diff options
Diffstat (limited to 'lisp/image/exif.el')
| -rw-r--r-- | lisp/image/exif.el | 32 |
1 files changed, 25 insertions, 7 deletions
diff --git a/lisp/image/exif.el b/lisp/image/exif.el index 23f11bd87cc..fd4673dc1b6 100644 --- a/lisp/image/exif.el +++ b/lisp/image/exif.el @@ -58,6 +58,9 @@ ;; (:tag 306 :tag-name date-time :format 2 :format-type ascii ;; :value "2019:09:21 16:22:13") ;; ...) +;; +;; (exif-field 'date-time (exif-parse-file "test.jpg")) => +;; "2022:09:14 18:46:19" ;;; Code: @@ -65,6 +68,7 @@ (defvar exif-tag-alist '((11 processing-software) + (270 description) (271 make) (272 model) (274 orientation) @@ -73,7 +77,8 @@ (296 resolution-unit) (305 software) (306 date-time) - (315 artist)) + (315 artist) + (33432 copyright)) "Alist of tag values and their names.") (defconst exif--orientation @@ -95,7 +100,10 @@ mirrored or not.") "Parse FILE (a JPEG file) and return the Exif data, if any. The return value is a list of Exif items. -If the data is invalid, an `exif-error' is signaled." +If the data is invalid, an `exif-error' is signaled. + +Also see the `exif-field' convenience function to extract data +from the return value of this function." (with-temp-buffer (set-buffer-multibyte nil) (insert-file-contents-literally file) @@ -105,7 +113,10 @@ If the data is invalid, an `exif-error' is signaled." "Parse BUFFER (which should be a JPEG file) and return the Exif data, if any. The return value is a list of Exif items. -If the data is invalid, an `exif-error' is signaled." +If the data is invalid, an `exif-error' is signaled. + +Also see the `exif-field' convenience function to extract data +from the return value of this function." (setq buffer (or buffer (current-buffer))) (with-current-buffer buffer (if enable-multibyte-characters @@ -122,13 +133,20 @@ If the data is invalid, an `exif-error' is signaled." (when-let ((app1 (cdr (assq #xffe1 (exif--parse-jpeg))))) (exif--parse-exif-chunk app1)))))) +(defun exif-field (field data) + "Return raw FIELD from EXIF. +If FIELD is not present in the data, return nil. +FIELD is a symbol in the cdr of `exif-tag-alist'. +DATA is the result of calling `exif-parse-file'." + (plist-get (seq-find (lambda (e) + (eq field (plist-get e :tag-name))) + data) + :value)) + (defun exif-orientation (exif) "Return the orientation (in degrees) in EXIF. If the orientation isn't present in the data, return nil." - (let ((code (plist-get (cl-find 'orientation exif - :key (lambda (e) - (plist-get e :tag-name))) - :value))) + (let ((code (exif-field 'orientation exif))) (cadr (assq code exif--orientation)))) (defun exif--parse-jpeg () |