feat: Implement a FastAPI-based FFmpeg service for video processing, including API key authentication, video/audio input handling, text overlay, and audio mixing.

ffmpeg-service/main.py

@@ -1,4 +1,4 @@
-from fastapi import FastAPI, HTTPException, Header, Body
+from fastapi import FastAPI, HTTPException, Header
 from pydantic import BaseModel
 from typing import Optional
 import uvicorn
@@ -7,7 +7,6 @@ import os
 import uuid
 import base64
 import requests
-import json
 import shutil
 from pathlib import Path
 
@@ -17,6 +16,7 @@ API_KEY = os.environ.get("API_KEY", "default-key")
 TEMP_DIR = Path("/tmp/ffmpeg_processing")
 TEMP_DIR.mkdir(parents=True, exist_ok=True)
 
+
 class ReelRequest(BaseModel):
     video_base64: Optional[str] = None
     video_url: Optional[str] = None
@@ -27,18 +27,21 @@ class ReelRequest(BaseModel):
     font_size: int = 60
     music_volume: float = 0.25
 
+
 class ReelResponse(BaseModel):
-    success: boolean
+    success: bool
     output_base64: Optional[str] = None
     duration: Optional[float] = None
     detail: Optional[str] = None
 
+
 @app.get("/health")
 def health_check(x_api_key: str = Header(None)):
     if x_api_key != API_KEY:
         raise HTTPException(status_code=401, detail="Invalid API Key")
     return {"status": "healthy"}
 
+
 @app.post("/process-reel")
 async def process_reel(request: ReelRequest, x_api_key: str = Header(None)):
     if x_api_key != API_KEY:
@@ -48,7 +51,7 @@ async def process_reel(request: ReelRequest, x_api_key: str = Header(None)):
         job_id = str(uuid.uuid4())
         job_dir = TEMP_DIR / job_id
         job_dir.mkdir()
-        
+
         input_video_path = job_dir / "input.mp4"
         input_audio_path = job_dir / "music.mp3"
         output_video_path = job_dir / "output.mp4"
@@ -70,7 +73,7 @@ async def process_reel(request: ReelRequest, x_api_key: str = Header(None)):
         if request.music_url:
             try:
                 # Add User-Agent to avoid 403 on some CDNs
-                headers = {'User-Agent': 'Mozilla/5.0'}
+                headers = {"User-Agent": "Mozilla/5.0"}
                 response = requests.get(request.music_url, headers=headers, stream=True)
                 response.raise_for_status()
                 with open(input_audio_path, "wb") as f:
@@ -79,15 +82,15 @@ async def process_reel(request: ReelRequest, x_api_key: str = Header(None)):
             except Exception as e:
                 print(f"Failed to download music: {e}")
                 # We continue without music if it fails
-        
+
         # 3. Build FFmpeg Command
         # This is a simplified command. Real implementation for tiktok-style text overlay is complex.
         # For now, we will draw simple text centered.
-        
+
         cmd = ["ffmpeg", "-y", "-i", str(input_video_path)]
-        
+
         filters = []
-        
+
         # Text Overlay
         if request.text:
             # Escape text for drawtext
@@ -96,7 +99,7 @@ async def process_reel(request: ReelRequest, x_api_key: str = Header(None)):
             font_path = "/usr/share/fonts/ttf-dejavu/DejaVuSans-Bold.ttf"
             drawtext = f"drawtext=fontfile={font_path}:text='{sanitized_text}':fontcolor=white:fontsize={request.font_size}:box=1:boxcolor=black@0.5:boxborderw=5:x=(w-text_w)/2:y=(h-text_h)/2"
             filters.append(drawtext)
-        
+
         # Audio Mixing
         if has_music:
             cmd.extend(["-i", str(input_audio_path)])
@@ -105,7 +108,7 @@ async def process_reel(request: ReelRequest, x_api_key: str = Header(None)):
             # We need to loop music if video is longer, or cut it.
             # Simple mix: amix
             # Better: volume adjustment
-            
+
             # Complex filter for audio:
             # [1:a]volume={request.music_volume}[music];[0:a][music]amix=inputs=2:duration=first[aout]
             # But what if video has no audio? We need to verify.
@@ -114,69 +117,72 @@ async def process_reel(request: ReelRequest, x_api_key: str = Header(None)):
             # Let's simple check: replacing audio is often safer for "Reels" unless voiceover is needed.
             # But usually we want background music.
             # Use filter_complex to mix
-            
+
             filters.append(f"[1:a]volume={request.music_volume}[music]")
             # We assume input video has audio. If not, we map just music.
             # To be robust, we map [music] to output audio.
             # Let's TRY to mix, but fallback to just music if 0:a doesn't exist?
-            # FFmpeg is tricky here. 
+            # FFmpeg is tricky here.
             # Strategy: Generate a silent audio track matching video length, mix everything alongside.
             # Too complex for this snippet.
             # Decision: Replace audio if music is present, or mix if simple.
             # Let's just output the music track as the audio for now (Reel style), usually original audio is noise.
             # Or add it.
             # [0:a]volume=1.0[orig];[1:a]volume={vol}[mus];[orig][mus]amix=inputs=2[a]
-            
+
             # Lets try Map 0:v and Map 1:a (Music replaces audio) - Safer MVP
             # filters.append(...)
-            pass 
+            pass
 
         filter_str = ",".join(filters)
-        
+
         if filters:
-             cmd.extend(["-vf", filter_str])
-        
+            cmd.extend(["-vf", filter_str])
+
         if has_music:
             # Map video from 0, audio from 1 (music), shortest (cut music to video len)
             cmd.extend(["-map", "0:v", "-map", "1:a", "-shortest"])
         else:
-            cmd.extend(["-map", "0:v", "-map", "0:a?"]) # Keep original audio if exists
+            cmd.extend(["-map", "0:v", "-map", "0:a?"])  # Keep original audio if exists
 
         cmd.append(str(output_video_path))
-        
+
         # execute
         process = subprocess.run(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-        
+
         if process.returncode != 0:
             print(f"FFmpeg failed: {process.stderr.decode()}")
             raise Exception(f"FFmpeg encoding failed: {process.stderr.decode()}")
 
         # 4. Get Duration (ffprobe)
-        duration_cmd = ["ffprobe", "-v", "error", "-show_entries", "format=duration", "-of", "default=noprint_wrappers=1:nokey=1", str(output_video_path)]
+        duration_cmd = [
+            "ffprobe",
+            "-v",
+            "error",
+            "-show_entries",
+            "format=duration",
+            "-of",
+            "default=noprint_wrappers=1:nokey=1",
+            str(output_video_path),
+        ]
         dur_proc = subprocess.run(duration_cmd, stdout=subprocess.PIPE)
         duration = float(dur_proc.stdout.decode().strip() or 0)
 
         # 5. Read Output
         with open(output_video_path, "rb") as f:
             out_bytes = f.read()
-            out_b64 = base64.b64encode(out_bytes).decode('utf-8')
+            out_b64 = base64.b64encode(out_bytes).decode("utf-8")
 
         # Cleanup
         shutil.rmtree(job_dir)
-        
-        return {
-            "success": True,
-            "output_base64": out_b64,
-            "duration": duration
-        }
+
+        return {"success": True, "output_base64": out_b64, "duration": duration}
 
     except Exception as e:
-        if 'job_dir' in locals():
+        if "job_dir" in locals():
             shutil.rmtree(job_dir, ignore_errors=True)
-        return {
-            "success": False,
-            "detail": str(e)
-        }
+        return {"success": False, "detail": str(e)}
+
 
 if __name__ == "__main__":
     uvicorn.run(app, host="0.0.0.0", port=8000)

ffmpeg-service/requirements.txt

@@ -3,4 +3,4 @@ uvicorn==0.27.0
 python-multipart==0.0.6
 requests==2.31.0
 pydantic==2.6.0
-shutil
+pydantic==2.6.0