How can I get FFmpeg to locate installed libraries

Question

I've been going at this, literally for days. I'm trying to build FFmpeg with libmp3lame for use in an Android application. The build script sets a --sysroot flag that points to the Android NDK directory necessary to build these libraries in a way that Android can use them.

The problem comes when I add the flag to --enable-libmp3lame; I get ERROR: libmp3lame >= 3.98.3 not found during the build start up. I know that LAME, and it's libraries are installed, because I can just run ./configure --enable-libmp3lame manually and the configuration launches without a hitch, and shows that libmp3lame is enabled for this build. However, building like this will simply not work for what I need it for, since I need the Android NDK to do some work.

I've tracked the problem down to the fact that this build script is declaring the sysroot, and through some research, I've tried adding -Luser/include, -L/user/includeto the extra cflags, and ldflags (which I've read is the default search location for gcc). I've tried several other things as well, but I'm confident that someone out here can help with this specific problem. This entire build script is as follows:

Extra info:

• Build OS: Ubuntu 11.10
• FFmpeg Ver: Latest from git
• LAME Ver: 3.9.x
• Android NDK: r7

build.sh

#!/bin/bash

if [ "$NDK" = "" ]; then
    echo NDK variable not set, assuming ${HOME}/android-ndk
    export NDK=${HOME}/android-ndk
fi

SYSROOT=$NDK/platforms/android-3/arch-arm
# Expand the prebuilt/* path into the correct one
TOOLCHAIN=`echo $NDK/toolchains/arm-linux-androideabi-4.4.3/prebuilt/*-x86`
export PATH=$TOOLCHAIN/bin:$PATH

rm -rf build/ffmpeg
mkdir -p build/ffmpeg
cd ffmpeg

# Don't build any neon version for now
for version in armv5te armv7a; do

        DEST=../build/ffmpeg
        FLAGS="--target-os=linux --cross-prefix=arm-linux-androideabi- --arch=arm"
        FLAGS="$FLAGS --sysroot=$SYSROOT"
        FLAGS="$FLAGS --soname-prefix=/data/data/net.smartnotes/lib/"
        FLAGS="$FLAGS --enable-shared --disable-symver"
        FLAGS="$FLAGS --enable-small --optimization-flags=-O2"
        FLAGS="$FLAGS --disable-everything --enable-protocol=file"
        FLAGS="$FLAGS --enable-libmp3lame --enable-encoder=nellymoser"

        case "$version" in
                neon)
                    EXTRA_CFLAGS="-march=armv7-a -mfloat-abi=softfp -mfpu=neon"
                    EXTRA_LDFLAGS="-Wl,--fix-cortex-a8"
                    # Runtime choosing neon vs non-neon requires
                    # renamed files
                    ABI="armeabi-v7a"
                    ;;
                armv7a)
                    # I have tried many things here.
                    EXTRA_CFLAGS="-march=armv7-a -mfloat-abi=softfp"
                    EXTRA_LDFLAGS=""
                    ABI="armeabi-v7a"
                    ;;
                *)
                    # I have tried many things here.
                    EXTRA_CFLAGS="-Luser/include"
                    EXTRA_LDFLAGS=""
                    ABI="armeabi"
                    ;;
        esac
        DEST="$DEST/$ABI"
        FLAGS="$FLAGS --prefix=$DEST"

        mkdir -p $DEST
        echo $FLAGS --extra-cflags="$EXTRA_CFLAGS" --extra-ldflags="$EXTRA_LDFLAGS" > $DEST/info.txt
        ./configure $FLAGS --extra-cflags="$EXTRA_CFLAGS" --extra-ldflags="$EXTRA_LDFLAGS" | tee $DEST/configuration.txt
        [ $PIPESTATUS == 0 ] || exit 1
        make clean
        make -j4 || exit 1
        make install || exit 1

done

Answer 1

I saw you were using the project located at http://bambuser.com/opensource

I had the same problem and resolved like this:

1. compile lame for android using https://github.com/intervigilium/liblame

2. this is a small diff between the original build.sh from "bambuser.com" and the one I used:

   3c3,6
   <  export NDK=${HOME}/downloads/android-ndk # r8d
   ---
   > if [ "$NDK" = "" ]; then
   >     echo NDK variable not set, assuming ${HOME}/android-ndk
   >     export NDK=${HOME}/android-ndk
   > fi
   15,16c18
   < #for version in armv5te armv7a; do
   <  for version in         armv7a; do
   ---
   > for version in armv5te armv7a; do
   24c26
   <     FLAGS="$FLAGS --disable-everything --enable-libmp3lame"
   ---
   >     FLAGS="$FLAGS --disable-everything"
   

3. from "intervigilium" project copy the folder liblame/jni/lame to PATH_TO_NDK/platforms/android-3/arch-arm/usr/include

4. from "intervigilium" project copy liblame/libs/armeabi-v7a/liblame.so to PATH_TO_NDK/platforms/android-3/arch-arm/usr/libs and RENAME it in libmp3lame.so.
5. finally run build.sh.

6. you should be fine:

   install prefix            ../build/ffmpeg/armeabi-v7a
   source path               /home/samuele/downloads/ffmpeg/ffmpeg-android/ffmpeg
   C compiler                arm-linux-androideabi-gcc
   ARCH                      arm (generic)
   big-endian                no
   runtime cpu detection     no
   ARMv5TE enabled           yes
   ARMv6 enabled             yes
   ARMv6T2 enabled           yes
   ARM VFP enabled           yes
   IWMMXT enabled            no
   NEON enabled              no
   debug symbols             yes
   strip symbols             yes
   optimizations             small
   static                    yes
   shared                    yes
   postprocessing support    no
   new filter support        yes
   network support           yes
   threading support         pthreads
   SDL support               no
   Sun medialib support      no
   AVISynth enabled          no
   frei0r enabled            no
   libdc1394 support         no
   libdirac enabled          no
   libfaac enabled           no
   libgsm enabled            no
   **libmp3lame enabled        yes**
   libnut enabled            no
   libopencore-amrnb support no
   libopencore-amrwb support no
   libopencv support         no
   libopenjpeg enabled       no
   librtmp enabled           no
   libschroedinger enabled   no
   libspeex enabled          no
   libtheora enabled         no
   libvorbis enabled         no
   libvpx enabled            no
   libx264 enabled           no
   libxavs enabled           no
   libxvid enabled           no
   zlib enabled              no
   bzlib enabled             no
   
   Enabled decoders:
   
   Enabled encoders:
   mpeg2video      nellymoser
   
   Enabled hwaccels:
   
   Enabled parsers:
   
   Enabled demuxers:
   
   Enabled muxers:
   
   Enabled protocols:
   
   Enabled filters:
   buffer
   
   Enabled bsfs:
   
   Enabled indevs:
   
   Enabled outdevs:
   
   License: LGPL version 2.1 or later
   Creating config.mak and config.h...
   libavutil/avconfig.h is unchanged
   

Be aware, I still need to test the resulting FFmpeg build. To say the truth, now I have to learn how to use it in my App... ;)

EDIT: I tried removing --disable-everything and it builds OK the same, with a lot of encoders, decoders etc, but increasing to ~40MB for the build dir.

Answer 2

Instead of changing the include paths, why don't you try copying all the libmp3lame files that were created by 'make install' to the relevant directory where the script will look for them. Insert ECHO statements to find out what exactly the PATH/CFLAGS/LDFLAGS are at the point where you get the error, and copy the files there so it does find them.