Automatically Slicing Large TIFF Files with Photoshop 5.1

Question

I am trying to automatically slice a very large TIFF file (800 MB) into 28 equally-sized rectangles using Actions (it is a scanned image of 28 scientific slides and reducing the resolution is not an option). My goal is to start with the TIFF file and end up with a folder that contains 28 separate files. I'll do this on many such TIFF files, so it needs to be coded into an action.
So far I have an action that creates guides in a grid pattern and then converts the guides to 28 individual rectangular user slices that together cover the entire screen. Unfortunately the file is far too large  to use with the "Save for Web & Devices" tool and I also can't export to TIFF from that tool. So I made an action that individually selects each slice (using the slice select tool), copies it, creates a new file, pastes the image, saves it as a flattened, non-compressed TIFF into a new folder, then closes the file. When I try to run this I get the following error:
The command "Select" is not currently available
          -- Continue --       -- Stop --
If I press Continue the action is not carried out. If I press Stop and select the slice manually there is no problem (but then my action will not be fully automated). The image is in 8-bit RGB mode, and I've also tried converting the locked Background layer into a standard layer. I don't see any reason why the select command shouldn't be available! There is only one layer and there are user slices available for selection. I tried separating the slicing and select/import jobs into 2 different actions but it still didn't work.
Any help you can give me would be greatly appreciated! Thank you!
Photoshop CS 5.1 Extended, v. 12.1 x64 - I have installed the recent update
Windows 7 64-bit
6 GB RAM

Answer 1

This might do it...
It will save the individual files in a folder called filechop off the files path.
#target photoshop
function main(){
if(!documents.length) return;
var dlg=
"dialog{text:'Script Interface',bounds:[100,100,380,290],"+
"panel0:Panel{bounds:[10,10,270,180] , text:'' ,properties:{borderStyle:'etched',su1PanelCoordinates:true},"+
"title:StaticText{bounds:[60,10,220,40] , text:'File Chop' ,properties:{scrolling:undefined,multiline:undefined}},"+
"panel1:Panel{bounds:[10,40,250,130] , text:'' ,properties:{borderStyle:'etched',su1PanelCoordinates:true},"+
"statictext1:StaticText{bounds:[10,10,111,30] , text:'Accross' ,properties:{scrolling:undefined,multiline:undefined}},"+
"statictext2:StaticText{bounds:[140,10,230,27] , text:'Down' ,properties:{scrolling:undefined,multiline:undefined}},"+
"across:DropDownList{bounds:[10,30,100,50]},"+
"down:DropDownList{bounds:[140,30,230,50]},"+
"saveFiles:Checkbox{bounds:[10,60,230,80] , text:'Save and Close new files?'}},"+
"button0:Button{bounds:[10,140,110,160] , text:'Ok' },"+
"button1:Button{bounds:[150,140,250,160] , text:'Cancel' }}};"
var win = new Window(dlg,'File Chop');
if(version.substr(0,version.indexOf('.'))>9){
win.panel0.title.graphics.font = ScriptUI.newFont("Georgia","BOLD",20);
g = win.graphics;
var myBrush = g.newBrush(g.BrushType.SOLID_COLOR, [1.00, 1.00, 1.00, 1]);
g.backgroundColor = myBrush;
var myPen =g.newPen (g.PenType.SOLID_COLOR, [1.00, 0.00, 0.00, 1],lineWidth=1);
win.center();
  for(var i=1;i<31;i++){
   win.panel0.panel1.across.add ('item', i);    
   win.panel0.panel1.down.add ('item', i);    
win.panel0.panel1.across.selection=0;
win.panel0.panel1.down.selection=0;
var done = false;
    while (!done) {
      var x = win.show();
      if (x == 0 || x == 2) {
        win.canceled = true;
        done = true;
      } else if (x == 1) {
        done = true;
if(!documents.length)return;
var startRulerUnits = preferences.rulerUnits;
preferences.rulerUnits = Units.PIXELS;
doc = app.activeDocument;
app.displayDialogs = DialogModes.NO;
doc.flatten();
var tilesAcross = parseInt(win.panel0.panel1.across.selection.index)+1;
var tilesDown =parseInt(win.panel0.panel1.down.selection.index)+1;
var tileWidth = parseInt(doc.width/tilesAcross);
var tileHeight = parseInt(doc.height/tilesDown);
var SaveFiles = win.panel0.panel1.saveFiles.value;
ProcessFiles(tilesDown,tilesAcross,tileWidth,tileHeight,SaveFiles);
app.preferences.rulerUnits = startRulerUnits;     
main();
function ProcessFiles(Down,Across,offsetX,offsetY,SaveFiles){
try{
var newName = activeDocument.name.match(/(.*)\.[^\.]+$/)[1];
}catch(e){var newName="UntitledChop"}
var Path='';
try{
Path =  activeDocument.path;
}catch(e){Path = "~/Desktop";}
if(SaveFiles){
Path = Folder(decodeURI(Path) +"/FileChop");
if(!Path.exists) Path.create();
TLX = 0; TLY = 0; TRX = offsetX; TRY = 0;
BRX = offsetX; BRY = offsetY; BLX = 0; BLY = offsetY;
for(var a = 0; a < Down; a++){
  for(var i = 0;i <Across; i++){
            var NewFileName = newName +"#"+a+"-"+i;
   app.activeDocument.duplicate (NewFileName, true);
    activeDocument.selection.select([[TLX,TLY],[TRX,TRY],[BRX,BRY],[BLX,BLY]], SelectionType.REPLACE, 0, false);
    executeAction( charIDToTypeID( "Crop" ), undefined, DialogModes.NO );
    app.activeDocument.selection.deselect();
if(SaveFiles){
var saveFile = File(decodeURI(Path+"/"+NewFileName+".jpg"));
SaveJPEG(saveFile, 10);
app.activeDocument.close(SaveOptions.DONOTSAVECHANGES);
    activeDocument = documents[0];
TLX = offsetX * (i+1) ; TRX  = TLX + offsetX; BRX = TRX; BLX = TLX; 
TLX = 0; TLY = offsetY * (a +1); TRX = offsetX; TRY = offsetY * (a +1);
BRX = offsetX; BRY = TRY + offsetY; BLX = 0; BLY = (offsetY * (a +1)+offsetY);
if(SaveFiles){
Path.execute()
function SaveJPEG(saveFile, jpegQuality){
jpgSaveOptions = new JPEGSaveOptions();
jpgSaveOptions.embedColorProfile = true;
jpgSaveOptions.formatOptions = FormatOptions.STANDARDBASELINE;
jpgSaveOptions.matte = MatteType.NONE;
jpgSaveOptions.quality = jpegQuality;
activeDocument.saveAs(saveFile, jpgSaveOptions, true,Extension.LOWERCASE);