Settings»Image Conversion Settings

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Qdig Image Conversion Settings

Writable Directories

Folders containing your original images may be read-only by the web server daemon, but the script needs write permissions to write empty caption .txt files and converted-image files (thumbnail and alternate-sized images).

$qdig_files = 'qdig-files/';
This specifies the root of the writable tree. Setup is easy: Create the directory. Give it 2777 permissions (`chmod 2777'). Visit the gallery once. Then change the permissions to something sane (0755).
$convrtd_subdir = 'converted-images/';
Subdirectory to use for resampled images
$caption_subdir = 'captions';
Subdirectory to use for captions
$touch_captions = TRUE;
Causes Qdig to automatically create empty caption .txt files if none exists for a particular image.

Image Magick and GD Settings

If you have both Image Magick and PHP's GD extensions available for image conversion, Qdig uses IM except on a Win32 server. To use the one that isn't the default, set the default one to FALSE and, on Win32, set $convert_cmd appropriately.

$convert_magick = TRUE;
Use Image Magick, if available, to convert images.
$convert_cmd = '/usr/bin/convert';
Full pathname to Image Magick's `convert' executable
$convert_nice = TRUE;
Modify priority with nice(1) command if available.
$nice_command = '/bin/nice -n 18 ';
Full pathname to `nice' executable
$convert_GD = TRUE;
Use PHP's built-in GD image-handling extensions, if available, to convert images.
$convert_GD_ver = '';
Specify the GD version available. '' is auto-detect (recommended). Else '1' or '2'.

Sizes to convert / display

Enable or disable any of the alternate sizes.

These cause the resizing links in the Control Bar and Navigation Bar to disappear if set to FALSE and appear if set to TRUE.

$disp_size[0] = FALSE;
'XS' - Extra-small is for an included gallery in a blog site.
$disp_size[1] = FALSE;
'S' - Small is for low-bandwidth sites.
$disp_size[2] = TRUE;
'M' - Medium is about right for 1024x768 displays.
$disp_size[3] = FALSE;
'L' - Large is about right for 1280x960 displays.
$disp_size[4] = FALSE;
'XL' - Extra-large is fairly large for a web-displayed image. A typical digicam photo resizes to 960x720 pixels.
$disp_size[5] = TRUE;
'FS' - Full-sized displays the originals, whatever size they are.
$default_img_size = '2';
If no size is specified, default to the size specified in this setting. '2' (Medium) is the default. The size used here must be an enabled size.

Thumbnail Image Conversion Settings

$cnvrt_thmb['size'] = 50;
Specifies the thumbnail image height in pixels. Sizes: 10 is tiny, 20 is small, 35 is medium, 50 is large, 75 is jumbo
$cnvrt_thmb['qual'] = 60;
Specifies the thumbnail image quality. If you increase this a bit from the default of 60, large thumbnails may look better but they will have increased file size.
$cnvrt_thmb['sharpen'] = '0.6x0.6';
Specifies the level of sharpening for thumbnails.
$cnvrt_thmb['single'] = FALSE;
Have Qdig convert a thumb in a singleton directory.
$cnvrt_thmb['mesg_on'] = FALSE;
Produce a feedback message when a thumbnail image is auto-generated by the script. This tends to be a bit verbose for most, so it's turned off by default.
$cnvrt_thmb['no_prof'] = FALSE;
Strip image profile data (metadata such as EXIF and IPTC data) to reduce the file size of thumbnails, sometimes dramatically, or perhaps for privacy purposes. The only reason it's disabled by default is because it may be incompatible with some servers.
$cnvrt_thmb['prefix'] = "thm{$cnvrt_thmb['size']}_";
Specifies the filename prefix for thumbnail images.The default includes the thumb file size. By including the file size in the name, we automagically get new thumbnails when the thumbnail size is changed.

Alternate-sized Image Conversion Settings

$cnvrt_alt['indiv'] = TRUE;
Convert alternates one-at-a-time rather than all the images in a directory at once.
$cnvrt_alt['mesg_on'] = TRUE;
Produce a message when an image is converted.
$cnvrt_alt['no_prof'] = FALSE;
Strip image profile data (metadata such as EXIF and IPTC data) to reduce the file size of the converted image file or possibly for privacy.
$cnvrt_alt['by_height'] = FALSE;
Convert by height only, not height or width.

The following are the default conversion settings used for the various resampled=image sizes. All of the following are set for each of the sizes.

The filename prefix for the generated file.
The sharpen parameter passed to ImageMagick.
The size setting. Other dimensions are calculated.
The compression quality level.
The image size text used inline in a message. (Language Setting)
The text used for a link. (Language Setting)

Thee defaults have been carefully arrived at through meticulous non-scientific eyeballing of of a wide variety of images. By and large, these settings won't change the general impression conveyed by the original if converted using Image Magick. The sharpening settings are ignored by GD.

// x-small

$cnvrt_size[0]['prefix'] = 'xsm_';
$cnvrt_size[0]['sharpen'] = '0.6x0.7';
$cnvrt_size[0]['maxwid'] = 420;
$cnvrt_size[0]['qual'] = 87;

// small

$cnvrt_size[1]['prefix'] = 'sml_';
$cnvrt_size[1]['sharpen'] = '0.6x0.8';
$cnvrt_size[1]['maxwid'] = 512;
$cnvrt_size[1]['qual'] = 87;

// medium

$cnvrt_size[2]['prefix'] = 'med_';
$cnvrt_size[2]['sharpen'] = '0.6x0.8';
$cnvrt_size[2]['maxwid'] = 640;
$cnvrt_size[2]['qual'] = 89;

// large

$cnvrt_size[3]['prefix'] = 'lrg_';
$cnvrt_size[3]['sharpen'] = '0.6x0.9';
$cnvrt_size[3]['maxwid'] = 800;
$cnvrt_size[3]['qual'] = 90;

// x-large

$cnvrt_size[4]['prefix'] = 'xlg_';
$cnvrt_size[4]['sharpen'] = '0.6x0.9';
$cnvrt_size[4]['maxwid'] = 1024;
$cnvrt_size[4]['qual'] = 91;

// actual

$cnvrt_size[5]['prefix'] = '../';