pngcheck(1)

NAME

   pngcheck - Test PNG image files for corruption, display size, type,
   compression info

SYNOPSIS

     pngcheck [-vqt7f] file.png [file.png [...]]
     pngcheck [-vqt7f] file.mng [file.mng [...]]
     pngcheck -{sx}[vqt7f] file-containing-PNGs...

     Can be used in pipe:

     ... | pngcheck [-sx][vqt7f]

OPTIONS

   -7  Print contents of text chunks, escape chars >=128 (for 7-bit
       terminals).

   -f  Force continuation even after major errors.

   -p  Display contents of PLTE, tRNS, hIST, sPLT and PPLT (can be used
       with -q).

   -q  Test quietly (only output errors).

   -s  Search for PNGs within another file.

   -t  Display contents of tEXt chunks (can be used with -q).

   -v  test verbosely (print most chunk data).

   -x  Search for PNGs and extract them when found.

DESCRIPTION

   pngcheck is the official PNG tester and debugger. Originally designed
   simply to test the CRCs within a PNG image file (e.g., to check for
   ASCII rather than binary transfer), it has been extended to check and
   optionally print almost all the information about a PNG image and to
   verify that it conforms to the PNG specification. It also includes
   partial support for MNG animations.

   It can dump the chunk-level information in the image in human-readable
   form. For example, it can be used to print the basic stats about an
   image (dimensions, bit depth, etc.); to list the color and transparency
   info in its palette; or to extract the embedded text annotations. All
   PNG and JNG chunks are supported, plus almost all MNG chunks
   (everything but PAST, DISC, tERm, DROP, DBYK, and ORDR). This is a
   command-line program with batch capabilities (e.g., pngcheck *.png).

ENVIRONMENT

   None.

FILES

   None.

SEE ALSO

   pngchunkdesc(1) pngchunks(1) pngcomp(1) pngcp(1) pngcrush(1) pnginfo(1)
   pngmeta(1) pngnq(1) pngquant(1) pngsplit(1)

AUTHORS

   Program was written by Greg Roelofs <[email protected]>,
   <[email protected]>.

   This manual page was written by Kevin M. Rosenberg <[email protected]> for
   the Debian GNU system (but may be used by others). Updated and
   converted to Perl POD source format by Jari Aalto
   <[email protected]>. Released under license GNU GPL v2 or (at your
   option) any later version. For more information about license, visit
   <http://www.gnu.org/copyleft/gpl.html>.

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