Simulation Upload Update

server/transcoder.go

@@ -0,0 +1,46 @@
+package main
+
+import (
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+)
+
+func transcodeIfNeeded(simDir, filename string) string {
+	ext := strings.ToLower(filepath.Ext(filename))
+	if ext != ".avi" {
+		return filename
+	}
+
+	baseName := strings.TrimSuffix(filename, filepath.Ext(filename))
+	mp4Filename := baseName + ".mp4"
+	aviPath := filepath.Join(simDir, filename)
+	mp4Path := filepath.Join(simDir, mp4Filename)
+
+	// If the file was already transcoded prior, just remove the stale .avi and return .mp4
+	if _, err := os.Stat(mp4Path); err == nil {
+		os.Remove(aviPath)
+		return mp4Filename
+	}
+
+	log.Printf("Attempting GPU Transcoding (h264_nvenc) %s to %s...\n", aviPath, mp4Path)
+	cmdGPU := exec.Command("ffmpeg", "-y", "-i", aviPath, "-c:v", "h264_nvenc", "-pix_fmt", "yuv420p", "-movflags", "+faststart", mp4Path)
+	
+	if err := cmdGPU.Run(); err == nil {
+		os.Remove(aviPath)
+		return mp4Filename
+	}
+
+	log.Printf("GPU transcoding failed/unavailable, falling back to CPU (libx264) for %s...\n", aviPath)
+	cmdCPU := exec.Command("ffmpeg", "-y", "-i", aviPath, "-c:v", "libx264", "-pix_fmt", "yuv420p", "-movflags", "+faststart", mp4Path)
+	
+	if err := cmdCPU.Run(); err == nil {
+		os.Remove(aviPath)
+		return mp4Filename
+	} else {
+		log.Println("Failed to transcode (both GPU and CPU):", err)
+		return filename
+	}
+}