libsubtitle_ass.a(libsubtitle_ass_a-subtitles_provider_libass.o): In function `LibassSubtitlesProvider::DrawSubtitles(AegiVideoFrame&, double)':
subtitles_provider_libass.cpp:(.text+0x9a): undefined reference to `ass_set_frame_size'
subtitles_provider_libass.cpp:(.text+0xe3): undefined reference to `ass_render_frame'
libsubtitle_ass.a(libsubtitle_ass_a-subtitles_provider_libass.o): In function `LibassSubtitlesProvider::LibassSubtitlesProvider()':
subtitles_provider_libass.cpp:(.text+0x2cb): undefined reference to `ass_library_init'
subtitles_provider_libass.cpp:(.text+0x2e8): undefined reference to `ass_set_fonts_dir'
subtitles_provider_libass.cpp:(.text+0x2fd): undefined reference to `ass_set_extract_fonts'
subtitles_provider_libass.cpp:(.text+0x312): undefined reference to `ass_set_style_overrides'
subtitles_provider_libass.cpp:(.text+0x32d): undefined reference to `ass_renderer_init'
subtitles_provider_libass.cpp:(.text+0x34c): undefined reference to `ass_set_font_scale'
subtitles_provider_libass.cpp:(.text+0x367): undefined reference to `ass_set_fonts'
libsubtitle_ass.a(libsubtitle_ass_a-subtitles_provider_libass.o): In function `LibassSubtitlesProvider::LibassSubtitlesProvider()':
subtitles_provider_libass.cpp:(.text+0x3fb): undefined reference to `ass_library_init'
subtitles_provider_libass.cpp:(.text+0x418): undefined reference to `ass_set_fonts_dir'
subtitles_provider_libass.cpp:(.text+0x42d): undefined reference to `ass_set_extract_fonts'
subtitles_provider_libass.cpp:(.text+0x442): undefined reference to `ass_set_style_overrides'
subtitles_provider_libass.cpp:(.text+0x45d): undefined reference to `ass_renderer_init'
subtitles_provider_libass.cpp:(.text+0x47c): undefined reference to `ass_set_font_scale'
subtitles_provider_libass.cpp:(.text+0x497): undefined reference to `ass_set_fonts'
libsubtitle_ass.a(libsubtitle_ass_a-subtitles_provider_libass.o): In function `LibassSubtitlesProvider::LoadSubtitles(AssFile*)':
subtitles_provider_libass.cpp:(.text+0x5a0): undefined reference to `ass_free_track'
subtitles_provider_libass.cpp:(.text+0x5c5): undefined reference to `ass_read_memory'
collect2: ld returned 1 exit status