From 7ced157f52f12abd2492e225be363bd36d684d65 Mon Sep 17 00:00:00 2001
From: N00MKRAD <me@nmkd.de>
Date: Wed, 23 Dec 2020 18:21:31 +0100
Subject: [PATCH] Fixed Audio support for non-MP4 formats

---
 Code/AudioVideo/FFmpegCommands.cs | 25 ++++++++++++++-----------
 Code/AudioVideo/FFmpegUtils.cs    | 19 +++++++++++++++++++
 Code/Main/Interpolate.cs          |  2 +-
 3 files changed, 34 insertions(+), 12 deletions(-)

diff --git a/Code/AudioVideo/FFmpegCommands.cs b/Code/AudioVideo/FFmpegCommands.cs
index b41e36f..05cb78a 100644
--- a/Code/AudioVideo/FFmpegCommands.cs
+++ b/Code/AudioVideo/FFmpegCommands.cs
@@ -1,4 +1,5 @@
-using Flowframes.Data;
+using Flowframes.AudioVideo;
+using Flowframes.Data;
 using Flowframes.IO;
 using Flowframes.Main;
 using System;
@@ -204,9 +205,9 @@ namespace Flowframes
         public static async Task ExtractAudio(string inputFile, string outFile)    // https://stackoverflow.com/a/27413824/14274419
         {
             Logger.Log($"[FFCmds] Extracting audio from {inputFile} to {outFile}", true);
-            string ext = GetAudioExt(inputFile);
-            outFile = Path.ChangeExtension(outFile, ext);
-            string args = $" -loglevel panic -i {inputFile.Wrap()} -vn -acodec copy {outFile.Wrap()}";
+            //string ext = GetAudioExt(inputFile);
+            outFile = Path.ChangeExtension(outFile, ".ogg");
+            string args = $" -loglevel panic -i {inputFile.Wrap()} -vn -acodec libopus -b:a 320k {outFile.Wrap()}";
             await AvProcess.RunFfmpeg(args, AvProcess.LogMode.Hidden);
             if (AvProcess.lastOutputFfmpeg.ToLower().Contains("error") && File.Exists(outFile))    // If broken file was written
                 File.Delete(outFile);
@@ -227,13 +228,15 @@ namespace Flowframes
         public static async Task MergeAudio(string inputFile, string audioPath, int looptimes = -1)    // https://superuser.com/a/277667
         {
             Logger.Log($"[FFCmds] Merging audio from {audioPath} into {inputFile}", true);
-            string tempPath = inputFile + "-temp.mp4";
-            if (Path.GetExtension(audioPath) == ".wav")
-            {
-                Logger.Log("Using MKV instead of MP4 to enable support for raw audio.");
-                tempPath = Path.ChangeExtension(tempPath, "mkv");
-            }
-            string args = $" -i {inputFile.Wrap()} -stream_loop {looptimes} -i {audioPath.Wrap()} -shortest -c copy {tempPath.Wrap()}";
+            string tempPath = inputFile + "-temp" + Path.GetExtension(inputFile);
+            // if (Path.GetExtension(audioPath) == ".wav")
+            // {
+            //     Logger.Log("Using MKV instead of MP4 to enable support for raw audio.");
+            //     tempPath = Path.ChangeExtension(tempPath, "mkv");
+            // }
+            string aCodec = Utils.GetAudioEnc(Utils.GetCodec(Interpolate.current.outMode));
+            int aKbits = Utils.GetAudioBitrate(aCodec);
+            string args = $" -i {inputFile.Wrap()} -stream_loop {looptimes} -i {audioPath.Wrap()} -shortest -c:v copy -c:a {aCodec} -b:a {aKbits}k {tempPath.Wrap()}";
             await AvProcess.RunFfmpeg(args, AvProcess.LogMode.Hidden);
             if (AvProcess.lastOutputFfmpeg.Contains("Invalid data"))
             {
diff --git a/Code/AudioVideo/FFmpegUtils.cs b/Code/AudioVideo/FFmpegUtils.cs
index 4107e68..96bed09 100644
--- a/Code/AudioVideo/FFmpegUtils.cs
+++ b/Code/AudioVideo/FFmpegUtils.cs
@@ -60,6 +60,25 @@ namespace Flowframes.AudioVideo
             return args;
         }
 
+        public static string GetAudioEnc(Codec codec)
+        {
+            switch (codec)
+            {
+                case Codec.VP9: return "libopus";
+            }
+            return "aac";
+        }
+
+        public static int GetAudioBitrate (string codec)
+        {
+            if (codec.Trim().ToLower() == "aac")
+                return 128;
+            if (codec.Trim().ToLower().Contains("opus"))
+                return 112;
+
+            return 160;
+        }
+
         public static string GetExt(Interpolate.OutMode outMode, bool dot = true)
         {
             string ext = dot ? "." : "";
diff --git a/Code/Main/Interpolate.cs b/Code/Main/Interpolate.cs
index 1b2e651..52a3535 100644
--- a/Code/Main/Interpolate.cs
+++ b/Code/Main/Interpolate.cs
@@ -87,7 +87,7 @@ namespace Flowframes
 
             if (extractAudio)
             {
-                string audioFile = Path.Combine(current.tempFolder, "audio.m4a");
+                string audioFile = Path.Combine(current.tempFolder, "audio");
                 if (audioFile != null && !File.Exists(audioFile))
                     await FFmpegCommands.ExtractAudio(inPath, audioFile);
             }