Sur d’autres sites (14569)

• Opencv Videocapture fails to read http url videos

  16 mars 2019, par Purav Zumkhawala

  I want to read HTTP URL videos in my Ubuntu system without downloading them. I can do this in windows OS but when I try to run the same code in Ubuntu using the same opencv VideoCapture method it fails to get any frames.

  Why is this so ?

  I have used same opencv version in both Ubuntu and Windows, can anyone guide me towards a workaround, a tutorial using which I can compile opencv and stream url videos or any other library that supports this functionality in Ubuntu ?

  I have tried almost everything but with no productive result which has led me to finally ask this as a question.

  opencv build information :
  
  
  
    OpenCV modules:
  
      To be built:                 calib3d core dnn features2d flann gapi highgui imgcodecs imgproc java_bindings_generator ml objdetect photo python3 python_bindings_generator stitching video videoio
  
      Disabled:                    world
  
      Disabled by dependency:      -
  
      Unavailable:                 java js python2 ts
  
      Applications:                -
  
      Documentation:               NO
  
      Non-free algorithms:         NO
  
  
  
    GUI: 
  
      QT:                          YES (ver 4.8.7 EDITION = OpenSource)
  
        QT OpenGL support:         NO
  
      GTK+:                        NO
  
      VTK support:                 NO
  
  
  
    Media I/O: 
  
      ZLib:                        /lib64/libz.so (ver 1.2.3)
  
      JPEG:                        /opt/libjpeg-turbo/lib64/libjpeg.a (ver 62)
  
      WEBP:                        build (ver encoder: 0x020e)
  
      PNG:                         build (ver 1.6.35)
  
      TIFF:                        build (ver 42 - 4.0.9)
  
      JPEG 2000:                   build (ver 1.900.1)
  
      OpenEXR:                     build (ver 1.7.1)
  
      HDR:                         YES
  
      SUNRASTER:                   YES
  
      PXM:                         YES
  
      PFM:                         YES
  
  
  
    Video I/O:
  
      DC1394:                      NO
  
      FFMPEG:                      YES
  
        avcodec:                   YES (ver 58.21.104)
  
        avformat:                  YES (ver 58.17.101)
  
        avutil:                    YES (ver 56.18.102)
  
        swscale:                   YES (ver 5.2.100)
  
        avresample:                NO
  
      GStreamer:                   NO
  
      v4l/v4l2:                    linux/videodev2.h
  
  
  
    Parallel framework:            pthreads
  
  
  
    Trace:                         YES (with Intel ITT)
  
  
  
    Other third-party libraries:
  
      Lapack:                      NO
  
      Eigen:                       NO
  
      Custom HAL:                  NO
  
      Protobuf:                    build (3.5.1)
  
  
  
    OpenCL:                        YES (no extra features)
  
      Include path:                /io/opencv/3rdparty/include/opencl/1.2
  
      Link libraries:              Dynamic load
  
  
  
    Python 3:
  
      Interpreter:                 /opt/python/cp36-cp36m/bin/python (ver 3.6.5)
  
      Libraries:                   libpython3.6m.a (ver 3.6.5)
  
      numpy:                       /opt/python/cp36-cp36m/lib/python3.6/site-packages/numpy/core/include (ver 1.11.3)
  
      packages path:               lib/python3.6/site-packages
  
  
  
    Python (for build):            /opt/python/cp36-cp36m/bin/python
  
  
  
    Java:                          
  
      ant:                         NO
  
      JNI:                         NO
  
      Java wrappers:               NO
  
      Java tests:                  NO
  
  
  
    Install to:                    /io/_skbuild/linux-x86_64-3.6/cmake-install

• Files created with "ffmpeg hevc_nvenc" do not play on TV. (with video codec SDK 9.1 of nvidia)

  29 janvier 2020, par Dashhh

  Problem

  • Files created with hevc_nvenc do not play on TV. (samsung smart tv, model unknown)
    Related to my ffmpeg build is below.

  FFmpeg build conf

  $ ffmpeg -buildconf
  
      --enable-cuda
  
      --enable-cuvid
  
      --enable-nvenc
  
      --enable-nonfree
  
      --enable-libnpp
  
      --extra-cflags=-I/path/cuda/include
  
      --extra-ldflags=-L/path/cuda/lib64
  
      --prefix=/prefix/ffmpeg_build
  
      --pkg-config-flags=--static
  
      --extra-libs='-lpthread -lm'
  
      --extra-cflags=-I/prefix/ffmpeg_build/include
  
      --extra-ldflags=-L/prefix/ffmpeg_build/lib
  
      --enable-gpl
  
      --enable-nonfree
  
      --enable-version3
  
      --disable-stripping
  
      --enable-avisynth
  
      --enable-libass
  
      --enable-libfontconfig
  
      --enable-libfreetype
  
      --enable-libfribidi
  
      --enable-libgme
  
      --enable-libgsm
  
      --enable-librubberband
  
      --enable-libshine
  
      --enable-libsnappy
  
      --enable-libssh
  
      --enable-libtwolame
  
      --enable-libwavpack
  
      --enable-libzvbi
  
      --enable-openal
  
      --enable-sdl2
  
      --enable-libdrm
  
      --enable-frei0r
  
      --enable-ladspa
  
      --enable-libpulse
  
      --enable-libsoxr
  
      --enable-libspeex
  
      --enable-avfilter
  
      --enable-postproc
  
      --enable-pthreads
  
      --enable-libfdk-aac
  
      --enable-libmp3lame
  
      --enable-libopus
  
      --enable-libtheora
  
      --enable-libvorbis
  
      --enable-libvpx
  
      --enable-libx264
  
      --enable-libx265
  
      --disable-ffplay
  
      --enable-libopenjpeg
  
      --enable-libwebp
  
      --enable-libxvid
  
      --enable-libvidstab
  
      --enable-libopenh264
  
      --enable-zlib
  
      --enable-openssl

  ---

  ffmpeg Command

  • Command about FFmpeg encoding

  ffmpeg -ss 1800 -vsync 0 -hwaccel cuvid -hwaccel_device 0 \
  
  -c:v h264_cuvid -i /data/input.mp4 -t 10 \
  
  -filter_complex "\
  
  [0:v]hwdownload,format=nv12,format=yuv420p,\
  
  scale=iw*2:ih*2" -gpu 0 -c:v hevc_nvenc -pix_fmt yuv444p16le -preset slow -rc cbr_hq -b:v 5000k -maxrate 7000k -bufsize 1000k -acodec aac -ac 2 -dts_delta_threshold 1000 -ab 128k -flags global_header ./makevideo_nvenc_hevc.mp4

  Full log about This Command - check this full log

  The reason for adding "-color_ " in the command is as follows.

  • HDR video after creating bt2020 + smpte2084 video using nvidia hardware accelerator. (I’m studying to make HDR videos. I’m not sure if this is right.)

  How can I make a video using ffmpeg hevc_nvenc and have it play on TV ?

  ---

  Things i’ve done

  Here’s what I’ve researched about why it doesn’t work.
   The header information is not properly included in the resulting video file. So I used a program called nvhsp to add SEI and VUI information inside the video. See below for the commands and logs used.

  nvhsp is open source for writing VUI and SEI bitstrings in raw video. nvhsp link

  # make rawvideo for nvhsp
  
  $  ffmpeg -vsync 0 -hwaccel cuvid -hwaccel_device 0 -c:v h264_cuvid \
  
  -i /data/input.mp4 -t 10 \
  
  -filter_complex "[0:v]hwdownload,format=nv12,\
  
  format=yuv420p,scale=iw*2:ih*2" \
  
  -gpu 0 -c:v hevc_nvenc -f rawvideo output_for_nvhsp.265
  
  
  
  # use nvhsp
  
  $ python nvhsp.py ./output_for_nvhsp.265 -colorprim bt2020 \
  
  -transfer smpte-st-2084 -colormatrix bt2020nc \
  
  -maxcll "1000,300" -videoformat ntsc -full_range tv \
  
  -masterdisplay "G (13250,34500) B (7500,3000 ) R (34000,16000) WP (15635,16450) L (10000000,1)" \
  
  ./after_nvhsp_proc_output.265
  
  
  
  Parsing the infile:
  
  
  
  ==========================
  
  
  
  Prepending SEI data
  
  Starting new SEI NALu ...
  
  SEI message with MaxCLL = 1000 and MaxFall = 300 created in SEI NAL
  
  SEI message Mastering Display Data G (13250,34500) B (7500,3000) R (34000,16000) WP (15635,16450) L (10000000,1) created in SEI NAL
  
  Looking for SPS ......... [232, 22703552]
  
  SPS_Nals_addresses [232, 22703552]
  
  SPS NAL Size 488
  
  Starting reading SPS NAL contents
  
  Reading of SPS NAL finished. Read 448 of SPS NALu data.
  
  
  
  Making modified SPS NALu ...
  
  Made modified SPS NALu-OK
  
  New SEI prepended
  
  Writing new stream ...
  
  Progress: 100%
  
  =====================
  
  Done!
  
  
  
  File nvhsp_after_output.mp4 created.
  
  
  
  # after process
  
  $ ffmpeg -y -f rawvideo -r 25 -s 3840x2160 -pix_fmt yuv444p16le -color_primaries bt2020 -color_trc smpte2084  -colorspace bt2020nc -color_range tv -i ./1/after_nvhsp_proc_output.265 -vcodec copy  ./1/result.mp4 -hide_banner
  
  
  
  Truncating packet of size 49766400 to 3260044
  
  [rawvideo @ 0x40a6400] Estimating duration from bitrate, this may be inaccurate
  
  Input #0, rawvideo, from './1/nvhsp_after_output.265':
  
    Duration: N/A, start: 0.000000, bitrate: 9953280 kb/s
  
      Stream #0:0: Video: rawvideo (Y3[0][16] / 0x10003359), yuv444p16le(tv, bt2020nc/bt2020/smpte2084), 3840x2160, 9953280 kb/s, 25 tbr, 25 tbn, 25 tbc
  
  [mp4 @ 0x40b0440] Could not find tag for codec rawvideo in stream #0, codec not currently supported in container
  
  Could not write header for output file #0 (incorrect codec parameters ?): Invalid argument
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (copy)
  
      Last message repeated 1 times

  Goal

  • I want to generate matadata normally when encoding a video through hevc_nvenc.

  • I want to create a video through hevc_nvenc and play HDR Video on smart tv with 10bit color depth support.

  ---

  Additional

  • Is it normal for ffmpeg hevc_nvenc not to generate metadata in the resulting video file ? or is it a bug ?

  • Please refer to the image below. (*’알 수 없음’ meaning ’unknown’)

    • if you need more detail file info, check this Gist Link (by ffprobe)
      

  • However, if you encode a file in libx265, the attribute information is entered correctly as shown below.

    • if you need more detail file info, check this Gist Link
      

  However, when using hevc_nvenc, all information is missing.

  • i used option -show_streams -show_programs -show_format -show_data -of json -show_frames -show_log 56 at ffprobe

• Merge remote-tracking branch ’cehoyos/master’

  7 mai 2015, par Michael Niedermayer

  Merge remote-tracking branch ’cehoyos/master’
  * cehoyos/master :
  
    lavf/img2dec : Autodetect qdraw images.
  
    lavc/qdrw : Also support real-world qdraw images.
  Merged-by : Michael Niedermayer <michaelni@gmx.at>
  

  • [DH] libavcodec/qdrw.c
  • [DH] libavcodec/version.h
  • [DH] libavformat/Makefile
  • [DH] libavformat/allformats.c
  • [DH] libavformat/img2dec.c
  • [DH] libavformat/version.h