Method: Magick::ImageList#to_blob

Defined in:
ext/RMagick/rmilist.c

#to_blob ⇒ Object

Return the imagelist as a blob (a String).

Ruby usage:

- @verbatim ImageList#to_blob @endverbatim

Notes:

- Runs an info parm block if present - the user can specify the image
  format and depth

Parameters:

  • self —

    this object

Returns:

  • the blob



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# File 'ext/RMagick/rmilist.c', line 1164

VALUE
ImageList_to_blob(VALUE self)
{
    Image *images, *image;
    Info *info;
    VALUE info_obj;
    VALUE blob_str;
    void *blob = NULL;
    size_t length = 0;
    ExceptionInfo *exception;

    info_obj = rm_info_new();
    Data_Get_Struct(info_obj, Info, info);

    // Convert the images array to an images sequence.
    images = images_from_imagelist(self);

    exception = AcquireExceptionInfo();
    (void) SetImageInfo(info, MagickTrue, exception);
    rm_check_exception(exception, images, RetainOnError);

    if (*info->magick != '\0')
    {
        Image *img;
        for (img = images; img; img = GetNextImageInList(img))
        {
            strncpy(img->magick, info->magick, sizeof(info->magick)-1);
        }
    }

    for (image = images; image; image = GetNextImageInList(image))
    {
        rm_sync_image_options(image, info);
    }

    // Unconditionally request multi-images support. The worst that
    // can happen is that there's only one image or the format
    // doesn't support multi-image files.
    info->adjoin = MagickTrue;
    blob = ImagesToBlob(info, images, &length, exception);
    if (blob && exception->severity >= ErrorException)
    {
        magick_free((void*)blob);
        blob = NULL;
        length = 0;
    }
    rm_split(images);
    CHECK_EXCEPTION()
    (void) DestroyExceptionInfo(exception);


    if (length == 0 || !blob)
    {
        return Qnil;
    }

    blob_str = rb_str_new(blob, (long)length);
    magick_free((void*)blob);

    RB_GC_GUARD(info_obj);
    RB_GC_GUARD(blob_str);

    return blob_str;
}