From 26d6844bc6422869e4277043e46afa672014d8ec Mon Sep 17 00:00:00 2001
From: tildearrow <me@tildearrow.org>
Date: Thu, 6 Nov 2025 01:13:12 -0500
Subject: [PATCH] add output format command line option

also auto-detect format based on extension
---
 src/main.cpp | 57 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 57 insertions(+)

diff --git a/src/main.cpp b/src/main.cpp
index b39daa9db..898338fa5 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -117,6 +117,8 @@ bool infoMode=false;
 
 bool noReportError=false;
 
+bool hasOutFormat=false;
+
 std::vector<TAParam> params;
 
 #ifdef HAVE_LOCALE
@@ -451,6 +453,36 @@ TAParamResult pOutMode(String val) {
   return TA_PARAM_SUCCESS;
 }
 
+TAParamResult pOutFormat(String val) {
+  if (hasOutFormat) {
+    logE("the output format is already set.");
+    return TA_PARAM_ERROR;
+  }
+  hasOutFormat=true;
+  if (val=="u8") {
+    exportOptions.format=DIV_EXPORT_FORMAT_WAV;
+    exportOptions.wavFormat=DIV_EXPORT_WAV_U8;
+  } else if (val=="s16") {
+    exportOptions.format=DIV_EXPORT_FORMAT_WAV;
+    exportOptions.wavFormat=DIV_EXPORT_WAV_S16;
+  } else if (val=="f32") {
+    exportOptions.format=DIV_EXPORT_FORMAT_WAV;
+    exportOptions.wavFormat=DIV_EXPORT_WAV_F32;
+  } else if (val=="opus") {
+    exportOptions.format=DIV_EXPORT_FORMAT_OPUS;
+  } else if (val=="flac") {
+    exportOptions.format=DIV_EXPORT_FORMAT_FLAC;
+  } else if (val=="vorbis") {
+    exportOptions.format=DIV_EXPORT_FORMAT_VORBIS;
+  } else if (val=="mp3") {
+    exportOptions.format=DIV_EXPORT_FORMAT_MPEG_L3;
+  } else {
+    logE("invalid value for outformat! valid values are: u8, s16, f32, opus, flac, vorbis and mp3.");
+    return TA_PARAM_ERROR;
+  }
+  return TA_PARAM_SUCCESS;
+}
+
 TAParamResult pBenchmark(String val) {
   if (val=="render") {
     benchMode=1;
@@ -467,6 +499,30 @@ TAParamResult pBenchmark(String val) {
 TAParamResult pOutput(String val) {
   outName=val;
   e.setAudio(DIV_AUDIO_DUMMY);
+
+  // detect output format
+  if (!hasOutFormat) {
+    size_t extPos=outName.rfind('.');
+    if (extPos!=String::npos) {
+      String lowerCase=outName.substr(extPos);
+      for (char& i: lowerCase) {
+        if (i>='A' && i<='Z') i+='a'-'A';
+      }
+
+      if (lowerCase==".wav") {
+        exportOptions.format=DIV_EXPORT_FORMAT_WAV;
+      } else if (lowerCase==".ogg") {
+        // not defaulting to Vorbis in order to encourage Opus usage
+        exportOptions.format=DIV_EXPORT_FORMAT_OPUS;
+      } else if (lowerCase==".flac") {
+        exportOptions.format=DIV_EXPORT_FORMAT_FLAC;
+      } else if (lowerCase==".opus") {
+        exportOptions.format=DIV_EXPORT_FORMAT_OPUS;
+      } else if (lowerCase==".mp3") {
+        exportOptions.format=DIV_EXPORT_FORMAT_MPEG_L3;
+      }
+    }
+  }
   return TA_PARAM_SUCCESS;
 }
 
@@ -520,6 +576,7 @@ void initParams() {
 
   params.push_back(TAParam("a","audio",true,pAudio,"jack|sdl|portaudio|pipe","set audio engine (SDL by default)"));
   params.push_back(TAParam("o","output",true,pOutput,"<filename>","output audio to file"));
+  params.push_back(TAParam("f","outformat",true,pOutFormat,"u8|s16|f32|opus|flac|vorbis|mp3","set audio output format"));
   params.push_back(TAParam("O","vgmout",true,pVGMOut,"<filename>","output .vgm data"));
   params.push_back(TAParam("D","direct",false,pDirect,"","set VGM export direct stream mode"));
   params.push_back(TAParam("C","cmdout",true,pCmdOut,"<filename>","output command stream"));