Question

I am trying to build ffmpeg with opencore-amr and libx264 support, I found this build script http://sourceforge.net/projects/ffmpeg4android/, this compiles as expected, the resultant binary works fine on the device and –enable-libx264 appears in the output of the binary when I pass no arguments.

However when I try to include support for libopencore-amr it doesnt seem to work, I have installed libopencore-amr and libopencore-amr-devel (I should add that I have tried this whole procedure on both fedora and ubuntu). I modified the Android_Configure.mk file so that it looks like this:

FF_CONFIGURATION_STRING := \
    --arch=$(TARGET_ARCH) \
    --target-os=linux \
    --enable-cross-compile \
    --cross-prefix=$(NDK_CROSS_
PREFIX) \
    --sysroot=$(NDK_SYSROOT) \
    --enable-shared \
    --enable-static \
    --enable-libopencore-amrnb   <-- i've added this line

However when I run ./configure I see:

libopencore-amrnb support no
libopencore-amrwb support no

Despite this the build goes well with zero compilation errors. When I run ffmpeg on the device everything seems to work however there is definitely no support for amrnb.

Answer 1

You have to make sure libopencore exists in the sysroot against which you are compiling, and thats where –sysroot parameter points to. The chance is there is no libopencore there, so configure script disables it.