Fix issue with waveform rendering

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/send/WaveFormSanitizer.kt

@@ -80,7 +80,7 @@ internal class WaveFormSanitizer @Inject constructor() {
             positiveList
         }
 
-        Timber.d("Sanitize from ${waveForm.size} items to ${finalList.size} items")
+        Timber.d("Sanitize from ${waveForm.size} items to ${finalList.size} items. Max value was $max")
         return finalList
     }
 }

vector/src/main/java/im/vector/app/features/home/room/detail/timeline/factory/MessageItemFactory.kt

@@ -257,7 +257,7 @@ class MessageItemFactory @Inject constructor(
         return MessageVoiceItem_()
                 .attributes(attributes)
                 .duration(messageContent.audioWaveformInfo?.duration ?: 0)
-                .waveform(messageContent.audioWaveformInfo?.waveform ?: emptyList())
+                .waveform(messageContent.audioWaveformInfo?.waveform?.toFft().orEmpty())
                 .playbackControlButtonClickListener(playbackControlButtonClickListener)
                 .voiceMessagePlaybackTracker(voiceMessagePlaybackTracker)
                 .izLocalFile(localFilesHelper.isLocalFile(fileUrl))
@@ -622,6 +622,13 @@ class MessageItemFactory @Inject constructor(
                 .highlighted(highlight)
     }
 
+    private fun List<Int>?.toFft(): List<Int>? {
+        return this?.map {
+            // Value comes from AudioRecordView.maxReportableAmp, and 1024 is the max value in the Matrix spec
+            it * 22760 / 1024
+        }
+    }
+
     companion object {
         private const val MAX_NUMBER_OF_EMOJI_FOR_BIG_FONT = 5
     }