Q: My application calls the GetDIBFromPict function, and this works fine provided QuickTime was installed on the machine using the "Recommended" installation option. However, if the user instead chose the "Minimum" installation option the GetDIBFromPict function always returns zero, and sometimes a QuickTime dialog pops up telling me additional software is required. I need to know ahead of time whether or not the GetDIBFromPict function is going to fail. Is this possible?A: You can't check for the various QuickTime installations ("Minimal", "Recommended" and so on). However, you can check for the presence of any of the QuickTime components required by a given function such as GetDIBFromPict or by a given QuickTime movie. For example, GetDIBFromPict requires the QuickTime BMP movie export component. You can check for this component using the Component Manager FindNextComponent function as shown below: Listing 1: Checking for the presence of the BMP movie exporter component.
#include <QuickTimeComponents.h>
Boolean isBMPExporterAvailable()
{
ComponentDescription cd;
Component aComponent = 0;
cd.componentType = MovieExportType;
cd.componentSubType = kQTFileTypeBMP;
cd.componentManufacturer = 0;
cd.componentFlags = 0;
cd.componentFlagsMask = cmpIsMissing;
aComponent = FindNextComponent( 0, &cd ) ;
return (aComponent != 0);
}
Technical Q&A QA1093, 'Determining required components for QuickTime movies' describes techniques for determining which components are required for a given movie. Finally, you can disable any error dialog from appearing if the necessary components are not present on the user's machine. See Technical Q&A QA1164, 'Disabling QuickTime Error Dialogs When Opening or Tasking a Movie'. Document Revision History| Date | Notes |
|---|
| 2004-09-28 | Demonstrates how to check for any available QuickTime components required by individual QuickTime functions. |
Posted: 2004-09-28
| 