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[ BlobToFile | BlobToImage | DestroyBlob | DetachBlob | FileToBlob | GetBlobError | GetBlobFileHandle | GetBlobInfo | GetBlobStreamData | GetBlobStreamHandler | ImageToBlob | ImageToFile | ImagesToBlob | IsBlobExempt | IsBlobSeekable | IsBlobTemporary | PingBlob | ReadBlobStream | SetBlobExempt ]

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

The format of the BlobToFile method is:

   MagickBooleanType BlobToFile(char *filename,const void *blob,
    const size_t length,ExceptionInfo *exception)

A description of each parameter follows:

filename

Write the blob to this file.

blob

The address of a blob.

length

This length in bytes of the blob.

exception

Return any errors or warnings in this structure.

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.

DestroyBlob() deallocates memory associated with a blob.

The format of the DestroyBlob method is:

  void DestroyBlob(Image *image)

A description of each parameter follows:

image

The image.

DetachBlob() detaches a blob from the BlobInfo structure.

The format of the DetachBlob method is:

  unsigned char *DetachBlob(BlobInfo *blob_info)

A description of each parameter follows:

blob_info

Specifies a pointer to a BlobInfo structure.

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:

  unsigned char *FileToBlob(const char *filename,const size_t extent,
    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.

extent

The maximum length of the blob.

length

On return, this reflects the actual length of the blob.

exception

Return any errors or warnings in this structure.

GetBlobError() returns MagickTrue if the blob associated with the specified image encountered an error.

The format of the GetBlobError method is:

   MagickBooleanType GetBlobError(const Image *image)

A description of each parameter follows:

image

The image.

GetBlobFileHandle() returns the file handleassociated with the image blob.

The format of the GetBlobFile method is:

  FILE *GetBlobFileHandle(const Image *image)

A description of each parameter follows:

image

The image.

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.

GetBlobStreamData() returns the stream data for the image.

The format of the GetBlobStreamData method is:

  unsigned char *GetBlobStreamData(const Image *image)

A description of each parameter follows:

image

The image.

GetBlobStreamHandler() returns the stream handler for the image.

The format of the GetBlobStreamHandler method is:

  StreamHandler GetBlobStreamHandler(const Image *image)

A description of each parameter follows:

image

The image.

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

The format of the ImageToBlob method is:

  unsigned char *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.

ImageToFile() writes an image to a file. It returns MagickFalse if an error occurs otherwise MagickTrue.

The format of the ImageToFile method is:

   MagickBooleanType ImageToFile(Image *image,char *filename,
    ExceptionInfo *exception)

A description of each parameter follows:

image

The image.

filename

Write the image to this file.

exception

Return any errors or warnings in this structure.

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

Note, some image formats do not permit multiple images to the same image stream (e.g. JPEG). in this instance, just the first image of the sequence is returned as a blob.

The format of the ImagesToBlob method is:

  unsigned char *ImagesToBlob(const ImageInfo *image_info,Image *images,
    size_t *length,ExceptionInfo *exception)

A description of each parameter follows:

image_info

The image info.

images

The image list.

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.

IsBlobExempt() returns true if the blob is exempt.

The format of the IsBlobExempt method is:

   MagickBooleanType IsBlobExempt(const Image *image)

A description of each parameter follows:

image

The image.

IsBlobSeekable() returns true if the blob is seekable.

The format of the IsBlobSeekable method is:

   MagickBooleanType IsBlobSeekable(const Image *image)

A description of each parameter follows:

image

The image.

IsBlobTemporary() returns true if the blob is temporary.

The format of the IsBlobTemporary method is:

   MagickBooleanType IsBlobTemporary(const Image *image)

A description of each parameter follows:

image

The image.

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.

ReadBlobStream() read data from an image stream. If the stream is memory-mapped, a pointer is returned to the in-memory data otherwise the data is copied to the user supplied buffer and its location is returned.

The format of the ReadBlobStream method is:

  const unsigned char *ReadBlobStream(Image *image,const size_t length,
    unsigned char *data,ssize_t *count)

A description of each parameter follows:

image

The image.

length

The number of bytes to read from the image stream.

data

The user supplied buffer greater or equal to length bytes.

count

Returns the number of bytes read.

SetBlobExempt() sets the blob exempt status.

The format of the SetBlobExempt method is:

  MagickBooleanType SetBlobExempt(const Image *image,
    const MagickBooleanType exempt)

A description of each parameter follows:

image

The image.

exempt

Set to true if this blob is exempt from being closed.