ref: 4468c75adbefed247ae592e42549da544f468277
parent: ed8e1b49370e39b776930918e5d5f7d6408c1a3c
author: Jean-Marc Valin <[email protected]>
date: Thu Jul 8 09:40:07 EDT 2010
draft update, instructions
--- a/INSTALL
+++ b/INSTALL
@@ -1,0 +1,1 @@
+See README file for details
--- a/README
+++ b/README
@@ -1,20 +1,36 @@
-This is a prototype codec and for now it doesn't do anything useful. To get
-the celt and silk submodules, you need to do:
+This is a prototype codec and for now it has limited functionality.
-% git submodule init
-% git submodule update
+To build from a distribution tarball, you only need to do the following:
-Compiling is currently tricky. You first need to configure the CELT directory:
+% ./configure --disable-shared
+% make
-% cd celt
+To build from the git repository, the following steps are necessary
+
+0) Clone the repository:
+
+% git clone git://git.xiph.org/users/jm/ietfcodec.git
+% cd ietfcodec
+
+1) Get the celt and silk submodules:
+
+% git submodule update --init
+
+2) Compiling
+
% ./autogen.sh
% ./configure --disable-shared
-% cd ..
+% make
-Then you can use the top-level Makefile by typing:
-% make
+Once you have compiled the codec, there will be a test_hybrid executable in
+the src/ directory. This can be in the following way:
-If you're lucky, then everything works. Most likely there will be an error in
-one of the paths that are hardcoded into one of the makefiles. This should
-improve in the future.
+% ./test_hybrid 48000 1 960 80 input.sw output.sw
+
+The arguments are:
+1) The sampling rate (only 48000 supported for now)
+2) The number of channels (only mono supported for now)
+3) The frame size in samples (480 and 960 supported)
+4) Input PCM file (16-bit, machine endian)
+5) Output PCM file after encoding and decoding (16-bit machine endian)
--- a/configure.ac
+++ b/configure.ac
@@ -3,7 +3,7 @@
AC_PREREQ([2.59])
AC_INIT(src/hybrid.h)
-AM_INIT_AUTOMAKE(libietfcodec,0.0.0)
+AM_INIT_AUTOMAKE(ietfcodec,20100708)
# Checks for programs.
AC_PROG_CC
--- a/doc/draft-valin-codec-prototype.xml
+++ b/doc/draft-valin-codec-prototype.xml
@@ -2,7 +2,7 @@
<!DOCTYPE rfc SYSTEM 'rfc2629.dtd'>
<?rfc toc="yes" symrefs="yes" ?>
-<rfc ipr="trust200902" category="std" docName="draft-valin-codec-prototype-00">
+<rfc ipr="trust200902" category="std" docName="draft-valin-codec-prototype-01">
<front>
<title abbrev="Codec Prototype">Prototype for IETF Interactive Audio Codec</title>
@@ -39,7 +39,7 @@
</author>
-<date day="5" month="July" year="2010" />
+<date day="8" month="July" year="2010" />
<area>General</area>
@@ -107,6 +107,17 @@
The main changes
include better support for 20 ms frames as well as the ability to encode
only the higher bands using a range coder partially filled by the SILK layer.</t>
+
+<t>
+In addition to their frame size, the SILK and CELT codecs require
+a look-ahead of 5.2 ms and 2.5 ms, respectively. SILK's look-ahead is due to
+noise shaping estimation (5 ms) and the internal resampling (0.2 ms), while
+CELT's look-ahead is due to the overlapping MDCT windows. To compensate for the
+difference, the CELT encoder input is delayed by 2.7 ms. This ensures that low
+frequencies and high frequencies arrive at the same time.
+</t>
+
+
<section title="Source Code">
<t>
The source code is currently available in a
@@ -284,7 +295,10 @@
audio stream must not cause the encoder to misbehave because this would
allow an attacker to attack transcoding gateways.
</t>
-
+<t>
+In its current version, this prototype codec likely does NOT meet these
+security considerations, so it should be used with caution.
+</t>
</section>
@@ -294,12 +308,12 @@
</t>
</section>
-<!--
<section anchor="Acknowledgments" title="Acknowledgments">
<t>
+Thanks to all other developers, including Soeren Skak Jensen, Gregory Maxwell,
+Christopher Montgomery, Karsten Vandborg Soerensen, and Timothy Terriberry.
</t>
</section>
--->
</middle>