1Image::ExifTool::AFCP(3U)ser Contributed Perl DocumentatiIomnage::ExifTool::AFCP(3)
2
3
4

NAME

6       Image::ExifTool::AFCP - Read/write AFCP trailer
7

SYNOPSIS

9       This module is used by Image::ExifTool
10

DESCRIPTION

12       This module contains definitions required by Image::ExifTool to extract
13       information from the AFCP trailer.  Although the AFCP specification is
14       compatible with various file formats, ExifTool currently only processes
15       AFCP in JPEG images.
16

NOTES

18       AFCP is a specification which allows meta information (including IPTC)
19       to be appended to the end of a file.
20
21       It is a poorly designed protocol because (like TIFF) it uses absolute
22       offsets to specify data locations.  This is a huge blunder because it
23       makes the AFCP information dependent on the file length, so it is
24       easily invalidated by image editing software which doesn't recognize
25       the AFCP trailer to fix up these offsets when the file length changes.
26       ExifTool will attempt to fix these invalid offsets if possible.
27
28       Scanning for AFCP information may be time consuming, especially when
29       reading from a sequential device, since the information is at the end
30       of the file.  In these instances, the ExifTool FastScan option may be
31       used to disable scanning for AFCP information.
32

AUTHOR

34       Copyright 2003-2019, Phil Harvey (phil at owl.phy.queensu.ca)
35
36       This library is free software; you can redistribute it and/or modify it
37       under the same terms as Perl itself.
38

REFERENCES

40       <http://www.tocarte.com/media/axs_afcp_spec.pdf>
41

SEE ALSO

43       "AFCP Tags" in Image::ExifTool::TagNames, Image::ExifTool(3pm)
44
45
46
47perl v5.28.1                      2019-01-10          Image::ExifTool::AFCP(3)
Impressum