windows - 使用cygwin在windows上编译ffmpeg的问题

Question

我最近在Windows 上编译ffmpeg 遇到了很多麻烦。我目前正在使用 cgywin 终端来运行代码。我已经尝试按照网络上许多最流行的教程进行操作，但似乎无法正常工作。我目前正在使用本教程作为指南 http://www.roman10.net/how-to-build-ffmpeg-for-android/

我在哪里:

我已经创建了一个 bash 脚本

#!/bin/bash

NDK=C:/Users/jrblain/Development/adt-bundle-windows-x86_64-20130514/android-ndk-r9
PLATFORM=$NDK/platforms/android-8/arch-arm/
PREBUILT=$NDK/toolchains/arm-linux-androideabi-4.6/prebuilt/windows-x86_64
function build_one
{
./configure --target-os=linux \
    --prefix=$PREFIX \
    --enable-cross-compile \
    --extra-libs="-lgcc" \
    --arch=arm \
    --cc=$PREBUILT/bin/arm-linux-androideabi-gcc \
    --cross-prefix=$PREBUILT/bin/arm-linux-androideabi- \
    --nm=$PREBUILT/bin/arm-linux-androideabi-nm \
    --sysroot=$PLATFORM \
    --extra-cflags=" -O3 -fpic -DANDROID -DHAVE_SYS_UIO_H=1 -Dipv6mr_interface=ipv6mr_ifindex -fasm -Wno-psabi -fno-short-enums -fno-strict-aliasing -finline-limit=300 $OPTIMIZE_CFLAGS " \
    --disable-shared \
    --enable-static \
    --extra-ldflags="-Wl,-rpath-link=$PLATFORM/usr/lib -L$PLATFORM/usr/lib -nostdlib -lc -lm -ldl -llog" \
    --disable-everything \
    --enable-demuxer=mov \
    --enable-demuxer=h264 \
    --disable-ffplay \
    --enable-protocol=file \
    --enable-avformat \
    --enable-avcodec \
    --enable-decoder=rawvideo \
    --enable-decoder=mjpeg \
    --enable-decoder=h263 \
    --enable-decoder=mpeg4 \
    --enable-decoder=h264 \
    --enable-parser=h264 \
    --disable-network \
    --enable-zlib \
    --disable-avfilter \
    --disable-avdevice \
    $ADDITIONAL_CONFIGURE_FLAG

make clean
make  -j4 install
$PREBUILT/bin/arm-linux-androideabi-ar d libavcodec/libavcodec.a inverse.o
$PREBUILT/bin/arm-linux-androideabi-ld -rpath-link=$PLATFORM/usr/lib -L$PLATFORM/usr/lib  -soname libffmpeg.so -shared -nostdlib  -z,noexecstack -Bsymbolic --whole-archive --no-undefined -o $PREFIX/libffmpeg.so libavcodec/libavcodec.a libavformat/libavformat.a libavutil/libavutil.a libswscale/libswscale.a -lc -lm -lz -ldl -llog  --warn-once  --dynamic-linker=/system/bin/linker $PREBUILT/lib/gcc/arm-linux-androideabi/4.4.3/libgcc.a
}

#arm v6
#CPU=armv6
#OPTIMIZE_CFLAGS="-marm -march=$CPU"
#PREFIX=./android/$CPU 
#ADDITIONAL_CONFIGURE_FLAG=
#build_one

#arm v7vfpv3
CPU=armv7-a
OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=vfpv3-d16 -marm -march=$CPU "
PREFIX=./android/$CPU
ADDITIONAL_CONFIGURE_FLAG=
build_one

#arm v7vfp
#CPU=armv7-a
#OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=vfp -marm -march=$CPU "
#PREFIX=./android/$CPU-vfp
#ADDITIONAL_CONFIGURE_FLAG=
#build_one

#arm v7n
#CPU=armv7-a
#OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=neon -marm -march=$CPU -mtune=cortex-a8"
#PREFIX=./android/$CPU 
#ADDITIONAL_CONFIGURE_FLAG=--enable-neon
#build_one

#arm v6+vfp
#CPU=armv6
#OPTIMIZE_CFLAGS="-DCMP_HAVE_VFP -mfloat-abi=softfp -mfpu=vfp -marm -march=$CPU"
#PREFIX=./android/${CPU}_vfp 
#ADDITIONAL_CONFIGURE_FLAG=
#build_one

然后我按照这篇文章的步骤 4-6 进行操作 Does anyone find this useful? - Compiling FFMPEG on Windows with Cywin and NDK r5其中包括

4 - Open the file 'configure' in the root of the FFMPEG directory in a text editor.

5 - Comment out lines 2073, 2074 and 2075.

6 - Below 2075, add the following line:

TMPDIR=c:/cygwin/tmp

当我在 cgywin 中运行脚本时，我得到了这个结果:

    install prefix            ./android/armv7-a
source path               .
C compiler                C:/Users/jrblain/Development/adt-bundle-windows-x86_64-20130514/android-ndk-r9/toolchains/arm-linux-androideabi-4.6/prebuilt/windows-x86_64/bin/arm-linux-androideabi-gcc
ARCH                      arm (armv7-a)
big-endian                no
runtime cpu detection     yes
ARMv5TE enabled           yes
ARMv6 enabled             yes
ARMv6T2 enabled           yes
VFP enabled               yes
NEON enabled              yes
THUMB enabled             no
debug symbols             yes
strip symbols             yes
optimize for size         no
optimizations             yes
static                    yes
shared                    no
postprocessing support    no
new filter support        no
network support           no
threading support         pthreads
safe bitstream reader     yes
SDL support               no
opencl enabled            no
texi2html enabled         no
perl enabled              no
pod2man enabled           no
makeinfo enabled          no

External libraries:
zlib

Enabled decoders:
h263                    mjpeg                   rawvideo
h264                    mpeg4

Enabled encoders:

Enabled hwaccels:

Enabled parsers:
h263                    h264                    mpeg4video

Enabled demuxers:
h264                    mov

Enabled muxers:

Enabled protocols:
file

Enabled filters:

Enabled bsfs:

Enabled indevs:

Enabled outdevs:

License: LGPL version 2.1 or later
Creating config.mak, config.h, and doc/config.texi...
libavutil/avconfig.h is unchanged

WARNING: C:/Users/jrblain/Development/adt-bundle-windows-x86_64-20130514/android-ndk-r9/toolchains/arm-linux-androideabi-4.6/prebuilt/windows-x86_64/bin/arm-linux-androideabi-pkg-config not found, library detection may fail.
library.mak:105: *** missing separator.  Stop.
library.mak:105: *** missing separator.  Stop.
C:\Users\jrblain\Development\adt-bundle-windows-x86_64-20130514\android-ndk-r9\toolchains\arm-linux-androideabi-4.6\prebuilt\windows-x86_64\bin\arm-linux-androideabi-ld.exe: ,noexecstack: unknown -z option
C:\Users\jrblain\Development\adt-bundle-windows-x86_64-20130514\android-ndk-r9\toolchains\arm-linux-androideabi-4.6\prebuilt\windows-x86_64\bin\arm-linux-androideabi-ld.exe: use the --help option for usage information

此脚本运行后，我在 ffmpeg 文件夹中获得了一些新文件。它们是 .config、config(header)、config.mak、config.fate。 android 文件夹永远不会像它应该的那样创建。我也不确定 library.mak 错误是从哪里来的，因为它是随 ffmpeg 下载而来的。

我不确定在这一切中我哪里出错了。我觉得我使用的是 Windows 会让这个构建过程有所不同。

Answer 1

第一个错误是“警告:C:/.../arm-linux-androideabi-pkg-config 未找到，库检测可能失败。”所以我建议修复路径。

“C:/”不是 POSIX 路径。 Cygwin 程序能够翻译它(带有警告)。

cd 'c:' # works. cd is a built-in command
ls 'c:' # doesn't work
ls 'c:/' # works (edited)

关于 Cygwin 如何映射的文档 POSIX- and Win32-style paths .

根据我的经验，当您混合斜杠和反斜杠或从 Cygwin 调用 Windows native 命令时，您会遇到问题。 Example :

javac -cp "$(cygpath -pw "$CLASSPATH")" hello.java

在我看来，您应该对 POSIX 路径进行硬编码，或者使用以下命令:

cygpath -u 'c:' # the relevant command provided by Cygwin
(cd 'c:' && pwd) # a tip, useful if you want a portable syntax

但也许我完全错了。我想你已经检查过路径了

ls 'C:/Users/jrblain/Development/adt-bundle-windows-x86_64-20130514/android-ndk-r9/toolchains/arm-linux-androideabi-4.6/prebuilt/windows-x86_64/bin/arm-linux-androideabi-pkg-config'

而且我假设您已经检查了 mk 文件的第 105 行(制表和 linux 换行)。