I am transcoding video to different quality using ffmpeg using subprocess in Python. I want to make my transcoding faster. I tried multi-threading but it didn't help. Hardware acceleration is not possible as we are using an AWS EC2 t3.large instance at this time, which has 2 CPUs, 8GiB memory, and 30% baseline performance. Can you suggest something maybe regarding the ffmpeg command or update the code?
def transcode_video(video, quality, file_name):
try:
quality_mapping = {
"360p": "640x360",
"480p": "854x480",
"720p": "1280x720",
"1080p": "1920x1080"
}
if quality not in quality_mapping:
raise ValueError(f"Quality '{quality}' not supported")
video_name, video_ext = os.path.splitext(file_name)
# Construct output path with quality suffix
output_path = f"{video_name}_{quality}{video_ext}"
# Create FFmpeg object with streaming
ffmpeg_command = [
'ffmpeg',
'-i', 'pipe:0',
'-vf', f'scale={quality_mapping[quality]}',
'-c:a', 'aac',
'-c:v', 'libx264',
'-preset', 'ultrafast',
'-crf', '23',
'-strict', 'experimental',
output_path
]
# Use subprocess.PIPE for stdin and stdout
with subprocess.Popen(ffmpeg_command, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE) as process:
# Write video content to stdin
process.stdin.write(video.read())
process.stdin.close() # Close stdin to indicate the end of input
# Wait for the process to finish
process.wait()
return output_path
except FileNotFoundError as e:
# Clean up temporary file
# if 'temp_file_path' in locals() and os.path.exists(temp_file_path):
# os.remove(temp_file_path)
# Remove output file after returning
if 'output_path' in locals() and os.path.exists(output_path):
os.remove(output_path)
raise e
except subprocess.CalledProcessError as e:
if 'output_path' in locals() and os.path.exists(output_path):
os.remove(output_path)
raise e
except Exception as e:
if 'output_path' in locals() and os.path.exists(output_path):
os.remove(output_path)
raise e
