Mac Forum / Programming / Mac Programming / June 2006

Thanks Reinder. The link you provided is broken for me, but I'll find
it.

I think the call QuickTime and iMovie use is QTExportSessionShowUI(),
but it's undocumented and I've no idea what parameters it takes. (I
know using an undocumented call is a bit risky, but it's for an
internal tool in this case, so that's not a problem).

Thanks for that Michael, the batch export is what I need. The export
dialog it uses is slightly different from that in Quicktime Player and
iMovie, but it has the 'Movie Settings' window which is perfect.

I saw you're using MovieExportDoUserDialog, and realised I was using
the right function, but on the wrong component. I was specifying 'hint'
as the component manufacturer, instead of kAppleManufacturer.

Unfortunately, it's crashing on MovieExportDoUserDialog. Here's the
code from QTHintMovies, edited only to change the component
manufacturer, and to use paths instead of FSSpecs.

    ComponentDescription        myCompDesc;
    MovieExportComponent        myExporter = NULL;
    long                        myFlags = createMovieFileDeleteCurFile | movieFileSpecValid;
    ComponentResult                myErr = badComponentType;
    Boolean        myCancelled = false;

    // find and open a movie export component that can hint a movie file
    myCompDesc.componentType = MovieExportType;
    myCompDesc.componentSubType = MovieFileType;
    myCompDesc.componentManufacturer = kAppleManufacturer
;//FOUR_CHAR_CODE('hint');
    myCompDesc.componentFlags = 0;
    myCompDesc.componentFlagsMask = 0;
    myExporter = OpenComponent(FindNextComponent(NULL, &myCompDesc));
    if (myExporter == NULL)
        goto bail;

    // use the default progress procedure
    SetMovieProgressProc(theMovie, (MovieProgressUPP)-1L, 0);

    // get the preferences file for this application
    NSString*    prefsFilePath = nil;
    prefsFilePath = QTHints_GetPrefsFilePath(moviePath) ;

    // read existing movie exporter settings from a file; if we aren't
going to prompt
    // the user for exporter settings, these stored settings will be used;
otherwise,
    // these stored settings will be used as initial values in the
settings dialog box
    QTUtils_GetExporterSettingsFromFile(myExporter, prefsFilePath);

    if (thePromptUser) {

        // display a dialog box to prompt the user for desired movie exporter
settings
        myErr = MovieExportDoUserDialog(myExporter, theMovie, NULL, 0, 0,
&myCancelled);
        if (myCancelled)
            goto bail;
        // save the existing settings into our preferences file
        QTUtils_SaveExporterSettingsInFile(myExporter, prefsFilePath);
    }

    if (!myCancelled)
    {
        Handle        dataReference = nil ;
        OSType        dataReferenceType ;
        myErr = QTNewDataReferenceFromFullPathCFString(
(CFStringRef)moviePath,
kQTNativeDefaultPathStyle,0,&dataReference,&dataReferenceType) ;

        myErr = ConvertMovieToDataRef(    theMovie,
                                        NULL,
                                        dataReference,
                                        dataReferenceType,
                                        MovieFileType,FOUR_CHAR_CODE('TVOD'),
                                        myFlags,
                                        myExporter) ;       
    }

Unfortunately, it's not really suitable. If QTAmateur encounters a
movie it can't open (some of the source movies provided to me may be
invalid), the batch export will stop and can't be restarted - there's
no option to skip or remove a movie from the batch. The app also
crashed after a hundred movies or so (quite possibly caused by an
invalid movie).

Also, it's not apparent how the movies are sorted in the batch, hence
if a batch stops for any reason, it's very difficult to determine from
which point to resume.

If you could provide a code snippet for the movie export - or a link to
relevant Apple sample - I'd really appreciate it!

Thanks for your help,
Mike.