FileFormatHandler Manual
The maxon::FileFormatHandlerInterface provides functionality to access files of a given type. It is typically used to create specific handlers using CreateHandler().
The FileFormatHandler for a given file is typically obtained with maxon::FileFormatDetectionInterface::Detect() .
The maxon::FileFormatHandlerInterface provides these functions:
The following maxon::FileFormatHandler implementations are registered at the maxon::FileFormatHandlers registry and are accessible at these published objects:
Archive files. See also Archives Manual .
// create ReadArchiveRef handler for a ZIP file const maxon::FileFormatHandler& handler = maxon::FileFormatHandlers::ZipArchiveHandler(); const maxon::ReadArchiveRef zipArchive = handler.CreateHandler<maxon::ReadArchiveRef>( maxon::Url ()) iferr_return ;
// open ZIP file zipArchive.Open(zipFile) iferr_return ;
// extract all files to the given target folder const maxon::IOARCHIVEEXTRACTFLAGS flags = maxon::IOARCHIVEEXTRACTFLAGS::OVERWRITE_EXISTING_FILE ; zipArchive.Extract(targetFolder, maxon::ThreadRef (), flags, nullptr ) iferr_return ;
// close ZIP file zipArchive.Close() iferr_return ;
These handlers access image and video files and return a maxon::MediaInputRef. See Images Manual and Media Sessions Manual .
Audio files are handled with these handler which also return a maxon::MediaInputRef:
//---------------------------------------------------------------------------------------- // Loads the image at the given URL. // @param[in] url The URL of the image file. // @param[out] targetTexture The ImageTextureRef to load the image into. // @return OK on success. //---------------------------------------------------------------------------------------- static maxon::Result<void> LoadImageFromUrl( const maxon::Url & url, maxon::ImageTextureRef& targetTexture) { iferr_scope ;
// define source const maxon::FileFormatHandler importFileFormat = maxon::FileFormatDetectionInterface::Detect<maxon::MediaInputRef>(url) iferr_return ; const maxon::MediaInputRef source = importFileFormat.CreateHandler<maxon::MediaInputRef>(url) iferr_return ;
// define destination const maxon::MediaOutputTextureRef destination = maxon::MediaOutputTextureClass().Create() iferr_return ; destination.SetOutputTexture(targetTexture, maxon::ImagePixelStorageClasses::Normal()) iferr_return ;
// convert const maxon::MediaSessionRef session = maxon::MediaSessionObject().Create() iferr_return ; session.ConnectMediaConverter(source, destination) iferr_return ; session.Convert( maxon::TimeValue (), maxon::MEDIASESSIONFLAGS::NONE ) iferr_return ; session.Close() iferr_return ; return maxon::OK ; }
// This example function loads an image sequence found in the given folder. // The images are loaded in the prepared ImageRef array.
//---------------------------------------------------------------------------------------- // Loads the image sequence found in the given folder. // @param[in] folder Folder containing an image sequence in the format "sequence_00.png". // @param[out] images Array with pre-allocated images to load the image data into. // @return OK on success. //---------------------------------------------------------------------------------------- static maxon::Result<void> LoadImageSequence( const maxon::Url & folder, maxon::BaseArray<maxon::ImageRef> & images) { iferr_scope ; if (folder.IsEmpty() || images. IsEmpty ()) return maxon::IllegalArgumentError( MAXON_SOURCE_LOCATION );
// load only as many images as the ImageRef array can hold const maxon::Int firstFrame = 0; const maxon::Int lastFrame = images. GetCount () - 1; const maxon::Float fps = 25.0_f;
// define source const maxon::String filename { "sequence_" }; maxon::Url sequenceURL = (folder + maxon::Url (filename)) iferr_return ; maxon::String name = sequenceURL.GetName(); // between "{" and "}" the number format is defined as used with FormatString(). // the file name format is sequence_00.png, sequence_01.png, ... name += "@{2'0'}.png" _s; sequenceURL.SetName(name) iferr_return ; sequenceURL. Set (maxon::URLFLAGS::IMAGESEQUENCE_FPS, fps) iferr_return ; sequenceURL. Set (maxon::URLFLAGS::IMAGESEQUENCE_FIRSTFRAME, firstFrame) iferr_return ; sequenceURL. Set (maxon::URLFLAGS::IMAGESEQUENCE_LASTFRAME, lastFrame) iferr_return ; const maxon::FileFormatHandler imageSequence = maxon::FileFormatHandlers::MovieImageSequence(); const maxon::MediaInputRef source = imageSequence.CreateHandler<maxon::MediaInputRef>(sequenceURL) iferr_return ;
// define destination const maxon::ImageTextureRef texture = maxon::ImageTextureClasses::TEXTURE().Create() iferr_return ; const maxon::MediaOutputTextureRef destination = maxon::MediaOutputTextureClass().Create() iferr_return ; destination.SetOutputTexture(texture, maxon::ImagePixelStorageClasses::Normal()) iferr_return ;
// convert const maxon::MediaSessionRef session = maxon::MediaSessionObject().Create() iferr_return ; session.ConnectMediaConverter(source, destination) iferr_return ;
// fps maxon::TimeValue frameDuration; frameDuration. SetSeconds (1.0 / fps); maxon::TimeValue currentTime;
// load each frame for ( maxon::Int frame = 0; frame <= lastFrame; ++frame) { // load frame session.Convert(currentTime, maxon::MEDIASESSIONFLAGS::NONE ) iferr_return ; // get image const maxon::ImageRef image = maxon::GetImageOf (texture); // copy image to target array images[frame] = image.Clone() iferr_return ; currentTime += frameDuration; } return session.Close(); }
