7 Replies Latest reply on Sep 18, 2008 2:32 PM by johnmccallum

    Growing .CHM file

    Lew at Chyron Level 1
      My .CHM continues growing at a rate disproportionate to the new material I’m adding. There are still things I don’t know about RoboHelp, but I’m pretty sure these increases add up to more than any graphics or (less likely yet) text I’m including with each new or updated Topic.

      I've tried removing "Unused Files", even though I know that such files shouldn't be getting incorporated into a finished .CHM anyway.

      Needless to say I always check "Optimize CHM File Size" on the Options dialog for my Primary Layout.

      Any help would be appreciated!
        • 1. Re: Growing .CHM file
          RoboColum(n) Level 5
          Is your Project source located on a local drive (good) or a network drive (bad). You may also want to close your project, rename the project's .CPD file and reopen the project which recreates the .CPD file. If this still doesn't solve the problem it would be worht reading this article.
          • 2. Re: Growing .CHM file
            Lew at Chyron Level 1

            Hi, Colum:

            Thanks for the reply. I'll try the .CPD experiment on a COPY of the project (no fool am I!) after I post this first reply.

            First: Thank goodness, the project is on a local drive.

            Second: Here's an experiment I tried yesterday:

            I tracked down the largest image file in my project, a .jpg whose size is 1.5 MB. I "editorially" removed the photo from the content in which it was included, saved the topic and the project and closed RoboHelp to give it the best chance of keeping its act together in terms of the database of files.

            Reopened it and generated an Unused Files report. Noted that my now-editorially-unneeded file was now duly listed as such, and removed it in Windows Explorer. Closed and reopened RH. Compiled.

            Now, finally something less boring, that poses a real question.

            With the removal of a 1.15 MB .jpg file, the .chm file was reduced from its previous size of "82, 334 kb" to "81, 224 kb" for the new, reduced-content build.

            This size reduction is about 1.1 MB, is about the size of the ONE file I removed.

            Given the compression that RoboHelp presumably performs in making a .CHM, shouldn't the DIFFERENCE in size be SMALLER after removal of this one file?

            A bit of dreary subtlety perhaps, but it leads me back to the inexplicable-seeming growth of my .CHMs even on occasions when I've definitely only added text to the project.

            An example of this is adding 400 words of text and getting scary-seeming increases of something like a whole MB.

            Hope I'm not rambling too much, but I can see this trend reaching real problem-status soon. My .CHMs are posted for download by our product's users, and even though they're presumably all in professional facilites with swell internet connections, sooner or later, I'm going to get complaints. (I've already gotten raised eyebrows.)

            • 3. Re: Growing .CHM file
              Level 2

              While a CHM file is compressed, so is a jpg so removing an already compressed file should remove approximately the same space.

              I'm not sure why your CHM is growing, but the compiler often includes files it 'thinls' you might need if they are in your project folder. This is especially a problem if you are testing links to external files as you create the CHM. It might help to scan the project folder for any large files that shouldn't be in your project.

              • 4. Growing .CHM file
                Lew at Chyron Level 1
                Hi, John:

                Good idea, but any idea what kind of file I'm looking for? And are we talking about something perhaps spuriously generated by RH, and hanging out in my Project Folder? Even if RH is wrong in thinking it needs something, might it not be disastrous to just remove the thing? Even if it's wrong, I suspect that what RoboHelp THINKS about the state of things is still the bottom line. Kind of like in the media, where whatever "sticks" is all that matters, true or not. (That was non-partisan, I swear!)

                Mind you, I have removed officially "Report"-ed Unused Files before. Matter of fact, I've run two reports on two successive days, and had RH report more unneeded files after I scrupulously deleted everything in the previous report. This, without making any editorial changes.

                Wonderful as this tool is, RoboHelp worries me a little.

                Also, renaming the existing CPD to make it...inert, and thus generating a new one, has yielded a .CHM size decrease of only 75 KB.

                The old CPD was 4,092 KB and the new one is 1, 420 KB.
                • 5. Re: Growing .CHM file
                  Level 2

                  Some of the things that might cause a CHM file to bloat are things like PDFs that are brought into your folder for testing but are intended to be external links in the final product. If you don't have any thing like that, there could be some extra unwanted files.

                  I once renamed a CHM using Windows Explorer and the compiler included that CHM in the next compile. It wasn't in baggage and it wasn't listed in my .hhp file but nevertheless the compiler thought I might need it. To really find out what is in your CHM, you would need to decompile it. Then you can spot any big files that shouldn't be there. I'd just scan through the sizes or look for duplicate files.

                  • 6. Re: Growing .CHM file
                    MergeThis Level 4
                    John's thoughts on residual files could be spot on. The other thing is: RH might not be the culprit you think it is, since I believe RH simply uses the Microsoft HH compiler, and not its own.

                    Have you tried compiling to an entirely different pathname\filename (C:\OtherPath\OtherFileName.chm)? That might break the cycle. Just create a new Printed Doc layout for this new output and give it a shot. You might also try compiling it with the MS Html Help Workshop, if it's installed on your machine.

                    Good luck,
                    • 7. Re: Growing .CHM file
                      Level 2

                      As far as I know RoboHelp does use the microsoft compiler, so compiling with HelpWorkshop would lead to the same problems. That said, RH and HelpWorkshop do give slightly different CHM outputs, though I have never taken the time to figure out what they do differently. I just know that they are always a few bytes different in size.

                      I don't know much about the latest versions of RoboHelp and the single source files. There is probably all kinds of new stuff that the compiler might include. The compiler hasn't been updated in approximately forever, so it may balk at some of the upgrades to RH. I wouldn't know - my version is probably from the last millenium. It did come with a decompiler - called "HTMLHelp studio" back then. I assume the latest version has something similar. If not, HelpWorkshop can also decompile. That is probably the only surefire way to know what is getting into your CHM.