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  • Des sites réalisés avec MediaSPIP

    2 mai 2011, par

    Cette page présente quelques-uns des sites fonctionnant sous MediaSPIP.
    Vous pouvez bien entendu ajouter le votre grâce au formulaire en bas de page.

  • Support audio et vidéo HTML5

    10 avril 2011

    MediaSPIP utilise les balises HTML5 video et audio pour la lecture de documents multimedia en profitant des dernières innovations du W3C supportées par les navigateurs modernes.
    Pour les navigateurs plus anciens, le lecteur flash Flowplayer est utilisé.
    Le lecteur HTML5 utilisé a été spécifiquement créé pour MediaSPIP : il est complètement modifiable graphiquement pour correspondre à un thème choisi.
    Ces technologies permettent de distribuer vidéo et son à la fois sur des ordinateurs conventionnels (...)

  • HTML5 audio and video support

    13 avril 2011, par

    MediaSPIP uses HTML5 video and audio tags to play multimedia files, taking advantage of the latest W3C innovations supported by modern browsers.
    The MediaSPIP player used has been created specifically for MediaSPIP and can be easily adapted to fit in with a specific theme.
    For older browsers the Flowplayer flash fallback is used.
    MediaSPIP allows for media playback on major mobile platforms with the above (...)

Sur d’autres sites (8961)

  • How can I play libvorbis(ogg) streams using ffplay received with udp ?

    31 mars 2017, par crisman

    ffmpeg

    ffmpeg -f dshow -i audio="virtual-audio-capturer" -codec:a libvorbis -b:a 128k -ac 2 -ar 48000 -f mpegts udp://127.0.0.1:1111

    ffplay

    ffplay -codec:a libvorbis -b:a 128k -ar 48000 -ac 2 udp://127.0.0.1:1111

    not playing audio.


    Other codecs play back working, example below.

    aac working

    ffmpeg -f dshow -i audio="virtual-audio-capturer" -codec:a aac -b:a 128k -ac 2 -ar 48000 -f mpegts udp://127.0.0.1:1111
    ffplay -codec:a aac -b:a 128k -ar 48000 -ac 2 udp://127.0.0.1:1111

    opus codec working

    ffmpeg -f dshow -i audio="virtual-audio-capturer" -codec:a libopus -b:a 128k -ac 2 -ar 48000 -f mpegts udp://127.0.0.1:1111
    ffplay -codec:a libopus -b:a 128k -ar 48000 -ac 2 udp://127.0.0.1:1111

    mp3 working

    ffmpeg -f dshow -i audio="virtual-audio-capturer" -codec:a mp3 -b:a 128k -ac 2 -ar 48000 -f mpegts udp://127.0.0.1:1111
    ffplay -codec:a mp3 -b:a 128k -ar 48000 -ac 2 udp://127.0.0.1:1111

    why libvorbis not working ?

    transport success, but can not play, i think.

    // not woring ffplay displayed log
    ffplay.exe -loglevel debug -codec:a vorbis -b:a 128k -ar 48000 -ac 2 -sync audio -i udp://127.0.0.1:1111
    ffplay version N-83781-g3016e91 Copyright (c) 2003-2017 the FFmpeg developers
    built with gcc 6.3.0 (GCC)
    configuration: --enable-gpl --enable-version3 --enable-cuda --enable-cuvid --enable-d3d11va --enable-dxva2 --enable-libmfx --enable-nvenc --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libzimg --enable-lzma --enable-zlib
    libavutil 55. 48.100 / 55. 48.100
    libavcodec 57. 82.102 / 57. 82.102
    libavformat 57. 66.103 / 57. 66.103
    libavdevice 57. 3.100 / 57. 3.100
    libavfilter 6. 74.100 / 6. 74.100
    libswscale 4. 3.101 / 4. 3.101
    libswresample 2. 4.100 / 2. 4.100
    libpostproc 54. 2.100 / 54. 2.100
    [udp @ 0000000000b68700] No default whitelist set sq= 0B f=0/0
    [udp @ 0000000000b68700] end receive buffer size reported is 65536
    [mpegts @ 0000000000b68ac0] Format mpegts probed with size=2048 and score=50
    [mpegts @ 0000000000b68ac0] stream=0 stream_type=6 pid=100 prog_reg_desc=
    [mpegts @ 0000000000b68ac0] Before avformat_find_stream_info() pos: 0 bytes read:8208 seeks:0 nb_streams:1
    [mpegts @ 0000000000b68ac0] probing stream 0 pp:2500
    [mpegts @ 0000000000b68ac0] probing stream 0 pp:2499
    [mpegts @ 0000000000b68ac0] probing stream 0 pp:2498
    [mpegts @ 0000000000b68ac0] probing stream 0 pp:2497
    [mpegts @ 0000000000b68ac0] probing stream 0 pp:2496
    [mpegts @ 0000000000b68ac0] probing stream 0 pp:2495
    [mpegts @ 0000000000b68ac0] probing stream 0 pp:2494= 0B f=0/0
    [mpegts @ 0000000000b68ac0] Probe with size=10038, packets=7 detected mp3 with score=1
    [mpegts @ 0000000000b68ac0] probing stream 0 pp:2493= 0B f=0/0
    [mpegts @ 0000000000b68ac0] probing stream 0 pp:2492= 0B f=0/0
    [mpegts @ 0000000000b68ac0] probing stream 0 pp:2491= 0B f=0/0
    [mpegts @ 0000000000b68ac0] Probe with size=18321, packets=10 detected mp3 with score=1
    [mpegts @ 0000000000b68ac0] probing stream 0 pp:2490= 0B f=0/0
  • Merge commit ’0b5a26e8bcd219efe5da3a6d39b588fabf91f2b9’

    3 avril 2017, par Clément Bœsch
    Merge commit ’0b5a26e8bcd219efe5da3a6d39b588fabf91f2b9’
    

    * commit ’0b5a26e8bcd219efe5da3a6d39b588fabf91f2b9’ : (35 commits)
    qdm2 : Convert to the new bitstream reader
    qcelp : Convert to the new bitstream reader
    pcx : Convert to the new bitstream reader
    opus : Convert to the new bitstream reader
    nellymoser : Convert to the new bitstream reader
    jvdec : Convert to the new bitstream reader
    hqx : Convert to the new bitstream header
    hq_hqa : Convert to the new bitstream reader
    gsm : Convert to the new bitstream reader
    g72x : Convert to the new bitstream reader
    g2meet : Convert to the new bitstream reader
    fraps : Convert to the new bitstream reader
    flashsv : Convert to the new bitstream reader
    faxcompr : Convert to the new bitstream reader
    exr : Convert to the new bitstream reader
    escape130 : Convert to the new bitstream reader
    escape124 : Convert to the new bitstream reader
    dvdsubdec : Convert to the new bitstream reader
    dss_sp : Convert to the new bitstream reader
    cook : Convert to the new bitstream reader
    ...

    This merge is a noop, see
    http://ffmpeg.org/pipermail/ffmpeg-devel/2017-April/209609.html

    Merged-by : Clément Bœsch <u@pkh.me>

    • [DH] doc/libav-merge.txt
  • "undefined reference to av···@···"ffmpeg error,when i cross compile opencv4.5.3 which include ffmpeg lib

    11 mai 2024, par caiping Peng

    everyone,It is sorry to bother you,but i need some help.&#xA;I'm working on an embedded deployment project,doing object detection work to real-time video stream. So I have to port my c++ inference prog to RKNN1808 platform. I compile this program with CMake tool,but I cant finish my work because opencv lib cant be compiled rightly.&#xA;To FFmpeg,my configure commend is following :

    &#xA;

    ./configure --enable-cross-compile --cross-prefix=/home/midsummer/Tool/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin/aarch64-linux-gnu- --target-os=linux --arch=aarch64 --prefix=/usr/local/ffmpeg  --enable-shared&#xA;

    &#xA;

    then I am gonna show you the ffmpeg version :

    &#xA;

    libavutil      56. 70.100&#xA;libavcodec     58.134.100&#xA;libavformat    58. 76.100&#xA;libavdevice    58. 13.100&#xA;libavfilter     7.110.100&#xA;libswscale      5.  9.100&#xA;libswresample   3.  9.100&#xA;libpostproc    55.  9.100&#xA;

    &#xA;

    next ,I use following commend to build cmake project :

    &#xA;

    cmake -D CMAKE_BUILD_TYPE=RELEASE  -D CMAKE_C_COMPILER=/home/midsummer/Tool/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin/aarch64-linux-gnu-gcc -D CMAKE_CXX_COMPILER=/home/midsummer/Tool/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin/aarch64-linux-gnu-g&#x2B;&#x2B; -D BUILD_SHARED_LIBS=ON -D CMAKE_CXX_FLAGS=-fPIC -D CMAKE_C_FLAGS=-fPIC -D CMAKE_EXE_LINKER_FLAGS=-lpthread -ldl -D ENABLE_PIC=ON -D WITH_1394=OFF -D WITH_ARAVIS=OFF -D WITH_ARITH_DEC=ON -D WITH_ARITH_ENC=ON -D WITH_CLP=OFF -D WITH_CUBLAS=OFF -D WITH_CUDA=OFF -D WITH_CUFFT=OFF -D WITH_FFMPEG=ON -D WITH_GSTREAMER=ON -D WITH_GSTREAMER_0_10=OFF -D WITH_HALIDE=OFF -D WITH_HPX=OFF -D WITH_IMGCODEC_HDR=ON -D WITH_IMGCODEC_PXM=ON -D WITH_IMGCODEC_SUNRASTER=ON -D WITH_INF_ENGINE=OFF -D WITH_IPP=OFF -D WITH_ITT=OFF -D WITH_JASPER=ON -D WITH_JPEG=ON -D WITH_LAPACK=ON -D WITH_LIBREALSENSE=OFF -D WITH_NVCUVID=OFF -D WITH_OPENCL=OFF -D WITH_OPENCLAMDBLAS=OFF -D WITH_OPENCLAMDFFT=OFF -D WITH_OPENCL_SVM=OFF -D WITH_OPENEXR=OFF -D WITH_OPENGL=OFF -D WITH_OPENMP=OFF -D WITH_OPENNNI=OFF -D WITH_OPENNNI2=OFF -D WITH_OPENVX=OFF -D WITH_PNG=OFF -D WITH_PROTOBUF=OFF -D WITH_PTHREADS_PF=ON -D WITH_PVAPI=OFF -D WITH_QT=OFF -D WITH_QUIRC=OFF  -D WITH_TBB=OFF -D WITH_TIFF=ON -D WITH_VULKAN=OFF -D WITH_WEBP=ON -D WITH_XIMEA=OFF -D CMAKE_INSTALL_PREFIX=../CrossCompileResult  -D WITH_GTK=OFF  -D BUILD_opencv_dnn=OFF ..&#xA;

    &#xA;

    following is the outpt about FFmpeg :

    &#xA;

    --   Video I/O:&#xA;--     FFMPEG:                      YES&#xA;--       avcodec:                   YES (58.134.100)&#xA;--       avformat:                  YES (58.76.100)&#xA;--       avutil:                    YES (56.70.100)&#xA;--       swscale:                   YES (5.9.100)&#xA;--       avresample:                NO&#xA;--     GStreamer:                   NO&#xA;--     v4l/v4l2:                    YES (linux/videodev2.h)&#xA;&#xA;

    &#xA;

    After building the cmake project,I compiled this project with comment 【make -j16】.After not so long time,I got the Error :

    &#xA;

    [ 49%] Linking CXX executable ../../bin/opencv_annotation&#xA;[ 49%] Building CXX object modules/ts/CMakeFiles/opencv_ts.dir/src/ts_tags.cpp.o&#xA;[ 49%] Built target opencv_annotation&#xA;[ 49%] Linking CXX executable ../../bin/opencv_visualisation&#xA;/home/midsummer/Tool/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin/../lib/gcc/aarch64-linux-gnu/6.3.1/../../../../aarch64-linux-gnu/bin/ld: warning: libavcodec.so.58, needed by ../../lib/libopencv_videoio.so.4.5.3, not found (try using -rpath or -rpath-link)&#xA;/home/midsummer/Tool/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin/../lib/gcc/aarch64-linux-gnu/6.3.1/../../../../aarch64-linux-gnu/bin/ld: warning: libavformat.so.58, needed by ../../lib/libopencv_videoio.so.4.5.3, not found (try using -rpath or -rpath-link)&#xA;/home/midsummer/Tool/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin/../lib/gcc/aarch64-linux-gnu/6.3.1/../../../../aarch64-linux-gnu/bin/ld: warning: libavutil.so.56, needed by ../../lib/libopencv_videoio.so.4.5.3, not found (try using -rpath or -rpath-link)&#xA;/home/midsummer/Tool/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin/../lib/gcc/aarch64-linux-gnu/6.3.1/../../../../aarch64-linux-gnu/bin/ld: warning: libswscale.so.5, needed by ../../lib/libopencv_videoio.so.4.5.3, not found (try using -rpath or -rpath-link)&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_init_packet@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_get_riff_video_tags@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_send_packet@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_receive_packet@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_get_mov_video_tags@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_find_decoder@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_find_decoder_by_name@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_frame_alloc@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_get_name@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwframe_transfer_data@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_malloc@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avio_open@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_alloc_context@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_sub_q@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_network_init@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_packet_free@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_flush_buffers@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_find_encoder@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `sws_getContext@LIBSWSCALE_5&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_receive_frame@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_write_frame@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_close_input@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_seek_frame@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `sws_freeContext@LIBSWSCALE_5&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_dict_set@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_descriptor_get_by_name@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `sws_scale@LIBSWSCALE_5&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_packet_unref@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_dict_parse_string@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_frame_get_buffer@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_freep@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_find_stream_info@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_read_frame@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_free_context@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_default_get_format@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwframe_ctx_init@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_register_all@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_free@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwframe_get_buffer@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_guess_sample_aspect_ratio@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_new_stream@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwframe_constraints_free@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwdevice_ctx_create_derived@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_frame_unref@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_buffer_unref@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_write_trailer@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_packet_rescale_ts@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_bsf_get_by_name@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_send_frame@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_get_hw_config@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_buffer_ref@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_dict_get@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_bsf_free@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_codec_is_decoder@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_open_input@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_lockmgr_register@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_packet_alloc@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwframe_ctx_create_derived@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_bsf_send_packet@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_bsf_alloc@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_log_set_level@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_image_get_buffer_size@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_open2@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_codec_is_encoder@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_guess_format@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_image_fill_arrays@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_bsf_receive_packet@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `sws_getCachedContext@LIBSWSCALE_5&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_codec_get_tag@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwdevice_get_hwframe_constraints@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwdevice_ctx_create@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_codec_iterate@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_log_set_callback@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_opt_set@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_codec_get_id@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_write_header@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_parameters_copy@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_pix_fmt_to_codec_tag@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwframe_ctx_alloc@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_mallocz@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_find_input_format@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_dict_free@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_get_hw_frames_parameters@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwdevice_get_type_name@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avio_close@LIBAVFORMAT_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_frame_free@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_bsf_init@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_close@LIBAVCODEC_58&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwdevice_find_type_by_name@LIBAVUTIL_56&#x27;&#xA;../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_get_context_defaults3@LIBAVCODEC_58&#x27;&#xA;collect2: error: ld returned 1 exit status&#xA;make[2]: *** [apps/visualisation/CMakeFiles/opencv_visualisation.dir/build.make:89: bin/opencv_visualisation] Error 1&#xA;make[1]: *** [CMakeFiles/Makefile2:3357: apps/visualisation/CMakeFiles/opencv_visualisation.dir/all] Error 2&#xA;make[1]: *** Waiting for unfinished jobs....&#xA;[ 49%] Linking CXX shared library ../../lib/libopencv_calib3d.so&#xA;[ 49%] Built target opencv_calib3d&#xA;[ 50%] Linking CXX static library ../../lib/libopencv_ts.a&#xA;[ 50%] Built target opencv_ts&#xA;make: *** [Makefile:163: all] Error 2&#xA;&#xA;

    &#xA;

    I dont know what's wrong with it,It has confused me for a few days,I real hope someone can help me solve the prob.&#xA;I promise the the ffmpeg version match the version of opencv strictly,promising the PKG_CONFIG_PATH is right.

    &#xA;

    I have tried many method like changing opencv version or ffmpeg version,recompiling the ffmpeg,changing PKG_CONFIG_PATH,coping ffmpeg pc file from /usr/local/ffmpeg/lib/pkgconfig to /usr/local/lib/pkgconfig.&#xA;I hope somebody can give some idea about how to solve this problem.

    &#xA;