pdf to jpg Error

[zsunsky]

[root@izwz9hw7653yyqpqm5qv80z test]# convert -version
Version: ImageMagick 7.0.7-25 Q16 x86_64 2018-10-07 http://www.imagemagick.org
Copyright: © 1999-2018 ImageMagick Studio LLC
License: http://www.imagemagick.org/script/license.php
Features: Cipher DPC HDRI OpenMP
Delegates (built-in): bzlib freetype jpeg tiff x zlib

[root@izwz9hw7653yyqpqm5qv80z test]# dir
1.jpg 2.jpg test01.pdf test02.PDF test111.jpg test111.tiff test47.php test.pdf test.tiff

[root@izwz9hw7653yyqpqm5qv80z test]# convert test01.pdf test01.jpg
convert: no decode delegate for this image format `PNG' @ error/constitute.c/ReadImage/509.
convert: no images defined `test01.jpg' @ error/convert.c/ConvertImageCommand/3275.



What is the reason for the mistake?

[snibgo]

Delegates (built-in): bzlib freetype jpeg tiff x zlib

You don't have the PNG built-in delegate. I guess you built IM yourself, but didn't install libpng first. config.log should tell you.

[zsunsky]

Libpng is installed, but the problem is still there. What needs to be set up?

[zsunsky]

Installation is no problem

[zsunsky]

[root@izwz9hw7653yyqpqm5qv80z test]# dir
erp.pdf test01.pdf test02.PDF test47.php test.pdf
[root@izwz9hw7653yyqpqm5qv80z test]# convert test.pdf test.png
[root@izwz9hw7653yyqpqm5qv80z test]# dir
erp.pdf test01.pdf test02.PDF test47.php test.pdf test.png UC026158315HK.pdf
[root@izwz9hw7653yyqpqm5qv80z test]# convert UC026158315HK.pdf uc000.png
convert: no images defined `uc000.png' @ error/convert.c/ConvertImageCommand/3275.

What is the reason for the mistake?