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• Build libaacplus 2.0.2 for ios

  23 mai 2013, par Javan

  Does anyone build libaacplus2.0.2(Download here) successed for iOS ? I want ffmpeg support that.It cast me one day to build that, but failed.

  This is libaacplus2.0.2/autogen.sh， It was edited, just let it create configure file :

  #!/bin/sh
  
  # Run this to set up the build system: configure, makefiles, etc.
  
  # (based on the version in enlightenment's cvs)
  
  
  
  package="libaacplus"
  
  
  
  srcdir=`dirname $0`
  
  test -z "$srcdir" && srcdir=.
  
  
  
  cd "$srcdir"
  
  DIE=0
  
  
  
  (autoheader --version) < /dev/null > /dev/null 2>&1 || {
  
      echo
  
      echo "You must have autoconf installed to compile $package."
  
      echo "Download the appropriate package for your distribution,"
  
      echo "or get the source tarball at ftp://ftp.gnu.org/pub/gnu/"
  
      DIE=1
  
  }
  
  
  
  (autoreconf --version) < /dev/null > /dev/null 2>&1 || {
  
      echo
  
      echo "You must have autoreconf installed to compile $package."
  
      echo "Download the appropriate package for your distribution,"
  
      echo "or get the source tarball at ftp://ftp.gnu.org/pub/gnu/"
  
      DIE=1
  
  }
  
  
  
  (automake --version) < /dev/null > /dev/null 2>&1 || {
  
      echo
  
      echo "You must have automake installed to compile $package."
  
      echo "Download the appropriate package for your system,"
  
      echo "or get the source from one of the GNU ftp sites"
  
      echo "listed in http://www.gnu.org/order/ftp.html"
  
      DIE=1
  
  }
  
  
  
  if test "$DIE" -eq 1; then
  
      exit 1
  
  fi
  
  
  
  if test -z "$*"; then
  
      echo "I am going to run ./configure with no arguments - if you wish "
  
      echo "to pass any to it, please specify them on the $0 command line."
  
  fi
  
  
  
  echo "Generating configuration files for $package, please wait...."
  
  
  
  echo "  aclocal $ACLOCAL_FLAGS"
  
  aclocal $ACLOCAL_FLAGS
  
  echo "  autoheader"
  
  autoheader
  
  echo "  libtoolize --automake"
  
  libtoolize --automake
  
  echo "  automake --add-missing $AUTOMAKE_FLAGS"
  
  automake --add-missing $AUTOMAKE_FLAGS 
  
  echo "  autoreconf"
  
  autoreconf
  
  
  
  #$srcdir/configure "$@" && echo

  After run the autogen.sh script :

  ./autogen.sh

  the configure file has been created in the same path, them i re-compressed the libaacplus folder named with "libaacplus-2.0.2.tar.gz". Bellow is build script(build-libaacplus.sh) wrote by me :

  #!/bin/bash
  
  
  
  SRC_PACK='libaacplus-2.0.2.tar.gz'
  
  
  
  SRC_ROOT=`pwd`/libaacplus-2.0.2
  
  BUILD_PATH=`pwd`/build
  
  
  
  DEVELOPER_ROOT='/Applications/Xcode.app/Contents/Developer'
  
  IOS_VERSION='6.1'
  
  #CC="$DEVELOPER_ROOT/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang"
  
  
  
  CPU_CORE_COUNT=`sysctl -n machdep.cpu.core_count` #Check cpu core number
  
  MAKE_JOBS=$CPU_CORE_COUNT+1
  
  
  
  function build_with_args() {
  
      local arch=$1
  
      local platform=$2
  
      local host=$3
  
      local cc=$4
  
      local build=$5
  
      local cpp=$6
  
      local ios_dev_root="$DEVELOPER_ROOT/Platforms/iPhone$platform.platform/Developer"
  
      local sys_root="$ios_dev_root/SDKs/iPhone$platform$IOS_VERSION.sdk"
  
  
  
      if [ -d $SRC_ROOT ]; then
  
          echo "Cleaning $SRC_ROOT ..."
  
          rm -rf $SRC_ROOT    
  
          echo "Clean $SRC_ROOT completed!"
  
      fi
  
  
  
      echo "Decompressing $SRC_PACK ..."
  
      tar -xzf $SRC_PACK
  
      echo "Decompress $SRC_PACK completed!"
  
  
  
      cd $SRC_ROOT
  
  
  
      export PATH="$ios_dev_root/usr/bin:$DEVELOPER_ROOT/usr/bin:$PATH"
  
      export CC=$cc
  
      export CFLAGS="-I$sys_root/usr/include" 
  
      export LDFLAGS="--sysroot=$sys_root -L$sys_root/usr/lib/ -L$sys_root/usr/lib/system"
  
      export CPPFLAGS=$CFLAGS
  
      export CPP=$cpp
  
      export TARGET=$build
  
  
  
      ./configure \
  
      --prefix="$BUILD_PATH/$arch" \
  
      --host=$host \
  
      --build=$build \
  
      --with-sysroot=$sys_root \
  
      --enable-shared \
  
      --enable-static 
  
  
  
      echo "Building for $arch ..."
  
  
  
  #   make -j$MAKE_JOBS
  
      make install
  
      make clean
  
  
  
      echo "Build for $arch completed!"
  
  
  
      cd -
  
  }
  
  
  
  function build_armv7() {
  
      local platform='OS'
  
      local bin_path="$DEVELOPER_ROOT/Platforms/iPhone$platform.platform/Developer/usr/bin"
  
      build_with_args \
  
          'armv7' \
  
          "$platform" \
  
          'arm' \
  
          "$bin_path/arm-apple-darwin10-llvm-gcc-4.2" \
  
          'arm-apple-darwin10' \
  
          "$bin_path/arm-apple-darwin10-llvm-g++-4.2"
  
  }
  
  
  
  function build_armv7s() {
  
      local platform='OS'
  
      local bin_path="$DEVELOPER_ROOT/Platforms/iPhone$platform.platform/Developer/usr/bin"
  
      build_with_args \
  
          'armv7s' \
  
          "$platform" \
  
          'arm' \
  
          "$bin_path/arm-apple-darwin10-llvm-gcc-4.2" \
  
          'arm-apple-darwin10' \
  
          "$bin_path/arm-apple-darwin10-llvm-g++-4.2"
  
  }
  
  
  
  function build_i386() {
  
      local platform='Simulator'
  
      local bin_path="$DEVELOPER_ROOT/Platforms/iPhone$platform.platform/Developer/usr/bin"
  
      build_with_args \
  
          'i386' \
  
          "$platform" \
  
          'i386' \
  
          "$bin_path/i686-apple-darwin11-llvm-gcc-4.2" \
  
          'i686-apple-darwin11' \
  
          "$bin_path/i686-apple-darwin11-llvm-g++-4.2"
  
  
  
  
  
  }
  
  
  
  if [ -d $BUILD_PATH ]; then
  
      echo "Cleaning $BUILD_PATH..."
  
      rm -rf $BUILD_PATH
  
  fi
  
  
  
  build_armv7
  
  #build_armv7s
  
  #build_i386
  
  
  
  echo '>>>>>>>>>>>>>>>>>All completed!<<<<<<<<<<<<<<'

  It failed again and again. Run script->failed->see config.log->modify->Run script ...

  I don't know what should I can do. Someone can help me ? Thanks a lot !
  The last config.log content is bellow :

  This file contains any messages produced by compilers while
  
  running configure, to aid debugging if configure makes a mistake.
  
  
  
  It was created by libaacplus configure 2.0.2, which was
  
  generated by GNU Autoconf 2.65.  Invocation command line was
  
  
  
    $ ./configure --prefix=/Users/md313/Documents/Developer/OpenSource/ffmpef4ios-build-scripts/external-libs/build/armv7 --host=arm --build=arm-apple-darwin10 --with-sysroot=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk --enable-shared --enable-static
  
  
  
  ## --------- ##
  
  ## Platform. ##
  
  ## --------- ##
  
  
  
  hostname = JieMacBookPro.local
  
  uname -m = x86_64
  
  uname -r = 11.4.2
  
  uname -s = Darwin
  
  uname -v = Darwin Kernel Version 11.4.2: Thu Aug 23 16:25:48 PDT 2012; root:xnu-1699.32.7~1/RELEASE_X86_64
  
  
  
  /usr/bin/uname -p = i386
  
  /bin/uname -X     = unknown
  
  
  
  /bin/arch              = unknown
  
  /usr/bin/arch -k       = unknown
  
  /usr/convex/getsysinfo = unknown
  
  /usr/bin/hostinfo      = Mach kernel version:
  
       Darwin Kernel Version 11.4.2: Thu Aug 23 16:25:48 PDT 2012; root:xnu-1699.32.7~1/RELEASE_X86_64
  
  Kernel configured for up to 4 processors.
  
  2 processors are physically available.
  
  4 processors are logically available.
  
  Processor type: i486 (Intel 80486)
  
  Processors active: 0 1 2 3
  
  Primary memory available: 4.00 gigabytes
  
  Default processor set: 127 tasks, 619 threads, 4 processors
  
  Load average: 0.97, Mach factor: 3.02
  
  /bin/machine           = unknown
  
  /usr/bin/oslevel       = unknown
  
  /bin/universe          = unknown
  
  
  
  PATH: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin
  
  PATH: /Applications/Xcode.app/Contents/Developer/usr/bin
  
  PATH: /opt/local/bin
  
  PATH: /opt/local/sbin
  
  PATH: /usr/bin
  
  PATH: /bin
  
  PATH: /usr/sbin
  
  PATH: /sbin
  
  PATH: /usr/local/bin
  
  PATH: /usr/X11/bin
  
  PATH: /Library/StartupItems/MySQLCOM
  
  PATH: /usr/local/mysql/bin
  
  
  
  
  
  ## ----------- ##
  
  ## Core tests. ##
  
  ## ----------- ##
  
  
  
  configure:2378: checking for a BSD-compatible install
  
  configure:2446: result: /usr/bin/install -c
  
  configure:2457: checking whether build environment is sane
  
  configure:2512: result: yes
  
  configure:2571: checking for arm-strip
  
  configure:2601: result: no
  
  configure:2611: checking for strip
  
  configure:2627: found /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/strip
  
  configure:2638: result: strip
  
  configure:2650: WARNING: using cross tools not prefixed with host triplet
  
  configure:2663: checking for a thread-safe mkdir -p
  
  configure:2702: result: ./install-sh -c -d
  
  configure:2715: checking for gawk
  
  configure:2745: result: no
  
  configure:2715: checking for mawk
  
  configure:2745: result: no
  
  configure:2715: checking for nawk
  
  configure:2745: result: no
  
  configure:2715: checking for awk
  
  configure:2731: found /usr/bin/awk
  
  configure:2742: result: awk
  
  configure:2753: checking whether make sets $(MAKE)
  
  configure:2775: result: yes
  
  configure:2868: checking for arm-gcc
  
  configure:2895: result: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2
  
  configure:3164: checking for C compiler version
  
  configure:3173: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2 --version >&5
  
  arm-apple-darwin10-llvm-gcc-4.2 (GCC) 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2410.2.00)
  
  Copyright (C) 2007 Free Software Foundation, Inc.
  
  This is free software; see the source for copying conditions.  There is NO
  
  warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  
  
  
  configure:3184: $? = 0
  
  configure:3173: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2 -v >&5
  
  Using built-in specs.
  
  Target: arm-apple-darwin10
  
  Configured with: /private/var/tmp/llvmgcc42_Embedded/llvmgcc42_Embedded-2410.2~111/src/configure --enable-checking --enable-werror --prefix=/Developer/usr/llvm-gcc-4.2 --mandir=/share/man --enable-languages=c,objc,c++,obj-c++ --program-prefix=llvm- --program-transform-name=/^[cg][^.-]*$/s/$/-4.2/ --with-slibdir=/usr/lib --disable-tls --build=i686-apple-darwin10 --enable-llvm=/private/var/tmp/llvmgcc42_Embedded/llvmgcc42_Embedded-2410.2~111/dst-llvmCore/Developer/usr/local --program-prefix=arm-apple-darwin10- --host=x86_64-apple-darwin10 --target=arm-apple-darwin10 --with-gxx-include-dir=/usr/include/c++/4.2.1 --with-build-sysroot=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.Internal.sdk
  
  Thread model: posix
  
  gcc version 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2410.2.00)
  
  configure:3184: $? = 0
  
  configure:3173: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2 -V >&5
  
  arm-apple-darwin10-llvm-gcc-4.2: '-V' option must have argument
  
  configure:3184: $? = 1
  
  configure:3173: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2 -qversion >&5
  
  arm-apple-darwin10-llvm-gcc-4.2: no input files
  
  configure:3184: $? = 1
  
  configure:3204: checking whether the C compiler works
  
  configure:3226: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2 -I/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include -I/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include --sysroot=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk -L/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/lib/ -L/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/lib/system conftest.c  >&5
  
  configure:3230: $? = 0
  
  configure:3279: result: yes
  
  configure:3282: checking for C compiler default output file name
  
  configure:3284: result: a.out
  
  configure:3290: checking for suffix of executables
  
  configure:3297: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2 -o conftest -I/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include -I/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include --sysroot=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk -L/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/lib/ -L/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/lib/system conftest.c  >&5
  
  configure:3301: $? = 0
  
  configure:3323: result: 
  
  configure:3345: checking whether we are cross compiling
  
  configure:3383: result: yes
  
  configure:3388: checking for suffix of object files
  
  configure:3410: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2 -c -I/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include -I/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include conftest.c >&5
  
  configure:3414: $? = 0
  
  configure:3435: result: o
  
  configure:3439: checking whether we are using the GNU C compiler
  
  configure:3458: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2 -c -I/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include -I/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include conftest.c >&5
  
  configure:3458: $? = 0
  
  configure:3467: result: yes
  
  configure:3476: checking whether /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2 accepts -g
  
  configure:3496: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2 -c -g -I/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include conftest.c >&5
  
  configure:3496: $? = 0
  
  configure:3537: result: yes
  
  configure:3554: checking for /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2 option to accept ISO C89
  
  configure:3618: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2  -c -I/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include -I/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include conftest.c >&5
  
  configure:3618: $? = 0
  
  configure:3631: result: none needed
  
  configure:3662: checking for style of include used by make
  
  configure:3690: result: GNU
  
  configure:3716: checking dependency style of /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2
  
  configure:3827: result: gcc3
  
  configure:3843: checking whether /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2 and cc understand -c and -o together
  
  configure:3874: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2 -c conftest.c -o conftest2.o >&5
  
  configure:3878: $? = 0
  
  configure:3884: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2 -c conftest.c -o conftest2.o >&5
  
  configure:3888: $? = 0
  
  configure:3899: cc -c conftest.c >&5
  
  configure:3903: $? = 0
  
  configure:3911: cc -c conftest.c -o conftest2.o >&5
  
  configure:3915: $? = 0
  
  configure:3921: cc -c conftest.c -o conftest2.o >&5
  
  configure:3925: $? = 0
  
  configure:3943: result: yes
  
  configure:3973: checking how to run the C preprocessor
  
  configure:4043: result: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-g++-4.2
  
  configure:4063: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-g++-4.2 -I/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include conftest.c
  
  conftest.c:16: error: 'Syntax' does not name a type
  
  configure:4063: $? = 1
  
  configure: failed program was:
  
  | /* confdefs.h */
  
  | #define PACKAGE_NAME "libaacplus"
  
  | #define PACKAGE_TARNAME "libaacplus"
  
  | #define PACKAGE_VERSION "2.0.2"
  
  | #define PACKAGE_STRING "libaacplus 2.0.2"
  
  | #define PACKAGE_BUGREPORT "Sergiy Guriev <piratfm@ua.fm>"
  
  | #define PACKAGE_URL ""
  
  | #define PACKAGE "libaacplus"
  
  | #define VERSION "2.0.2"
  
  | /* end confdefs.h.  */
  
  | #ifdef __STDC__
  
  | # include 
  
  | #else
  
  | # include 
  
  | #endif
  
  |            Syntax error
  
  configure:4063: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-g++-4.2 -I/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include conftest.c
  
  conftest.c:16: error: 'Syntax' does not name a type
  
  configure:4063: $? = 1
  
  configure: failed program was:
  
  | /* confdefs.h */
  
  | #define PACKAGE_NAME "libaacplus"
  
  | #define PACKAGE_TARNAME "libaacplus"
  
  | #define PACKAGE_VERSION "2.0.2"
  
  | #define PACKAGE_STRING "libaacplus 2.0.2"
  
  | #define PACKAGE_BUGREPORT "Sergiy Guriev <piratfm@ua.fm>"
  
  | #define PACKAGE_URL ""
  
  | #define PACKAGE "libaacplus"
  
  | #define VERSION "2.0.2"
  
  | /* end confdefs.h.  */
  
  | #ifdef __STDC__
  
  | # include 
  
  | #else
  
  | # include 
  
  | #endif
  
  |            Syntax error
  
  configure:4093: error: in `/Users/md313/Documents/Developer/OpenSource/ffmpef4ios-build-scripts/external-libs/libaacplus-2.0.2':
  
  configure:4096: error: C preprocessor "/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-g++-4.2" fails sanity check
  
  See `config.log' for more details.
  
  
  
  ## ---------------- ##
  
  ## Cache variables. ##
  
  ## ---------------- ##
  
  
  
  ac_cv_c_compiler_gnu=yes
  
  ac_cv_env_CC_set=set
  
  ac_cv_env_CC_value=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2
  
  ac_cv_env_CFLAGS_set=set
  
  ac_cv_env_CFLAGS_value=-I/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include
  
  ac_cv_env_CPPFLAGS_set=set
  
  ac_cv_env_CPPFLAGS_value=-I/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/include
  
  ac_cv_env_CPP_set=set
  
  ac_cv_env_CPP_value=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/arm-apple-darwin10-llvm-g++-4.2
  
  ac_cv_env_LDFLAGS_set=set
  
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  ## ----------------- ##
  
  ## Output variables. ##
  
  ## ----------------- ##
  
  
  
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  ## ----------- ##
  
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  #define VERSION "2.0.2"
  
  
  
  configure: exit 1

• A systematic approach to making Web Applications accessible

  22 février 2012, par silvia

  With the latest developments in HTML5 and the still fairly new ARIA (Accessible Rich Interface Applications) attributes introduced by the W3C WAI (Web Accessibility Initiative), browsers have now implemented many features that allow you to make your JavaScript-heavy Web applications accessible.

  Since I began working on making a complex web application accessible just over a year ago, I discovered that there was no step-by-step guide to approaching the changes necessary for creating an accessible Web application. Therefore, many people believe that it is still hard, if not impossible, to make Web applications accessible. In fact, it can be approached systematically, as this article will describe.

  This post is based on a talk that Alice Boxhall and I gave at the recent Linux.conf.au titled “Developing accessible Web apps – how hard can it be ?” (slides, video), which in turn was based on a Google Developer Day talk by Rachel Shearer (slides).

  These talks, and this article, introduce a process that you can follow to make your Web applications accessible : each step will take you closer to having an application that can be accessed using a keyboard alone, and by users of screenreaders and other accessibility technology (AT).

  The recommendations here only roughly conform to the requirements of WCAG (Web Content Accessibility Guidelines), which is the basis of legal accessibility requirements in many jurisdictions. The steps in this article may or may not be sufficient to meet a legal requirement. It is focused on the practical outcome of ensuring users with disabilities can use your Web application.

  Step-by-step Approach

  The steps to follow to make your Web apps accessible are as follows :

  1. Use native HTML tags wherever possible
  2. Make interactive elements keyboard accessible
  3. Provide extra markup for AT (accessibility technology)

  If you are a total newcomer to accessibility, I highly recommend installing a screenreader and just trying to read/navigate some Web pages. On Windows you can install the free NVDA screenreader, on Mac you can activate the pre-installed VoiceOver screenreader, on Linux you can use Orca, and if you just want a browser plugin for Chrome try installing ChromeVox.

  1. Use native HTML tags

  As you implement your Web application with interactive controls, try to use as many native HTML tags as possible.

  HTML5 provides a rich set of elements which can be used to both add functionality and provide semantic context to your page. HTML4 already included many useful interactive controls, like <a>, <button>, <input> and <select>, and semantic landmark elements like <h1>. HTML5 adds richer <input> controls, and a more sophisticated set of semantic markup elements like such as <time>, <progress>, <meter>, <nav>, <header>, <article> and <aside>. (Note : check browser support for browser support of the new tags).

  Using as much of the rich HTML5 markup as possible means that you get all of the accessibility features which have been implemented in the browser for those elements, such as keyboard support, short-cut keys and accessibility metadata, for free. For generic tags you have to implement them completely from scratch.

  What exactly do you miss out on when you use a generic tag such as <div> over a specific semantic one such as <button> ?

  1. Generic tags are not focusable. That means you cannot reach them through using the [tab] on the keyboard.
  2. You cannot activate them with the space bar or enter key or perform any other keyboard interaction that would be regarded as typical with such a control.
  3. Since the role that the control represents is not specified in code but is only exposed through your custom visual styling, screenreaders cannot express to their users what type of control it is, e.g. button or link.
  4. Neither can screenreaders add the control to the list of controls on the page that are of a certain type, e.g. to navigate to all headers of a certain level on the page.
  5. And finally you need to manually style the element in order for it to look distinctive compared to other elements on the page ; using a default control will allow the browser to provide the default style for the platform, which you can still override using CSS if you want.

  Example :

  Compare these two buttons. The first one is implemented using a <div> tag, the second one using a <button> tag. Try using a screenreader to experience the difference.

  Send	<style> .custombutton cursor : pointer ; border : 1px solid #000 ; background-color : #F6F6F6 ; display : inline-block ; padding : 2px 5px ; </style> <div class="custombutton" onclick="alert(’sent !’)"> Send </div>
  Send	<button onclick="alert(’sent !’)"> Send </button>

  2. Make interactive elements keyboard accessible

  Many sophisticated web applications have some interactive controls that just have no appropriate HTML tag equivalent. In this case, you will have had to build an interactive element with JavaScript and <div> and/or <span> tags and lots of custom styling. The good news is, it’s possible to make even these custom controls accessible, and as a side benefit you will also make your application smoother to use for power users.

  The first thing you can do to test usability of your control, or your Web app, is to unplug the mouse and try to use only the [TAB] and [ENTER] keys to interact with your application.

  

  Try the following :

  • Can you reach all interactive elements with [TAB] ?
  • Can you activate interactive elements with [ENTER] (or [SPACE]) ?
  • Are the elements in the right tab order ?
  • After interaction : is the right element in focus ?
  • Is there a keyboard shortcut that activates the element (accesskey) ?

  No ? Let’s fix it.

  2.1. Reaching interactive elements

  If you have an element on your page that cannot be reached with [TAB], put a @tabindex attribute on it.

  Example :

  Here we have a <span> tag that works as a link (don’t do this – it’s just a simple example). The first one cannot be reached using [TAB] but the second one has a tabindex and is thus part of the tab order of the HTML page.

  (Note : since we experiment lots with the tabindex in this article, to avoid confusion, click on some text in this paragraph and then hit the [TAB] key to see where it goes next. The click will set your keyboard focus in the DOM.)

  Click	<style> .customlink text-decoration : underline ; cursor : pointer ; </style> <span class="customlink" onclick="alert(’activated !’)"> Click </span>
  Click	<style> .customlink text-decoration : underline ; cursor : pointer ; </style> <span class="customlink" onclick="alert(’activated !’)" tabindex="0"> Click </span>

  You set @tabindex=0 to add an element into the native tab order of the page, which is the DOM order.

  2.2. Activating interactive elements

  Next, you typically want to be able to use the [ENTER] and [SPACE] keys to activate your custom control. To do so, you will need to implement an onkeydown event handler. Note that the keyCode for [ENTER] is 13 and for [SPACE] is 32.

  Example :

  Let’s add this functionality to the <span> tag from before. Try tabbing to it and hit the [ENTER] or [SPACE] key.

  Click	<span class="customlink" onclick="alert(’activated !’)" tabindex="0"> Click </span>
  &lt;script&gt;<br /> function handlekey(event) {<br /> var target = event.target || event.srcElement;<br /> if (event.keyCode == 13 || event.keyCode == 32) { target.onclick(); }<br /> }<br /> &lt;/script&gt; Click	<span class="customlink" onclick="alert(’activated !’)" tabindex="0" onkeydown="handlekey(event) ;"> Click </span> <script> function handlekey(event) var target = event.target || event.srcElement ; if (event.keyCode == 13 || event.keyCode == 32) target.onclick() ; </script>

  Note that there are some controls that might need support for keys other than [tab] or [enter] to be able to use them from the keyboard alone, for example a custom list box, menu or slider should respond to arrow keys.

  2.3. Elements in the right tab order

  Have you tried tabbing to all the elements on your page that you care about ? If so, check if the order of tab stops seems right. The default order is given by the order in which interactive elements appear in the DOM. For example, if your page’s code has a right column that is coded before the main article, then the links in the right column will receive tab focus first before the links in the main article.

  You could change this by re-ordering your DOM, but oftentimes this is not possible. So, instead give the elements that should be the first ones to receive tab focus a positive @tabindex. The tab access will start at the smallest non-zero @tabindex value. If multiple elements share the same @tabindex value, these controls receive tab focus in DOM order. After that, interactive elements and those with @tabindex=0 will receive tab focus in DOM order.

  Example :

  The one thing that always annoys me the most is if the tab order in forms that I am supposed to fill in is illogical. Here is an example where the first and last name are separated by the address because they are in a table. We could fix it by moving to a <div> based layout, but let’s use @tabindex to demonstrate the change.

  Firstname : Address : Lastname : City :	<table class="customtabs"> <tr> <td>Firstname : <input type="text" id="firstname"> </td> <td>Address : <input type="text" id="address"> </td> </tr> <tr> <td>Lastname : <input type="text" id="lastname"> </td> <td>City : <input type="text" id="city"> </td> </tr> </table>
  Click here to test this form, then [TAB] : Firstname : Address : Lastname : City :	<table class="customtabs"> <tr> <td>Firstname : <input type="text" id="firstname" tabindex="10"> </td> <td>Address : <input type="text" id="address" tabindex="30"> </td> </tr> <tr> <td>Lastname : <input type="text" id="lastname" tabindex="20"> </td> <td>City : <input type="text" id="city" tabindex="40"> </td> </tr> </table>

  Be very careful with using non-zero tabindex values. Since they change the tab order on the page, you may get side effects that you might not have intended, such as having to give other elements on the page a non-zero tabindex value to avoid skipping too many other elements as I would need to do here.

  2.4. Focus on the right element

  Some of the controls that you create may be rather complex and open elements on the page that were previously hidden. This is particularly the case for drop-downs, pop-ups, and menus in general. Oftentimes the hidden element is not defined in the DOM right after the interactive control, such that a [TAB] will not put your keyboard focus on the next element that you are interacting with.

  The solution is to manage your keyboard focus from JavaScript using the .focus() method.

  Example :

  Here is a menu that is declared ahead of the menu button. If you tab onto the button and hit enter, the menu is revealed. But your tab focus is still on the menu button, so your next [TAB] will take you somewhere else. We fix it by setting the focus on the first menu item after opening the menu.

  Menu item1 Menu item2 Menu &lt;script&gt;<br /> function displayMenu(value) {<br /> document.getElementById(&quot;custommenu&quot;).style.display=value;<br /> }<br /> &lt;/script&gt;	<div id="custommenu" style="display:none ;"> <button id="item1" onclick="displayMenu(’none’) ;">Menu item1</button> <button id="item2" onclick="displayMenu(’none’) ;">Menu item2</button> </div> <button onclick="displayMenu(’block’) ;">Menu</button> <script> function displayMenu(value) document.getElementById("custommenu").style.display=value ; </script>
  Menu item1 Menu item2 Menu &lt;script&gt;<br /> function displayMenu2(value) {<br /> document.getElementById(&quot;custommenu2&quot;).style.display=value;<br /> document.getElementById(&quot;item1&quot;).focus();<br /> }<br /> &lt;/script&gt;	<div id="custommenu" style="display:none ;"> <button id="item1" onclick="displayMenu(’none’) ;">Menu item1</button> <button id="item2" onclick="displayMenu(’none’) ;">Menu item2</button> </div> <button onclick="displayMenu(’block’) ;">Menu</button> <script> function displayMenu(value) document.getElementById("custommenu").style.display=value ; document.getElementById("item1").focus() ; </script>

  You will notice that there are still some things you can improve on here. For example, after you close the menu again with one of the menu items, the focus does not move back onto the menu button.

  Also, after opening the menu, you may prefer not to move the focus onto the first menu item but rather just onto the menu <div>. You can do so by giving that div a @tabindex and then calling .focus() on it. If you do not want to make the div part of the normal tabbing order, just give it a @tabindex=-1 value. This will allow your div to receive focus from script, but be exempt from accidental tabbing onto (though usually you just want to use @tabindex=0).

  Bonus : If you want to help keyboard users even more, you can also put outlines on the element that is currently in focus using CSS”s outline property. If you want to avoid the outlines for mouse users, you can dynamically add a class that removes the outline in mouseover events but leaves it for :focus.

  2.5. Provide sensible keyboard shortcuts

  At this stage your application is actually keyboard accessible. Congratulations !

  However, it’s still not very efficient : like power-users, screenreader users love keyboard shortcuts : can you imagine if you were forced to tab through an entire page, or navigate back to a menu tree at the top of the page, to reach each control you were interested in ? And, obviously, anything which makes navigating the app via the keyboard more efficient for screenreader users will benefit all power users as well, like the ubiquitous keyboard shortcuts for cut, copy and paste.

  HTML4 introduced so-called accesskeys for this. In HTML5 @accesskey is now allowed on all elements.

  The @accesskey attribute takes the value of a keyboard key (e.g. @accesskey="x") and is activated through platform- and browser-specific activation keys. For example, on the Mac it’s generally the [Ctrl] key, in IE it’ the [Alt] key, in Firefox on Windows [Shift]-[Alt], and in Opera on Windows [Shift]-[ESC]. You press the activation key and the accesskey together which either activates or focuses the element with the @accesskey attribute.

  Example :

  Send &lt;script&gt;<br /> var button = document.getElementById('accessbutton');<br /> if (button.accessKeyLabel) {<br />  button.innerHTML += ' (' + button.accessKeyLabel + ')';<br /> }<br /> &lt;/script&gt;

  <button id="accessbutton" onclick="alert(’sent !’)" accesskey="e"> Send </button> <script> var button = document.getElementById(’accessbutton’) ; if (button.accessKeyLabel) button.innerHTML += ’ (’ + button.accessKeyLabel + ’)’ ; </script>

  Now, the idea behind this is clever, but the execution is pretty poor. Firstly, the different activation keys between different platforms and browsers make it really hard for people to get used to the accesskeys. Secondly, the key combinations can conflict with browser and screenreader shortcut keys, the first of which will render browser shortcuts unusable and the second will effectively remove the accesskeys.

  In the end it is up to the Web application developer whether to use the accesskey attribute or whether to implement explicit shortcut keys for the application through key event handlers on the window object. In either case, make sure to provide a help list for your shortcut keys.

  Also note that a page with a really good hierarchical heading layout and use of ARIA landmarks can help to eliminate the need for accesskeys to jump around the page, since there are typically default navigations available in screen readers to jump directly to headings, hyperlinks, and ARIA landmarks.

  3. Provide markup for AT

  Having made the application keyboard accessible also has advantages for screenreaders, since they can now reach the controls individually and activate them. So, next we will use a screenreader and close our eyes to find out where we only provide visual cues to understand the necessary interaction.

  Here are some of the issues to consider :

  • Role may need to get identified
  • States may need to be kept track of
  • Properties may need to be made explicit
  • Labels may need to be provided for elements

  This is where the W3C’s ARIA (Accessible Rich Internet Applications) standard comes in. ARIA attributes provide semantic information to screen readers and other AT that is otherwise conveyed only visually.

  Note that using ARIA does not automatically implement the standard widget behavior – you’ll still need to add focus management, keyboard navigation, and change aria attribute values in script.

  3.1. ARIA roles

  After implementing a custom interactive widget, you need to add a @role attribute to indicate what type of controls it is, e.g. that it is playing the role of a standard tag such as a button.

  Example :

  This menu button is implemented as a <div>, but with a role of “button” it is announced as a button by a screenreader.

  Menu	<div tabindex="0" role="button">Menu</div>

  ARIA roles also describe composite controls that do not have a native HTML equivalent.

  Example :

  This menu with menu items is implemented as a set of <div> tags, but with a role of “menu” and “menuitem” items.

  Cut Copy Paste

  <div role="menu"> <div tabindex="0" role="menuitem">Cut</div> <div tabindex="0" role="menuitem">Copy</div> <div tabindex="0" role="menuitem">Paste</div> </div>

  3.2. ARIA states

  Some interactive controls represent different states, e.g. a checkbox can be checked or unchecked, or a menu can be expanded or collapsed.

  Example :

  The following menu has states on the menu items, which are here not just used to give an aural indication through the screenreader, but also a visual one through CSS.

  Left Center Right

  <style> .custombutton[aria-checked=true]:before content : "\2713 " ; </style> <div role="menu"> <div tabindex="0" role="menuitem" aria-checked="true">Left</div> <div tabindex="0" role="menuitem" aria-checked="false">Center</div> <div tabindex="0" role="menuitem" aria-checked="false">Right</div> </div>

  3.3. ARIA properties

  Some of the functionality of interactive controls cannot be captured by the role attribute alone. We have ARIA properties to add features that the screenreader needs to announce, such as aria-label, aria-haspopup, aria-activedescendant, or aria-live.

  Example :

  The following drop-down menu uses aria-haspopup to tell the screenreader that there is a popup hidden behind the menu button together with an ARIA state of aria-expanded to track whether it’s open or closed.

  Justify Left Center Right &lt;script&gt;<br /> var button = document.getElementById(&quot;button&quot;);<br /> var menu = document.getElementById(&quot;menu&quot;);<br /> var items = document.getElementsByClassName(&quot;menuitem&quot;);<br /> var focused = 0;<br /> function showMenu(evt) {<br />    evt.stopPropagation();<br />    menu.style.visibility = 'visible';<br />    button.setAttribute('aria-expanded','true');<br />    focused = getSelected();<br />    items[focused].focus();<br />  }<br />  function hideMenu(evt) {<br />    evt.stopPropagation();<br />    menu.style.visibility = 'hidden';<br />    button.setAttribute('aria-expanded','false');<br />    button.focus();<br />  }<br />  function getSelected() {<br />    for (var i=0; i &lt; items.length; i++) {<br />      if (items[i].getAttribute('aria-checked') == 'true') {<br />        return i;<br />      }<br />    }<br />  }<br />  function setSelected(elem) {<br />    var curSelected = getSelected();<br />    items[curSelected].setAttribute('aria-checked', 'false');<br />    elem.setAttribute('aria-checked', 'true');<br />  }<br />  function selectItem(evt) {<br />    setSelected(evt.target);<br />    hideMenu(evt);<br />  }<br /> function getPrevItem(index) {<br />    var prev = index - 1;<br />    if (prev &lt; 0) {<br />      prev = items.length - 1;<br />    }<br />    return prev;<br />  }<br />  function getNextItem(index) {<br />    var next = index + 1;<br />    if (next == items.length) {<br />      next = 0;<br />    }<br />    return next;<br />  }<br /> function handleButtonKeys(evt) {<br />    evt.stopPropagation();<br />    var key = evt.keyCode;<br />    switch(key) {<br />      case (13): /* ENTER */<br />      case (32): /* SPACE */<br />        showMenu(evt);<br />      default:<br />    }<br />  }<br />  function handleMenuKeys(evt) {<br />    evt.stopPropagation();<br />    var key = evt.keyCode;<br />    switch(key) {<br />      case (38): /* UP */<br />        focused = getPrevItem(focused);<br />        items[focused].focus();<br />        break;<br />      case (40): /* DOWN */<br />        focused = getNextItem(focused);<br />        items[focused].focus();<br />        break;<br />      case (13): /* ENTER */<br />      case (32): /* SPACE */<br />        setSelected(evt.target);<br />          hideMenu(evt);<br />          break;<br />      case (27): /* ESC */<br />        hideMenu(evt);<br />         break;<br />      default:<br />    }<br />  }<br />  button.addEventListener('click', showMenu, false);<br />  button.addEventListener('keydown', handleButtonKeys, false);<br />  for (var i = 0;  i &lt; items.length; i++) {<br />    items[i].addEventListener('click', selectItem, false);<br />    items[i].addEventListener('keydown', handleMenuKeys, false);<br />  }<br /> &lt;/script&gt;

  <div class="custombutton" id="button" tabindex="0" role="button" aria-expanded="false" aria-haspopup="true"> <span>Justify</span> </div> <div role="menu" class="menu" id="menu" style="display : none ;"> <div tabindex="0" role="menuitem" class="menuitem" aria-checked="true"> Left </div> <div tabindex="0" role="menuitem" class="menuitem" aria-checked="false"> Center </div> <div tabindex="0" role="menuitem" class="menuitem" aria-checked="false"> Right </div> </div> [CSS and JavaScript for example omitted]

  3.4. Labelling

  The main issue that people know about accessibility seems to be that they have to put alt text onto images. This is only one means to provide labels to screenreaders for page content. Labels are short informative pieces of text that provide a name to a control.

  There are actually several ways of providing labels for controls :

  • on img elements use @alt
  • on input elements use the label element
  • use @aria-labelledby if there is another element that contains the label
  • use @title if you also want a label to be used as a tooltip
  • otherwise use @aria-label

  I’ll provide examples for the first two use cases - the other use cases are simple to deduce.

  Example :

  The following two images show the rough concept for providing alt text for images : images that provide information should be transcribed, images that are just decorative should receive an empty @alt attribute.

  Image by Noah Sussman

  <img src="texture.jpg" alt=""> <img src="lolcat.jpg" alt="shocked lolcat titled ’HTML cannot do that !"> <img src="texture.jpg" alt="">

  When marking up decorative images with an empty @alt attribute, the image is actually completely removed from the accessibility tree and does not confuse the blind user. This is a desired effect, so do remember to mark up all your images with @alt attributes, even those that don’t contain anything of interest to AT.

  Example :

  In the example form above in Section 2.3, when tabbing directly on the input elements, the screen reader will only say "edit text" without announcing what meaning that text has. That’s not very useful. So let’s introduce a label element for the input elements. We’ll also add checkboxes with a label.

  Doctor title : Firstname : Lastname : Address : City : Remember me :

  <label>Doctor title :</label> <input type="checkbox" id="doctor"/> <label>Firstname :</label> <input type="text" id="firstname2"/> <label for="lastname2">Lastname :</label> <input type="text" id="lastname2"/> <label>Address : <input type="text" id="address2"> </label> <label for="city2">City : <input type="text" id="city2"> </label> <label for="remember">Remember me :</label> <input type="checkbox" id="remember">

  In this example we use several different approaches to show what a different it makes to use the <label> element to mark up input boxes.

  The first two fields just have a <label> element next to a <input> element. When using a screenreader you will not notice a difference between this and not using the <label> element because there is no connection between the <label> and the <input> element.

  In the third field we use the @for attribute to create that link. Now the input field isn’t just announced as "edit text", but rather as "Lastname edit text", which is much more useful. Also, the screenreader can now skip the labels and get straight on the input element.

  In the fourth and fifth field we actually encapsulate the <input> element inside the <label> element, thus avoiding the need for a @for attribute, though it doesn’t hurt to explicity add it.

  Finally we look at the checkbox. By including a referenced <label> element with the checkbox, we change the screenreaders announcement from just "checkbox not checked" to "Remember me checkbox not checked". Also notice that the click target now includes the label, making the checkbox not only more usable to screenreaders, but also for mouse users.

  4. Conclusions

  This article introduced a process that you can follow to make your Web applications accessible. As you do that, you will noticed that there are other things that you may need to do in order to give the best experience to a power user on a keyboard, a blind user using a screenreader, or a vision-impaired user using a screen magnifier. But once you’ve made a start, you will notice that it’s not all black magic and a lot can be achieved with just a little markup.

  You will find more markup in the WAI ARIA specification and many more resources at Mozilla’s ARIA portal. Now go and change the world !

  Many thanks to Alice Boxhall and Dominic Mazzoni for their proof-reading and suggested changes that really helped improve the article !

• Forcing ffmpeg to capture unreliable ALSA audio stream

  6 février 2015, par Peter Becich

  I am attempting to transfer some old Video 8 tapes to my computer, though an EasyCap USB stick and the motherboard’s sound line-in, on Ubuntu. I believe the arguments are correctly laid out below to capture from two independent streams, and encode them both into the output MP4 file.

  ffmpeg’s detection of the ALSA stream is seemingly goofed up by the inconsistencies of the tape. In the failure case, only short blips of the tapes audio exist in the output MP4. The audio bitrate of the output file is less than 10 kbps, averaged out across the whole file. The output video seems to be fine, even though the low frames-per-second in the failure case log below.

  The audio and video streams can be captured fine for short amounts of time before a source error occurs ; this provides the success case log. The failure case log was created by intentionally making an error in the source streams — turning on the camera makes a brief noisy signal.

  Is there a setting that needs to be forced to keep ffmpeg recording the audio stream, even when the tape is blank or noisy ?

  Could it be that the libfdk_aac audio encoder is tripped up by the low quality source ?

  The relevant line ; rawvideo stream is piped to this in script at bottom :

  ffmpeg -pixel_format uyvy422 -s:v 720x480 -framerate 29.97 -f rawvideo \
  
  -i $PIPE  -f alsa -i hw:0,0 -vf scale=w=720:h=540 -vcodec libx264 \
  
  -preset ultrafast -shortest -c:a libfdk_aac -b:a 128k -af pan=1:c0=c0  \
  
  -ar 96000 $OUTFILE

  The ar argument was one attempt to force recording.

  ffmpeg log file for (short-lived) success ; high frames-per-second captured :

  ffmpeg version 2.5.3 Copyright (c) 2000-2015 the FFmpeg developers
  
    built on Jan 11 2015 17:53:45 with gcc 4.8 (Ubuntu 4.8.2-19ubuntu1)
  
    configuration: --extra-libs=-ldl --prefix=/opt/ffmpeg --enable-avresample --disable-debug --enable-nonfree --enable-gpl --enable-version3 --enable-libpulse --enable-libopencore-amrnb --enable-libopencore-amrwb --disable-decoder=amrnb --disable-decoder=amrwb --enable-libx264 --enable-libx265 --enable-libfdk-aac --enable-libvorbis --enable-libmp3lame --enable-libopus --enable-libvpx --enable-libspeex --enable-libass --enable-avisynth --enable-libsoxr --enable-libxvid --enable-libvo-aacenc --enable-libvidstab
  
    libavutil      54. 15.100 / 54. 15.100
  
    libavcodec     56. 13.100 / 56. 13.100
  
    libavformat    56. 15.102 / 56. 15.102
  
    libavdevice    56.  3.100 / 56.  3.100
  
    libavfilter     5.  2.103 /  5.  2.103
  
    libavresample   2.  1.  0 /  2.  1.  0
  
    libswscale      3.  1.101 /  3.  1.101
  
    libswresample   1.  1.100 /  1.  1.100
  
    libpostproc    53.  3.100 / 53.  3.100
  
  Input #0, rawvideo, from '/tmp/somagic-pipe':
  
    Duration: N/A, start: 0.000000, bitrate: 165722 kb/s
  
      Stream #0:0: Video: rawvideo (UYVY / 0x59565955), uyvy422, 720x480, 165722 kb/s, 29.97 tbr, 29.97 tbn, 29.97 tbc
  
  Home directory not accessible: Permission denied
  
  Guessed Channel Layout for  Input Stream #1.0 : stereo
  
  Input #1, alsa, from 'hw:0,0':
  
    Duration: N/A, start: 1423202268.577088, bitrate: 1536 kb/s
  
      Stream #1:0: Audio: pcm_s16le, 48000 Hz, 2 channels, s16, 1536 kb/s
  
  No pixel format specified, yuv422p for H.264 encoding chosen.
  
  Use -pix_fmt yuv420p for compatibility with outdated media players.
  
  [Parsed_pan_0 @ 0x3335d60] This syntax is deprecated. Use '|' to separate the list items.
  
  Single channel layout '1' is interpreted as a number of channels, switch to the syntax '1c' otherwise it will be interpreted as a channel layout number in a later version
  
  [Parsed_pan_0 @ 0x3335d60] Pure channel mapping detected: 0
  
  [libx264 @ 0x3364bc0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64
  
  [libx264 @ 0x3364bc0] profile High 4:2:2, level 3.1, 4:2:2 8-bit
  
  [libx264 @ 0x3364bc0] 264 - core 142 r2389 956c8d8 - H.264/MPEG-4 AVC codec - Copyleft 2003-2014 - http://www.videolan.org/x264.html - options: cabac=0 ref=1 deblock=0:0:0 analyse=0:0 me=dia subme=0 psy=1 psy_rd=1.00:0.00 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=0 threads=3 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=0 keyint=250 keyint_min=25 scenecut=0 intra_refresh=0 rc=crf mbtree=0 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=0
  
  Output #0, mp4, to '/home/peterbecich/easycap/Videos/fpv_video_02_05_2015_21_57_48.mp4':
  
    Metadata:
  
      encoder         : Lavf56.15.102
  
      Stream #0:0: Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv422p, 720x540, q=-1--1, 29.97 fps, 11988 tbn, 29.97 tbc
  
      Metadata:
  
        encoder         : Lavc56.13.100 libx264
  
      Stream #0:1: Audio: aac (libfdk_aac) ([64][0][0][0] / 0x0040), 96000 Hz, mono, s16, 128 kb/s
  
      Metadata:
  
        encoder         : Lavc56.13.100 libfdk_aac
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (rawvideo (native) -> h264 (libx264))
  
    Stream #1:0 -> #0:1 (pcm_s16le (native) -> aac (libfdk_aac))
  
  Press [q] to stop, [?] for help
  
  frame=   13 fps=0.0 q=26.0 size=     187kB time=00:00:00.30 bitrate=5102.7kbits/s    
  
  frame=   29 fps= 29 q=26.0 size=     469kB time=00:00:00.83 bitrate=4607.6kbits/s    
  
  frame=   44 fps= 29 q=26.0 size=     755kB time=00:00:01.33 bitrate=4635.2kbits/s    
  
  frame=   59 fps= 29 q=26.0 size=    1024kB time=00:00:01.83 bitrate=4572.1kbits/s    
  
  frame=   74 fps= 29 q=26.0 size=    1279kB time=00:00:02.33 bitrate=4486.5kbits/s    
  
  frame=   89 fps= 29 q=26.0 size=    1516kB time=00:00:02.83 bitrate=4378.0kbits/s    
  
  frame=  104 fps= 29 q=26.0 size=    1752kB time=00:00:03.33 bitrate=4301.0kbits/s    
  
  frame=  119 fps= 29 q=26.0 size=    1991kB time=00:00:03.83 bitrate=4251.1kbits/s    
  
  frame=  135 fps= 30 q=26.0 size=    2245kB time=00:00:04.37 bitrate=4207.5kbits/s    
  
  frame=  150 fps= 30 q=26.0 size=    2524kB time=00:00:04.87 bitrate=4245.0kbits/s    
  
  frame=  165 fps= 30 q=26.0 size=    2808kB time=00:00:05.37 bitrate=4282.0kbits/s    
  
  frame=  180 fps= 30 q=26.0 size=    3091kB time=00:00:05.87 bitrate=4311.5kbits/s    
  
  [rawvideo @ 0x3350640] Invalid buffer size, packet size 65536 < expected frame_size 691200
  
  Error while decoding stream #0:0: Invalid argument
  
  frame=  183 fps= 29 q=-1.0 Lsize=    3247kB time=00:00:06.11 bitrate=4351.5kbits/s    
  
  video:3142kB audio:96kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.254788%
  
  [libx264 @ 0x3364bc0] frame I:1     Avg QP:20.00  size:  2289
  
  [libx264 @ 0x3364bc0] frame P:182   Avg QP:25.99  size: 17664
  
  [libx264 @ 0x3364bc0] mb I  I16..4: 100.0%  0.0%  0.0%
  
  [libx264 @ 0x3364bc0] mb P  I16..4: 78.5%  0.0%  0.0%  P16..4: 20.2%  0.0%  0.0%  0.0%  0.0%    skip: 1.4%
  
  [libx264 @ 0x3364bc0] coded y,uvDC,uvAC intra: 84.1% 71.5% 18.9% inter: 51.9% 63.5% 0.4%
  
  [libx264 @ 0x3364bc0] i16 v,h,dc,p: 15%  8% 69%  8%
  
  [libx264 @ 0x3364bc0] i8c dc,h,v,p: 50% 19% 24%  7%
  
  [libx264 @ 0x3364bc0] kb/s:4215.02

  ffmpeg log for failure ; low FPS captured :

  ffmpeg version 2.5.3 Copyright (c) 2000-2015 the FFmpeg developers
  
    built on Jan 11 2015 17:53:45 with gcc 4.8 (Ubuntu 4.8.2-19ubuntu1)
  
    configuration: --extra-libs=-ldl --prefix=/opt/ffmpeg --enable-avresample --disable-debug --enable-nonfree --enable-gpl --enable-version3 --enable-libpulse --enable-libopencore-amrnb --enable-libopencore-amrwb --disable-decoder=amrnb --disable-decoder=amrwb --enable-libx264 --enable-libx265 --enable-libfdk-aac --enable-libvorbis --enable-libmp3lame --enable-libopus --enable-libvpx --enable-libspeex --enable-libass --enable-avisynth --enable-libsoxr --enable-libxvid --enable-libvo-aacenc --enable-libvidstab
  
    libavutil      54. 15.100 / 54. 15.100
  
    libavcodec     56. 13.100 / 56. 13.100
  
    libavformat    56. 15.102 / 56. 15.102
  
    libavdevice    56.  3.100 / 56.  3.100
  
    libavfilter     5.  2.103 /  5.  2.103
  
    libavresample   2.  1.  0 /  2.  1.  0
  
    libswscale      3.  1.101 /  3.  1.101
  
    libswresample   1.  1.100 /  1.  1.100
  
    libpostproc    53.  3.100 / 53.  3.100
  
  Input #0, rawvideo, from '/tmp/somagic-pipe':
  
    Duration: N/A, start: 0.000000, bitrate: 165722 kb/s
  
      Stream #0:0: Video: rawvideo (UYVY / 0x59565955), uyvy422, 720x480, 165722 kb/s, 29.97 tbr, 29.97 tbn, 29.97 tbc
  
  Home directory not accessible: Permission denied
  
  Guessed Channel Layout for  Input Stream #1.0 : stereo
  
  Input #1, alsa, from 'hw:0,0':
  
    Duration: N/A, start: 1423201999.226455, bitrate: 1536 kb/s
  
      Stream #1:0: Audio: pcm_s16le, 48000 Hz, 2 channels, s16, 1536 kb/s
  
  No pixel format specified, yuv422p for H.264 encoding chosen.
  
  Use -pix_fmt yuv420p for compatibility with outdated media players.
  
  [Parsed_pan_0 @ 0x21cad60] This syntax is deprecated. Use '|' to separate the list items.
  
  Single channel layout '1' is interpreted as a number of channels, switch to the syntax '1c' otherwise it will be interpreted as a channel layout number in a later version
  
  [Parsed_pan_0 @ 0x21cad60] Pure channel mapping detected: 0
  
  [libx264 @ 0x21f9bc0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64
  
  [libx264 @ 0x21f9bc0] profile High 4:2:2, level 3.1, 4:2:2 8-bit
  
  [libx264 @ 0x21f9bc0] 264 - core 142 r2389 956c8d8 - H.264/MPEG-4 AVC codec - Copyleft 2003-2014 - http://www.videolan.org/x264.html - options: cabac=0 ref=1 deblock=0:0:0 analyse=0:0 me=dia subme=0 psy=1 psy_rd=1.00:0.00 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=0 threads=3 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=0 keyint=250 keyint_min=25 scenecut=0 intra_refresh=0 rc=crf mbtree=0 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=0
  
  Output #0, mp4, to '/home/peterbecich/easycap/Videos/fpv_video_02_05_2015_21_53_18.mp4':
  
    Metadata:
  
      encoder         : Lavf56.15.102
  
      Stream #0:0: Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv422p, 720x540, q=-1--1, 29.97 fps, 11988 tbn, 29.97 tbc
  
      Metadata:
  
        encoder         : Lavc56.13.100 libx264
  
      Stream #0:1: Audio: aac (libfdk_aac) ([64][0][0][0] / 0x0040), 96000 Hz, mono, s16, 128 kb/s
  
      Metadata:
  
        encoder         : Lavc56.13.100 libfdk_aac
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (rawvideo (native) -> h264 (libx264))
  
    Stream #1:0 -> #0:1 (pcm_s16le (native) -> aac (libfdk_aac))
  
  Press [q] to stop, [?] for help
  
  frame=    1 fps=0.0 q=0.0 size=       0kB time=00:00:00.00 bitrate=N/A    
  
  frame=    1 fps=1.0 q=0.0 size=       0kB time=00:00:00.00 bitrate=N/A    
  
  frame=    1 fps=0.7 q=0.0 size=       0kB time=00:00:00.00 bitrate=N/A    
  
  frame=    1 fps=0.5 q=0.0 size=       0kB time=00:00:00.00 bitrate=N/A    
  
  frame=    1 fps=0.4 q=0.0 size=       0kB time=00:00:00.00 bitrate=N/A    
  
  frame=    1 fps=0.3 q=0.0 size=       0kB time=00:00:00.00 bitrate=N/A    
  
  frame=    1 fps=0.3 q=0.0 size=       0kB time=00:00:00.00 bitrate=N/A    
  
  frame=    1 fps=0.2 q=0.0 size=       0kB time=00:00:00.00 bitrate=N/A    
  
  frame=    1 fps=0.2 q=0.0 size=       0kB time=00:00:00.00 bitrate=N/A    
  
  frame=    1 fps=0.2 q=0.0 size=       0kB time=00:00:00.00 bitrate=N/A    
  
  frame=    1 fps=0.2 q=0.0 size=       0kB time=00:00:00.00 bitrate=N/A    
  
  [alsa @ 0x21e5ac0] ALSA buffer xrun.
  
  frame=    8 fps=1.3 q=19.0 size=      12kB time=00:00:06.03 bitrate=  15.9kbits/s    
  
  frame=   23 fps=3.5 q=18.0 size=      12kB time=00:00:06.03 bitrate=  16.4kbits/s    
  
  frame=   38 fps=5.4 q=18.0 size=      12kB time=00:00:06.03 bitrate=  16.7kbits/s    
  
  frame=   53 fps=7.0 q=18.0 size=      12kB time=00:00:06.03 bitrate=  16.9kbits/s    
  
  frame=   68 fps=8.4 q=26.0 size=     146kB time=00:00:06.03 bitrate= 198.8kbits/s    
  
  frame=   83 fps=9.7 q=26.0 size=     375kB time=00:00:06.03 bitrate= 510.0kbits/s    
  
  frame=   98 fps= 11 q=26.0 size=     608kB time=00:00:06.03 bitrate= 826.5kbits/s    
  
  frame=  114 fps= 12 q=26.0 size=     875kB time=00:00:06.03 bitrate=1189.1kbits/s    
  
  frame=  128 fps= 13 q=26.0 size=    1091kB time=00:00:06.03 bitrate=1481.6kbits/s    
  
  frame=  144 fps= 14 q=26.0 size=    1339kB time=00:00:06.03 bitrate=1819.2kbits/s    
  
  frame=  159 fps= 14 q=26.0 size=    1571kB time=00:00:06.03 bitrate=2134.6kbits/s    
  
  frame=  174 fps= 15 q=26.0 size=    1796kB time=00:00:06.03 bitrate=2440.1kbits/s    
  
  [alsa @ 0x21e5ac0] ALSA buffer xrun.
  
  frame=  189 fps= 16 q=26.0 size=    2015kB time=00:00:12.04 bitrate=1370.4kbits/s    
  
  frame=  204 fps= 16 q=26.0 size=    2238kB time=00:00:12.04 bitrate=1522.3kbits/s    
  
  frame=  219 fps= 17 q=26.0 size=    2490kB time=00:00:12.04 bitrate=1694.2kbits/s    
  
  frame=  235 fps= 17 q=26.0 size=    2728kB time=00:00:12.04 bitrate=1855.8kbits/s    
  
  frame=  250 fps= 18 q=26.0 size=    2973kB time=00:00:12.04 bitrate=2022.4kbits/s    
  
  [rawvideo @ 0x21e5640] Invalid buffer size, packet size 65536 < expected frame_size 691200
  
  Error while decoding stream #0:0: Invalid argument
  
  frame=  261 fps= 18 q=-1.0 Lsize=    3269kB time=00:00:12.06 bitrate=2220.1kbits/s    
  
  video:3263kB audio:4kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.081101%
  
  [libx264 @ 0x21f9bc0] frame I:2     Avg QP:21.50  size: 21342
  
  [libx264 @ 0x21f9bc0] frame P:259   Avg QP:24.22  size: 12734
  
  [libx264 @ 0x21f9bc0] mb I  I16..4: 100.0%  0.0%  0.0%
  
  [libx264 @ 0x21f9bc0] mb P  I16..4: 62.8%  0.0%  0.0%  P16..4: 14.2%  0.0%  0.0%  0.0%  0.0%    skip:22.9%
  
  [libx264 @ 0x21f9bc0] coded y,uvDC,uvAC intra: 77.7% 61.2% 14.1% inter: 19.7% 24.8% 1.6%
  
  [libx264 @ 0x21f9bc0] i16 v,h,dc,p: 17% 10% 65%  8%
  
  [libx264 @ 0x21f9bc0] i8c dc,h,v,p: 52% 18% 24%  6%
  
  [libx264 @ 0x21f9bc0] kb/s:3068.90

  The whole script :

  #!/bin/sh
  
  
  
  PIPE=/tmp/somagic-pipe
  
  OUTFILEDIR=~/easycap/Videos/
  
  LOGDIR=~/.somagic-log/
  
  NOW=`date +"%m_%d_%Y_%H_%M_%S"`
  
  
  
  OUTFILE=${OUTFILEDIR}fpv_video_${NOW}.mp4
  
  
  
  mkdir $LOGDIR
  
  
  
  FFMPEG_LOG=${LOGDIR}ffmpeg.log
  
  SOMAGIC_LOG=${LOGDIR}somagic.log
  
  MPLAYER_LOG=${LOGDIR}mplayer.log
  
  
  
  rm $PIPE >/dev/null 2>&1
  
  rm $OUTFILE >/dev/null 2>&1
  
  
  
  rm $FFMPEG_LOG
  
  rm $SOMAGIC_LOG
  
  rm $MPLAYER_LOG
  
  
  
  mkfifo $PIPE >/dev/null 2>&1
  
  
  
  ffmpeg -pixel_format uyvy422 -s:v 720x480 -framerate 29.97 -f rawvideo \
  
  -i $PIPE  -f alsa -i hw:0,0 -vf scale=w=720:h=540 -vcodec libx264 \
  
  -preset ultrafast -shortest -c:a libfdk_aac -b:a 128k -af pan=1:c0=c0  \
  
  -ar 96000 $OUTFILE > $FFMPEG_LOG 2>&1 &
  
  
  
  somagic-capture --ntsc -c --luminance=2 --lum-aperture=3 2> $SOMAGIC_LOG \
  
  | tee $PIPE | \
  
  mplayer -vf yadif,screenshot -demuxer rawvideo -rawvideo \
  
  "ntsc:format=uyvy:fps=30000/1001" -aspect 4:3 - 2> $MPLAYER_LOG
  
  
  
  
  
  rm $PIPE >/dev/null 2>&1 

  Modified from here : https://gist.github.com/Brick85/0b327ac2d3d45e23ed33