SoRasterImageRW Class Reference
[Image]
Abstract base class for encoding and decoding raster images.
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#include <Inventor/image/SoRasterImageRW.h>
Detailed Description
Abstract base class for encoding and decoding raster images.
SoRasterImageRW is the base class used for encoding and decoding raster images.
The following file formats are supported for raster image input (i.e., read):
- BMP (Windows only)
- DDS
- GIF
- HDRI (with SoTextureCubeMap only)
- JPEG 2000
- JPEG
- PGX
- PNG
- PNM
- SGI RGBA
- Sun
- TIFF
The following formats are supported for raster image output (i.e., write):
- All the above except GIF (read only), plus
- PS (PostScript), which is available for writing only.
Note that only the following image file formats can contain transparency (alpha channel) information:
- DDS
- GIF
- PNG
- SGI RGBA
- TIFF
There is a subclass of SoRasterImageRW for each of the above formats.
The convenience class SoRasterReaderSet can be used to determine the appropriate reader class for an image file by attempting to read the file using each of the built-in reader classes.
A subclass of SoRasterImageIO, e.g. SoRasterImageFile, must be used as the source of a read operation or the destination of a write operation.
Note that it is not necessary to explicitly load image files for common operations like texture mapping. SoTexture2, for example, automatically loads the image file specified in its filename field.
SoRasterImageRW classes support two methods of writing out an image. The simplest one is writing out a complete image already assembled in memory. This is the default method and is efficiently supported by all image formats. SoRasterImageRW also supports assembling an image from multiple sub-images or "tiles". The SoOffscreenRenderer class, for example, uses this feature when the requested image size is too large for OpenGL to render as a single image. To use this feature call the enableMultipleWriting method with TRUE. Note that some image formats allow the image to be written (encoded) incrementally, so tiles provided in scan-line order can written immediately, with no intermediate storage. Other image formats cannot be encoded until the complete image is assembled in memory.
Image formats that allow tiles to be written incrementally have the writeCapability WRITE_SCANLINES. This is the most memory efficient way to write large images. Note that some image formats are encoded from top to bottom and some are encoded from bottom to top. The method isMultipleBufferInverted returns TRUE if the format should be encoded from bottom to top.
Image formats that require a complete image before encoding have the writeCapability WRITE_FULL_IMAGE. In this case the SoRasterImageRW subclass will automatically allocate enough memory to hold the complete image. This may require a very large block of contiguous memory! The image is not actually written until the writeFooter method is called.
EXAMPLE
- Load an image from a PNG format file (error checking is omitted for clarity):
SoRasterImageFile inputFile( "test.png" ); SoPNGImageRW imageReader; imageReader.open( &inputFile, SoRasterImageRW::OPEN_READ ); SbRasterImage image; imageReader.read( &image ); imageReader.close();
EXAMPLE
- Write an image to a JPEG format file (error checking is omitted for clarity):
SoRasterImageFile outputFile( "test.jpg" ); SoJPEGImageRW imageWriter; imageWriter.open( &outputFile, SoRasterImageRW::OPEN_WRITE ); SbRasterImage image . . .; // Previously created SbVec2i32 size = image.getSize_i32(); imageWriter.writeHeader( size ); imageWriter.write( &image ); imageWriter.writeFooter(); imageWriter.close();
SEE ALSO
SoBMPImageRW, SoDDSImageRW, SoGIFImageRW, SoJP2ImageRW, SoJPEGImageRW, SoPGXImageRW, SoPNGImageRW, SoPNMImageRW, SoPSImageRW, SoSGIRGBImageRW, SoSUNImageRW, SoTIFFImageRW, SoRasterReaderSet
- See related examples:
Member Enumeration Documentation
Constructor & Destructor Documentation
| virtual SoRasterImageRW::~SoRasterImageRW | ( | ) | [virtual] |
Destructor.
Member Function Documentation
| virtual SbBool SoRasterImageRW::checkRead | ( | SoRasterImageFile * | imageFile | ) | [virtual] |
Checks if the specified file can be read.
Returns true if successful.
| virtual void SoRasterImageRW::close | ( | ) | [virtual] |
Closes the reader/writer.
Reimplemented in SoBMPImageRW, and SoJPEGImageRW.
| virtual void SoRasterImageRW::enableMultipleWriting | ( | SbBool | state | ) | [virtual] |
Enable writing image with multiple calls to write method.
Default is FALSE.
| static SoType SoRasterImageRW::getClassTypeId | ( | ) | [static] |
Returns the type identifier for this class.
Reimplemented in SoBMPImageRW, SoDDSImageRW, SoGIFImageRW, SoHDRImageRW, SoJP2ImageRW, SoJPEGImageRW, SoPGXImageRW, SoPNGImageRW, SoPNMImageRW, SoPSImageRW, SoSGIRGBImageRW, SoSUNImageRW, and SoTIFFImageRW.
| virtual SoRasterImageRW::ReadCapability SoRasterImageRW::getReadCapability | ( | ) | const [virtual] |
Returns the read capability of the raster format.
Returns READ_AVAILABLE by default.
Reimplemented in SoBMPImageRW, SoDDSImageRW, SoGIFImageRW, SoHDRImageRW, SoJP2ImageRW, SoJPEGImageRW, SoPGXImageRW, SoPNGImageRW, SoPNMImageRW, SoPSImageRW, SoSGIRGBImageRW, and SoSUNImageRW.
| virtual SbString* SoRasterImageRW::getSuffixes | ( | int & | numSuffixes | ) | const [virtual] |
Returns the list of file suffixes supported.
Return value is a pointer to an array containing numSuffixes SbString objects. This is internal object memory. Do NOT delete or modify.
| virtual SoType SoRasterImageRW::getTypeId | ( | ) | const [pure virtual] |
Returns the type identifier for this specific instance.
Implemented in SoBMPImageRW, SoDDSImageRW, SoGIFImageRW, SoHDRImageRW, SoJP2ImageRW, SoJPEGImageRW, SoPGXImageRW, SoPNGImageRW, SoPNMImageRW, SoPSImageRW, SoSGIRGBImageRW, SoSUNImageRW, and SoTIFFImageRW.
| virtual SoRasterImageRW::WriteCapability SoRasterImageRW::getWriteCapability | ( | ) | const [virtual] |
Returns the write capability of the raster format.
Returns WRITE_SCANLINES by default.
Reimplemented in SoBMPImageRW, SoDDSImageRW, SoGIFImageRW, SoHDRImageRW, SoJP2ImageRW, SoJPEGImageRW, SoPGXImageRW, SoPNGImageRW, SoPNMImageRW, SoPSImageRW, SoSGIRGBImageRW, and SoSUNImageRW.
| virtual SbBool SoRasterImageRW::isMultipleBufferInverted | ( | ) | const [virtual] |
Returns the write order when using multiple buffers.
Returns FALSE if buffers are written from top to bottom. Returns TRUE if buffers are written from bottom to top. Returns TRUE by default.
Reimplemented in SoBMPImageRW, SoDDSImageRW, SoGIFImageRW, SoHDRImageRW, SoJP2ImageRW, SoJPEGImageRW, SoPGXImageRW, SoPNGImageRW, SoPNMImageRW, SoPSImageRW, SoSGIRGBImageRW, and SoSUNImageRW.
| virtual SbBool SoRasterImageRW::isMultipleWritingEnabled | ( | ) | const [virtual] |
Returns TRUE if multiple buffer writing is enabled.
| virtual SbBool SoRasterImageRW::open | ( | SoRasterImageIO * | rasterImageIO, | |
| OpenMode | openMode | |||
| ) | [virtual] |
Opens the reader/writer in the specified open mode.
Returns true if successful.
Reimplemented in SoBMPImageRW, SoDDSImageRW, SoGIFImageRW, SoHDRImageRW, SoJP2ImageRW, SoJPEGImageRW, SoPGXImageRW, SoPNGImageRW, SoPNMImageRW, SoSGIRGBImageRW, SoSUNImageRW, and SoTIFFImageRW.
| virtual SbBool SoRasterImageRW::read | ( | SbRasterImage * | rasterImage, | |
| SbBool | infoOnly = FALSE | |||
| ) | [pure virtual] |
Read the current open image into rasterImage.
Returns true if successful. Call the open() method before calling this method.
If infoOnly is TRUE, then the buffer will not be read; the parameter rasterImage will be set with raster size and raster number of components, the buffer will be NULL.
Implemented in SoBMPImageRW, SoDDSImageRW, SoGIFImageRW, SoHDRImageRW, SoJP2ImageRW, SoJPEGImageRW, SoPGXImageRW, SoPNGImageRW, SoPNMImageRW, SoPSImageRW, SoSGIRGBImageRW, SoSUNImageRW, and SoTIFFImageRW.
| virtual SbBool SoRasterImageRW::readRegion | ( | SbRasterImage * | rasterImage, | |
| const SbBox2i32 & | region | |||
| ) | [virtual] |
Read the specified region of current open image into rasterImage.
Returns true if successful. Call the open() method before calling this method.
After calling this method successfully, the size of the SbRasterImage is the requested region size. The requested region may extend outside the source image. In this case, undefined pixels are set to zero. The region may be as small as a single pixel, e.g. (1,1,1,1), but xmin must be <= xmax and ymin <= ymax.
Reimplemented in SoJP2ImageRW, and SoTIFFImageRW.
| virtual SbBool SoRasterImageRW::write | ( | SbRasterImage * | rasterImage, | |
| unsigned int | xPos = 0, |
|||
| unsigned int | yPos = 0 | |||
| ) | [pure virtual] |
Writes and encodes the given data in the specific format.
Returns true if successful. If you are using the multiple writing mode, then you can give the offset with (xPos,yPos) you want to write to.
Implemented in SoBMPImageRW, SoDDSImageRW, SoGIFImageRW, SoHDRImageRW, SoJP2ImageRW, SoJPEGImageRW, SoPGXImageRW, SoPNGImageRW, SoPNMImageRW, SoPSImageRW, SoSGIRGBImageRW, SoSUNImageRW, and SoTIFFImageRW.
| virtual SbBool SoRasterImageRW::writeFooter | ( | ) | [virtual] |
Writes and encodes the footer for this specific format.
Returns true if successful.
Reimplemented in SoBMPImageRW, SoHDRImageRW, SoJPEGImageRW, SoPSImageRW, and SoSGIRGBImageRW.
Writes and encodes the header for this specific format.
Returns true if successful. The parameter is the size of the whole raster image to be saved. The size is limited to 32767 by 32767
- Deprecated:
-
Deprecated since Open Inventor 8000
Use writeHeader(SbVec2i32& size) instead.
Writes and encodes the header for this specific format.
Returns true if successful. The parameter is the size of the whole raster image to be saved. Use for sizes with at least one side greater than 32767.
- Deprecated:
-
Deprecated since Open Inventor 9700
Use writeHeader(const SbVec2i32& size) instead.
Writes and encodes the header for this specific format.
Returns true if successful. The parameter is the size of the whole raster image to be saved. Use for sizes with at least one side greater than 32767.
The documentation for this class was generated from the following file:
- Inventor/image/SoRasterImageRW.h