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• ffmpeg "select" filter not working with MPEG-4 and "-vcodec copy"

  5 novembre 2013, par Simone Palazzo

  I have an MPEG-4 video, which mediainfo describes as:

  Format                                   : MPEG-4
  Format profile                           : Base Media
  Codec ID                                 : isom
  Overall bit rate                         : 6 772 Kbps
  Writing application                      : Lavf54.6.100
  
  Video
  ID                                       : 1
  Format                                   : AVC
  Format/Info                              : Advanced Video Codec
  Format profile                           : High@L4.1
  Format settings, CABAC                   : Yes
  Format settings, ReFrames                : 4 frames
  Codec ID                                 : avc1
  Codec ID/Info                            : Advanced Video Coding
  Bit rate                                 : 25.0 Mbps
  Frame rate mode                          : Constant
  Frame rate                               : 29.000 fps
  Color space                              : YUV
  Chroma subsampling                       : 4:2:0
  Bit depth                                : 8 bits
  Scan type                                : Progressive
  Bits/(Pixel*Frame)                       : 0.554
  Stream size                              : 500 MiB (98%)
  Writing library                          : x264 core 125
  Encoding settings                        : cabac=1 / ref=3 / deblock=1:0:0 /     nalyse=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=abr / mbtree=1 / bitrate=25000 / ratetol=1.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00
  

  (I removed some useless information)

  What I'd like to do is remove the first, say, 200 frames from the video.

  However, if I try with ffmpeg (version 0.11.1, compiled from source)

  ffmpeg -i video.mp4 -vf select='gte(n\,200)' -vcodec copy -strict -2 out.mp4
  

  it doesn't work, the frames are exactly the same. If I remove the -vcodec copy part, what happens is that the first 190 frames are all the same (equal to the 190th one); so, they're not removed, but replaced with the 190th one.

  If I try the select filter to extract single images from the video, with

  ffmpeg -i video.mp4 -vf "select=gte(n\,200)" %d.jpg
  

  it works alright.

  Does anybody have an idea why this happens?

  Thank you!

• Unrecognized option 'preset' with ubuntu 12.04 and ffmpeg

  5 novembre 2013, par hyperrjas

  I have compiled ffmpeg with the guide How To Compile FFmpeg and x264 on Ubuntu.

  Now I'm trying upload a .mp4 file to encode. However I get this error now:

  ffmpeg version git-2013-11-05-934e489 Copyright (c) 2000-2013 the FFmpeg developers
    built on Nov  5 2013 13:58:43 with gcc 4.6 (Ubuntu/Linaro 4.6.3-1ubuntu5)
    configuration: --enable-gpl --enable-libass --enable-libfaac --enable-libfdk-aac --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-librtmp --enable-libtheora --enable-libvorbis --enable-libvpx --enable-x11grab --enable-nonfree --enable-version3
    libavutil      52. 51.100 / 52. 51.100
    libavcodec     55. 41.100 / 55. 41.100
    libavformat    55. 21.100 / 55. 21.100
    libavdevice    55.  5.100 / 55.  5.100
    libavfilter     3. 90.101 /  3. 90.101
    libswscale      2.  5.101 /  2.  5.101
    libswresample   0. 17.104 /  0. 17.104
    libpostproc    52.  3.100 / 52.  3.100
  Unrecognized option 'preset'.
  Error splitting the argument list: Option not found
  
  Errors: no output file created.
  

  This is the ruby methods to encode:

  case format
    when 'mp4'
     h[:video_codec] = 'libx264'
     h[:audio_codec] = 'libfaac'
     h[:custom] = '-qscale 0 -preset slow -g 30'
    when 'ogv'
     h[:video_codec] = 'libtheora'
     h[:audio_codec] = 'libvorbis'
     h[:custom] = '-b 1500k -ab 160000 -g 30'
    when 'webm'
     h[:video_codec] = 'libvpx'
     h[:audio_codec] = 'libvorbis'
     h[:custom] = '-b 1500k -ab 160000 -f webm -g 30'
  end
  

• Unknown encoder 'libfaac' ubuntu 12.04 and ruby on rails 3

  5 novembre 2013, par hyperrjas

  I'm using carrierwave-video to upload video with my ruby on rails app. But I have this problem when try enconde the video:

  Unknown encoder 'libfaac'
  
  Errors: no output file created.
  

  I have tried with:

  sudo apt-get install libfaac-dev
  

  but I get the same error.

  Updated:

  After compile ffmpeg, I get the same error:

  Metadata:
      major_brand     : mp42
      minor_version   : 0
      compatible_brands: mp42isomavc1
      creation_time   : 2011-10-13 18:54:50
      encoder         : HandBrake 0.9.5 2011010300
    Duration: 00:06:43.28, start: 0.000000, bitrate: 380 kb/s
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 960x600 [SAR 1:1 DAR 8:5], 279 kb/s, 9.25 fps, 25 tbr, 90k tbn, 180k tbc
      Metadata:
        creation_time   : 2011-10-13 18:54:50
        handler_name    : 
      Stream #0:1(eng): Audio: aac (mp4a / 0x6134706D), 48000 Hz, mono, s16, 97 kb/s
      Metadata:
        creation_time   : 2011-10-13 18:54:50
        handler_name    : 
  Please use -q:a or -q:v, -qscale is ambiguous
  Unknown encoder 'libfaac'
  
  Errors: no output file created. 
  

• FFMpeg build -lavdevice error on mac [on hold]

  5 novembre 2013, par Ilya Kharlamov

  I'm trying to build ffmpeg for kxmovie, but in the end I get the message here is:

  Build settings from command line:
      ARCHS = armv7s
      SDKROOT = iphoneos7.0
      SYMROOT = tmp/build
  
  === BUILD TARGET kxmovie OF PROJECT kxmovie WITH CONFIGURATION Release ===
  
  Check dependencies
  
  Libtool tmp/build/Release-iphoneos/libkxmovie.a normal armv7s
      cd /Volumes/Files/Kharlamov/Desktop/kxtorrent/submodules/kxmovie
      setenv IPHONEOS_DEPLOYMENT_TARGET 7.0
      setenv PATH "/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin:/Applications/Xcode.app/Contents/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin"
      /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool -static -arch_only armv7s -syslibroot /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS7.0.sdk -L/Volumes/Files/Kharlamov/Desktop/kxtorrent/submodules/kxmovie/tmp/build/Release-iphoneos -L/Volumes/Files/Kharlamov/Desktop/kxtorrent/submodules/kxmovie/libs -filelist /Volumes/Files/Kharlamov/Desktop/kxtorrent/submodules/kxmovie/tmp/build/kxmovie.build/Release-iphoneos/kxmovie.build/Objects-normal/armv7s/kxmovie.LinkFileList -ObjC -all_load -framework Foundation -framework CoreGraphics -lavcodec -lavdevice -lavformat -lavutil -lswresample -lswscale /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS7.0.sdk/usr/lib/libz.dylib -framework MediaPlayer -framework CoreAudio -framework AudioToolbox -framework Accelerate -framework QuartzCore -framework OpenGLES -o /Volumes/Files/Kharlamov/Desktop/kxtorrent/submodules/kxmovie/tmp/build/Release-iphoneos/libkxmovie.a
  /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: -dynamic not specified, -all_load invalid
  /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: -dynamic not specified the following flags are invalid: -ObjC 
  /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: can't locate file for: -lavdevice
  /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: file: -lavdevice is not an object file (not allowed in a library)
  /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: file: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS7.0.sdk/usr/lib/libz.dylib is a dynamic library, not added to the static library
  /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: file: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS7.0.sdk/usr/lib/libz.dylib is a dynamic library, not added to the static library
  /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: file: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS7.0.sdk/usr/lib/libz.dylib is a dynamic library, not added to the static library
  Command /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool failed with exit code 1
  
  ** BUILD FAILED **
  
  
  The following build commands failed:
      Libtool tmp/build/Release-iphoneos/libkxmovie.a normal armv7s
  (1 failure)
  rake aborted!
  ******** Build failed ********
  

  Help please, what is the problem and how to fix it? P.S. I'm sorry for my english, I'm just learning :)

• ffmpeg unique frames only

  5 novembre 2013, par William

  I have a video sequence (MPEG1) of 30 fps that is decoded in two ways:

  • opencv_ffmpeg returns 30 images per second, but only 5 of them are unique, while all others are clones of the unique ones.

  • proprietary players (MediaPlayer) returns only the 5 unique frames and "holds" them for (1/5) sec each.

  Is there a way to grab only the unique frames that the coder knows and not the total amount the ffmpeg decoder produces to fulfill the fps rate?

  I'm developing a tracker and my tracker is forced to run 6 times slower and do many mistakes due to these "cloned frames".

  Does anyone know any technical term to the problem? Unfortunately, ffmpeg is a black box for an opencv user and the documentation is sparse.