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• /usr/include/time.h:243:29 : error : expected identifier or ‘(’ before ‘__const’ [duplicate]

  27 novembre 2019, par user12408787

  This question already has an answer here :

  • FFmpeg : building example C codes
    
    1 answer
    

  When I used gcc to compile program，I meet this error messages，and i have searched answers online，but can not find any results，so I want to ask how to fix this？

• Ffmpeg video length is not as expected

  29 juin 2016, par Karnivaurus

  I have a folder containing 500 images, of that format image0.png, image1.png, ..., image499.png. I want to use ffmpeg to convert these images to a video with a frame rate of 50. This should meant that the total video duration is 10 seconds (= 500 / 50).

  To do this, I used the following command :

  ffmpeg -r 50 -f image2 -i image%1d.png -vcodec libx264 -crf 15 -pix_fmt yuv420p video.mp4

  However, the video which was created, had a duration of 2.5 seconds. Otherwise, the video displays the images correctly, and runs from the beginning to the end as expected.

  Why is the video length not as I would have expected ?

  ---

  The full output from the console is :

  ffmpeg version 2.7.6-0ubuntu0.15.10.1 Copyright (c) 2000-2016 the FFmpeg developers
  
    built with gcc 5.2.1 (Ubuntu 5.2.1-22ubuntu2) 20151010
  
    configuration: --prefix=/usr --extra-version=0ubuntu0.15.10.1 --build-suffix=-ffmpeg --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --enable-shared --disable-stripping --enable-avresample --enable-avisynth --enable-frei0r --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libopenjpeg --enable-openal --enable-libopus --enable-libpulse --enable-librtmp --enable-libschroedinger --enable-libshine --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libxvid --enable-libzvbi --enable-opengl --enable-x11grab --enable-libdc1394 --enable-libiec61883 --enable-libzmq --enable-libssh --enable-libsoxr --enable-libx264 --enable-libopencv --enable-libx265
  
    libavutil      54. 27.100 / 54. 27.100
  
    libavcodec     56. 41.100 / 56. 41.100
  
    libavformat    56. 36.100 / 56. 36.100
  
    libavdevice    56.  4.100 / 56.  4.100
  
    libavfilter     5. 16.101 /  5. 16.101
  
    libavresample   2.  1.  0 /  2.  1.  0
  
    libswscale      3.  1.101 /  3.  1.101
  
    libswresample   1.  2.100 /  1.  2.100
  
    libpostproc    53.  3.100 / 53.  3.100
  
  Input #0, image2, from 'image%1d.png':
  
    Duration: 00:00:10.00, start: 0.000000, bitrate: N/A
  
      Stream #0:0: Video: png, rgb24(pc), 1600x600, 50 fps, 50 tbr, 50 tbn, 50 tbc
  
  [libx264 @ 0x122c6c0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 AVX2 LZCNT BMI2
  
  [libx264 @ 0x122c6c0] profile High, level 3.2
  
  [libx264 @ 0x122c6c0] 264 - core 146 r2555 0c21480 - H.264/MPEG-4 AVC codec - Copyleft 2003-2015 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=12 lookahead_threads=2 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=15.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
  
  Output #0, mp4, to 'video.mp4':
  
    Metadata:
  
      encoder         : Lavf56.36.100
  
      Stream #0:0: Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 1600x600, q=-1--1, 50 fps, 12800 tbn, 50 tbc
  
      Metadata:
  
        encoder         : Lavc56.41.100 libx264
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (png (native) -> h264 (libx264))
  
  Press [q] to stop, [?] for help
  
  frame=   84 fps=0.0 q=23.0 size=      61kB time=00:00:00.52 bitrate= 962.5kbits/frame=  161 fps=160 q=23.0 size=     216kB time=00:00:02.06 bitrate= 860.6kbits/frame=  236 fps=157 q=23.0 size=     438kB time=00:00:03.56 bitrate=1008.2kbits/frame=  315 fps=157 q=23.0 size=     658kB time=00:00:05.14 bitrate=1048.8kbits/frame=  390 fps=155 q=23.0 size=     850kB time=00:00:06.64 bitrate=1048.7kbits/frame=  461 fps=153 q=23.0 size=    1059kB time=00:00:08.06 bitrate=1076.2kbits/frame=  500 fps=145 q=-1.0 Lsize=    1292kB time=00:00:09.96 bitrate=1062.3kbits/s    
  
  video:1285kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.521096%
  
  [libx264 @ 0x122c6c0] frame I:2     Avg QP: 9.48  size: 11840
  
  [libx264 @ 0x122c6c0] frame P:223   Avg QP:16.74  size:  3729
  
  [libx264 @ 0x122c6c0] frame B:275   Avg QP:21.86  size:  1672
  
  [libx264 @ 0x122c6c0] consecutive B-frames:  1.0% 73.6% 10.2% 15.2%
  
  [libx264 @ 0x122c6c0] mb I  I16..4: 51.2% 40.0%  8.7%
  
  [libx264 @ 0x122c6c0] mb P  I16..4:  0.9%  1.7%  0.4%  P16..4:  6.2%  3.6%  2.1%  0.0%  0.0%    skip:85.0%
  
  [libx264 @ 0x122c6c0] mb B  I16..4:  0.2%  0.3%  0.0%  B16..8:  7.8%  2.9%  0.7%  direct: 0.5%  skip:87.5%  L0:44.4% L1:50.3% BI: 5.3%
  
  [libx264 @ 0x122c6c0] 8x8 transform intra:52.1% inter:38.1%
  
  [libx264 @ 0x122c6c0] coded y,uvDC,uvAC intra: 9.7% 0.0% 0.0% inter: 1.8% 0.0% 0.0%
  
  [libx264 @ 0x122c6c0] i16 v,h,dc,p: 50% 41%  3%  6%
  
  [libx264 @ 0x122c6c0] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 44% 12% 36%  2%  1%  1%  1%  4%  0%
  
  [libx264 @ 0x122c6c0] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 41% 25% 21%  3%  1%  2%  1%  5%  1%
  
  [libx264 @ 0x122c6c0] i8c dc,h,v,p: 100%  0%  0%  0%
  
  [libx264 @ 0x122c6c0] Weighted P-Frames: Y:0.0% UV:0.0%
  
  [libx264 @ 0x122c6c0] ref P L0: 69.2%  7.5% 16.7%  6.6%
  
  [libx264 @ 0x122c6c0] ref B L0: 78.0% 20.6%  1.4%
  
  [libx264 @ 0x122c6c0] ref B L1: 96.8%  3.2%
  
  [libx264 @ 0x122c6c0] kb/s:1052.00

• On concatinating two videos in FFmpeg, the output video is far longer than expected

  15 août 2019, par Ngo Van Phuc

  I want to ask about FFmpeg.

  • Video A (time : 00:31:51 - 1280x720)
  • Video B (time : 00:00:22 - 1280x720)
  • output video : (time : 01:20:38)

  The code I use : ffmpeg -f concat -i file-list.txt -c copy outputfile.mp4

  I hear people say, need to encode videos, How to encode video ?

  please help me.