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.IX Title "Image::ExifTool::JPEGDigest 3"
.TH Image::ExifTool::JPEGDigest 3 2024-04-05 "perl v5.38.2" "User Contributed Perl Documentation"
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.SH NAME
Image::ExifTool::JPEGDigest \- Calculate JPEGDigest and JPEGQualityEstimate
.SH SYNOPSIS
.IX Header "SYNOPSIS"
This module is used by Image::ExifTool
.SH DESCRIPTION
.IX Header "DESCRIPTION"
This module contains a lookup for values of the JPEG DQT digest, allowing
some image identification from JPEG data alone.  It also calculates an
estimated JPEG quality if requested.
.SH AUTHOR
.IX Header "AUTHOR"
Copyright 2003\-2024, Phil Harvey (philharvey66 at gmail.com)
.PP
This library is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
.SH REFERENCES
.IX Header "REFERENCES"
.IP <https://github.com/ImageMagick/ImageMagick/blob/master/coders/jpeg.c> 4
.IX Item "<https://github.com/ImageMagick/ImageMagick/blob/master/coders/jpeg.c>"
.SH ACKNOWLEDGEMENTS
.IX Header "ACKNOWLEDGEMENTS"
Thanks to Jens Duttke for most of the work that went into this module, and
to Franz Buchinger for the values he added.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
"JPEG Tags" in Image::ExifTool::TagNames,
\&\fBImage::ExifTool\fR\|(3pm)