Recherche avancée

Sur d’autres sites (6216)

• Unexpected result from Python re.search for command line output

  23 mai 2020, par Fernando Ortega

  I'm using subprocess.Popen to run an ffmpeg command (in Windows) and then extract the part of the output that has the frame count with a regex expression using re.search. Sometimes, not always, I get the wrong result from search even if the printed command output string clearly shows what I expect.

  



  When I use re.findall I get 2 results, the "wrong" one and the expected one, but in the output string of the command I still only see one option. I'd like to understand why this is happening.

  



  Here's the code I'm running :

  



  import re
import subprocess

# path to video with 300 frames
cmd = r'ffmpeg -i C:\...\300frames_HUD.avi -map 0:v:0 -c copy -f null -'
p = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
output_info = p.communicate()[0]

regex = r'(frame=\s*)([0-9]+)'
search_result = re.search(regex, output_info)
findall_result = re.findall(regex, output_info)
print "SEARCH"
print '0', search_result.group(0)
print '1', search_result.group(1)
print '2', search_result.group(2)

print "FIND ALL"
print findall_result


  



  Here are the results I get :

  



  SEARCH
0 frame=  293
1 frame=  
2 293
FIND ALL
[('frame=  ', '293'), ('frame=  ', '300')]


  



  And here is the printed output_info, the ffmpeg command output I'm searching on :

  



  ffmpeg version git-2020-03-15-c467328 Copyright (c) 2000-2020 the FFmpeg developers
  built with gcc 9.2.1 (GCC) 20200122
  configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-ffnvcodec --enable-cuda-llvm --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt --enable-amf
  libavutil      56. 42.100 / 56. 42.100
  libavcodec     58. 75.100 / 58. 75.100
  libavformat    58. 41.100 / 58. 41.100
  libavdevice    58.  9.103 / 58.  9.103
  libavfilter     7. 77.100 /  7. 77.100
  libswscale      5.  6.101 /  5.  6.101
  libswresample   3.  6.100 /  3.  6.100
  libpostproc    55.  6.100 / 55.  6.100
Input #0, avi, from 'C:\...\300frames_HUD.avi':
  Duration: 00:00:10.00, start: 0.000000, bitrate: 373255 kb/s
    Stream #0:0: Video: rawvideo, bgr24, 960x540, 374496 kb/s, 30 fps, 30 tbr, 30 tbn, 30 tbc
    Metadata:
      title           : V
Output #0, null, to 'pipe:':
  Metadata:
    encoder         : Lavf58.41.100
    Stream #0:0: Video: rawvideo, bgr24, 960x540, q=2-31, 374496 kb/s, 30 fps, 30 tbr, 30 tbn, 30 tbc
    Metadata:
      title           : V
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
Press [q] to stop, [?] for help
frame=  300 fps=0.0 q=-1.0 Lsize=N/A time=00:00:10.00 bitrate=N/A speed=19.4x    
video:455625kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown


  



  I'm essentially looking for the 300 number in frame=  300.
I can reproduce this easily when I execute it inside my IDE (pycharm) twice in a row quickly.

  


• What is a correct way of ffmpeg dshow webcamera properties save and load ?

  12 juin 2020, par C0oo1D

  Command (PS == Windows PowerShell) :

  



  PS D:\> ffmpeg -f dshow -show_video_device_dialog True -video_device_save some_profile.txt -i 'video=MicrosoftR LifeCam Studio(TM)'


  



  FFmpeg Header :

  



  ffmpeg version git-2020-06-04-7f81785 Copyright (c) 2000-2020 the FFmpeg developers
  built with gcc 9.3.1 (GCC) 20200523
  configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libsrt --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --disable-w32threads --enable-libmfx --enable-ffnvcodec --enable-cuda-llvm --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt --enable-amf
  libavutil      56. 49.100 / 56. 49.100
  libavcodec     58. 90.100 / 58. 90.100
  libavformat    58. 44.100 / 58. 44.100
  libavdevice    58.  9.103 / 58.  9.103
  libavfilter     7. 84.100 /  7. 84.100
  libswscale      5.  6.101 /  5.  6.101
  libswresample   3.  6.100 /  3.  6.100
  libpostproc    55.  6.100 / 55.  6.100


  



  Error after OK/Cancel/Close in camera settings dialog (empty file was created). Also tried without dialog - the same problem :

  



  [dshow @ 0715de40] Query for IPersistStream failed.
video=Microsoft® LifeCam Studio(TM): I/O error


  



  I assume that problem at the camera side, but I don't exclude my blindness (didn’t find any examples of saving settings or required command options in the documentation).

  



  Perhaps there is another way to save / load webcamera properties ?

  


• ffmpeg unable to save a frame at specific time

  26 mai 2020, par Gowtham

  I followed Im getting error "deprecated pixel format used, make sure you did set range correctly using ffmpeg".. can someone check my code below ? to save a frame from a video but the saved frame is of timestamp 00:00:00 instead of the given timestamp

  



  $ ffmpeg -i 001\ Introduction.mp4 -ss 00:03:12.00 -vframes 1 side_view.jpg
ffmpeg version 4.2.2 Copyright (c) 2000-2019 the FFmpeg developers
  built with gcc 9.3.0 (Gentoo 9.3.0 p2)
  configuration: --prefix=/usr --libdir=/usr/lib64 --shlibdir=/usr/lib64 --docdir=/usr/share/doc/ffmpeg-4.2.2/html --mandir=/usr/share/man --enable-shared --cc=x86_64-pc-linux-gnu-gcc --cxx=x86_64-pc-linux-gnu-g++ --ar=x86_64-pc-linux-gnu-ar --optflags='-march=native -O2 -pipe' --disable-static --enable-avfilter --enable-avresample --disable-stripping --disable-optimizations --disable-libcelt --disable-indev=oss --disable-indev=jack --disable-outdev=oss --enable-version3 --enable-nonfree --enable-bzlib --disable-runtime-cpudetect --disable-debug --disable-gcrypt --disable-gnutls --enable-gmp --enable-gpl --disable-hardcoded-tables --enable-iconv --disable-libtls --enable-libxml2 --disable-lzma --enable-network --enable-opencl --disable-openssl --enable-postproc --disable-libsmbclient --enable-ffplay --enable-sdl2 --enable-vaapi --enable-vdpau --enable-xlib --enable-libxcb --enable-libxcb-shm --enable-libxcb-xfixes --enable-zlib --disable-libcdio --disable-libiec61883 --disable-libdc1394 --disable-libcaca --disable-openal --enable-opengl --enable-libv4l2 --enable-libpulse --enable-libdrm --disable-libjack --disable-libopencore-amrwb --disable-libopencore-amrnb --disable-libcodec2 --disable-libdav1d --enable-libfdk-aac --enable-libopenjpeg --enable-libbluray --disable-libgme --disable-libgsm --disable-libaribb24 --disable-mmal --disable-libmodplug --enable-libopus --disable-libilbc --disable-librtmp --disable-libssh --disable-libspeex --enable-libsrt --enable-librsvg --disable-ffnvcodec --enable-libvorbis --enable-libvpx --disable-libzvbi --disable-appkit --disable-libbs2b --disable-chromaprint --disable-cuda-llvm --disable-libflite --disable-frei0r --disable-libfribidi --enable-fontconfig --disable-ladspa --enable-libass --disable-libtesseract --enable-lv2 --enable-libfreetype --disable-libvidstab --disable-librubberband --disable-libzmq --disable-libzimg --disable-libsoxr --enable-pthreads --disable-libvo-amrwbenc --enable-libmp3lame --disable-libkvazaar --disable-libaom --disable-libopenh264 --disable-libsnappy --enable-libtheora --disable-libtwolame --disable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --disable-armv5te --disable-armv6 --disable-armv6t2 --disable-neon --disable-vfp --disable-vfpv3 --disable-armv8 --disable-mipsdsp --disable-mipsdspr2 --disable-mipsfpu --disable-altivec --disable-amd3dnow --disable-amd3dnowext --disable-aesni --disable-avx --disable-avx2 --disable-fma3 --disable-fma4 --disable-sse3 --disable-ssse3 --disable-sse4 --disable-sse42 --disable-xop --enable-pic --cpu=host --disable-doc --disable-htmlpages --enable-manpages
  libavutil      56. 31.100 / 56. 31.100
  libavcodec     58. 54.100 / 58. 54.100
  libavformat    58. 29.100 / 58. 29.100
  libavdevice    58.  8.100 / 58.  8.100
  libavfilter     7. 57.100 /  7. 57.100
  libavresample   4.  0.  0 /  4.  0.  0
  libswscale      5.  5.100 /  5.  5.100
  libswresample   3.  5.100 /  3.  5.100
  libpostproc    55.  5.100 / 55.  5.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '001 Introduction.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.12.100
  Duration: 00:09:40.10, start: 0.000000, bitrate: 1981 kb/s
    Stream #0:0(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 1835 kb/s, 30 fps, 30 tbr, 15360 tbn, 60 tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
    Stream #0:2(eng): Subtitle: mov_text (tx3g / 0x67337874), 1280x108, 0 kb/s (default)
    Metadata:
      rotate          : 0
      creation_time   : 2020-05-20T08:15:54.000000Z
File 'side_view.jpg' already exists. Overwrite ? [y/N] y
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> mjpeg (native))
Press [q] to stop, [?] for help
[swscaler @ 0x55e27e819520] deprecated pixel format used, make sure you did set range correctly
Output #0, image2, to 'side_view.jpg':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.29.100
    Stream #0:0(eng): Video: mjpeg, yuvj420p(pc), 1280x720 [SAR 1:1 DAR 16:9], q=2-31, 200 kb/s, 30 fps, 30 tbn, 30 tbc (default)
    Metadata:
      handler_name    : VideoHandler
      encoder         : Lavc58.54.100 mjpeg
    Side data:
      cpb: bitrate max/min/avg: 0/0/200000 buffer size: 0 vbv_delay: -1
frame=    1 fps=0.1 q=5.2 Lsize=N/A time=00:00:00.03 bitrate=N/A speed=0.00313x    
video:44kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown


  



  In the above output, notice time=00:00:00.03 despite the given -ss 00:03:12.00.

  



  Update

  



  ffmpeg -i "001 Introduction.mp4" -ss 00:03:12.00 -vframes 1 -report -copyts side_view.jpg

  



  https://gist.github.com/GowthamKudupudi/d3703f990548819a5bcd5e72bd5c0449