Recherche avancée

Sur d’autres sites (10863)

• ffmpeg - compilation problem with g++

  22 août 2014, par Sun

  I am trying to run a program which uses ffmpeg libraries to decode a mp3 file. I am using following options for compiling the program :

  g++ -c play.cpp -o play.o
  
  g++ -o play play.o -L/usr/local/lib -lavutil -lavcodec -lavformat -lavdevice \
  
                     -lavfilter -ldl -lasound -L/usr/lib -lSDL -lpthread -lz -lswscale -lm

  But while linking I am gettign following errors :

  play.cpp:(.text+0x49): undefined reference to `av_dup_packet(AVPacket*)'
  
  play.cpp:(.text+0x66): undefined reference to `av_malloc(unsigned int)'
  
  play.cpp:(.text+0x324): undefined reference to `avcodec_decode_audio3(AVCodecContext*, short*, int*, AVPacket*)'
  
  play.cpp:(.text+0x387): undefined reference to `av_free_packet(AVPacket*)'

  and so on...
  These reported functions are available in the libavcodec.a etc. which i have already specified with the link options.
  Can anyone please tell me what could be wrong here or suggest how to approach debugging this ?

• FFmpeg Zoom in and out video every x seconds problem

  6 juillet 2020, par cleanguy

  I want to zoom in 3 seconds every 6 seconds and then zoom out. I can do this, but the sound slips. video zoom periodically What would be the reason ?

  


  ffmpeg -i "test.mp4" -vf "zoompan=z='if(lte(mod(time,4),3),zoom+0.5,zoom-0.2)':x='iw/2-(iw/zoom)/2':y='ih/2-(ih/zoom)/2':d=1:fps=24" -vcodec libx264 -acodec aac -preset ultrafast "rendered/test.mp4"


  


• Have some problem when merging two video files with ffmpeg and xfade filter [closed]

  12 septembre 2023, par song jin

  ffmpeg -i img_1.mp4 -i img_2.mp4 -i img_3.mp4 -i img_4.mp4 -i img_5.mp4 -filter_complex "[0:v]xfade=transition=wiperight:duration=1:offset=4[v0];[1:v]xfade=transition=wiperight:duration=1:offset=8[v1];[2:v]xfade=transition=wiperight:duration=1:offset=1[v2];[3:v]xfade=transition=wiperight:duration=1:offset=1[v3];[v0][v1][v2][v3]concat=n=4:v=1:a=0,format=yuv420p[v]" -map "[v]" -y -s 1920*1080 concat.mp4
I was using this command to merging multiple videos, and then the following problem occurred：

  


  Stream mapping:Stream #0:0 (h264) -> xfade
Stream #1:0 (h264) -> xfade
Stream #1:0 (h264) -> xfade
Stream #2:0 (h264) -> xfade
Stream #2:0 (h264) -> xfade
Stream #3:0 (h264) -> xfade
Stream #3:0 (h264) -> xfade
Stream #4:0 (h264) -> xfade
format:default -> Stream #0:0 (libx264)


  


  As a result, there will be multiple input streams in the video.
How can I solve it ?
I hope have only one input per video stream
I want to have only one input per video stream