File Formats

Two native file formats are provided by EazyDraw. One is a XML like format called a Property List, the other is a more compact and quicker to load and save binary format. GZip compression may be used with either format. All formats are loss-less, all drawing information is faithfully recorded.

The EazyDraw Graphics format is an OS X Property List, a XML like format. The drawing information is, for the most part, a human readable text document. A text editor like BBedit or Simple Text can be used to view and modify the files. There is an Apple provided Property List Editor available which may be used to view and edit the XML dictionary elements of the file. This native EazyDraw Graphics Format has the extension ".ezdraw".

The EazyDraw binary format results in approximately 10 fold smaller files. This can be important for drawings containing large numbers of graphics, in excess of 500 graphic elements. The smaller size will greatly reduce the time required to save or open the file. The extension for this format is "ezdata" and the Kind displayed by the operating system is "EazyDraw Compressed" . The "Compressed" nomenclature is a slight misnomer, but the meaning of the term is better understood that the technical jargon of "Binary" .

The file format is selected from the popup menu found on the lower portion of the save panel. Select the desired format before clicking the Save Button.

Use EazyDraw Graphics format for normal file saves of smaller drawings and for all archival purposes.

Use EazyDraw Binary format for larger files when File Save and File open times become noticeable.

Use GZip compression with either format for email attached drawings.

Do NOT use the binary format or GZip compression for archival purposes. EazyDraw Graphics format should be used for the final master copy save of a project, if at all possible.

EazyDraw Graphics format files have a blue colored file Icon showing a box of graphic components. The EazyDraw binary format file icon is the same graphic but gray in color. GZipped files show the icon corresponding to the uncompressed component of the file. See the examples below.

When archiving drawings, saving them for possible future use including the distant future, it is best to use the Eazydraw Graphics Format. This is a little counter intuitive as these files will be much larger. But one should consider that size is not that important a consideration for current and future archiving media. The predominate factor is to be rather certain that the data can be read in the future, probably on a different CPU with a different version of EazyDraw, another drawing application or different operating system. The human readable text format is important for this task. If a file is corrupted, any text editor can be used to locate and correct the corruption. But if this happens to the binary data or a compressed file, detection and correction is nearly impossible.

The Save As menu command is needed to change the file save format. The current file format becomes part of the file information, hence a simple save will conveniently save the drawing using the last file format. Save As provides the opportunity to change format or compression options.

When switching to a new version of EazyDraw,it is recommended to save important drawings in the EazyDraw graphics format with the old version. We try to make all version changes transparent for our file format, but bugs are always possible, especially for backwards compatible legacy format issues. If a problem does occur, it can always be addressed by one of our technicians -- if the EazyDraw Graphics format is available; however nothing can usually be done with the binary form or a GZip compressed file.

GZip is ideal for emailing a drawing. It doesn't mater a great deal if the larger Graphics format is compressed or if compression is applied to the binary format. While a binary format is more compact, the text based format is extremely repetitive which leads to larger compression ratio's. A larger sized EazyDraw Graphics format file may sometimes compress by as much as 99 percent. GZip is a good compression algorithm, but not the best available when considering ultimate smallest file size. GZip is, however, in wide use and will likely uncompress properly on any operating system. For ultimate small file size, the gzipped or raw file may be compressed with specialized compression applications like Stufit.

A note on File Size: The modern XML like structure of the EazyDraw Graphics format is not size efficient. A small single page drawing can easily be 1-2 MBytes, which would have been a big problem on computers of the 70's and 80's. However current computing and storage media resources are not taxed by this inefficiency. The root storage format and data organization for vector drawing is quite repetitive. This means that the files are very amenable to common compression algorithms. If a small file is absolutely needed, loss-less compression is readily available -- just avoid this for archiving. Some of the design trade-offs provided by the larger file size are: full storage of all nuances of the drawing state and user preferences, ease of data recovery from software bugs or hardware failure, enhanced backwards compatibility and seamless transition to revised and improved content format (no rev 1 and rev 2 file formats), self documenting - human readable file content for full access by current and future technicians.

All formats and the GZip compression are registered with OS X. Files saved with any combination of formats and compression are recognized and associated with EazyDraw by the System Finder. A Finder Double click on any of these files will call up EazyDraw to open the file. The .gz extension is understood by OS X and the finder, calls to Get Info look past the .gz to the original information.

Most information in an EazyDraw Graphics format file is human (english) readable text. Oddly enough, text that is represented in the file is not readable, text information, including the actual text plus font and formatting information is saved in "Rich Text Format" (RTF), which is a binary format. This is a quirk of OS X and the software industry, this may be improved in the future, but for todays technology RTF binary is best.

Finally: the EazyDraw Graphics Format is recommended over all others, unless the save time becomes a problem. If anything untoward happens to a file in this format, it is possible to correct the problem and salvage most or all of the drawing content. Drawings saved in the EazyDraw Compressed Format are not easily recovered in the event of data corruption.