There are actually 3 ways that Excel puts an image into a workbook. The first is the old way, used by Excel v 4, but still supported by current versions of Excel. In this case, images go into a 'DSO' record (I think). Images done in this way are like any other cell content. This would be the simplest way to implement image support, and is used by some PERL programs There is also a patch to JExcelApi (but it's not part of the main distribution yet) that does the same thing. Images attached in this way have to be relatively small, and have to be a certain style of bitmap.
Here is a freshmeat description of Spreadsheet::WriteExcel http://freshmeat.net/projects/writeexcel/?topic_id=66%2C78%2C131%2C809 "The Spreadsheet::WriteExcel module can be used to create a cross-platform Excel binary file. Multiple worksheets can be added to a workbook and formatting can be applied to cells. Text, numbers, formulas, hyperlinks and images can be written to the cells" Here is a link to JExcelApi (on SourceForge) http://sourceforge.net/projects/jexcelapi/ The patch to attach images is in their Yahoo Group http://groups.yahoo.com/group/JExcelApi/ Join the group, click on 'Files', then look for jxl_2_3_11_image_patch.zip The second way is through the Escher layer. In this case, images are part of the Unknown Record ec (and eb and ed), which have the names MSODRAWINGGROUP, MSODRAWING, and MSODRAWINGSELECTION You can read my earlier messages describing this format at a high level Basically, the images themselves are stored inside the MSODRAWINGGROUP record. The position and properties such as borders, background color, grouping with other objects is described in the MSODRAWING record. And the last selected object is stored in the MSODRAWINGSELECTION record. There will also be an OBJ record for each image, which is how Excel comes up with the name 'Picture 1' when the image is selected. You can read some of my earlier posts http://www.mail-archive.com/[EMAIL PROTECTED]/msg03479.html http://www.mail-archive.com/[EMAIL PROTECTED]/msg03305.html I had developed a POI based parser for this, but stopped work when I read that the committers were going to implement Escher support 'real soon now' (That was back in October). The third way is as an OLE attachment. In this case, the images themselves go into a separate stream in the OLE Doc file. Images attached in this way are actually OLE documents, and will have an associated program such as PaintBrush, PhotoShop or some other graphics editor. The 'image' can even be a Power Point slide, a page from a Word document, or another Excel spreadsheet. This second stream is referenced by an OBJECT record -----Original Message----- From: Kais Dukes [mailto:[EMAIL PROTECTED] Sent: Thursday, January 22, 2004 7:53 AM To: POI Developers List Subject: RE: Support for Images and charting Glen, Thanks for the bar chart records, there very useful. Do you have a similar dump for images? Kind Regards -- Kais -----Original Message----- From: Glen Stampoultzis [mailto:[EMAIL PROTECTED] Sent: 22 January 2004 12:50 To: POI Developers List Subject: Re: Support for Images and charting At 04:57 PM 22/01/2004, you wrote: >I think all things left to do in HSSF are basically easy, but what do I >know. Hrrmm... charting will be a lot of work. The main problem is that there's very little information available on how charts work. These are the records for a very "simple" bar chart: [UNKNOWN RECORD:ec] [UNKNOWN RECORD:5d] [BOF RECORD] [HEADER] [FOOTER] [HCENTER] [VCENTER] [PRINTSETUP] [UNKNOWN RECORD:33] [FBI] [FBI] [PROTECT] [UNITS] [CHART] [BEGIN] [SCL] // zoom magnification [PLOTGROWTH] // font scaling [FRAME] // border around text [BEGIN] // default line and area format [LINEFORMAT] [AREAFORMAT] [END] [SERIES] // start of series [BEGIN] [AI] // LINK_TYPE_TITLE_OR_TEXT [AI] // LINK_TYPE_VALUES [AI] // LINK_TYPE_CATEGORIES [AI] // ?? [DATAFORMAT] // Formatting applies to series? [BEGIN] // ?? [UNKNOWN RECORD] [END] [SeriesToChartGroup] // Used to support > 1 chart? [END] [SHTPROPS] // Some defaults for how chart is displayed. [DEFAULTTEXT] // Describes the characteristics of the next // record [TEXT] // Details of the text that follows in the // next section [BEGIN] [UNKNOWN RECORD] // POS record... looks like I missed this one. // docs seem to indicate it's better to use // defaults... [FONTX] // index to font record. [AI] // link to text? seems to be linking to nothing [END] [DEFAULTTEXT] // contains a category type of 3 which is not // documented (sigh). [TEXT] // defines position, color etc for text on chart. [BEGIN] [UNKNOWN RECORD] // Another pos record [FONTX] // font [AI] // reference type is DIRECT (not sure what this // means) [END] [AXISUSED] // number of axis on the chart. [AXISPARENT] // axis size and location [BEGIN] // beginning of axis details [UNKNOWN RECORD] // Another pos record. [AXIS] // Category axis [BEGIN] [CATSERRANGE] // defines tick marks and other stuff [AXCEXT] // unit information [TICK] // tick formating characteristics [END] [AXIS] // Value axis [BEGIN] [VALUERANGE] // defines tick marks and other stuff [TICK] // tick formating characteristics [AXISLINEFORMAT] // major grid line axis format [LINEFORMAT] // what do the lines look like? [END] [PLOTAREA] // marks that the frame following belongs // to the frame. [FRAME] // border [BEGIN] [LINEFORMAT] // border line [AREAFORMAT] // border area [END] [CHARTFORMAT] // marks a chart group [BEGIN] [BAR] // indicates a bar chart [UNKNOWN RECORD] // apparently this record is ignoreable [LEGEND] // positioning for the legend [BEGIN] [UNKNOWN RECORD] // another position record. [TEXT] // details of the text that follows // in the next section [BEGIN] [UNKNOWN RECORD] // yet another pos record [AI] // another link (of type direct) [END] [END] [END] [END] [END] [DIMENSIONS] [SINDEX] [SINDEX] [SINDEX] [EOF] Glen [EMAIL PROTECTED] http://members.iinet.net.au/~gstamp/glen/ --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
