NAME

blob - Methods to Read or Write Binary Large OBjects


SYNOPSIS

void AttachBlob( BlobInfo *blob_info, const void *blob, const size_t length );

unsigned int BlobToFile( const char *filename, const void *blob, const size_t length, ExceptionInfo *exception );

Image * BlobToImage( const ImageInfo *image_info, const void *blob, const size_t length, ExceptionInfo *exception );

BlobInfo * CloneBlobInfo( const BlobInfo *blob_info );

void DestroyBlobInfo( BlobInfo *blob );

void DetachBlob( BlobInfo *blob_info );

void * FileToBlob( const char *filename, size_t *length, ExceptionInfo *exception );

void GetBlobInfo( BlobInfo *blob_info );

void * ImageToBlob( const ImageInfo *image_info, Image *image, size_t *length, ExceptionInfo *exception );

Image * PingBlob( const ImageInfo *image_info, const void *blob, const size_t length, ExceptionInfo *exception );

BlobInfo ReferenceBlob( BlobInfo *blob_info );


FUNCTION DESCRIPTIONS

AttachBlob

Method AttachBlob attaches a blob to the BlobInfo structure.

The format of the AttachBlob method is:

void AttachBlob ( BlobInfo *blob_info, const void *blob, const size_t length );

A description of each parameter follows:

blob_info:
Specifies a pointer to a BlobInfo structure.

blob:
The address of a character stream in one of the image formats understood by ImageMagick.

length:
This size_t integer reflects the length in bytes of the blob.

BlobToFile

BlobToFile() writes a blob to a file. It returns False if an error occurs otherwise True.

The format of the BlobToFile method is:

unsigned int BlobToFile ( const char *filename, const void *blob, const size_t length, ExceptionInfo *exception );

A description of each parameter follows:

status:
BlobToFile returns True on success; otherwise, it returns False if an error occurs.

filename:
Write the blob to this file.

blob:
The address of a blob.

length:
This length in bytes of the blob.

BlobToImage

BlobToImage() implements direct to memory image formats. It returns the blob as an image.

The format of the BlobToImage method is:

Image *BlobToImage ( const ImageInfo *image_info, const void *blob, const size_t length, ExceptionInfo *exception );

A description of each parameter follows:

image_info:
The image info.

blob:
The address of a character stream in one of the image formats understood by ImageMagick.

length:
This size_t integer reflects the length in bytes of the blob.

exception:
Return any errors or warnings in this structure.

CloneBlobInfo

Method CloneBlobInfo makes a duplicate of the given blob info structure, or if blob info is NULL, a new one.

The format of the CloneBlobInfo method is:

BlobInfo *CloneBlobInfo ( const BlobInfo *blob_info );

A description of each parameter follows:

clone_info:
Method CloneBlobInfo returns a duplicate of the given blob info, or if blob info is NULL a new one.

quantize_info:
a structure of type info.

DestroyBlobInfo

DestroyBlobInfo() deallocates memory associated with an BlobInfo structure.

The format of the DestroyBlobInfo method is:

void DestroyBlobInfo ( BlobInfo *blob );

A description of each parameter follows:

blob:
Specifies a pointer to a BlobInfo structure.

DetachBlob

Method DetachBlob detaches a blob from the BlobInfo structure.

The format of the DetachBlob method is:

void DetachBlob ( BlobInfo *blob_info );

A description of each parameter follows:

blob_info:
Specifies a pointer to a BlobInfo structure.

FileToBlob

FileToBlob() returns the contents of a file as a blob. It returns the file as a blob and its length. If an error occurs, NULL is returned.

The format of the FileToBlob method is:

void *FileToBlob ( const char *filename, size_t *length, ExceptionInfo *exception );

A description of each parameter follows:

blob:
FileToBlob() returns the contents of a file as a blob. If an error occurs NULL is returned.

filename:
The filename.

length:
This pointer to a size_t integer sets the initial length of the blob. On return, it reflects the actual length of the blob.

exception:
Return any errors or warnings in this structure.

GetBlobInfo

GetBlobInfo() initializes the BlobInfo structure.

The format of the GetBlobInfo method is:

void GetBlobInfo ( BlobInfo *blob_info );

A description of each parameter follows:

blob_info:
Specifies a pointer to a BlobInfo structure.

ImageToBlob

ImageToBlob() implements direct to memory image formats. It returns the image as a blob and its length. The magick member of the Image structure determines the format of the returned blob ( GIG, JPEG, PNG, etc. )

The format of the ImageToBlob method is:

void *ImageToBlob ( const ImageInfo *image_info, Image *image, size_t *length, ExceptionInfo *exception );

A description of each parameter follows:

image_info:
The image info..

image:
The image.

length:
This pointer to a size_t integer sets the initial length of the blob. On return, it reflects the actual length of the blob.

exception:
Return any errors or warnings in this structure.

PingBlob

PingBlob() returns all the attributes of an image or image sequence except for the pixels. It is much faster and consumes far less memory than BlobToImage ( ) . On failure, a NULL image is returned and exception describes the reason for the failure.

The format of the PingBlob method is:

Image *PingBlob ( const ImageInfo *image_info, const void *blob, const size_t length, ExceptionInfo *exception );

A description of each parameter follows:

image_info:
The image info.

blob:
The address of a character stream in one of the image formats understood by ImageMagick.

length:
This size_t integer reflects the length in bytes of the blob.

exception:
Return any errors or warnings in this structure.

ReferenceBlob

ReferenceBlob() increments the reference count associated with the pixel blob returning a pointer to the blob.

The format of the ReferenceBlob method is:

BlobInfo ReferenceBlob ( BlobInfo *blob_info );

A description of each parameter follows:

blob_info:
The blob_info.