Resolutions Registry entry

Specify what resolutions are automatically generated when an image is added to a Multimedia record.

Description

When an image is added to a Multimedia record it is possible to have other image formats and sizes generated automatically.

Usage

This Registry entry can be assigned to users, groups and system-wide:

Key User Group System
Key 1 User Group System
Key 2 user group Setting
Key 3 Setting Multimedia
Key 4 Multimedia Resolutions
Key 5 Resolutions format or Default
Key 6 format or Default  
Value generate;generate;...
User user Setting Multimedia Resolutions format generate;generate;...
Group group Setting Multimedia Resolutions format generate;generate;...
System Setting Multimedia Resolutions format generate;generate;...
User user Setting Multimedia Resolutions Default generate;generate;...
Group group Setting Multimedia Resolutions Default generate;generate;...
System Setting Multimedia Resolutions Default generate;generate;...

where:

format

is the format of an image added to a Multimedia record; or use Default for any image format added to a Multimedia record.

Image formats recognised by EMu include:

BMP

Windows bitmap format (.bmp)

GIF

Graphics Interchange format (.gif)

JPEG

Joint Photographic Experts Group (.jpeg, .jpg)

PCX

ZSoft Paint (.pcx)

PNG

Portable Network Graphics (.png)

TGA

Targa (.tga)

TIFF

Tag Image File Format (.tif, .tiff) with the following compressions:

  • None - No compression
  • Fax3 - CCITT Group 3
  • Fax4 - CCITT Group 4
  • LZW
  • PackBits

Other image formats are supported via external viewers. If an image format is not supported internally, a placeholder icon will display wherever the media is shown. Double-clicking the icon will launch an associated external viewer (as defined in the Windows Registry). EMu also provides support for image translation between any of the formats listed above. Other formats may be translated by external programs either on the client machine or the EMu server.

generate;generate;...

is a semicolon separated list of image specifications to be generated in the format:

width:height:format[:scaled[:enlarge[:compression[:quality[:auto-orient]]]]]

where:
width

is the width of the image to be generated in pixels. If the image is not scaled, this is the actual width. For scaled images this is the maximum width. A value of 0 sets the width to the same as the original image.

height

is the height of the image to be generated in pixels. If the image is not scaled, this is the actual height. For scaled images this is the maximum height. A value of 0 sets the height to the same as the original image.
format

is the format of the image to generate. Available values are:

  • BMP
  • GIF
  • JPG
  • JPEG
  • PCX
  • PNG
  • TGA
  • TIF
  • TIFF

scaled

is optional. Takes a value of true or false. If scaled is true, the aspect ratio of the original image will be maintained. This means that either the width or height will be adjusted automatically to ensure the image is not "stretched". If scaled is false, the image will be "stretched" to fill the specified width and height. If this property is not defined, scaling is enabled.
enlarge

is optional. Takes a value of true or false. If enlarge is true, the image will be generated even if the width and / or height are larger than the original image. This may result in image pixilation. A false value will not generate an image if the resulting image would be larger than the original. If this property is not defined, enlarge is enabled.

compression

is optional. The internal compression to be used for storing the image. Alternative compressions are only available for TIFF format. The available values are:

  • None
  • FAX3
  • FAX4
  • LZW
  • PACKBITS

    The default value for TIFF images is None.

quality

is optional. A compression quality value for jpeg / jpg formatted images. A value between 100 and 1 is allowed, where 100 is lossless compression and 1 very lossy compression. If no value is entered, a value of 100 (i.e. lossless) is assumed. See second entry below.

auto-orient

is optional. Takes a value of true or false. If auto-orient is true, and the image includes an EXIF Orientation tag, the image is automatically adjusted by rotation and / or mirroring as appropriate so that the image is oriented correctly with respect to the Orientation tag. The EXIF Orientation tag for the generated resolution is reset to 1 (i.e. top-left orientation) to reflect the adjustment. If auto-orient is false, then no adjustments are made to the image or its Orientation tag. If this property is not defined, auto-orient is enabled.

Examples

This entry specifies the creation of two additional images when an image is added to a Multimedia record. The first is a JPEG image, 640 pixels wide by 480 pixels high, where the aspect ratio is maintained and the image may be enlarged if the original is smaller than 640 x 480 pixels. The second image is a PNG image, 150 pixels wide by 150 pixels high, where the aspect ratio is not maintained (i.e. the image may become distorted) and enlargement is possible:

Key Setting
Key 1 System
Key 2 Setting
Key 3 Multimedia
Key 4 Resolutions
Key 5 Default
Value 640:480:JPG:true:true;150:150:PNG:false:true

Note: The standard EMu thumbnail image is still generated.

The first image may be used as the "full size" image on a website, whereas the second may be a "thumbnail" image for a website. Note that the standard EMu thumbnail image would still be generated. It is effectively an entry in the format 90:90:JPG:true:true.

This entry will also generate two images. The first is a 600x800 JPG with a compression quality of 85%:

Key Setting
Key 1 System
Key 2 Setting
Key 3 Multimedia
Key 4 Resolutions
Key 5 Default
Value 600:800:JPG:true:false:NONE:85;300:400:jpg:true