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• VP8 Codec SDK "Aylesbury" Release

  28 octobre 2010, par noreply@blogger.com (John Luther)

  Today we’re making available "Aylesbury," our first named release of libvpx, the VP8 codec SDK. VP8 is the video codec used in WebM. Note that the VP8 specification has not changed, only the SDK.

  What’s an Aylesbury ? It’s a breed of duck. We like ducks, so we plan to use duck-related names for each major libvpx release, in alphabetical order. Our goal is to have one named release of libvpx per calendar quarter, each with a theme.

  You can download the Aylesbury libvpx release from our Downloads page or check it out of our Git repository and build it yourself. In the coming days Aylesbury will be integrated into all of the WebM project components (DirectShow filters, QuickTime plugins, etc.). We encourage anyone using our components to upgrade to the Aylesbury releases.

  For Aylesbury the theme was faster decoder, better encoder. We used our May 19, 2010 launch release of libvpx as the benchmark. We’re very happy with the results (see graphs below) :
  

  • 20-40% (average 28%) improvement in libvpx decoder speed
  • Over 7% overall PSNR improvement (6.3% SSIM) in VP8 "best" quality encoding mode, and up to 60% improvement on very noisy, still or slow moving source video.

  

  
  

  

  
  

  

  
  

  The main improvements to the decoder are :
  

  • Single-core assembly "hot spot" optimizations, including improved vp8_sixtap_predict() and SSE2 loopfilter functions
  • Threading improvements for more efficient use of multiple processor cores
  • Improved memory handling and reduced footprint
  • Combining IDCT and reconstruction steps
  • SSSE3 usage in functions where appropriate

  On the encoder front, we concentrated on clips in the 30-45 dB range and saw the biggest gains in higher-quality source clips (greater that 38 dB), low to medium-motion clips, and clips with noisy source material. Many code contributions made this possible, but a few of the highlights were :
  

  • Adaptive width and strength alternate reference frame noise suppression filter with optional motion compensation.
  • Transform improvements (improved accuracy and reduction in round trip error)
  • Trellis-based quantized coefficient optimization
  • Two-pass rate control and quantizer changes
  • Rate distortion changes
  • Zero bin and rounding changes
  • Work on MB-level quality control and bit allocation

  We’re targeting Q1 2011 for the next named libvpx release, which we’re calling Bali. The theme for that release will be faster encoder. We are constantly working on improvements to video quality in the encoder, so after Aylesbury we won’t tie that work to specific named releases.

  WebM at Streaming Media West

  Members of the WebM project will discuss Aylesbury during a session at the Streaming Media West conference on November 3rd (session C203 : WebM Open Video Project Update). For more information, visit www.streamingmedia.com/west.

  John Luther is Product Manager of the WebM Project.

  

• why am i getting this error when using FFmpeg in a spring boot app on a mac intel device : SIGSEGV (0xb) at pc=0x000000013d71b0e0, pid=49777, tid=42755

  19 juillet 2024, par Godwill Christopher

  I am working with FFmpeg library in spring boot app to stream live recording from an ip camera via RSTP and save to S3 bucket but i am running into the error below.

  


  A fatal error has been detected by the Java Runtime Environment :

  


  SIGSEGV (0xb) at pc=0x000000013d71b0e0, pid=49777, tid=42755

  


  JRE version : OpenJDK Runtime Environment Corretto-19.0.2.7.1 (19.0.2+7) (build 19.0.2+7-FR)
Java VM : OpenJDK 64-Bit Server VM Corretto-19.0.2.7.1 (19.0.2+7-FR, mixed mode, sharing, tiered, compressed oops, compressed class ptrs, g1 gc, bsd-amd64)
Problematic frame :
C [libavutil.56.dylib+0xa0e0] av_strstart+0x10

  


  No core dump will be written. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again
An error report file with more information is saved as :
/Users/CODA/Desktop/videoSaleService/hs_err_pid49777.log

  


  If you would like to submit a bug report, please visit :
https://github.com/corretto/corretto-19/issues/
The crash happened outside the Java Virtual Machine in native code.
See problematic frame for where to report the bug.

  


  Process finished with exit code 134 (interrupted by signal 6:SIGABRT)

  


  public static void main(String[] args) {
    OkHttpClient client = new OkHttpClient();
    try (S3Client s3Client = S3Client.create()) {
        VideoService videoService = new VideoService(new VideoRepositoryImpl(),
                new S3Service(s3Client), new VideoExtractor(client), new ISApiClient());
        videoService.streamLiveVideoRSTP(System.out);
    } catch (IOException e) {
        log.error("Error occurred while streaming live video: {}", e.getMessage(), e);
    } catch (Exception e) {
        log.error("Unexpected error occurred: {}", e.getMessage(), e);
    }
}

public void streamLiveVideoRSTP(OutputStream outputStream) throws IOException {
    File tempFile = File.createTempFile("live_stream", ".mp4");

    try (InputStream inputStream = client.getLiveStreamingVideoRSTP();
         OutputStream fileOutputStream = new FileOutputStream(tempFile)) {
        byte[] buffer = new byte[4096];
        int bytesRead;
        while ((bytesRead = inputStream.read(buffer)) != -1) {
            outputStream.write(buffer, 0, bytesRead);
            fileOutputStream.write(buffer, 0, bytesRead);
        }
    } catch (Exception e) {
        log.error("Error occurred while streaming live video: {}", e.getMessage(), e);
        throw new IOException("Error occurred while streaming live video", e);
    }

    // Upload the captured video file to S3
    try {
        uploadStreamedVideoToS3(tempFile);
    } finally {
        if (tempFile.exists()) {
            if (!tempFile.delete()) {
                log.warn("Failed to delete temporary file: {}", tempFile.getAbsolutePath());
            }
        }
    }
}

private final BlockingQueue frameQueue = new ArrayBlockingQueue<>(10);

public ISApiClient() {
    new Thread(this::startGrabbingFrames).start();
}

public InputStream getLiveStreamingVideoRSTP() {
    return new InputStream() {
        private ByteArrayInputStream currentStream;

        @Override
        public int read() {
            if (currentStream == null || currentStream.available() == 0) {
                byte[] frame = frameQueue.poll();
                if (frame != null) {
                    currentStream = new ByteArrayInputStream(frame);
                } else {
                    return -1;
                }
            }
            return currentStream.read();
        }
    };
}

private void startGrabbingFrames() {
    try (FFmpegFrameGrabber frameGrabber = new FFmpegFrameGrabber(rtspUrl)) {
        frameGrabber.setOption("rtsp_transport", "tcp");
        frameGrabber.start();

        FFmpegFrameFilter frameFilter = new FFmpegFrameFilter("format=yuv420p",
                frameGrabber.getImageWidth(), frameGrabber.getImageHeight());
        frameFilter.setPixelFormat(frameGrabber.getPixelFormat());
        frameFilter.start();

        log.info("Started grabbing frames from RTSP stream.");

        while (true) {
            Frame frame = frameGrabber.grab();
            if (frame != null && frame.image != null) {
                log.info("Frame grabbed: width={} height={} timestamp={}",
                        frame.imageWidth, frame.imageHeight, frame.timestamp);
                frameFilter.push(frame);
                Frame filteredFrame = frameFilter.pull();

                if (filteredFrame != null && filteredFrame.image != null) {
                    log.info("Frame filtered: width={} height={} timestamp={}",
                            filteredFrame.imageWidth, filteredFrame.imageHeight, filteredFrame.timestamp);
                    byte[] imageBytes = convertFrameToBytes(filteredFrame);
                    if (imageBytes.length > 0) {
                        frameQueue.offer(imageBytes);
                        log.info("Frame added to queue, queue size={}", frameQueue.size());
                    }
                }
            }
        }
    } catch (IOException e) {
        log.error("Error grabbing frames: {}", e.getMessage(), e);
    }
}

private byte[] convertFrameToBytes(Frame frame) {
    if (frame == null || frame.image == null) {
        return new byte[0];
    }

    ByteBuffer byteBuffer = null;
    for (Object img : frame.image) {
        if (img instanceof ByteBuffer) {
            byteBuffer = (ByteBuffer) img;
            break;
        }
    }

    if (byteBuffer == null) {
        return new byte[0];
    }

    byte[] bytes = new byte[byteBuffer.remaining()];
    byteBuffer.get(bytes);
    return bytes;
}


  


• Generating test data – Introducing the Piwik Platform

  9 octobre 2014, par Thomas Steur — Development

  This is the next post of our blog series where we introduce the capabilities of the Piwik platform (our previous post was How to create a command). This time you’ll learn how to generate test data.

  Developers are developing on their local Piwik instance which usually does not contain useful data compared to a real Piwik installation in production (only a few test visits and a few tests users and websites). The ‘VisitorGenerator’ plugin lets you generate any number of visits, websites, users, goals and more. The generator makes sure there will be data for each report so you can easily test anything.

  Getting started

  In this series of posts, we assume that you have already installed Piwik. If not, visit the Piwik Developer Zone where you’ll find the Installation guide for developers.

  Installing the VisitorGenerator plugin

  The easiest way to install the plugin is by using the Marketplace in Piwik itself. It is accessible via Settings => Marketplace => Get new functionality. There you’ll find the plugin “VisitorGenerator” which you can install and activate in one click.

  If your Piwik instance is not connected to the internet you can download the plugin from the VisitorGenerator page on the Marketplace. Afterwards you can install the plugin by going to Settings => Marketplace => Uploading a plugin and uploading the previously downloaded ZIP file.

  If you have already installed the plugin make sure it is activated by going to Settings => Plugins.

  Generating websites

  After you have installed the plugin you can add as many websites as you need. This is useful for instance when you want to test something that affects many websites such as the ‘All Websites’ dashboard or the Websites manager. To generate any number of websites use the following command :

  ./console visitorgenerator:generate-website --limit=10

  This will generate 10 websites. If you need more websites simply specify a higher limit. In case you are wondering the names and URLs of the websites are randomly generated by the Faker PHP library.

  Generating goals

  In case you want to test anything related to Goals you should execute the following command :

  ./console visitorgenerator:generate-goals --idsite=1

  This will generate a few goals for the specified site. The generated goals are defined in a way to make sure there will be conversions when generating the visits in the next step.

  Generating visits

  To generate visits there are two possibilities. Either via the Piwik UI by going to Settings => Visitor Generator or by using the command line. The UI is a bit limited in generating visits so we recommend to use the command line. There you can generate visits as follows :

  ./console visitorgenerator:generate-visits --idsite=1

  This will generate many different visits for the current day. Don’t worry if it takes a while, it will insert quite a few visits by default.

  In case you want to generate visits for multiple days in the past as well you can specify the --days option.

  ./console visitorgenerator:generate-visits --idsite=1 --days=5

  Providing your own logs

  Half of the generated visits are randomly generated and half of the visits are based on real logs to make sure there is data for each report. If you want to generate visits based on your own logs for a more realistic testing just place your log files in the plugins/VisitorGenerator/data folder and make sure the file name ends with .log. You can find a few examples in the VisitorGenerator data folder.

  To generate visits based only on real log files then use the --no-fake option.

  ./console visitorgenerator:generate-visits --idsite=1 --no-fake

  All generated visits will come from the logs and no random visits nor random fake data will be used.

  Advanced features

  We are regularly adding new commands, tools and runtime checks to make your life as a developer easier. For instance you can also generate users and annotations. In the future we want to extend the plugin to create visits in the background to make sure there will be constantly new actions in the real time report.

  Are you missing any kind of generator or any other feature to make your life as a developer easier ? Let us know by email, we are listening !

  Would you like to know more about the Piwik platform ? Go to our Piwik Developer Zone where you’ll find guides and references on how to develop plugin and themes.