Lambda GhostScript错误看起来我们不支持此文件格式

Question

我正在使用下面的代码将.pdf转换为.png，它可以转换，但当我下载并打开文件时，它会说：“看起来我们不支持这种文件格式”

添加了GhostScript二进制作为层，并向lambda添加了S3 bucket触发器

import sys
import os
import boto3
import urllib
import subprocess
import traceback

_SUPPORTED_FILE_EXTENSION = '.pdf'

s3 = boto3.client('s3')

# Absolute path to Ghostscript executable here or command name if Ghostscript is
# in your PATH.
GHOSTSCRIPTCMD = "gs"

def pdf_to_image(event, context):
    
    bucket_name = event['Records'][0]['s3']['bucket']['name']
    s3_file_path = urllib.parse.unquote_plus(event['Records'][0]['s3']['object']['key'], encoding='utf-8')
    
    if not s3_file_path.endswith(_SUPPORTED_FILE_EXTENSION):
        raise Exception("Only .pdf files are supported by this module.")
        
    try:
        pdf_file = '/tmp/input.pdf'
        s3.download_file(bucket_name , s3_file_path, pdf_file)
        
        if os.path.isfile(pdf_file):
            print("Given file downloaded to, Path : {}.".format(pdf_file))
        
        gs_pdf_to_png(pdf_file, 300, s3_file_path)
    except Exception as e:
        raise e

def gs_pdf_to_png(pdffilepath, resolution, s3_file_path):
    if not os.path.isfile(pdffilepath):
        print("Given file dose not exists, Path : {}.".format(pdffilepath))
        
    pdffiledir = os.path.dirname(pdffilepath)
    pdffilename = os.path.basename(pdffilepath)
    pdfname, ext = os.path.splitext(pdffilepath)
 
    try:
        pngpath = "{}-Page%d.png".format(pdfname)
        
        cmd = '%s -dSAFER -sstdout=%%stderr -dBATCH -dNOPAUSE -sDEVICE=png16m -r300 -sOutputFile=%s %s' % (GHOSTSCRIPTCMD, pngpath, pdffilepath)
        print(cmd)
        os.system(cmd)
        
        pngpath = "{}-Page1.png".format(pdfname)
        
        if os.path.isfile(pngpath):
            print("Converted PNG file saved to, Path : {}.".format(pngpath))
            
            DESTS3BUCKET = "Dest-poc1"
            key = "{}{}".format(os.path.dirname(s3_file_path), os.path.basename(pngpath))
            
            print("Uploading PNG file to destination Bucket : {}, Key : {}.".format(DESTS3BUCKET, key))
            
            s3.put_object(Body=pngpath, Bucket=DESTS3BUCKET, Key=key)
            
    except OSError as e:
        print("OSError while running Ghostscript subprocess. err: {}".format(e))
        raise e
    except Exception as e:
        print("Error while running Ghostscript subprocess. err: {}".format(e))
        raise e

我花了很多时间来解决这个问题，但是运气不好，如果你愿意，请帮我解决

提前谢谢