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• Convert GIF to MP4 with ffmpeg with palette color

  28 mars 2019, par NAG

  Palettegen is ok :

  ffmpeg()
  
  .input('temp/' + input.hash)
  
  .outputOptions(["-vf fps=15,scale=320:-1:flags=lanczos,palettegen"])
  
  .output('temp/palette.png')

  the conversion using the palette return a error :

  Error : Cannot find a matching stream for unlabeled input pad 1 on filter Parsed_paletteuse_0

  ffmpeg()
  
  .input('color=' + input.bg)
  
  .inputFormat('lavfi')
  
  .input('temp/' + input.hash)
  
  .inputFormat('gif')
  
  .input('temp/palette.png')
  
  .outputOptions('-lavfi paletteuse')
  
  .complexFilter(["[0][1]scale2ref[bg][gif]", "[bg]setsar=1[bg]", "[bg][gif]overlay=shortest=1[o]", "[o]scale=trunc(iw/2)*2:trunc(ih/2)*2"])
  
  .outputOptions(['-pix_fmt yuv420p', '-movflags frag_keyframe+empty_moov', '-movflags +faststart', '-crf 5'])
  
  .toFormat('mp4')
  
  .output('temp/final-' + input.hash)

  ffmpeg final command :

  ffmpeg -f lavfi -i color=ffffff -f gif -i temp/cf81f99083462f693406e8fd03ca7009 -i temp/palette.png -y -filter_complex [0][1]scale2ref[bg][gif];[bg]setsar=1[bg];[bg][gif]overlay=shortest=1[o];[o]scale=trunc(iw/2)*2:trunc(ih/2)*2 -lavfi paletteuse -pix_fmt yuv420p -movflags frag_keyframe+empty_moov -movflags +faststart -crf 5 -f mp4 temp/final-cf81f99083462f693406e8fd03ca7009

• Introducing Matomo SEO Web Vitals

  13 septembre 2021, par Ben Erskine — About, Analytics Tips, Plugins

  SEO Web Vitals track your critical website performance metrics and are a core element of SEO best practice. 

  Start using Matomo SEO Web Vitals to monitor your website performance, optimise your visitor experience, improve your search result rankings, and see how your site compares to your competitors.

  

  What are SEO Web Vitals ?

  Web Vitals are made up of a number of important metrics, such as your website’s page speed and loading performance, these metrics all play an important role in search engine optimisation. 

  The more technical terms for these metrics are Page Speed Score, First Contentful Paint (FCP), Final Input Delay (FID), Last Contentful Paint (LCP) and Cumulative Layout Shift (CLS).

  Why should you use SEO Web Vitals ?

  SEO Web Vitals are being used more and more by search engines such as Google to rank websites so they help ensure a great page experience for users who arrive via links from their search results. 

  By monitoring your SEO Web Vitals you can see how good or bad a single page performs and then prioritise the optimisation of strategically important pages to help improve the ranking position within search engine results.

  For ease of use you can receive regular reports in your email inbox and you can configure custom alerts to automatically notify you when a page score changes significantly. This saves time by not having to check page performance scores manually while ensuring you will be notified should there be any important change that needs to be actioned.

  You should use SEO Web Vitals to understand how your site performance is impacting your overall visitor experience.

  Four key benefits of using SEO Web Vitals :

  Improve your search result rankings

  • SEO Web Vitals are a core element of SEO best practice and directly impact your search rankings.
  • Pages that load quickly and are more stable deliver a better user experience, so they’re ranked higher by search engines.

  Optimise your website visitor experience

  • Know how quickly pages on your website load to ensure you deliver an optimal visitor experience.
  • Identify page stability issues and implement the changes needed to enhance your visitor experience.

  Automate your website performance monitoring

  • Have peace of mind knowing if your metrics decrease, you can find and fix the root cause quickly.
  • Configure performance alerts and get automated reports sent to you.

  Incorporate website performance into your competitor analysis

  • These performance metrics are essentially open for anyone to inspect, so you can measure and benchmark your site against competitors. 

  How can I improve my SEO Web Vitals ?

  There are so many ways to improve these performance metrics, here are five of the common contributing factors.

  1. Your page speed score is a weighted average of your other performance metrics, so focus on improving the underlying metrics that contribute to this score.
  2. Ensure you use a high quality web host with an appropriate plan for your level of traffic to help improve your FCP time.
  3. Try removing large elements that aren’t required on your page to improve your LCP time.
  4. Optimise against Total Blocking Time to Improve your FID score.
  5. Consider using a Layout Shift Debugger to improve Your CLS Score

  Guide to Matomo SEO Web Vitals

  For more information and to learn how to configure SEO Web Vitals in Matomo, check out our full guide to SEO Web Vitals.

  You will learn :

  • What’s required to measure your SEO Web Vitals
  • How to configure SEO Web Vitals
  • How to analyse your SEO Web Vitals
  • How to understanding SEO Web Vitals metrics
  • How to analyse your page’s SEO Web Vitals over time
  • How to improve your SEO Web Vitals
  • How to monitor changes in your scores with custom alerts

  Need more resources ?

  Matomo Plugin SEO Web Vitals

  Matomo SEO Web Vitals FAQs

• Recording voice using HTML5 and processing it with ffmpeg

  22 mars 2015, par user3789242

  I need to use ffmpeg in my javascript/HTML5 project which allows the user to select the format he wants the audio to open with.I don’t know anything about ffmpeg and I’ve been doing lots of research I don’t know how to use it in my project. I found an example https://github.com/sopel39/audioconverter.js but the problem how can I install the ffmpeg.js which is 8 mg to m project. please if someone can help me I’ll be very thankfull
  here is my full code :

  the javascript page :

  // variables
  
  var leftchannel = [];
  
  var rightchannel = [];
  
  var recorder = null;
  
  var recording = false;
  
  var recordingLength = 0;
  
  var volume = null;
  
  var audioInput = null;
  
  var sampleRate = 44100;
  
  var audioContext = null;
  
  var context = null;
  
  var outputString;
  
  
  
  
  
  
  
  if (!navigator.getUserMedia)
  
  navigator.getUserMedia = navigator.getUserMedia ||
  
                           navigator.webkitGetUserMedia ||
  
                           navigator.mozGetUserMedia || 
  
                           navigator.msGetUserMedia;
  
  
  
  if (navigator.getUserMedia){
  
  navigator.getUserMedia({audio:true}, success, function(e) {
  
  alert('Error capturing audio.');
  
  });
  
  } else alert('getUserMedia not supported in this browser.');
  
  
  
  
  
  
  
  function getVal(value)
  
    {
  
  
  
  // if R is pressed, we start recording
  
  if ( value == "record"){
  
      recording = true;
  
      // reset the buffers for the new recording
  
      leftchannel.length = rightchannel.length = 0;
  
      recordingLength = 0;
  
      document.getElementById('output').innerHTML="Recording now...";
  
  
  
   // if S is pressed, we stop the recording and package the WAV file
  
   } else if ( value == "stop" ){
  
  
  
      // we stop recording
  
      recording = false;
  
      document.getElementById('output').innerHTML="Building wav file...";
  
  
  
      // we flat the left and right channels down
  
      var leftBuffer = mergeBuffers ( leftchannel, recordingLength );
  
      var rightBuffer = mergeBuffers ( rightchannel, recordingLength );
  
      // we interleave both channels together
  
      var interleaved = interleave ( leftBuffer, rightBuffer );
  
  
  
  
  
  
  
      var buffer = new ArrayBuffer(44 + interleaved.length * 2);
  
      var view = new DataView(buffer);
  
  
  
      // RIFF chunk descriptor
  
      writeUTFBytes(view, 0, 'RIFF');
  
      view.setUint32(4, 44 + interleaved.length * 2, true);
  
      writeUTFBytes(view, 8, 'WAVE');
  
      // FMT sub-chunk
  
      writeUTFBytes(view, 12, 'fmt ');
  
      view.setUint32(16, 16, true);
  
      view.setUint16(20, 1, true);
  
      // stereo (2 channels)
  
      view.setUint16(22, 2, true);
  
      view.setUint32(24, sampleRate, true);
  
      view.setUint32(28, sampleRate * 4, true);
  
      view.setUint16(32, 4, true);
  
      view.setUint16(34, 16, true);
  
      // data sub-chunk
  
      writeUTFBytes(view, 36, 'data');
  
      view.setUint32(40, interleaved.length * 2, true);
  
  
  
  
  
      var lng = interleaved.length;
  
      var index = 44;
  
      var volume = 1;
  
      for (var i = 0; i < lng; i++){
  
          view.setInt16(index, interleaved[i] * (0x7FFF * volume), true);
  
          index += 2;
  
      }
  
  
  
      var blob = new Blob ( [ view ], { type : 'audio/wav' } );
  
  
  
      // let's save it locally
  
  
  
      document.getElementById('output').innerHTML='Handing off the file now...';
  
      var url = (window.URL || window.webkitURL).createObjectURL(blob);
  
  
  
      var li = document.createElement('li');
  
      var au = document.createElement('audio');
  
      var hf = document.createElement('a');
  
  
  
      au.controls = true;
  
      au.src = url;
  
      hf.href = url;
  
      hf.download = 'audio_recording_' + new Date().getTime() + '.wav';
  
      hf.innerHTML = hf.download;
  
      li.appendChild(au);
  
      li.appendChild(hf);
  
      recordingList.appendChild(li);
  
  
  
  }
  
  }
  
  
  
  
  
  function success(e){
  
  
  
  audioContext = window.AudioContext || window.webkitAudioContext;
  
  context = new audioContext();
  
  
  
  
  
  volume = context.createGain();
  
  
  
  // creates an audio node from the microphone incoming stream(source)
  
  source = context.createMediaStreamSource(e);
  
  
  
  // connect the stream(source) to the gain node
  
  source.connect(volume);
  
  
  
  var bufferSize = 2048;
  
  
  
  recorder = context.createScriptProcessor(bufferSize, 2, 2);
  
  
  
  //node for the visualizer
  
  analyser = context.createAnalyser();
  
  analyser.smoothingTimeConstant = 0.3;
  
  analyser.fftSize = 512;
  
  
  
  splitter = context.createChannelSplitter();
  
  //when recording happens
  
  recorder.onaudioprocess = function(e){
  
  
  
      if (!recording) return;
  
      var left = e.inputBuffer.getChannelData (0);
  
      var right = e.inputBuffer.getChannelData (1);
  
  
  
      leftchannel.push (new Float32Array (left));
  
      rightchannel.push (new Float32Array (right));
  
      recordingLength += bufferSize;
  
  
  
      // get the average for the first channel
  
      var array =  new Uint8Array(analyser.frequencyBinCount);
  
      analyser.getByteFrequencyData(array);
  
  
  
      var c=document.getElementById("myCanvas");
  
      var ctx = c.getContext("2d");
  
      // clear the current state
  
      ctx.clearRect(0, 0, 1000, 325);
  
      var gradient = ctx.createLinearGradient(0,0,0,300);
  
      gradient.addColorStop(1,'#000000');
  
      gradient.addColorStop(0.75,'#ff0000');
  
      gradient.addColorStop(0.25,'#ffff00');
  
      gradient.addColorStop(0,'#ffffff');
  
      // set the fill style
  
      ctx.fillStyle=gradient;
  
      drawSpectrum(array);
  
      function drawSpectrum(array) {
  
          for ( var i = 0; i < (array.length); i++ ){
  
                  var value = array[i];
  
                  ctx.fillRect(i*5,325-value,3,325);
  
              } 
  
  
  
      }
  
  }
  
  
  
  function getAverageVolume(array) {
  
      var values = 0;
  
      var average;
  
  
  
      var length = array.length;
  
  
  
      // get all the frequency amplitudes
  
      for (var i = 0; i < length; i++) {
  
          values += array[i];
  
      }
  
  
  
      average = values / length;
  
      return average;
  
  }
  
  
  
      // we connect the recorder(node to destination(speakers))
  
      volume.connect(splitter);
  
      splitter.connect(analyser, 0, 0);
  
  
  
      analyser.connect(recorder);
  
      recorder.connect(context.destination);
  
  
  
  }
  
  
  
  
  
  
  
  
  
  function mergeBuffers(channelBuffer, recordingLength){
  
  var result = new Float32Array(recordingLength);
  
  var offset = 0;
  
  var lng = channelBuffer.length;
  
  for (var i = 0; i < lng; i++){
  
  var buffer = channelBuffer[i];
  
  result.set(buffer, offset);
  
  offset += buffer.length;
  
  }
  
      return result;
  
     }
  
  
  
  function interleave(leftChannel, rightChannel){
  
  var length = leftChannel.length + rightChannel.length;
  
  var result = new Float32Array(length);
  
  
  
  var inputIndex = 0;
  
  
  
  for (var index = 0; index < length; ){
  
   result[index++] = leftChannel[inputIndex];
  
   result[index++] = rightChannel[inputIndex];
  
   inputIndex++;
  
  }
  
  return result;
  
  }
  
  
  
  
  
  function writeUTFBytes(view, offset, string){ 
  
  var lng = string.length;
  
  for (var i = 0; i < lng; i++){
  
  
  
  view.setUint8(offset + i, string.charCodeAt(i));
  
  }
  
  }

  and here is the html code :

      
  
      
  
      
  
      <code class="echappe-js">&lt;script src=&quot;http://stackoverflow.com/feeds/tag/js/functions.js&quot;&gt;&lt;/script&gt;