optional exif support (build with exif=1), initial patch import

1 files changed, 197 insertions, 0 deletions

diff --git a/src/exif.c b/src/exif.c
new file mode 100644
index 0000000..02154e4
--- /dev/null
+++ b/src/exif.c
@@ -0,0 +1,197 @@
+/* exif.c
+
+Copyright (C) 2012      Dennis Real.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to
+deal in the Software without restriction, including without limitation the
+rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies of the Software and its documentation and acknowledgment shall be
+given in the documentation and software packages that this Software was
+used.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+*/
+
+#ifdef HAVE_LIBEXIF
+
+#include <stdio.h>
+#include <string.h>
+#include <libexif/exif-data.h>
+
+#include "feh.h"
+#include "options.h"
+#include "debug.h"
+#include "exif.h"
+
+
+
+/* remove all spaces on the right end of a string */
+static void exif_trim_spaces(char *str)
+{
+  char *end;
+  
+  for (end = str; *str!='\0'; str++) 
+  {
+    if (*str != ' ')
+    {
+      end = str;
+    }
+  }
+  *++end = '\0';
+}
+
+
+/* show given exif tag content */
+static void exif_get_tag(ExifData *d, ExifIfd ifd, ExifTag tag, char* buffer, unsigned int maxsize)
+{
+  char s[MAX_EXIF_DATA];
+
+  if ( (d != NULL) && (buffer != NULL) && (maxsize>0) )
+  {
+    ExifEntry *entry = exif_content_get_entry(d->ifd[ifd], tag);
+    if (entry != NULL) 
+    {
+      /* Get the contents of the tag in human-readable form */
+      exif_entry_get_value(entry, s, maxsize);
+
+      /* Don't bother printing it if it's entirely blank */
+      exif_trim_spaces(s);
+      if (*s != '\0')
+      {
+        D(("%s: %s\n", exif_tag_get_name_in_ifd(tag,ifd), s));
+        snprintf(buffer, (size_t)maxsize, "%s: %s\n", exif_tag_get_name_in_ifd(tag,ifd), s);
+      }
+    }
+  }
+}
+
+
+
+/* Show the given MakerNote tag if it exists */
+static void exif_get_mnote_tag(ExifData *d, unsigned int tag, char* buffer, unsigned int maxsize)
+{
+  ExifMnoteData *mn = NULL; 
+  int i, num;
+  char buf[1024];
+
+  if ( (d!=NULL) && (buffer!=NULL) && (maxsize > 0) )
+  {
+    mn = exif_data_get_mnote_data(d);
+  }
+  else
+  {
+    return;
+  }
+    
+  if ( mn != NULL ) 
+  {
+    num = exif_mnote_data_count(mn);
+
+    /* Loop through all MakerNote tags, searching for the desired one */
+    for (i=0; i < num; ++i) 
+    {
+      if (exif_mnote_data_get_id(mn, i) == tag) 
+      {
+        if (exif_mnote_data_get_value(mn, i, buf, sizeof(buf))) 
+        {
+          /* Don't bother printing it if it's entirely blank */
+          exif_trim_spaces(buf);
+          if (*buf != '\0')
+          {
+             snprintf(buffer, (size_t)maxsize, "%s: %s\n", exif_mnote_data_get_title(mn, i), buf);
+          }
+        }
+      }
+    }
+  }
+}
+
+
+
+/* return data structure with exif data if available */
+ExifData * exif_get_data(char *path)
+{
+  ExifData *ed = NULL;
+
+  /* Load an ExifData object from an EXIF file */
+  ed = exif_data_new_from_file(path);
+  if (ed == NULL)
+  {
+    D(("File not readable or no Exif data present in %s\n", path));
+  }
+
+  return(ed);
+}
+
+
+
+/* get exif data in readable form */
+void exif_get_info(ExifData * ed, char *buffer, unsigned int maxsize)
+{
+  ExifEntry *entry = NULL;
+  char buf[64];
+
+  if ( (buffer == NULL) || (maxsize == 0) )
+  {
+    return;
+  }
+  else if (ed == NULL )
+  {
+    snprintf(buffer, (size_t)maxsize, "%s\n", "No Exif data in file.");
+    return;
+  }
+  else if ( ed != NULL )
+  {
+    /* normal exif tags */
+    exif_get_tag(ed, EXIF_IFD_0, EXIF_TAG_MAKE, buffer, maxsize);
+    exif_get_tag(ed, EXIF_IFD_0, EXIF_TAG_MODEL, buffer + strlen(buffer), maxsize - strlen(buffer));
+    exif_get_tag(ed, EXIF_IFD_0, EXIF_TAG_IMAGE_DESCRIPTION, buffer + strlen(buffer), maxsize - strlen(buffer));
+    exif_get_tag(ed, EXIF_IFD_EXIF, EXIF_TAG_DATE_TIME_ORIGINAL, buffer + strlen(buffer), maxsize - strlen(buffer));
+    exif_get_tag(ed, EXIF_IFD_EXIF, EXIF_TAG_DATE_TIME_DIGITIZED, buffer + strlen(buffer), maxsize - strlen(buffer));
+    exif_get_tag(ed, EXIF_IFD_EXIF, EXIF_TAG_EXPOSURE_TIME, buffer + strlen(buffer), maxsize - strlen(buffer));
+    exif_get_tag(ed, EXIF_IFD_EXIF, EXIF_TAG_SHUTTER_SPEED_VALUE, buffer + strlen(buffer), maxsize - strlen(buffer));
+    exif_get_tag(ed, EXIF_IFD_EXIF, EXIF_TAG_FNUMBER, buffer + strlen(buffer), maxsize - strlen(buffer));
+    exif_get_tag(ed, EXIF_IFD_EXIF, EXIF_TAG_APERTURE_VALUE, buffer + strlen(buffer), maxsize - strlen(buffer));
+    exif_get_tag(ed, EXIF_IFD_EXIF, EXIF_TAG_EXPOSURE_BIAS_VALUE, buffer + strlen(buffer), maxsize - strlen(buffer));
+    exif_get_tag(ed, EXIF_IFD_EXIF, EXIF_TAG_ISO_SPEED_RATINGS, buffer + strlen(buffer), maxsize - strlen(buffer));
+    exif_get_tag(ed, EXIF_IFD_EXIF, EXIF_TAG_FOCAL_LENGTH, buffer + strlen(buffer), maxsize - strlen(buffer));
+    exif_get_tag(ed, EXIF_IFD_EXIF, EXIF_TAG_FOCAL_LENGTH_IN_35MM_FILM, buffer + strlen(buffer), maxsize - strlen(buffer));
+    exif_get_tag(ed, EXIF_IFD_EXIF, EXIF_TAG_EXPOSURE_MODE, buffer + strlen(buffer), maxsize - strlen(buffer));
+    exif_get_tag(ed, EXIF_IFD_EXIF, EXIF_TAG_EXPOSURE_PROGRAM, buffer + strlen(buffer), maxsize - strlen(buffer));
+    exif_get_tag(ed, EXIF_IFD_EXIF, EXIF_TAG_SCENE_CAPTURE_TYPE, buffer + strlen(buffer), maxsize - strlen(buffer));
+    exif_get_tag(ed, EXIF_IFD_EXIF, EXIF_TAG_FLASH, buffer + strlen(buffer), maxsize - strlen(buffer));
+    exif_get_tag(ed, EXIF_IFD_EXIF, EXIF_TAG_FLASH_ENERGY, buffer + strlen(buffer), maxsize - strlen(buffer));
+
+    /* vendor specific makernote tags */
+    entry = exif_content_get_entry(ed->ifd[EXIF_IFD_0], EXIF_TAG_MAKE);
+    if (entry != NULL) 
+    {
+                
+      if (exif_entry_get_value(entry, buf, sizeof(buf))) 
+      {
+        exif_trim_spaces(buf);
+        
+        /* Nikon */                                    
+        if ( strcmp(buf, "Nikon") != 0 )
+        {
+          /* Digital Vari-Program */
+          exif_get_mnote_tag(ed, 171, buffer + strlen(buffer), maxsize - strlen(buffer));
+        }
+
+      }
+    }
+  }
+}
+
+#endif