txt | 290 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 290 insertions(+) create mode 100644 doc/rfc/rfc978.txt (limited to 'doc/rfc/rfc978.txt') diff --git a/doc/rfc/rfc978.txt b/doc/rfc/rfc978.txt new file mode 100644 index 0000000..977daf6 --- /dev/null +++ b/doc/rfc/rfc978.txt @@ -0,0 +1,290 @@ + + + Network Working Group J. K. Reynolds (ISI) + Request for Comments: 978 R. Gillmann (Inner Loop) + W. A. Brackenridge (Alembic) + A. Witkowski (Inner Loop) + J. Postel (ISI) + February 1986 + + + VOICE FILE INTERCHANGE PROTOCOL (VFIP) + + +STATUS OF THIS MEMO + + This memo describes a proposed voice file interchange format for use + in the ARPA-Internet community. Suggestions for improvement are + encouraged. Distribution of this memo is unlimited. + +1. INTRODUCTION + + The purpose of the Voice File Interchange Protocol (VFIP) is to + permit the interchange of various types of speech files between + different systems. Currently, there are many different types of + voice implementations, but no specific standard has been set with an + eye towards compatability between these systems. With the increasing + interest and development of voice, specifically in Multimedia Mail, + there is an increased need to include standardized speech into a + common data structure. + + The Voice File Interchange Protocol defines a header to describe the + voice data. The 18-byte header contains the identifier, the header + version number, the header length, a DTMF mask for Touch-Tones, the + recording rate in bits per second, the total time in deci-seconds + (tenths of a second), and the encoding/recording method (see + Figure 1). + +2. THE VOICE FILE INTERCHANGE PROTOCOL HEADER + + The Voice File Interchange Protocol header is organized as follows: + + 2.1 The Header Version Number + + The version number is 1-byte. This first version is number one. + + 2.2 The Header Length + + The length is a 1-byte field indicating the length of the entire + header in bytes. For this first version, the length is + 18 (bytes). + + + + + + +Reynolds, et al. [Page 1] + + + +Voice File Interchange Protocol RFC 978 + + + 2.3 The DTMF Mask + + This field describes what is known about DTMF Touch-Tones in the + data. The field consists of a 16 flag bits which indicate what is + known about particular DTMF tones. The 16 possible DTMF tones, in + order, are: 0 1 2 3 4 5 6 7 8 9 # * A B C D. The low order bit + of the field is tone 0. + + A 1-bit signifies that the corresponding tone is guaranteed NOT to + be in the speech file. A 0-bit signifies that it may or may not + be in the speech file. Therefore, a field of 16 zeros denotes + that nothing is known about the tones. A field of 16 ones denotes + that there are no tones in the file. + + 2.4 Recording Rate + + The recording rate is a 32-bit field and is the approximate rate + in bits/second of the method used to record the speech. For + variable rate methods, this may be very approximate. + + 2.5 Total Time + + A 32-bit number indicating the total time of the recording in + deci-seconds. For example, 600 indicates 1 minute of speech. + + 2.6 Methods of Encoding/Recording + + This 6-byte ASCII field indicates the method of + encoding/recording. Names shorter than six characters are padded + out to the right with blanks (the ASCII space character, code 32 + decimal). For comparisons, the names are case insensitive. + + Some known methods of Encoding/Recording are: + + TI - The Texas Instruments card for the IBM PC [5]. + + IBM - PC Voice Communications Options. + + NVP-1 and NVP-2 - Network Voice Protocol [1,2]. + + COMPUT - Computalker card for the IBM PC [4]. + + + + + + + + + + +Reynolds, et al. [Page 2] + + + +Voice File Interchange Protocol RFC 978 + + +3. SUMMARY + + This 18-byte header will permit interchange of speech files between + different systems, as well as facilitate automatic conversion between + formats. The header does not have to be prepended to the speech file + proper; it may be in the form of a separate associated file, if that + is more convenient. + + <------------16-bits------------> + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Version | Length | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | -DTMF- | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | -Recording- | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | -Rate- | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | -Total- | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | -Time- | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | M | E | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | T | H | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | O | D | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Figure 1 + + + + + + + + + + + + + + + + + + + + + +Reynolds, et al. [Page 3] + + + +Voice File Interchange Protocol RFC 978 + + +4. EXAMPLES + + Example 1 is for one minute of 2400 bps NVP-2 speech. Nothing is + known about DTMF tones in the data. + + <------------16-bits------------> + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | 1 | 18 | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | 0 | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | 2400 | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | 600 | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | N | V | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | P | - | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | 2 | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Example 1 + + + + + + + + + + + + + + + + + + + + + + + + +Reynolds, et al. [Page 4] + + + +Voice File Interchange Protocol RFC 978 + + + Example 2 shows the header for 10 seconds of 1200 bps TI speech, with + none of the DTMF tone 0-9 in the data, but no information about + tones *, #, A-D. + + <------------16-bits------------> + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | 1 | 18 | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | 1023 | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | 1200 | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | 100 | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | T | I | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Example 2 + +REFERENCES + + [1] Cohen, Danny, "Specifications for the Network Voice Protocol + (NVP)", RFC 741 (NIC 42444), USC/Information Sciences Institute, + January 1976. + + [2] Cohen, Danny, "A Network Voice Protocol (NVP-II)", + USC/Information Sciences Institute, April 1981. + + [3] O'Leary, G. C., "Local Access Area Facilities for Packet Voice", + MIT/LL, October 1980. + + [4] Computalker, "Compu Phone for the IBM PC/XT", Santa Monica, + California, August 1985. + + [5] Texas Instruments, Inc., "The TI Speech Application Tool Kit + Guide", TI Part #2232384-1, May 1985. + + + + + + + +Reynolds, et al. [Page 5] + -- cgit v1.2.3