Question

I have built ffmpeg for Android using the code and method described at

https://github.com/halfninja/android-ffmpeg-x264

using Ubuntu running in VirtualBox on windows. I then copied libvideokit.so into the Project\libs\armeabi folder of a Windows copy of the provided projects. From there I was able to run the ProjectTest from Eclipse on my Android device. I can see the ffmpeg code being executed but when it gets to the point of opening the input file it gives me the indicated error. I have noticed some discussion of this problem at

FFMpeg on Android, undefined references to libavcodec functions, although it is listed on command line

but the solutions have not helped since the file protocol is enabled in this build and I also tried putting “file:” in front of the filepath to no avail. For completeness I tried setting minimal_featureset=0 to enable all the defaults but this gives me the same error. Below is a snapshot of the logcat from Eclipse showing the output from Videokit with an extra call to LOGE to display the result from av_open_input_file. Any suggestions of things to try would be greatly appreciated.

10-23 11:57:33.888: DEBUG/Videokit(4830): run() called
10-23 11:57:33.888: DEBUG/Videokit(4830): run passing off to main()
10-23 11:57:33.904: DEBUG/Videokit(4830): main(): registering all modules
10-23 11:57:33.927: DEBUG/Videokit(4830): main(): registered everything
10-23 11:57:33.927: DEBUG/Videokit(4830): main(): initting opts
10-23 11:57:33.943: DEBUG/Videokit(4830): main(): initted opts.
10-23 11:57:33.943: ERROR/Videokit(4830): ffmpeg version N-30996-gf925b24, Copyright (c) 2000-2011 the FFmpeg developers
10-23 11:57:33.943: ERROR/Videokit(4830):   built on Oct 21 2011 13:54:03 with gcc 4.4.3
10-23 11:57:33.943: ERROR/Videokit(4830):   configuration: --enable-cross-compile --arch=arm5te --enable-armv5te --target-os=linux --disable-stripping --prefix=../output --disable-neon --enable-version3 --disable-shared --enable-static --enable-gpl --enable-memalign-hack --cc=arm-linux-androideabi-gcc --ld=arm-linux-androideabi-ld --extra-cflags='-fPIC -DANDROID -D__thumb__ -mthumb -Wfatal-errors -Wno-deprecated' --disable-everything --enable-decoder=mjpeg --enable-demuxer=mjpeg --enable-parser=mjpeg --enable-demuxer=image2 --enable-muxer=mp4 --enable-encoder=libx264 --enable-libx264 --enable-decoder=rawvideo --enable-protocol=file --enable-hwaccels --disable-ffmpeg --disable-ffplay --disable-ffprobe --disable-ffserver --disable-network --enable-filter=buffer --enable-filter=buffersink --disable-demuxer=v4l --disable-demuxer=v4l2 --disable-indev=v4l --disable-indev=v4l2 --extra-cflags='-I../x264 -Ivideokit' --extra-ldflags=-L../x264
10-23 11:57:33.943: DEBUG/Videokit(4830): main(): parsing options
10-23 11:57:33.943: DEBUG/Videokit(4830): parse_options has 4 options to parse
10-23 11:57:33.951: ERROR/Videokit(4830): opt_input_file av_open_input_file /mnt/sdcard/fun/snap0000.jpg -2 
10-23 11:57:33.951: ERROR/Videokit(4830): /mnt/sdcard/fun/snap0000.jpg: No such file or directory
10-23 11:57:33.951: ERROR/Videokit(4830): ffmpeg_exit(1) called!

Answer 1

The problem is in permissions. On android we have sdcard mounted with system as owner, but without rwx. But ffmpeg checks that:

avformat/file.c:

static int file_check(URLContext *h, int mask)
{
    struct stat st;
    int ret = stat(h->filename, &st);
    if (ret < 0)
        return AVERROR(errno);

    ret |= st.st_mode&S_IRUSR ? mask&AVIO_FLAG_READ  : 0;
    ret |= st.st_mode&S_IWUSR ? mask&AVIO_FLAG_WRITE : 0;

    return ret;
}

Change this function like this:

static int file_check(URLContext *h, int mask)
{
    struct stat st;
    int ret = stat(h->filename, &st);
    if (ret < 0)
        return AVERROR(errno);

    ret |= st.st_mode&S_IRUSR ? mask&AVIO_FLAG_READ  : 0;
    ret |= st.st_mode&S_IRGRP ? mask&AVIO_FLAG_READ  : 0;
    ret |= st.st_mode&S_IROTH ? mask&AVIO_FLAG_READ  : 0;
    ret |= st.st_mode&S_IWUSR ? mask&AVIO_FLAG_WRITE : 0;
    ret |= st.st_mode&S_IWGRP ? mask&AVIO_FLAG_WRITE  : 0;
    ret |= st.st_mode&S_IWOTH ? mask&AVIO_FLAG_WRITE  : 0;


    return ret;
}

And rebuild your ffmpeg. And that`s it!