Update renderer.py

renderer.py

@@ -1,3 +1,4 @@
+import os
 import subprocess
 
 
@@ -5,14 +6,45 @@ def render_final_video(
     background,
     audio,
     subtitles,
-    output
+    output,
+    crf=23,
+    preset="medium"
 ):
 
+    if not os.path.exists(background):
+        raise FileNotFoundError(
+            f"Background not found: {background}"
+        )
+
+    if not os.path.exists(audio):
+        raise FileNotFoundError(
+            f"Audio not found: {audio}"
+        )
+
+    if not os.path.exists(subtitles):
+        raise FileNotFoundError(
+            f"Subtitle not found: {subtitles}"
+        )
+
+    print("=" * 50)
+    print("FINAL RENDER")
+    print("=" * 50)
+
+    print("Background :", background)
+    print("Audio      :", audio)
+    print("Subtitle   :", subtitles)
+    print("Output     :", output)
+
+    vf_filter = (
+        f"ass={subtitles}:fontsdir=fonts"
+    )
+
     cmd = [
         "ffmpeg",
 
         "-y",
 
+        # loop background
         "-stream_loop",
         "-1",
 
@@ -23,7 +55,7 @@ def render_final_video(
         audio,
 
         "-vf",
-        f"ass={subtitles}:fontsdir=fonts",
+        vf_filter,
 
         "-map",
         "0:v",
@@ -35,10 +67,16 @@ def render_final_video(
         "libx264",
 
         "-preset",
-        "medium",
+        preset,
 
         "-crf",
-        "23",
+        str(crf),
+
+        "-pix_fmt",
+        "yuv420p",
+
+        "-movflags",
+        "+faststart",
 
         "-c:a",
         "aac",
@@ -48,12 +86,13 @@ def render_final_video(
 
         "-shortest",
 
-        "-pix_fmt",
-        "yuv420p",
-
         output
     ]
 
+    print("\nFFMPEG COMMAND:")
+    print(" ".join(cmd))
+    print()
+
     result = subprocess.run(
         cmd,
         capture_output=True,
@@ -63,4 +102,47 @@ def render_final_video(
     print(result.stdout)
     print(result.stderr)
 
-    result.check_returncode()
+    result.check_returncode()
+
+    if not os.path.exists(output):
+        raise Exception(
+            "Final video not generated"
+        )
+
+    probe = subprocess.run(
+        [
+            "ffprobe",
+            "-v",
+            "error",
+
+            "-show_entries",
+            "format=duration",
+
+            "-of",
+            "default=noprint_wrappers=1:nokey=1",
+
+            output
+        ],
+        capture_output=True,
+        text=True
+    )
+
+    print("=" * 50)
+    print("FINAL VIDEO DURATION")
+    print("=" * 50)
+    print(probe.stdout)
+
+    size_mb = (
+        os.path.getsize(output)
+        / 1024
+        / 1024
+    )
+
+    print("=" * 50)
+    print("OUTPUT SIZE")
+    print("=" * 50)
+    print(
+        f"{size_mb:.2f} MB"
+    )
+
+    return output