Picsel Image File Format Support
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ePAGE supports the most popular global file formats. The formats
interpreted by ePAGE are richly expressive, containing not just text but
sophisticated layout and rendering features, rich fonts, colour, images,
tables, graphics and many other document features. Picsel is
continuously developing its file format support to eventually cover every
feature of the native file. With such a wealth of features across many
document types, this is inevitably an ongoing process, with milestone
releases of new functionality planned at periodic intervals. The
approach involves researching the feature set most commonly found in
real documents, building support early for the most frequently used
elements, and ensuring these features are reproduced with total
faithfulness to the original. The emphasis of ePAGE is on displaying rich
content rather than on reproducing the document creation facilities of
the original application.
This document describes the features supported in ePAGE. This level of
support already covers the vast majority of characteristics that occur in
day to day documents of this type, and the specific features are
described with notes where appropriate. Those features planned for
future implementation are also described, for completeness.
Bitmap Images
A bitmap image is a picture made up of a grid of pixels (dots), as
compared to a vector path which is made up of lines between
coordinates. There are a number of file formats popular for storing
bitmap images, each with benefits and drawbacks to consider. The main
image formats supported by ePAGE are JPEG, GIF, PNG and BMP.
Many document formats, such as HTML and Word, allow bitmap
images to be included in various other formats, and do not directly
define them. This is convenient as it allows specialists (such as the Joint
Photographic Experts Group) in image compression and other areas to
define the image formats separately from the document formats,
although the extra network delay of requesting a separate file may
become an issue.
