{"id":8,"date":"2005-11-26T03:09:55","date_gmt":"2005-11-25T23:20:57","guid":{"rendered":""},"modified":"2017-03-07T15:55:50","modified_gmt":"2017-03-07T15:55:50","slug":"adjusting_exif_date_time_with_jhead","status":"publish","type":"post","link":"https:\/\/blogs.gentoo.org\/agriffis\/2005\/11\/26\/adjusting_exif_date_time_with_jhead\/","title":{"rendered":"Adjusting Exif Date\/Time with jhead"},"content":{"rendered":"<p>Working on some digital photos today, I found the Date\/Time field in the Exif header was set to EDT, because that&#8217;s how my camera was set (I&#8217;ve changed it now to UTC).  This is problematic because I recently took a trip to Italy, and of course the times on those photos don&#8217;t make sense:<\/p>\n<blockquote>\n<pre>$ jhead IMG_0356.JPG | grep ^Date\r\nDate\/Time    : 2005:09:20 09:46:49\r\n<\/pre>\n<\/blockquote>\n<p>To get the times changed to UTC on my existing pictures, I used the following sequence:<\/p>\n<blockquote>\n<pre>$ jhead -ta+4:00 *.JPG\r\n$ TZ=UTC jhead -ft *\/*.JPG\r\n<\/pre>\n<\/blockquote>\n<p>The first command advances the Exif Date\/Time on all the pictures by 4 hours, which is the difference between EDT and UTC.  The second command copies the Exif Date\/Time to the file&#8217;s mtime, pretending that we&#8217;re presently in UTC so that it doesn&#8217;t attempt to adjust.  The final result is:<\/p>\n<blockquote>\n<pre>$ jhead IMG_0356.JPG | grep ^Date\r\nDate\/Time    : 2005:09:20 13:46:49\r\n$ ls -l IMG_0356.JPG\r\n-rw-r--r--  1 agriffis agriffis 3.9M Sep 20 09:46 IMG_0356.JPG\r\n<\/pre>\n<\/blockquote>\n","protected":false},"excerpt":{"rendered":"<p>Working on some digital photos today, I found the Date\/Time field in the Exif header was set to EDT, because that&#8217;s how my camera was set (I&#8217;ve changed it now to UTC). This is problematic because I recently took a trip to Italy, and of course the times on those photos don&#8217;t make sense: $ &hellip; <a href=\"https:\/\/blogs.gentoo.org\/agriffis\/2005\/11\/26\/adjusting_exif_date_time_with_jhead\/\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">Adjusting Exif Date\/Time with jhead<\/span><\/a><\/p>\n","protected":false},"author":25,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[4],"tags":[],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/blogs.gentoo.org\/agriffis\/wp-json\/wp\/v2\/posts\/8"}],"collection":[{"href":"https:\/\/blogs.gentoo.org\/agriffis\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.gentoo.org\/agriffis\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.gentoo.org\/agriffis\/wp-json\/wp\/v2\/users\/25"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.gentoo.org\/agriffis\/wp-json\/wp\/v2\/comments?post=8"}],"version-history":[{"count":1,"href":"https:\/\/blogs.gentoo.org\/agriffis\/wp-json\/wp\/v2\/posts\/8\/revisions"}],"predecessor-version":[{"id":16,"href":"https:\/\/blogs.gentoo.org\/agriffis\/wp-json\/wp\/v2\/posts\/8\/revisions\/16"}],"wp:attachment":[{"href":"https:\/\/blogs.gentoo.org\/agriffis\/wp-json\/wp\/v2\/media?parent=8"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.gentoo.org\/agriffis\/wp-json\/wp\/v2\/categories?post=8"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.gentoo.org\/agriffis\/wp-json\/wp\/v2\/tags?post=8"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}