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ffmpegh.264cuvid

Error while using h264_cuvid decoder with ffmpeg

I am trying to decode a video using the NVIDIA cuvid hardware acceleration with ffmpeg.

I am using a NVIDIA GeForce GT 745M Graphics card (GPU:GK107), which is compatible with cuvid as specified by NVIDIA here

I compiled ffmpeg with the following flags:

./configure --enable-cuda --enable-nvenc --enable-cuvid

Then, I used ffmpeg with the following command line:

ffmpeg.exe -hwaccel cuvid -c:v h264_cuvid -i video.mkv video.mkv

ffmpeg finishes and seems to be unable to open cuvid functions:

Cannot load cuvidGetDecoderCaps
[h264_cuvid @ 07047b80] Failed loading nvcuvid.
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (h264_cuvid) -> h264 (libx264))
  Stream #0:1 -> #0:1 (ac3 (native) -> vorbis (libvorbis))
  Stream #0:3 -> #0:2 (subrip (srt) -> ass (ssa))
Error while opening decoder for input stream #0:0 : Unknown error occurred

In ffmpeg source code, I can find out that this error message is printed by the following macro:

#define LOAD_SYMBOL(fun, tp, symbol)                                \
    do {                                                            \
        if (!((f->fun) = (tp*)dlsym(f->lib, symbol))) {             \
            av_log(NULL, AV_LOG_ERROR, "Cannot load %s\n", symbol); \
            ret = AVERROR_UNKNOWN;                                  \
            goto error;                                             \
        }                                                           \
        av_log(NULL, AV_LOG_TRACE, "Loaded sym: %s\n", symbol);     \
    } while (0)

Which is called by:

static inline int cuvid_load_functions(CuvidFunctions **functions)
{
    GENERIC_LOAD_FUNC_PREAMBLE(CuvidFunctions, cuvid, NVCUVID_LIBNAME);

    LOAD_SYMBOL(cuvidGetDecoderCaps, tcuvidGetDecoderCaps, "cuvidGetDecoderCaps");
    LOAD_SYMBOL(cuvidCreateDecoder, tcuvidCreateDecoder, "cuvidCreateDecoder");
    LOAD_SYMBOL(cuvidDestroyDecoder, tcuvidDestroyDecoder, "cuvidDestroyDecoder");
    LOAD_SYMBOL(cuvidDecodePicture, tcuvidDecodePicture, "cuvidDecodePicture");
#ifdef __CUVID_DEVPTR64
    LOAD_SYMBOL(cuvidMapVideoFrame, tcuvidMapVideoFrame, "cuvidMapVideoFrame64");
    LOAD_SYMBOL(cuvidUnmapVideoFrame, tcuvidUnmapVideoFrame, "cuvidUnmapVideoFrame64");
#else
    LOAD_SYMBOL(cuvidMapVideoFrame, tcuvidMapVideoFrame, "cuvidMapVideoFrame");
    LOAD_SYMBOL(cuvidUnmapVideoFrame, tcuvidUnmapVideoFrame, "cuvidUnmapVideoFrame");
#endif
    LOAD_SYMBOL(cuvidCtxLockCreate, tcuvidCtxLockCreate, "cuvidCtxLockCreate");
    LOAD_SYMBOL(cuvidCtxLockDestroy, tcuvidCtxLockDestroy, "cuvidCtxLockDestroy");
    LOAD_SYMBOL(cuvidCtxLock, tcuvidCtxLock, "cuvidCtxLock");
    LOAD_SYMBOL(cuvidCtxUnlock, tcuvidCtxUnlock, "cuvidCtxUnlock");

    LOAD_SYMBOL(cuvidCreateVideoSource, tcuvidCreateVideoSource, "cuvidCreateVideoSource");
    LOAD_SYMBOL(cuvidCreateVideoSourceW, tcuvidCreateVideoSourceW, "cuvidCreateVideoSourceW");
    LOAD_SYMBOL(cuvidDestroyVideoSource, tcuvidDestroyVideoSource, "cuvidDestroyVideoSource");
    LOAD_SYMBOL(cuvidSetVideoSourceState, tcuvidSetVideoSourceState, "cuvidSetVideoSourceState");
    LOAD_SYMBOL(cuvidGetVideoSourceState, tcuvidGetVideoSourceState, "cuvidGetVideoSourceState");
    LOAD_SYMBOL(cuvidGetSourceVideoFormat, tcuvidGetSourceVideoFormat, "cuvidGetSourceVideoFormat");
    LOAD_SYMBOL(cuvidGetSourceAudioFormat, tcuvidGetSourceAudioFormat, "cuvidGetSourceAudioFormat");
    LOAD_SYMBOL(cuvidCreateVideoParser, tcuvidCreateVideoParser, "cuvidCreateVideoParser");
    LOAD_SYMBOL(cuvidParseVideoData, tcuvidParseVideoData, "cuvidParseVideoData");
    LOAD_SYMBOL(cuvidDestroyVideoParser, tcuvidDestroyVideoParser, "cuvidDestroyVideoParser");

    GENERIC_LOAD_FUNC_FINALE(cuvid);
}

Does anybody know if a specific file is needed by cuvid to load its functions? Any clue to what is wrong here?

Solution

  • I don't have the problem anymore.

    I forgot to use libnpp during ffmpeg compilation.

    My current configuration is :

    ./configure --enable-cuda --enable-nvenc --enable-cuvid --enable-libnpp --extra-cflags=-I<path_to_libnpp_headers> --extra-ldflags=-L<path_to_libnpp_libraries>