diff options
Diffstat (limited to 'graphics/jpeg/files/patch-jpegtran.1')
| -rw-r--r-- | graphics/jpeg/files/patch-jpegtran.1 | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/graphics/jpeg/files/patch-jpegtran.1 b/graphics/jpeg/files/patch-jpegtran.1 new file mode 100644 index 000000000000..fe4eb1372f4d --- /dev/null +++ b/graphics/jpeg/files/patch-jpegtran.1 @@ -0,0 +1,44 @@ +--- jpegtran.1.exif 1997-08-03 22:01:01.000000000 +0200 ++++ jpegtran.1 2003-09-30 14:35:36.000000000 +0200 +@@ -161,6 +161,14 @@ + Copy all extra markers. This setting preserves miscellaneous markers + found in the source file, such as JFIF thumbnails and Photoshop settings. + In some files these extra markers can be sizable. ++See 'EXIF FILES' for special tratement of EXIF markers. ++.TP ++.B \-copy exif ++This setting preserves the EXIF marker, commonly found in JPEG files produced ++by digital cameras, in addition to any comment markers. If there is an EXIF ++marker it is copied and the JFIF marker (incompatible with EXIF) is ++omitted. If there is no EXIF marker a JFIF one is emitted as usual. See 'EXIF ++FILES' for special tratement of EXIF markers. + .PP + The default behavior is + .BR "\-copy comments" . +@@ -189,6 +197,26 @@ + .B \-debug + Same as + .BR \-verbose . ++.SH EXIF FILES ++The EXIF variety of JPEG files, which are often produced by digital cameras, ++are recognized by jpegtran as EXIF files (i.e. not as JFIF, the ++usual variety of JPEG files). If the input file is recognized as EXIF (i.e., ++there is an EXIF marker and no JFIF marker) the '-copy exif' option is ++automatically turned on if '-copy comments', or no '-copy' option, was ++specified. Thus, unless '-copy none' is specified an EXIF file is kept as EXIF ++and not converted to JFIF. ++.PP ++If a geometrical transformation is applied (e.g., rotate, transpose) the EXIF ++width and height fields are set to the width and height of the output ++image. Furthermore, the orientation field is reset to one, meaning tha the ++orientation of the output image is upright (i.e. normal). ++.PP ++Note that an explicitely given '-copy exif' option will output an EXIF file if ++the input is an EXIF file that was saved as JFIF, and that the EXIF marker is ++still present. This option is useful for recovering EXIF files that where ++converted to JFIF by a non EXIF-aware software. Note however, that the data in ++the EXIF marker is not validated, unless a geometrical transformation is ++applied. + .SH EXAMPLES + .LP + This example converts a baseline JPEG file to progressive form: |