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.IX Title "Image::ExifTool::JPEGDigest 3pm"
.TH Image::ExifTool::JPEGDigest 3pm "2021-04-26" "perl v5.28.1" "User Contributed Perl Documentation"
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
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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 \s-1JPEG DQT\s0 digest, allowing
some image identification from \s-1JPEG\s0 data alone.  It also calculates an
estimated \s-1JPEG\s0 quality if requested.
.SH "AUTHOR"
.IX Header "AUTHOR"
Copyright 2003\-2018, Phil Harvey (phil at owl.phy.queensu.ca)
.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"
\&\*(L"\s-1JPEG\s0 Tags\*(R" in Image::ExifTool::TagNames,
\&\fBImage::ExifTool\fR\|(3pm)