How_to_build_ffmpeg_with_openssl.md

April 27, 2018 · View on GitHub

1. Download OpenSSL source from OpenSSL official site

Download openssl-1.0.2o.tar.gz
DO NOT use OpenSSL 1.1.0, because FFmpeg 4.0 is not compatible for now.

2. Use x2on/OpenSSL-for-iPhone to build OpenSSL for iOS

Follow the steps in the README.md of x2on/OpenSSL-for-iPhone to build OpenSSL for iOS.
You need to edit build-libssl.sh since the default version may be others.

# Change default version to 1.0.2o
DEFAULTVERSION="1.0.2o"

3. Copy built OpenSSL include files and libraries into a temporary folder

After built successfully, you will find "include" and "lib" folders.
Copy them into a temporary folder, and you can name it to "openssl".

4. Edit build-ffmpeg.sh file

(1) Download kewlbear/FFmpeg-iOS-build-script

Download kewlbear/FFmpeg-iOS-build-script and you will see the "FFmpeg-iOS-build-script" folder.

(2) Duplicate "build-ffmpeg.sh"

Make a copy of "build-ffmpeg.sh" and rename it to "build-ffmpeg-openssl.sh".

(3) Edit "build-ffmpeg-openssl.sh"

Add the scripts between ##### Add Begin ##### and ##### Add End ##### to build with OpenSSL:


...

##### Change Begin #####
FF_VERSION="4.0"
#####  Change End  #####

...

#FDK_AAC=`pwd`/../fdk-aac-build-script-for-iOS/fdk-aac-ios

##### Add Begin #####
# OpenSSL
OPENSSL=`pwd`/openssl
#####  Add End  #####

CONFIGURE_FLAGS="--enable-cross-compile --disable-debug --disable-programs \
                 --disable-doc --enable-pic"

...

if [ "$FDK_AAC" ]
then
	CONFIGURE_FLAGS="$CONFIGURE_FLAGS --enable-libfdk-aac"
fi

##### Add Begin #####
if [ "$OPENSSL" ]
then
	CONFIGURE_FLAGS="$CONFIGURE_FLAGS --enable-openssl"
fi
#####  Add End  #####

# avresample
#CONFIGURE_FLAGS="$CONFIGURE_FLAGS --enable-avresample"

...

if [ "$FDK_AAC" ]
then
	CFLAGS="$CFLAGS -I$FDK_AAC/include"
	LDFLAGS="$LDFLAGS -L$FDK_AAC/lib"
fi

##### Add Begin #####
if [ "$OPENSSL" ]
then
	CFLAGS="$CFLAGS -I$OPENSSL/include"
	LDFLAGS="$LDFLAGS -L$OPENSSL/lib"
fi
#####  Add End  #####

TMPDIR=${TMPDIR/%\/} $CWD/$SOURCE/configure \

...

5. Move "openssl" folder into "FFmpeg-iOS-build-script" folder

Move the "openssl" folder into the "FFmpeg-iOS-build-script" folder.
Make sure the "build-ffmpeg-openssl.sh" file is under the "FFmpeg-iOS-build-script" folder, too.

6. Edit "audio_convert_neon.S"

This step is especially for FFmpeg 4.0 (armv7/armv7s).
If you are about to compile FFmpeg 4.0 (arm64/i386/x86_64) or lower (armv7/armv7s/arm64/i386/x86_64), you can skip this step.
Open the file "ffmpeg-4.0/libswresample/arm/audio_convert_neon.S".

Delete _swri_oldapi_conv_flt_to_s16_neon: and _swri_oldapi_conv_fltp_to_s16_2ch_neon:.
Change _swri_oldapi_conv_flt_to_s16_neon to X(swri_oldapi_conv_flt_to_s16_neon) and _swri_oldapi_conv_fltp_to_s16_2ch_neon to X(swri_oldapi_conv_fltp_to_s16_2ch_neon).

...

function swri_oldapi_conv_flt_to_s16_neon, export=1
// >> Delete Begin
// _swri_oldapi_conv_flt_to_s16_neon:
// << Delete End
        subs            r2,  r2,  #8
        vld1.32         {q0},     [r1,:128]!
        vcvt.s32.f32    q8,  q0,  #31

...

function swri_oldapi_conv_fltp_to_s16_2ch_neon, export=1
// >> Delete Begin
// _swri_oldapi_conv_fltp_to_s16_2ch_neon:
// << Delete End
        ldm             r1,  {r1, r3}
        subs            r2,  r2,  #8
        vld1.32         {q0},     [r1,:128]!

...

function swri_oldapi_conv_fltp_to_s16_nch_neon, export=1
        cmp             r3,  #2
        itt             lt
        ldrlt           r1,  [r1]
// >> Change Begin
//        blt             _swri_oldapi_conv_flt_to_s16_neon
//        beq             _swri_oldapi_conv_fltp_to_s16_2ch_neon
        blt             X(swri_oldapi_conv_flt_to_s16_neon)
        beq             X(swri_oldapi_conv_fltp_to_s16_2ch_neon)
// << Change End

        push            {r4-r8, lr}
        cmp             r3,  #4
        lsl             r12, r3,  #1
        blt             4f

...