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 <newt@pobox.com>, <roelofs@users.sf.net>.

       This manual page was written by Kevin M. Rosenberg <kmr@debian.org> for the Debian GNU
       system (but may be used by others). Updated and converted to Perl POD source format by
       Jari Aalto <jari.aalto@cante.net>. 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>.