Recherche avancée

Sur d’autres sites (8844)

• Combine multiple video and single audio stream into a single output

  15 janvier 2020, par Prashant Saraswat

  I am trying to record an online meeting.
  During the meeting I will receive continuous audio and intermittent video

  • A. Audio B. Video1 C. Video 2

  The Audio stream will span the length of the call. The video1 and video2 streams will be somewhere in the middle.

  Assuming I know the timestamps for all of these streams, how do I combine them in one video ?

  Consider the scenario where the audio stream starts at Tbegin and ends at Tend. The video1 stream starts at T1 and ends at T2. The video2 stream starts at T3 and ends at T4.

  We can assume that the audio stream is of type mp3 and the other streams are of type mp4

• Removing / Overlaying logo on mp4 video format with ffmpeg on linux

  13 juillet 2016, par SilverShadow

  I’m trying to remove logo from an .mp4 video format with ffmpeg on linux machine without re-encoding (for preserving the same quality) with the following command :

  ffmpeg -i input.mp4 -vf delogo=x=270:y=190:w=40:h=40 -c:a copy output.mp4

  and it give me the following errors :

  Unrecognized option 'vf'

  then a new error came up :

  Unable to find a suitable output format for 'delogo=x=270:y=190:w=40:h=40'

  ffmpeg always updating and it seems that they change command line arguments alot so any material or tutorial i find online seems to get out-dated quickly

  I review their website documentation but can’t get it to work, I think i’m missing something...?

  so what is the correct command line in linux shell also, how to view or find out exactly the area coordinates to be removed before actually removing logo/overlaying it and keep testing every while

  and how to overlay a solid color in certain area instead of removing logo transparently as well ?

• Shotdetect : compiling error ("undefined reference")

  8 juillet 2015, par Voprosnik

  I am using Cygwin and I trying to install the program Shotdetect. I downloaded the source with git and also downloaded, compiled and installed ffmpeg through git.

  Installation of shotdetect doesn’t follow the ./configure && make && make install routine, but a cmake system of which I have no experience. Nonetheless there is a script that automates compiling and installation.

  Near the final stages of the compiling, I get a long series of errors concerning some ffmpeg modules :

  Linking CXX executable shotdetect-cmd.exe
  
  /usr/local/lib/libavformat.a(matroskadec.o): In function `matroska_decode_buffer':
  
  /git/ffmpeg/libavformat/matroskadec.c:1321: undefined reference to `BZ2_bzDecompressInit'
  
  /git/ffmpeg/libavformat/matroskadec.c:1336: undefined reference to `BZ2_bzDecompress'
  
  /git/ffmpeg/libavformat/matroskadec.c:1329: undefined reference to `BZ2_bzDecompressEnd'
  
  /git/ffmpeg/libavformat/matroskadec.c:1339: undefined reference to `BZ2_bzDecompressEnd'
  
  /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_decode_subpacket':
  
  /git/ffmpeg/libavcodec/opusdec.c:374: undefined reference to `swr_is_initialized'
  
  /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_decode_frame':
  
  /git/ffmpeg/libavcodec/opusdec.c:220: undefined reference to `swr_is_initialized'
  
  /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_init_resample':
  
  /git/ffmpeg/libavcodec/opusdec.c:161: undefined reference to `swr_init'
  
  /git/ffmpeg/libavcodec/opusdec.c:167: undefined reference to `swr_convert'
  
  /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_decode_frame':
  
  /git/ffmpeg/libavcodec/opusdec.c:234: undefined reference to `swr_convert'
  
  /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_flush_resample':
  
  /git/ffmpeg/libavcodec/opusdec.c:115: undefined reference to `swr_convert'
  
  /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_decode_subpacket':
  
  /git/ffmpeg/libavcodec/opusdec.c:406: undefined reference to `swr_close'
  
  /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_decode_flush':
  
  /git/ffmpeg/libavcodec/opusdec.c:567: undefined reference to `swr_close'
  
  /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_decode_close':
  
  /git/ffmpeg/libavcodec/opusdec.c:589: undefined reference to `swr_free'
  
  /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_decode_init':
  
  /git/ffmpeg/libavcodec/opusdec.c:642: undefined reference to `swr_alloc'
  
  /usr/local/lib/libavcodec.a(tiff.o): In function `tiff_uncompress_lzma':
  
  /git/ffmpeg/libavcodec/tiff.c:396: undefined reference to `lzma_stream_decoder'
  
  /git/ffmpeg/libavcodec/tiff.c:401: undefined reference to `lzma_code'
  
  /git/ffmpeg/libavcodec/tiff.c:402: undefined reference to `lzma_end'
  
  /usr/local/lib/libavcodec.a(utils.o): In function `recode_subtitle':
  
  /git/ffmpeg/libavcodec/utils.c:2672: undefined reference to `libiconv_open'
  
  /git/ffmpeg/libavcodec/utils.c:2707: undefined reference to `libiconv_close'
  
  /git/ffmpeg/libavcodec/utils.c:2693: undefined reference to `libiconv'
  
  /git/ffmpeg/libavcodec/utils.c:2694: undefined reference to `libiconv'
  
  /git/ffmpeg/libavcodec/utils.c:2707: undefined reference to `libiconv_close'
  
  /git/ffmpeg/libavcodec/utils.c:2707: undefined reference to `libiconv_close'
  
  /git/ffmpeg/libavcodec/utils.c:2707: undefined reference to `libiconv_close'
  
  /usr/local/lib/libavcodec.a(utils.o): In function `avcodec_open2':
  
  /git/ffmpeg/libavcodec/utils.c:1698: undefined reference to `libiconv_open'
  
  /git/ffmpeg/libavcodec/utils.c:1705: undefined reference to `libiconv_close'
  
  collect2: error: ld returned 1 exit status
  
  clang: error: linker (via gcc) command failed with exit code 1 (use -v to see invocation)
  
  CMakeFiles/shotdetect-cmd.dir/build.make:122: recipe for target 'shotdetect-cmd.exe' failed
  
  make[2]: *** [shotdetect-cmd.exe] Error 1
  
  CMakeFiles/Makefile2:95: recipe for target 'CMakeFiles/shotdetect-cmd.dir/all' failed
  
  make[1]: *** [CMakeFiles/shotdetect-cmd.dir/all] Error 2
  
  Makefile:117: recipe for target 'all' failed
  
  make: *** [all] Error 2

  Searching online for similar errors, I found the following proposed solutions

  1) fix pkg-config setup so configure will find out all dependencies ;

  2) build ffmpeg (libavcodec) without external dependencies ;

  3) add external dependencies manually with configure —extra-ldflags

  I guess the problem lies on how i compiled ffmpeg (just configure with no options) but other than that have no idea what to do with either of the above suggestions. Should I recompile ffmpeg with different options ?