Sur d’autres sites (13534)

• Opencv VideoCapture not streaming RTSP link and returns "no frame !"

  6 septembre 2023, par Asadullah Naeem

  I am trying to stream my HikVision IP camera throough python. I am using cv2.VideoCapture("rtsp_link") which works fine on my Laptop but when I try to run the same python script with same Opencv and FFmpeg version it gives me following error :

  


  Error :

  


  [h264 @ 000002124c7f9a40] missing picture in access unit with size 47
[h264 @ 000002124c7f9a40] no frame!


  


  I have so far tried to run this script on 5 computer devices but it gives the same error. I am using the following python script and my Opencv version is 4.6.0.66 and ffmpeg version 2022-06-20-git-56419428a8-essentials_build-www.gyan.dev :

  


  Python Script :

  


  import cv2

# RTSP stream URL
rtsp_url = "rtsp://username:password@ip_address:port/Streaming/Channels/501"

# Open the RTSP stream
cap = cv2.VideoCapture(rtsp_url)

# Check if the stream was successfully opened
if not cap.isOpened():
    print("Failed to open RTSP stream.")
    exit()

# Read and display frames from the stream
while True:
    # Read a frame from the stream
    ret, frame = cap.read()

    # Check if the frame was successfully read
    if not ret:
        print("Failed to read frame from RTSP stream.")
        break

    # Display the frame
    cv2.imshow("RTSP Stream", frame)

    # Exit if 'q' is pressed
    if cv2.waitKey(1) & 0xFF == ord('q'):
        break

# Release the resources
cap.release()
cv2.destroyAllWindows()



  


  Update :

  


  Code runs on a laptop on both wifi and mobile internet (4G) but on other devices rtsp link is accessible only with mobile internet (4G).

  


• How to resize an animated webp？

  23 mai 2023, par shsf

  I want to be able to change the size of a dynamic webp.
Sample picture address : https://postimg.cc/2qpx5bQm
I found this website to do just that : https://ezgif.com/resize

  


  So how can I implement something similar in my own program ?
I tried using ImageMagick7 or ffmpeg5, but failed.

  


  environment :

  


  [developer@Dev_Payment_229 ~]$ cat /etc/redhat-release

  


  CentOS Linux release 7.8.2003 (Core)

  


  1. tried ffmpeg :

  


  [developer@Dev_Payment_229 ~]$ /opt/ffmpeg-5/ffmpeg -i b.webp -vf "scale=320:-1" b_320.webp
ffmpeg version 5.1.1-static https://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2022 the FFmpeg developers
  built with gcc 8 (Debian 8.3.0-6)
  configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gmp --enable-libgme --enable-gray --enable-libaom --enable-libfribidi --enable-libass --enable-libvmaf --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libdav1d --enable-libxvid --enable-libzvbi --enable-libzimg
  libavutil      57. 28.100 / 57. 28.100
  libavcodec     59. 37.100 / 59. 37.100
  libavformat    59. 27.100 / 59. 27.100
  libavdevice    59.  7.100 / 59.  7.100
  libavfilter     8. 44.100 /  8. 44.100
  libswscale      6.  7.100 /  6.  7.100
  libswresample   4.  7.100 /  4.  7.100
  libpostproc    56.  6.100 / 56.  6.100
[webp @ 0x7686f40] skipping unsupported chunk: ANIM
[webp @ 0x7686f40] skipping unsupported chunk: ANMF
    Last message repeated 10 times
[webp @ 0x7686f40] image data not found
[webp_pipe @ 0x7685700] Could not find codec parameters for stream 0 (Video: webp, none): unspecified size
Consider increasing the value for the 'analyzeduration' (0) and 'probesize' (5000000) options
Input #0, webp_pipe, from 'b.webp':
  Duration: N/A, bitrate: N/A
  Stream #0:0: Video: webp, none, 25 fps, 25 tbr, 25 tbn
Stream mapping:
  Stream #0:0 -> #0:0 (webp (native) -> webp (libwebp_anim))
Press [q] to stop, [?] for help
[webp @ 0x7697600] skipping unsupported chunk: ANIM
[webp @ 0x7697600] skipping unsupported chunk: ANMF
    Last message repeated 10 times
[webp @ 0x7697600] image data not found
Error while decoding stream #0:0: Invalid data found when processing input
Cannot determine format of input stream 0:0 after EOF
Error marking filters as finished
Conversion failed!


  


  It seems that ffmpeg cannot recognize this dynamic webp image.

  


  2. tried ImageMagick7

  


  install :

  


   yum -y install libwebp-devel libwebp-tools
[root@Dev_FTP_241 developer]# yum list installed | grep webp
libwebp.x86_64                         0.3.0-11.el7               @updates
libwebp-devel.x86_64                   0.3.0-11.el7               @updates
libwebp-tools.x86_64                   0.3.0-11.el7               @updates



  


  source code: https://github.com/ImageMagick/ImageMagick/archive/refs/tags/7.1.1-0.tar.gz
tar -xvf ImageMagick-7.1.1-0.tar.gz
./configure --with-webp --prefix=/usr/local/imagemagick
make
make install


  


  single webp can be resized :

  


  [root@Dev_FTP_241 developer]#  /usr/local/imagemagick/bin/convert -resize 480  simple.webp simple_480.webp
Decoded /tmp/magick-LNPdXgk2zDpiuU6Qv9CpDups3560EATh. Dimensions: 2160 x 608. Now saving...
Saved file /tmp/magick-Q8JHRZZOXdp1r1x187eftzsFlw8AqAuo


  


  but animated webp failed :

  


  [root@Dev_FTP_241 developer]#  /usr/local/imagemagick/bin/convert -resize 480  b.webp b_480.webp
Error! Decoding of an animated WebP file is not supported.
       Use webpmux to extract the individual frames or
       vwebp to view this image.
Decoding of /tmp/magick-jMiy7ytmAnBzpS8UpafCQ5B44BjDTUSD failed.
Status: 4 (UNSUPPORTED_FEATURE)
convert: delegate failed `'dwebp' -pam '%i' -o '%o'' @ error/delegate.c/InvokeDelegate/1924.
convert: unable to open file '/tmp/magick-D-NMEGWU_a0IypZWwTpYiWIE61nteoig': No such file or directory @ error/constitute.c/ReadImage/786.
convert: no images defined `b_480.webp' @ error/convert.c/ConvertImageCommand/3342.


  


• ffmpeg error in subprocess.run but works in terminal

  6 juin 2023, par 8TM

  I'm creating my own MKV videos and I found a strange bug when I'm using subprocess module from python 3.11.2 to execute FFmpeg command.

  


  My FFmpeg command is running fine in terminal (ends with success) :

  


  ffmpeg -y \
-i input_video_stream.mkv \
-i input_audio_stream_1.ac3 \
-i input_audio_stream_2.ac3 \
-i input_audio_stream_3.ac3 \
-i input_audio_stream_4.ac3 \
-f srt -i input_subtitle_stream_1.srt \
-f srt -i input_subtitle_stream_2.srt \
-map 0 -map 1 -map 2 -map 3 -map 4 -map 5 -map 6 \
-c copy \
-metadata:s:a:0 language=eng -metadata:s:a:0 title="English1" \
-metadata:s:a:1 language=eng -metadata:s:a:1 title="English2" \
-metadata:s:a:2 language=eng -metadata:s:a:2 title="English3" \
-metadata:s:a:3 language=eng -metadata:s:a:3 title="English4" \
-metadata:s:s:0 language=eng -metadata:s:s:0 title="English1" -metadata:s:s:0 mimetype=application/x-ass \
-metadata:s:s:1 language=eng -metadata:s:s:1 title="English2" -metadata:s:s:1 mimetype=application/x-ass \
-disposition:a:0 default -disposition:s:s:0 default \
output_video_with_audio_and_subtitles.mkv


  


  But when I'm running it by in the same terminal (the same session and the same ffmpeg version) by python from subprocess.run(command) :

  


  subprocess.run([
    'ffmpeg', '-y',
    '-i', 'input_video_stream.mkv',
    '-i', 'input_audio_stream_1.ac3',
    '-i', 'input_audio_stream_2.ac3',
    '-i', 'input_audio_stream_3.ac3',
    '-i', 'input_audio_stream_4.ac3',
    '-f', 'srt', '-i', 'input_subtitle_stream_1.srt',
    '-f', 'srt', '-i', 'input_subtitle_stream_2.srt',
    '-map', '0', '-map', '1', '-map', '2', '-map', '3', '-map', '4', '-map', '5', '-map', '6',
    '-c', 'copy',
    '-metadata:s:a:0', 'language=eng', '-metadata:s:a:0', 'title="English1"', 
    '-metadata:s:a:1', 'language=eng', '-metadata:s:a:1', 'title="English2"', 
    '-metadata:s:a:2', 'language=eng', '-metadata:s:a:2', 'title="English3"', 
    '-metadata:s:a:3', 'language=eng', '-metadata:s:a:3', 'title="English4"', 
    '-metadata:s:s:0', 'language=eng', '-metadata:s:s:0', 'title="English1"', 
    '-metadata:s:s:0', 'mimetype=application/x-ass',
    '-metadata:s:s:1', 'language=eng', '-metadata:s:s:1', 'title="English2"', '-metadata:s:s:1', 'mimetype=application/x-ass', 
    '-disposition:a:0 default', '-disposition:s:s:0 default', 
    'output_video_with_audio_and_subtitles.mkv'
])



  


  it fails :

  


  
ffmpeg version 5.1.2-3 Copyright (c) 2000-2022 the FFmpeg developers
  built with gcc 12 (Debian 12.2.0-14)
  configuration : —prefix=/usr —extra-version=3 —toolchain=hardened —libdir=/usr/lib/x86_64-linux-gnu —incdir=/usr/include/x86_64-linux-gnu —arch=amd64 —enable-gpl —disable-stripping —enable-gnutls —enable-ladspa —enable-libaom —enable-libass —enable-libbluray —enable-libbs2b —enable-libcaca —enable-libcdio —enable-libcodec2 —enable-libdav1d —enable-libflite —enable-libfontconfig —enable-libfreetype —enable-libfribidi —enable-libglslang —enable-libgme —enable-libgsm —enable-libjack —enable-libmp3lame —enable-libmysofa —enable-libopenjpeg —enable-libopenmpt —enable-libopus —enable-libpulse —enable-librabbitmq —enable-librist —enable-librubberband —enable-libshine —enable-libsnappy —enable-libsoxr —enable-libspeex —enable-libsrt —enable-libssh —enable-libsvtav1 —enable-libtheora —enable-libtwolame —enable-libvidstab —enable-libvorbis —enable-libvpx —enable-libwebp —enable-libx265 —enable-libxml2 —enable-libxvid —enable-libzimg —enable-libzmq —enable-libzvbi —enable-lv2 —enable-omx —enable-openal —enable-opencl —enable-opengl —enable-sdl2 —disable-sndio —enable-libjxl —enable-pocketsphinx —enable-librsvg —enable-libmfx —enable-libdc1394 —enable-libdrm —enable-libiec61883 —enable-chromaprint —enable-frei0r —enable-libx264 —enable-libplacebo —enable-librav1e —enable-shared
  libavutil      57. 28.100 / 57. 28.100
  libavcodec     59. 37.100 / 59. 37.100
  libavformat    59. 27.100 / 59. 27.100
  libavdevice    59.  7.100 / 59.  7.100
  libavfilter     8. 44.100 /  8. 44.100
  libswscale      6.  7.100 /  6.  7.100
  libswresample   4.  7.100 /  4.  7.100
  libpostproc    56.  6.100 / 56.  6.100
Input #0, matroska,webm, from 'input_video_stream.mkv' :
  Metadata :
    ENCODER : Lavf59.27.100
  Duration : 00:44:19.94, start : 0.000000, bitrate : 22551 kb/s
  Stream #0:0 : Video : h264 (High), yuv420p(tv, bt709, progressive), 1920x1080 [SAR 1:1 DAR 16:9], 23.98 fps, 23.98 tbr, 1k tbn (default)
    Metadata :
      BPS : 22549589
      NUMBER_OF_FRAMES : 63631
      NUMBER_OF_BYTES : 7480665638
      _STATISTICS_WRITING_APP : mkvmerge v56.0.0 ('Strasbourg / St. Denis') 64-bit
      _STATISTICS_WRITING_DATE_UTC : 2023-05-15 08:21:43
      _STATISTICS_TAGS : BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES
      DURATION : 00:44:19.942000000
[ac3 @ 0x55b374ee9e80] Estimating duration from bitrate, this may be inaccurate
Input #1, ac3, from 'input_audio_stream_1.ac3' :
  Duration : 00:44:19.89, start : 0.000000, bitrate : 448 kb/s
  Stream #1:0 : Audio : ac3, 48000 Hz, 5.1(side), fltp, 448 kb/s
[ac3 @ 0x55b37502ef80] Estimating duration from bitrate, this may be inaccurate
Input #2, ac3, from 'input_audio_stream_2.ac3' :
  Duration : 00:44:19.89, start : 0.000000, bitrate : 192 kb/s
  Stream #2:0 : Audio : ac3, 48000 Hz, stereo, fltp, 192 kb/s
[ac3 @ 0x55b374efc900] Estimating duration from bitrate, this may be inaccurate
Input #3, ac3, from 'input_audio_stream_3.ac3' :
  Duration : 00:43:19.18, start : 0.000000, bitrate : 384 kb/s
  Stream #3:0 : Audio : ac3, 48000 Hz, stereo, fltp, 384 kb/s
[ac3 @ 0x55b374fd60c0] Estimating duration from bitrate, this may be inaccurate
Input #4, ac3, from 'input_audio_stream_4.ac3' :
  Duration : 00:43:19.18, start : 0.000000, bitrate : 192 kb/s
  Stream #4:0 : Audio : ac3, 48000 Hz, stereo, fltp, 192 kb/s
Input #5, srt, from 'input_subtitle_stream_1.srt' :
  Duration : N/A, bitrate : N/A
  Stream #5:0 : Subtitle : subrip
Input #6, srt, from 'input_subtitle_stream_2.srt' :
  Duration : N/A, bitrate : N/A
  Stream #6:0 : Subtitle : subrip
[matroska @ 0x55b3751a1940] Invalid stream specifier : a:0 default.
    Last message repeated 1 times


  


  I know it's reporting something with audio ([matroska @ 0x55b3751a1940] Invalid stream specifier : a:0 default. Last message repeated 1 times) but it's probably problem with my ffmpeg command.