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• Can't set seeker in GSTREAMER cv2, python

  29 avril, par Alperen Ölçer

  I want to skip n seconds forward and backward in gstreamer cv2 capture for recorded videos. But when I use cap_gstreamer.set(cv2.CAP_PROP_POS_FRAMES, fps*skip_second) it resets seeker to beginning of video. How can I solve it ? I wrote an example, used recorded clock video.

  


  import cv2

video_p = '/home/alperenlcr/Videos/clock.mp4'

cap_gstreamer = cv2.VideoCapture(video_p, cv2.CAP_GSTREAMER)
cap_ffmpeg = cv2.VideoCapture(video_p, cv2.CAP_FFMPEG)

fps = cap_gstreamer.get(cv2.CAP_PROP_FPS)
skip_second = 100

im1 = cv2.resize(cap_gstreamer.read()[1], (960, 540))
im1_ffmpeg = cv2.resize(cap_ffmpeg.read()[1], (960, 540))

cap_gstreamer.set(cv2.CAP_PROP_POS_FRAMES, fps*skip_second)
cap_ffmpeg.set(cv2.CAP_PROP_POS_FRAMES, fps*skip_second)

im2 = cv2.resize(cap_gstreamer.read()[1], (960, 540))
im2_ffmpeg = cv2.resize(cap_ffmpeg.read()[1], (960, 540))

merge_gstreamer = cv2.hconcat([im1, im2])
merge_ffmpeg = cv2.hconcat([im1_ffmpeg, im2_ffmpeg])

cv2.imshow(str(skip_second) + ' gstreamer', merge_gstreamer)
cv2.imshow(str(skip_second) + ' ffmpeg', merge_ffmpeg)
cv2.waitKey(0)
cv2.destroyAllWindows()

cap_gstreamer.release()
cap_ffmpeg.release()



  


  Result :


  


  My cv2 build is like :

  


  >>> print(cv2.getBuildInformation())

General configuration for OpenCV 4.8.1 =====================================
  Version control:               4.8.1-dirty

  Extra modules:
    Location (extra):            /home/alperenlcr/SourceInstalls/opencv_contrib/modules
    Version control (extra):     4.8.1

  Platform:
    Timestamp:                   2024-12-02T13:44:58Z
    Host:                        Linux 6.8.0-49-generic x86_64
    CMake:                       3.22.1
    CMake generator:             Unix Makefiles
    CMake build tool:            /usr/bin/gmake
    Configuration:               RELEASE

  CPU/HW features:
    Baseline:                    SSE SSE2 SSE3
      requested:                 SSE3
    Dispatched code generation:  SSE4_1 SSE4_2 FP16 AVX AVX2 AVX512_SKX
      requested:                 SSE4_1 SSE4_2 AVX FP16 AVX2 AVX512_SKX
      SSE4_1 (18 files):         + SSSE3 SSE4_1
      SSE4_2 (2 files):          + SSSE3 SSE4_1 POPCNT SSE4_2
      FP16 (1 files):            + SSSE3 SSE4_1 POPCNT SSE4_2 FP16 AVX
      AVX (8 files):             + SSSE3 SSE4_1 POPCNT SSE4_2 AVX
      AVX2 (37 files):           + SSSE3 SSE4_1 POPCNT SSE4_2 FP16 FMA3 AVX AVX2
      AVX512_SKX (8 files):      + SSSE3 SSE4_1 POPCNT SSE4_2 FP16 FMA3 AVX AVX2 AVX_512F AVX512_COMMON AVX512_SKX

  C/C++:
    Built as dynamic libs?:      NO
    C++ standard:                11
    C++ Compiler:                /usr/bin/c++  (ver 10.5.0)
    C++ flags (Release):         -fsigned-char -ffast-math -W -Wall -Wreturn-type -Wnon-virtual-dtor -Waddress -Wsequence-point -Wformat -Wformat-security -Wmissing-declarations -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Wsuggest-override -Wno-delete-non-virtual-dtor -Wno-comment -Wimplicit-fallthrough=3 -Wno-strict-overflow -fdiagnostics-show-option -Wno-long-long -pthread -fomit-frame-pointer -ffunction-sections -fdata-sections  -msse -msse2 -msse3 -fvisibility=hidden -fvisibility-inlines-hidden -O3 -DNDEBUG  -DNDEBUG
    C++ flags (Debug):           -fsigned-char -ffast-math -W -Wall -Wreturn-type -Wnon-virtual-dtor -Waddress -Wsequence-point -Wformat -Wformat-security -Wmissing-declarations -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Wsuggest-override -Wno-delete-non-virtual-dtor -Wno-comment -Wimplicit-fallthrough=3 -Wno-strict-overflow -fdiagnostics-show-option -Wno-long-long -pthread -fomit-frame-pointer -ffunction-sections -fdata-sections  -msse -msse2 -msse3 -fvisibility=hidden -fvisibility-inlines-hidden -g  -O0 -DDEBUG -D_DEBUG
    C Compiler:                  /usr/bin/cc
    C flags (Release):           -fsigned-char -ffast-math -W -Wall -Wreturn-type -Waddress -Wsequence-point -Wformat -Wformat-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wuninitialized -Wno-comment -Wimplicit-fallthrough=3 -Wno-strict-overflow -fdiagnostics-show-option -Wno-long-long -pthread -fomit-frame-pointer -ffunction-sections -fdata-sections  -msse -msse2 -msse3 -fvisibility=hidden -O3 -DNDEBUG  -DNDEBUG
    C flags (Debug):             -fsigned-char -ffast-math -W -Wall -Wreturn-type -Waddress -Wsequence-point -Wformat -Wformat-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wuninitialized -Wno-comment -Wimplicit-fallthrough=3 -Wno-strict-overflow -fdiagnostics-show-option -Wno-long-long -pthread -fomit-frame-pointer -ffunction-sections -fdata-sections  -msse -msse2 -msse3 -fvisibility=hidden -g  -O0 -DDEBUG -D_DEBUG
    Linker flags (Release):      -Wl,--exclude-libs,libippicv.a -Wl,--exclude-libs,libippiw.a   -Wl,--gc-sections -Wl,--as-needed -Wl,--no-undefined  
    Linker flags (Debug):        -Wl,--exclude-libs,libippicv.a -Wl,--exclude-libs,libippiw.a   -Wl,--gc-sections -Wl,--as-needed -Wl,--no-undefined  
    ccache:                      NO
    Precompiled headers:         NO
    Extra dependencies:          /usr/lib/x86_64-linux-gnu/libjpeg.so /usr/lib/x86_64-linux-gnu/libpng.so /usr/lib/x86_64-linux-gnu/libtiff.so /usr/lib/x86_64-linux-gnu/libz.so /usr/lib/x86_64-linux-gnu/libfreetype.so /usr/lib/x86_64-linux-gnu/libharfbuzz.so Iconv::Iconv m pthread cudart_static dl rt nppc nppial nppicc nppidei nppif nppig nppim nppist nppisu nppitc npps cublas cudnn cufft -L/usr/lib/x86_64-linux-gnu -L/usr/lib/cuda/lib64
    3rdparty dependencies:       libprotobuf ade ittnotify libwebp libopenjp2 IlmImf quirc ippiw ippicv

  OpenCV modules:
    To be built:                 aruco bgsegm bioinspired calib3d ccalib core cudaarithm cudabgsegm cudafeatures2d cudafilters cudaimgproc cudalegacy cudaobjdetect cudaoptflow cudastereo cudawarping cudev datasets dnn dnn_objdetect dnn_superres dpm face features2d flann freetype fuzzy gapi hfs highgui img_hash imgcodecs imgproc intensity_transform line_descriptor mcc ml objdetect optflow phase_unwrapping photo plot python3 quality rapid reg rgbd saliency shape stereo stitching structured_light superres surface_matching text tracking ts video videoio videostab wechat_qrcode xfeatures2d ximgproc xobjdetect xphoto
    Disabled:                    cudacodec world
    Disabled by dependency:      -
    Unavailable:                 alphamat cvv hdf java julia matlab ovis python2 sfm viz
    Applications:                tests perf_tests examples apps
    Documentation:               NO
    Non-free algorithms:         NO

  GUI:                           GTK2
    QT:                          NO
    GTK+:                        YES (ver 2.24.33)
      GThread :                  YES (ver 2.72.4)
      GtkGlExt:                  NO
    OpenGL support:              NO
    VTK support:                 NO

  Media I/O: 
    ZLib:                        /usr/lib/x86_64-linux-gnu/libz.so (ver 1.2.11)
    JPEG:                        /usr/lib/x86_64-linux-gnu/libjpeg.so (ver 80)
    WEBP:                        build (ver encoder: 0x020f)
    PNG:                         /usr/lib/x86_64-linux-gnu/libpng.so (ver 1.6.37)
    TIFF:                        /usr/lib/x86_64-linux-gnu/libtiff.so (ver 42 / 4.3.0)
    JPEG 2000:                   build (ver 2.5.0)
    OpenEXR:                     build (ver 2.3.0)
    HDR:                         YES
    SUNRASTER:                   YES
    PXM:                         YES
    PFM:                         YES

  Video I/O:
    DC1394:                      NO
    FFMPEG:                      YES
      avcodec:                   YES (58.134.100)
      avformat:                  YES (58.76.100)
      avutil:                    YES (56.70.100)
      swscale:                   YES (5.9.100)
      swresample:                YES (3.9.100)
    GStreamer:                   YES (1.20.3)
    v4l/v4l2:                    YES (linux/videodev2.h)

  Parallel framework:            TBB (ver 2021.5 interface 12050)

  Trace:                         YES (with Intel ITT)

  Other third-party libraries:
    Intel IPP:                   2021.8 [2021.8.0]
           at:                   /home/alperenlcr/SourceInstalls/opencv/build/3rdparty/ippicv/ippicv_lnx/icv
    Intel IPP IW:                sources (2021.8.0)
              at:                /home/alperenlcr/SourceInstalls/opencv/build/3rdparty/ippicv/ippicv_lnx/iw
    VA:                          NO
    Lapack:                      NO
    Eigen:                       NO
    Custom HAL:                  NO
    Protobuf:                    build (3.19.1)
    Flatbuffers:                 builtin/3rdparty (23.5.9)

  NVIDIA CUDA:                   YES (ver 11.5, CUFFT CUBLAS NVCUVID NVCUVENC FAST_MATH)
    NVIDIA GPU arch:             86
    NVIDIA PTX archs:

  cuDNN:                         YES (ver 8.6.0)

  OpenCL:                        YES (no extra features)
    Include path:                /home/alperenlcr/SourceInstalls/opencv/3rdparty/include/opencl/1.2
    Link libraries:              Dynamic load

  ONNX:                          NO

  Python 3:
    Interpreter:                 /usr/bin/python3 (ver 3.10.12)
    Libraries:                   /usr/lib/x86_64-linux-gnu/libpython3.10.so (ver 3.10.12)
    numpy:                       /usr/lib/python3/dist-packages/numpy/core/include (ver 1.21.5)
    install path:                lib/python3.10/dist-packages/cv2/python-3.10

  Python (for build):            /usr/bin/python3

  Java:                          
    ant:                         NO
    Java:                        NO
    JNI:                         NO
    Java wrappers:               NO
    Java tests:                  NO

  Install to:                    /usr/local
-----------------------------------------------------------------



  


• The 7 GDPR Principles : A Guide to Compliance

  11 août 2023, par Erin — Analytics Tips, GDPR

  We all knew it was coming. It’s all anyone could talk about — the General Data Protection Regulation (GDPR) took effect on 25 May 2018. 

  You might think five years would have been plenty of time for organisations to achieve compliance, yet many have failed to do so. As of 2022, 81% of French businesses and 95% of American companies were still not compliant.

  If you’re one of these organisations still working on compliance, this blog will provide valuable information about the seven GDPR principles and guide you on your way to compliance. It will also explore how web analytics tools can help organisations improve transparency, ensure data security and achieve GDPR compliance.

  What is GDPR ?

  The European Union (EU) created the General Data Protection Regulation (GDPR) to grant individuals greater control over their data and promote transparency in data processing. 

  Known by many other names across Europe (e.g., RGPD, DSGVO, etc.), the GDPR created a set of rules surrounding the handling of personal data of EU citizens and residents, to make sure organisations aren’t being irresponsible with user names, locations, IP addresses, information gleaned from cookies, and so on. 

  Organisations must assume several responsibilities to achieve GDPR compliance, regardless of their physical location. These obligations include :

  • Respecting user rights
  • Implementing documentation and document retention policies
  • Ensuring data security 

  Why is GDPR compliance important ?

  Data has become a valuable asset for businesses worldwide. The collection and use of data is a feature of almost every sector. However, with increased data usage comes a greater responsibility to protect individuals’ privacy and rights. 

  A YouGov study conducted in 17 key markets found that two in three adults worldwide believe tech corporations across all markets have too much control over their data.

  

  GDPR is the most extensive government framework aiming to tackle the increasing concern over data collection and handling. GDPR safeguards personal data from misuse, unauthorised access and data breaches. It ensures that businesses handle information responsibly and with respect for individual privacy. It also provided a foundation for similar laws to be created in other countries, including China, which is among the least concerned regions (56%), along with Sweden (54%) and Indonesia (56%).

  GDPR has been pivotal in safeguarding personal data and empowering individuals with more control over their information. Compliance with GDPR builds trust between businesses and their customers. Currently, 71% of the countries in the world are covered by data protection and privacy legislation.

  What are the risks of non-compliance ?

  We’ve established the siginficance of GDPR, but what about the implications — what does it mean for your business ? The consequences of non-compliance can be severe and are not worth being lax about. 

  According to Article 83 of the GDPR, you can be penalised up to 4% of your annual global revenue or €20 million, whichever is higher, for violations. For smaller businesses, such substantial fines could be devastating. Non-compliance could even result in legal action from individuals or data protection authorities, leading to further financial losses.

  Potential outcomes are not just legal and financial. GDPR violations can significantly damage your reputation as a company. Non-compliance could also cost you business opportunities if your policies and processes do not comply and, therefore, do not align with potential partners. Customers trust businesses that take data protection seriously over those that do not.

  

  Finally, and perhaps the most timid outcome on the surface, individuals have the right to complain to data protection authorities if they believe you violate their data rights. These complaints can trigger an investigation, and if your business is found to be breaking the rules, you could face all of the consequences mentioned above. 

  You may think it couldn’t happen to you, but GDPR fines have collectively reached over €4 billion and are growing at a notable rate. Fines grew 92% from H1 2021 compared with H1 2022. A record-breaking €1.2 billion fine to Meta in 2023 is the biggest we’ve seen, so far. But smaller businesses can be fined, too. A bank in Hungary was fined €1,560 for not erasing and correcting data when the subject requested it. (Individuals can also be fined in flagrant cases, like a police officer fined €1,400 for using police info for private purposes.)

  

  The 7 GDPR principles and how to comply

  You should now have a good understanding of GDPR, why it’s important and the consequences of not being compliant. 

  Your first step to compliance is to identify the personal data your organisation processes and determine the legal basis for processing each type. You then need to review your data processing activities to ensure they align with the GDPR’s purpose and principles.

  There are seven key principles in Article 5 of the GDPR that govern the lawful processing of personal data :

  Lawfulness, fairness and transparency

  This principle ensures you collect and use data in a legal and transparent way. It must be collected with consent, and you must tell your customers why you need their data. Data processing must be conducted fairly and transparently. 

  How to comply

  • Review your data practices and identify if and why you collect personal data from customers.
    • Learn what personally identifiable information (PII) is.
  • Update your website and forms to include a clear and easy-to-understand explanation of why you need their data and what you’ll use it for.
  • Obtain explicit consent from individuals when processing their sensitive data.
  • Add a cookie consent banner to your website, informing users about the cookies you use and why.
    • Website analytics tools like Google Analytics and Matomo offer the ability to create cookie consent banners and integrate with Consent Management Platforms (CMPs) to manage user consent and privacy settings.
    • Matomo also offers a setting without tracking cookies, in which case you would not need to add the cookie consent banner. 
  • Privacy notices must be accessible at all times. 
  • To ensure your cookies are GDPR compliant, you must :
    • Get consent before using any cookies (except strictly necessary cookies). 
    • Clearly explain what each cookie tracks and its purpose.
    • Document and store user consent.
    • Don’t refuse access to services if users do not consent to the use of certain cookies.
    • Make the consent withdrawal process simple. 

  Use tools like Matomo that can be configured to automatically anonymise data so you don’t process any personal data.

  Purpose limitation

  You can only use data for the specific, legitimate purposes you told your visitors, prospects or customers about at the time of collection. You can’t use it for anything else without asking again. 

  How to comply

  • Define the specific purposes for collecting personal data (e.g., processing orders, sending newsletters).
  • Ensure you don’t use the data for any other purposes without getting explicit consent from the individuals.

  Data minimisation

  Data minimisation means you should only collect the data you need, aligned with the stated purpose. You shouldn’t gather or store more data than necessary. Implementing data minimisation practices ensures compliance and protects against data breaches.

  How to comply

  • Identify the minimum data required for each purpose.
  • Conduct a data audit to identify and eliminate unnecessary data collection points.
  • Don’t ask for unnecessary information or store data that’s not essential for your business operations.
  • Implement data retention policies to delete data when it is no longer required.

  Accuracy

  You are responsible for keeping data accurate and up-to-date at all times. You should have processes to promptly erase or correct any data if you have incorrect information for your customers.

  How to comply

  • Implement a process to regularly review and update customer data.
  • Provide an easy way for customers to request corrections to their data if they find any errors.

  Storage limitation

  Data should not be kept longer than necessary. You should only hold onto it for as long as you have a valid reason, which should be the purpose stated and consented to. Securely dispose of data when it is no longer needed. There is no upper time limit on data storage. 

  How to comply

  • Set clear retention periods for the different types of data you collect.
  • Develop data retention policies and adhere to them consistently.
  • Delete data when it’s no longer needed for the purposes you specified.

  Integrity and confidentiality

  You must take measures to protect data from unauthorised or unlawful access, like keeping it locked away and secure.

  How to comply

  • Securely store personal data with encryption and access controls, and keep it either within the EU or somewhere with similar privacy protections. 
  • Train your staff on data protection and restrict access to data only to those who need it for their work.
  • Conduct regular security assessments and address vulnerabilities promptly.

  Accountability

  Accountability means that you are responsible for complying with the other principles. You must demonstrate that you are following the rules and taking data protection seriously.

  How to comply

  • Appoint a Data Protection Officer (DPO) or someone responsible for data privacy in your company.
  • Maintain detailed records of data processing activities and any data breaches.
  • Data breaches must be reported within 72 hours.

  Compliance with GDPR is an ongoing process, and it’s vital to review and update your practices regularly. 

  What are GDPR rights ?

  Individuals are granted various rights under the GDPR. These rights give them more control over their personal data.

  

  The right to be informed : People can ask why their data is required.

  What to do : Explain why personal data is required and how it will be used.

  The right to access : People can request and access the personal data you hold about them.
  What to do : Provide a copy of the data upon request, free of charge and within one month.

  The right to rectification : If data errors or inaccuracies are found, your customers can ask you to correct them.
  What to do : Promptly update any incorrect information to ensure it is accurate and up-to-date.

  The right to object to processing : Your customers have the right to object to processing their data for certain purposes, like direct marketing.
  What to do : Respect this objection unless you have legitimate reasons for processing the data.

  Rights in relation to automated decision-making and profiling : GDPR gives individuals the right not to be subject to decisions based solely on automated processing, including profiling, if it significantly impacts them.
  What to do : Offer individuals the right to human intervention and express their point of view in such cases.

  The right to be forgotten : Individuals can request the deletion of their data under certain circumstances, such as when the data is no longer necessary or when they withdraw consent.
  What to do : Comply with such requests unless you have a legal obligation to keep the data.

  The right to data portability : People can request their personal data in a commonly used and machine-readable format.
  What to do : Provide the data to the individual if they want to transfer it to another service provider.

  The right to restrict processing : Customers can ask you to temporarily stop processing their data, for example, while they verify its accuracy or when they object to its usage.
  What to do : Store the data during this period but do not process it further.

  Are all website analytics tools GDPR compliant ?

  Unfortunately, not all web analytics tools are built the same. No matter where you are located in the world, if you are processing the personal data of European citizens or residents, you need to fulfil GDPR obligations.

  While your web analytics tool helps you gain valuable insights from your user base and web traffic, they don’t all comply with GDPR. No matter how hard you work to adhere to the seven principles and GDPR rights, using a non-compliant tool means that you’ll never be fully GDPR compliant.

  When using website analytics tools and handling data, you should consider the following :

  Collection of data

  Aligned with the lawfulness, fairness and transparency principle, you must collect consent from visitors for tracking if you are using website analytics tools to collect visitor behavioural data — unless you anonymise data entirely with Matomo.

  

  To provide transparency, you should also clarify the types of data you collect, such as IP addresses, device information and browsing behaviour. Note that data collection aims to improve your website’s performance and understand your audience better.

  Storage of data

  Assure your visitors that you securely store their data and only keep it for as long as necessary, following GDPR’s storage limitation principle. Clearly state the retention periods for different data types and specify when you’ll delete or anonymise it.

  Usage of data

  Make it clear that to comply with the purpose limitation principle, the data you collect will not be used for other purposes beyond website analytics. You should also promise not to share data with third parties for marketing or unrelated activities without their explicit consent. 

  Anonymisation and pseudonymisation

  Features like IP anonymisation to protect users’ privacy are available with GA4 (Google Analytics) and Matomo. Describe how you use these tools and mention that you may use pseudonyms or unique identifiers instead of real names to safeguard personal data further.

  Cookies and consent

  Inform visitors that your website uses cookies and other tracking technologies for analytics purposes. Matomo offers customisable cookie banners and opt-out options that allow users to choose their preferences regarding cookies and tracking, along with cookieless options that don’t require consent banners. 

  Right to access and correct data

  Inform visitors of their rights and provide instructions on requesting information. Describe how to correct inaccuracies in their data and update their preferences.

  Security measures

  Assure visitors that you take data security seriously and have implemented measures to protect their data from unauthorised access or breaches. You can also use this opportunity to highlight any encryption or access controls you use to safeguard data.

  Contact information

  Provide contact details for your company’s Data Protection Officer (DPO) and encourage users to reach out if they have any questions or concerns about their data and privacy.

  When selecting web analytics tools, consider how well they align with GDPR principles. Look for features like anonymisation, consent management options, data retention controls, security measures and data storage within the EU or a similarly privacy-protecting jurisdiction. 

  Matomo offers an advanced GDPR Manager. This is to make sure websites are fully GDPR compliant by giving users the ability to access, withdraw consent, object or erase their data, in addition to the anonymizing features. 

  And finally, when you use Matomo, you have 100% data ownership — stored with us in the EU if you’re using Matomo Cloud or on your own servers with Matomo On-Premise — so you can be data-driven and still be compliant with worldwide privacy laws. We are also trusted across industries as we provide accurate data (no trying to fill in the gaps with AI), a robust API that lets you connect your data to your other tools and cookieless tracking options so you don’t need a cookie consent banner. What’s more, our open-source nature allows you to explore the inner workings, offering the assurance of security firsthand. 

  Ready to become GDPR compliant ?

  Whether you’re an established business or just starting out, if you work with data from EU citizens or residents, then achieving GDPR compliance is essential. It doesn’t need to cost you a fortune or five years to get to compliant status. With the right tools and processes, you can be on top of the privacy requirements in no time at all, avoiding any of those hefty penalties or the resulting damage to your reputation. 

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• OpenCV 3.4.3 - GStream not called when VideoWriting

  14 décembre 2018, par taubhi

  I’d like to succeed writing a file with OpenCV encoding with GStreamer.

  Thus I’m using the code :

  VideoWriter.open("appsrc ! autovideoconvert ! omxh264enc ! matroskamux ! filesink location=test2.mkv sync=false",
  
  //cv::CAP_GSTREAMER, //set or not, I get the same problem
  
  0, (double)25, //fourcc, fps
  
  cv::Size(1024, 1024), 
  
  true);

  And my problem :

  A video file called appsrc ! autovideoconvert ! omxh264enc ! matroskamux ! filesink location=test2.mkv sync=false is created (rather than test2.mkv), and it is empty. The same problem is corrected and seems to work in the following thread, without any effect for me : Opening a GStreamer pipeline from OpenCV with VideoWriter

  I tried, without success :

  • Add quotes to the file name test2 :
    "appsrc ! autovideoconvert ! omxh264enc ! matroskamux ! filesink location=\"test2.mkv\" sync=false" neither
  • Encode with different format : .flv rather than .mkv
  • Encode with different codec : omxh265enc rather than omxh264en

  I checked :

  • That GStreamer is well compiled with OpenCV ; the CMake of the OpenCV project outputs :

    Video I/O:Video for Windows : YES
    DC1394 : NO
    FFMPEG : YES (prebuilt binaries)
    avcodec : YES (ver 57.107.100)
    avformat : YES (ver 57.83.100)
    avutil : YES (ver 55.78.100)
    swscale : YES (ver 4.8.100)
    avresample : YES (ver 3.7.0)
    GStreamer :

    base : YES (ver 1.0)

    video : YES (ver 1.0)

    app : YES (ver 1.0)

    riff : YES (ver 1.0)

    pbutils : YES (ver 1.0)

    DirectShow : YES

    Media Foundation : YES

  • That FFMpeg is installed on my computer ; for this I used VLC :

    File -> Stream -> Add a file then stream
    New destination : RTP/MPEG Transport Stream
    Profile : Video - H.264 + MP3 (MP4)
    Then no error happens ; Note : an error occured with Video - H.265 + MP3
    (MP4), but I’m using omxh264enc in my code, not 265

  I’m struggled :/ Do you have any idea ?
  Thanks a lot :)

  Have a good day,

  Thibaut

  PS - Complete OpenCV CMake output :

  Selecting Windows SDK version 10.0.17134.0 to target Windows 10.0.17763.
  
  AVX_512F is not supported by C++ compiler
  
  
  
  AVX512_SKX is not supported by C++ compiler
  
  
  
  Dispatch optimization AVX512_SKX is not available, skipped
  
  
  
  libjpeg-turbo: VERSION = 1.5.3, BUILD = opencv-3.4.3-libjpeg-turbo
  
  
  
  Looking for Mfapi.h
  
  
  
  Looking for Mfapi.h - found
  
  
  
  found Intel IPP (ICV version): 2017.0.3 [2017.0.3]
  
  
  
  at: E:/OpenCV/3.4.3/build-cuda92-gstreamer/3rdparty/ippicv/ippicv_win
  
  
  
  found Intel IPP IW sources: 2017.0.3
  
  
  
  at: E:/OpenCV/3.4.3/build-cuda92-gstreamer/3rdparty/ippicv/ippiw_win
  
  
  
  CUDA detected: 9.2
  
  
  
  CUDA NVCC target flags: -gencode;arch=compute_30,code=sm_30;-gencode;arch=compute_35,code=sm_35;-gencode;arch=compute_37,code=sm_37;-gencode;arch=compute_50,code=sm_50;-gencode;arch=compute_52,code=sm_52;-gencode;arch=compute_60,code=sm_60;-gencode;arch=compute_61,code=sm_61;-gencode;arch=compute_70,code=sm_70;-D_FORCE_INLINES
  
  
  
  Found apache ant: C:/NVPACK/apache-ant-1.8.2/bin/ant.bat (1.8.2)
  
  
  
  Could NOT find Matlab (missing: MATLAB_MEX_SCRIPT MATLAB_INCLUDE_DIRS MATLAB_ROOT_DIR MATLAB_LIBRARIES MATLAB_LIBRARY_DIRS MATLAB_MEXEXT MATLAB_ARCH MATLAB_BIN)
  
  
  
  VTK is not found. Please set -DVTK_DIR in CMake to VTK build directory, or to VTK install subdirectory with VTKConfig.cmake file
  
  
  
  Caffe: NO
  
  
  
  Protobuf: NO
  
  
  
  Glog: YES
  
  
  
  freetype2: NO
  
  
  
  harfbuzz: NO
  
  
  
  Module opencv_ovis disabled because OGRE3D was not found
  
  
  
  No preference for use of exported gflags CMake configuration set, and no hints for include/library directories provided. Defaulting to preferring an installed/exported gflags CMake configuration if available.
  
  
  
  Found installed version of gflags: E:/Git/gflags/BUILD-VS2015
  
  
  
  Detected gflags version: 2.2.1
  
  
  
  Checking SFM deps... FALSE
  
  
  
  Module opencv_sfm disabled because the following dependencies are not found: Eigen Glog/Gflags
  
  
  
  Excluding from source files list: <build>/modules/dnn/layers/layers_common.avx512_skx.cpp
  
  
  
  Tesseract: NO
  
  
  
  
  
  General configuration for OpenCV 3.4.3 =====================================
  
  
  
  Version control: unknown
  
  
  
  
  
  Extra modules:
  
  
  
  Location (extra): E:/OpenCV/3.4.3/opencv_contrib-3.4.3/modules
  
  
  
  Version control (extra): unknown
  
  
  
  
  
  Platform:
  
  
  
  Timestamp: 2018-11-07T16:57:18Z
  
  
  
  Host: Windows 10.0.17763 AMD64
  
  
  
  CMake: 3.12.0-rc2
  
  
  
  CMake generator: Visual Studio 14 2015 Win64
  
  
  
  CMake build tool: C:/Program Files (x86)/MSBuild/14.0/bin/MSBuild.exe
  
  
  
  MSVC: 1900
  
  
  
  
  
  CPU/HW features:
  
  
  
  Baseline: SSE SSE2 SSE3
  
  
  
  requested: SSE3
  
  
  
  Dispatched code generation: SSE4_1 SSE4_2 FP16 AVX AVX2
  
  
  
  requested: SSE4_1 SSE4_2 AVX FP16 AVX2 AVX512_SKX
  
  
  
  SSE4_1 (5 files): + SSSE3 SSE4_1
  
  
  
  SSE4_2 (2 files): + SSSE3 SSE4_1 POPCNT SSE4_2
  
  
  
  FP16 (2 files): + SSSE3 SSE4_1 POPCNT SSE4_2 FP16 AVX
  
  
  
  AVX (6 files): + SSSE3 SSE4_1 POPCNT SSE4_2 AVX
  
  
  
  AVX2 (11 files): + SSSE3 SSE4_1 POPCNT SSE4_2 FP16 FMA3 AVX AVX2
  
  
  
  
  
  C/C++:
  
  
  
  Built as dynamic libs?: YES
  
  
  
  C++11: YES
  
  
  
  C++ Compiler: C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/bin/x86_amd64/cl.exe (ver 19.0.24215.1)
  
  
  
  C++ flags (Release): /DWIN32 /D_WINDOWS /W4 /GR /D _CRT_SECURE_NO_DEPRECATE /D _CRT_NONSTDC_NO_DEPRECATE /D _SCL_SECURE_NO_WARNINGS /Gy /bigobj /Oi /EHa /wd4127 /wd4251 /wd4324 /wd4275 /wd4512 /wd4589 /MP16 /MD /O2 /Ob2 /DNDEBUG
  
  
  
  C++ flags (Debug): /DWIN32 /D_WINDOWS /W4 /GR /D _CRT_SECURE_NO_DEPRECATE /D _CRT_NONSTDC_NO_DEPRECATE /D _SCL_SECURE_NO_WARNINGS /Gy /bigobj /Oi /EHa /wd4127 /wd4251 /wd4324 /wd4275 /wd4512 /wd4589 /MP16 /MDd /Zi /Ob0 /Od /RTC1
  
  
  
  C Compiler: C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/bin/x86_amd64/cl.exe
  
  
  
  C flags (Release): /DWIN32 /D_WINDOWS /W3 /D _CRT_SECURE_NO_DEPRECATE /D _CRT_NONSTDC_NO_DEPRECATE /D _SCL_SECURE_NO_WARNINGS /Gy /bigobj /Oi /MP16 /MD /O2 /Ob2 /DNDEBUG
  
  
  
  C flags (Debug): /DWIN32 /D_WINDOWS /W3 /D _CRT_SECURE_NO_DEPRECATE /D _CRT_NONSTDC_NO_DEPRECATE /D _SCL_SECURE_NO_WARNINGS /Gy /bigobj /Oi /MP16 /MDd /Zi /Ob0 /Od /RTC1
  
  
  
  Linker flags (Release): /machine:x64 /INCREMENTAL:NO
  
  
  
  Linker flags (Debug): /machine:x64 /debug /INCREMENTAL
  
  
  
  ccache: NO
  
  
  
  Precompiled headers: YES
  
  
  
  Extra dependencies: cudart.lib nppc.lib nppial.lib nppicc.lib nppicom.lib nppidei.lib nppif.lib nppig.lib nppim.lib nppist.lib nppisu.lib nppitc.lib npps.lib cublas.lib cufft.lib -LIBPATH:C:/Program Files/NVIDIA GPU Computing Toolkit/CUDA/v9.2/lib/x64
  
  
  
  3rdparty dependencies:
  
  
  
  
  
  OpenCV modules:
  
  
  
  To be built: aruco bgsegm bioinspired calib3d ccalib core cudaarithm cudabgsegm cudacodec cudafeatures2d cudafilters cudaimgproc cudalegacy cudaobjdetect cudaoptflow cudastereo cudawarping cudev datasets dnn dnn_objdetect dpm face features2d flann fuzzy hfs highgui img_hash imgcodecs imgproc java java_bindings_generator line_descriptor ml objdetect optflow phase_unwrapping photo plot python_bindings_generator reg rgbd saliency shape stereo stitching structured_light superres surface_matching text tracking ts video videoio videostab xfeatures2d ximgproc xobjdetect xphoto
  
  
  
  Disabled: js world
  
  
  
  Disabled by dependency: -
  
  
  
  Unavailable: cnn_3dobj cvv freetype hdf matlab ovis python2 python3 sfm viz
  
  
  
  Applications: tests perf_tests apps
  
  
  
  Documentation: NO
  
  
  
  Non-free algorithms: NO
  
  
  
  
  
  Windows RT support: NO
  
  
  
  
  
  GUI:
  
  
  
  Win32 UI: YES
  
  
  
  VTK support: NO
  
  
  
  
  
  Media I/O:
  
  
  
  ZLib: build (ver 1.2.11)
  
  
  
  JPEG: build-libjpeg-turbo (ver 1.5.3-62)
  
  
  
  WEBP: build (ver encoder: 0x020e)
  
  
  
  PNG: build (ver 1.6.34)
  
  
  
  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
  
  
  
  
  
  Video I/O:
  
  
  
  Video for Windows: YES
  
  
  
  DC1394: NO
  
  
  
  FFMPEG: YES (prebuilt binaries)
  
  
  
  avcodec: YES (ver 57.107.100)
  
  
  
  avformat: YES (ver 57.83.100)
  
  
  
  avutil: YES (ver 55.78.100)
  
  
  
  swscale: YES (ver 4.8.100)
  
  
  
  avresample: YES (ver 3.7.0)
  
  
  
  GStreamer:
  
  
  
  base: YES (ver 1.0)
  
  
  
  video: YES (ver 1.0)
  
  
  
  app: YES (ver 1.0)
  
  
  
  riff: YES (ver 1.0)
  
  
  
  pbutils: YES (ver 1.0)
  
  
  
  DirectShow: YES
  
  
  
  Media Foundation: YES
  
  
  
  
  
  Parallel framework: Concurrency
  
  
  
  
  
  Trace: YES (with Intel ITT)
  
  
  
  
  
  Other third-party libraries:
  
  
  
  Intel IPP: 2017.0.3 [2017.0.3]
  
  
  
  at: E:/OpenCV/3.4.3/build-cuda92-gstreamer/3rdparty/ippicv/ippicv_win
  
  
  
  Intel IPP IW: sources (2017.0.3)
  
  
  
  at: E:/OpenCV/3.4.3/build-cuda92-gstreamer/3rdparty/ippicv/ippiw_win
  
  
  
  Custom HAL: NO
  
  
  
  Protobuf: build (3.5.1)
  
  
  
  
  
  NVIDIA CUDA: YES (ver 9.2, CUFFT CUBLAS NVCUVID)
  
  
  
  NVIDIA GPU arch: 30 35 37 50 52 60 61 70
  
  
  
  NVIDIA PTX archs:
  
  
  
  
  
  OpenCL: YES (no extra features)
  
  
  
  Include path: E:/OpenCV/3.4.3/opencv-3.4.3/3rdparty/include/opencl/1.2
  
  
  
  Link libraries: Dynamic load
  
  
  
  
  
  Python (for build): C:/ProgramData/Miniconda3/python.exe
  
  
  
  
  
  Java:
  
  
  
  ant: C:/NVPACK/apache-ant-1.8.2/bin/ant.bat (ver 1.8.2)
  
  
  
  JNI: C:/NVPACK/jdk1.8.0_77/include C:/NVPACK/jdk1.8.0_77/include/win32 C:/NVPACK/jdk1.8.0_77/include
  
  
  
  Java wrappers: YES
  
  
  
  Java tests: YES
  
  
  
  
  
  Matlab: NO
  
  
  
  
  
  Install to: E:/OpenCV/3.4.3/build/install
  
  
  
  -----------------------------------------------------------------
  
  
  
  
  
  Configuring done
  
  </build>