Merge branch 'audio-waveforms' into 'dev'

Audio waveforms

See merge request keanuapp/keanuapp-weblite!321

src/components/messages/AudioPlayer.vue

@@ -6,15 +6,22 @@
     <div class="play-time">
       {{ currentTime }} / {{ totalTime }}
     </div>
+    <div style="position:relative;flex: 1 1 100%">
     <v-slider @change="seeked" :disabled="!info.url" color="currentColor" track-color="#cccccc" class="play-progress" :value="info.playPercent" min="0"
       max="100" />
+      <div style="position:absolute;left:18px;right:18px;top:0;bottom:0;height:100%">
+      <AudioWaveformView :event="event" style="width:100%;height:100%" />
+      </div>
+    </div>
   </div>
 </template>
 
 <script>
 import util from "../../plugins/utils";
+import AudioWaveformView from "./AudioWaveformView.vue";
 
 export default {
+  components: { AudioWaveformView },
   props: {
     event: {
       type: Object,

src/components/messages/AudioWaveformView.vue

@@ -0,0 +1,45 @@
+<template>
+    <div v-html="content" class="waveform">
+    </div>
+</template>
+
+<script>
+
+export default {
+    props: {
+        event: {
+            type: Object,
+            default: function () {
+                return null;
+            },
+        },
+    },
+    computed: {
+        content() {
+            return this.$sanitize(
+                this.event ? this.event.getContent().formatted_body : "",
+                {
+                    allowedTags: ["svg", "path"],
+                    allowedAttributes: {
+                        'svg': ["viewbox", "fill", "preserveaspectratio", "xmlns"],
+                        'path': ["d", "style"]
+                    }
+                }
+            );
+        }
+    },
+};
+</script>
+
+<style lang="scss">
+@import "@/assets/css/chat.scss";
+
+.waveform svg {
+    width: 100%;
+    height: 100%;
+
+    path {
+        stroke: black !important;
+    }
+}
+</style>

src/plugins/utils.js

@@ -424,6 +424,9 @@ class Util {
                     promise
                         .then((response) => {
                             messageContent.url = response.content_uri;
+                            return (msgtype == 'm.audio' ? this.generateWaveform(fileContents, messageContent) : true);
+                        })
+                        .then(() => {
                             return this.sendMessage(matrixClient, roomId, "m.room.message", messageContent)
                         })
                         .then(result => {
@@ -478,6 +481,9 @@ class Util {
                             return reject(response.error);
                         }
                         encryptedFile.url = response.content_uri;
+                        return (msgtype == 'm.audio' ? this.generateWaveform(fileContents, messageContent) : true);
+                    })
+                    .then(() => {
                         return this.sendMessage(matrixClient, roomId, "m.room.message", messageContent)
                     })
                     .then(result => {
@@ -495,6 +501,51 @@ class Util {
         return uploadPromise;
     }
 
+    generateWaveform(data, messageContent) {
+        if (!(window.AudioContext || window.webkitAudioContext)) {
+            return; // No support
+        }
+        const audioCtx = new (window.AudioContext || window.webkitAudioContext)();
+        if (audioCtx) {
+            return audioCtx.decodeAudioData(data)
+                .then((audioBuffer) => {
+                    const rawData = audioBuffer.getChannelData(0); // TODO - currently using only 1 channel
+                    const samples = 1000; // Number of samples
+                    const blockSize = Math.floor(rawData.length / samples);
+                    let filteredData = [];
+                    for (let i = 0; i < samples; i++) {
+                      let blockStart = blockSize * i; // the location of the first sample in the block
+                      let sum = 0;
+                      for (let j = 0; j < blockSize; j++) {
+                        sum = sum + Math.abs(rawData[blockStart + j]) // find the sum of all the samples in the block
+                      }
+                      filteredData.push(sum / blockSize); // divide the sum by the block size to get the average
+                    }
+
+                    // Normalize
+                    const multiplier = Math.pow(Math.max(...filteredData), -1);
+                    filteredData = filteredData.map(n => n * multiplier);
+
+                    // Integerize
+                    filteredData = filteredData.map(n => parseInt((n * 255).toFixed()));
+                    
+
+                    // Generate SVG of waveform
+                    let svg = `<svg viewBox="0 0 ${samples} 255" fill="none" preserveAspectRatio="none" xmlns="http://www.w3.org/2000/svg">`;
+                    svg += `<path d="`;
+                    filteredData.forEach((d, i) => {
+                        const delta = d / 2; 
+                        svg += `M${i} ${128 - delta}V${128 + delta}`;
+                    });
+                    svg += `" style="fill:none;stroke:green;stroke-width:1" />`;
+                    svg += "</svg>";
+
+                    messageContent.format = "org.matrix.custom.html";
+                    messageContent.formatted_body = svg;
+                })
+        }
+    }
+
     /**
      * Return what "mode" to use for the given room.
      *