Sur d’autres sites (8224)

• FFMPEG Link error

  30 novembre 2014, par Thomas

  I’m trying to compile a modified version of this transcoding example from the FFMPEG site, I’ve used all the required includes and joined the libs using this :

  INCLUDEPATH += $$(FFMPEG_DEV_PATH)\include
  
      LIBS += -L$$(FFMPEG_DEV_PATH)\lib -lavformat -lavcodec -lavutil -lswscale -liconv -lz -lavfilter

  but I get this linking error that I can’t understand :

    "avio_close(AVIOContext*)", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
    "av_strerror(int, char*, unsigned long)", referenced from:
  
        av_make_error_string(char*, unsigned long, int) in PhVideoEncoder.o
  
    "av_rescale_q(long long, AVRational, AVRational)", referenced from:
  
        PhVideoEncoder::encode_write_frame(AVFrame*, unsigned int, int*) in PhVideoEncoder.o
  
    "av_frame_free(AVFrame**)", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
        PhVideoEncoder::filter_encode_write_frame(AVFrame*, unsigned int) in PhVideoEncoder.o
  
        PhVideoEncoder::encode_write_frame(AVFrame*, unsigned int, int*) in PhVideoEncoder.o
  
    "av_read_frame(AVFormatContext*, AVPacket*)", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
    "avcodec_close(AVCodecContext*)", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
    "avcodec_open2(AVCodecContext*, AVCodec const*, AVDictionary**)", referenced from:
  
        PhVideoEncoder::open_input_file(char const*) in PhVideoEncoder.o
  
        PhVideoEncoder::open_output_file(char const*) in PhVideoEncoder.o
  
    "av_dump_format(AVFormatContext*, int, char const*, int)", referenced from:
  
        PhVideoEncoder::open_input_file(char const*) in PhVideoEncoder.o
  
        PhVideoEncoder::open_output_file(char const*) in PhVideoEncoder.o
  
    "av_frame_alloc()", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
        PhVideoEncoder::filter_encode_write_frame(AVFrame*, unsigned int) in PhVideoEncoder.o
  
    "av_free_packet(AVPacket*)", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
    "av_init_packet(AVPacket*)", referenced from:
  
        PhVideoEncoder::encode_write_frame(AVFrame*, unsigned int, int*) in PhVideoEncoder.o
  
    "av_opt_set_bin(void*, char const*, unsigned char const*, int, int)", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "av_register_all()", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
    "av_rescale_q_rnd(long long, AVRational, AVRational, AVRounding)", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
        PhVideoEncoder::encode_write_frame(AVFrame*, unsigned int, int*) in PhVideoEncoder.o
  
    "av_write_trailer(AVFormatContext*)", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
    "avfilter_graph_free(AVFilterGraph**)", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
    "avfilter_inout_free(AVFilterInOut**)", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "avformat_new_stream(AVFormatContext*, AVCodec const*)", referenced from:
  
        PhVideoEncoder::open_output_file(char const*) in PhVideoEncoder.o
  
    "avformat_open_input(AVFormatContext**, char const*, AVInputFormat*, AVDictionary**)", referenced from:
  
        PhVideoEncoder::open_input_file(char const*) in PhVideoEncoder.o
  
    "avcodec_copy_context(AVCodecContext*, AVCodecContext const*)", referenced from:
  
        PhVideoEncoder::open_output_file(char const*) in PhVideoEncoder.o
  
    "avcodec_find_decoder(AVCodecID)", referenced from:
  
        PhVideoEncoder::open_input_file(char const*) in PhVideoEncoder.o
  
    "avcodec_find_encoder(AVCodecID)", referenced from:
  
        PhVideoEncoder::open_output_file(char const*) in PhVideoEncoder.o
  
    "avfilter_get_by_name(char const*)", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "avfilter_graph_alloc()", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "avfilter_inout_alloc()", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "avformat_close_input(AVFormatContext**)", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
    "avcodec_decode_audio4(AVCodecContext*, AVFrame*, int*, AVPacket const*)", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
    "avcodec_decode_video2(AVCodecContext*, AVFrame*, int*, AVPacket const*)", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
    "avcodec_encode_audio2(AVCodecContext*, AVPacket*, AVFrame const*, int*)", referenced from:
  
        PhVideoEncoder::encode_write_frame(AVFrame*, unsigned int, int*) in PhVideoEncoder.o
  
    "avcodec_encode_video2(AVCodecContext*, AVPacket*, AVFrame const*, int*)", referenced from:
  
        PhVideoEncoder::encode_write_frame(AVFrame*, unsigned int, int*) in PhVideoEncoder.o
  
    "avfilter_graph_config(AVFilterGraph*, void*)", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "avfilter_register_all()", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
    "avformat_free_context(AVFormatContext*)", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
    "avformat_write_header(AVFormatContext*, AVDictionary**)", referenced from:
  
        PhVideoEncoder::open_output_file(char const*) in PhVideoEncoder.o
  
    "av_get_sample_fmt_name(AVSampleFormat)", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "av_buffersink_get_frame(AVFilterContext*, AVFrame*)", referenced from:
  
        PhVideoEncoder::filter_encode_write_frame(AVFrame*, unsigned int) in PhVideoEncoder.o
  
    "avfilter_graph_parse_ptr(AVFilterGraph*, char const*, AVFilterInOut**, AVFilterInOut**, void*)", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "avformat_find_stream_info(AVFormatContext*, AVDictionary**)", referenced from:
  
        PhVideoEncoder::open_input_file(char const*) in PhVideoEncoder.o
  
    "av_interleaved_write_frame(AVFormatContext*, AVPacket*)", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
        PhVideoEncoder::encode_write_frame(AVFrame*, unsigned int, int*) in PhVideoEncoder.o
  
    "av_buffersrc_add_frame_flags(AVFilterContext*, AVFrame*, int)", referenced from:
  
        PhVideoEncoder::filter_encode_write_frame(AVFrame*, unsigned int) in PhVideoEncoder.o
  
    "avfilter_graph_create_filter(AVFilterContext**, AVFilter const*, char const*, char const*, void*, AVFilterGraph*)", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "av_get_default_channel_layout(int)", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "avformat_alloc_output_context2(AVFormatContext**, AVOutputFormat*, char const*, char const*)", referenced from:
  
        PhVideoEncoder::open_output_file(char const*) in PhVideoEncoder.o
  
    "av_get_channel_layout_nb_channels(unsigned long long)", referenced from:
  
        PhVideoEncoder::open_output_file(char const*) in PhVideoEncoder.o
  
    "av_frame_get_best_effort_timestamp(AVFrame const*)", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
    "av_log(void*, int, char const*, ...)", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
        PhVideoEncoder::filter_encode_write_frame(AVFrame*, unsigned int) in PhVideoEncoder.o
  
        PhVideoEncoder::flush_encoder(unsigned int) in PhVideoEncoder.o
  
        PhVideoEncoder::open_input_file(char const*) in PhVideoEncoder.o
  
        PhVideoEncoder::open_output_file(char const*) in PhVideoEncoder.o
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
        PhVideoEncoder::encode_write_frame(AVFrame*, unsigned int, int*) in PhVideoEncoder.o
  
        ...
  
    "av_free(void*)", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
    "av_malloc(unsigned long)", referenced from:
  
        av_malloc_array(unsigned long, unsigned long) in PhVideoEncoder.o
  
    "av_strdup(char const*)", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "avio_open(AVIOContext**, char const*, int)", referenced from:
  
        PhVideoEncoder::open_output_file(char const*) in PhVideoEncoder.o

  I tried looking for missing libraries but with no luck... What am I missing ?

  EDIT

  Thanks to the first answer, I added the extern C stuff but I still face a few errors :

  Undefined symbols for architecture x86_64:
  
    "_av_buffersink_get_frame", referenced from:
  
        PhVideoEncoder::filter_encode_write_frame(AVFrame*, unsigned int) in PhVideoEncoder.o
  
    "_av_buffersrc_add_frame_flags", referenced from:
  
        PhVideoEncoder::filter_encode_write_frame(AVFrame*, unsigned int) in PhVideoEncoder.o
  
    "_avfilter_get_by_name", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "_avfilter_graph_alloc", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "_avfilter_graph_config", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "_avfilter_graph_create_filter", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "_avfilter_graph_free", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
    "_avfilter_graph_parse_ptr", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "_avfilter_inout_alloc", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "_avfilter_inout_free", referenced from:
  
        PhVideoEncoder::init_filter(FilteringContext*, AVCodecContext*, AVCodecContext*, char const*) in PhVideoEncoder.o
  
    "_avfilter_register_all", referenced from:
  
        PhVideoEncoder::PhVideoEncoder(QString) in PhVideoEncoder.o
  
  ld: symbol(s) not found for architecture x86_64

• c++ ffmpeg api get video stream from https link

  16 avril 2014, par Chabloz

  I'm trying to read https video link using the function av_format_open_input() but the function return a negative value.
  Here is my code :

  av_register_all();
  
  avcodec_register_all();
  
  avformat_network_init();
  
  const char * url = "https://r1---sn ...";
  
  
  
  AVFormatContext * pFormatCtx = avformat_alloc_context();
  
  
  
  int ret = avformat_open_input(&pFormatCtx, url, NULL, NULL);

  This code worked with a local file as url but as soon as I give a https url it doesnt work anymore.
  thanks
  [edit]
  I found only this : ffserver.c
  But it uses a .ffm file as input. Any exemple or help on how to implement HttpContext (if HttpContext is needed here) would be great.
  [update]
  I ended using libvlc which seems to be much easier but the way to do it using ffmpeg could still be interesting. See my other post if interested : Get frame from video with libvlc smem and convert it to opencv Mat. (c++)

• Link ffmpeg lib statically in Visual Studio

  24 septembre 2014, par 程栋彬

  I’m trying to use ffmpeg in my C++ project on VS2010, and the ffmpeg dev version provides the lib of .h files. I linked these .libs in my projects and the corresponding .dlls are required when running the .exe file. But I want to link the ffmpeg lib statically and running without .dlls.

  I tryed to compile the ffmpeg source code on windows with Mingw, only resulting on some .a archive files. How to get ffmpeg static .lib files ? And it’s a 64bit program so 64bit static lib is required.