1
我想编译一个libavcodec的例子。我收到以下错误:链接与libavcodec,仍然看到未定义的引用
[email protected]:~/p/avtest$ g++ main.cpp -o main -lavcodec
main.cpp: In function ‘void audio_decode_example(const char*, const char*)’:
main.cpp:57:15: warning: ‘int avcodec_decode_audio4(AVCodecContext*, AVFrame*, int*, const AVPacket*)’ is deprecated [-Wdeprecated-declarations]
len = avcodec_decode_audio4(c, decoded_frame, &got_frame, &avpkt);
^~~~~~~~~~~~~~~~~~~~~
In file included from main.cpp:1:0:
/usr/include/x86_64-linux-gnu/libavcodec/avcodec.h:4773:5: note: declared here
int avcodec_decode_audio4(AVCodecContext *avctx, AVFrame *frame,
^~~~~~~~~~~~~~~~~~~~~
main.cpp:57:73: warning: ‘int avcodec_decode_audio4(AVCodecContext*, AVFrame*, int*, const AVPacket*)’ is deprecated [-Wdeprecated-declarations]
len = avcodec_decode_audio4(c, decoded_frame, &got_frame, &avpkt);
^
In file included from main.cpp:1:0:
/usr/include/x86_64-linux-gnu/libavcodec/avcodec.h:4773:5: note: declared here
int avcodec_decode_audio4(AVCodecContext *avctx, AVFrame *frame,
^~~~~~~~~~~~~~~~~~~~~
/tmp/ccbXVtbs.o: In function `audio_decode_example(char const*, char const*)':
main.cpp:(.text+0x37): undefined reference to `av_init_packet(AVPacket*)'
main.cpp:(.text+0x63): undefined reference to `avcodec_find_decoder(AVCodecID)'
main.cpp:(.text+0xa4): undefined reference to `avcodec_alloc_context3(AVCodec const*)'
main.cpp:(.text+0xf1): undefined reference to `avcodec_open2(AVCodecContext*, AVCodec const*, AVDictionary**)'
main.cpp:(.text+0x19c): undefined reference to `av_free(void*)'
main.cpp:(.text+0x203): undefined reference to `av_frame_alloc()'
main.cpp:(.text+0x266): undefined reference to `avcodec_decode_audio4(AVCodecContext*, AVFrame*, int*, AVPacket const*)'
main.cpp:(.text+0x2b8): undefined reference to `av_get_bytes_per_sample(AVSampleFormat)'
main.cpp:(.text+0x460): undefined reference to `avcodec_close(AVCodecContext*)'
main.cpp:(.text+0x46c): undefined reference to `av_free(void*)'
main.cpp:(.text+0x47b): undefined reference to `av_frame_free(AVFrame**)'
collect2: error: ld returned 1 exit status
正如你可以看到我与libavcodec
链接,但仍然得到未定义的引用。还有什么我必须链接以获得这些符号定义?
可能重复[什么是未定义的引用/未解析的外部符号错误,以及如何解决它?](https://stackoverflow.com/questions/12573816/what-is-an-undefined-reference-unresolved-外部符号错误和如何-DO-修复) – patatahooligan