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kImage Class Reference

Description

Represents a 2D collection of pixels.

The kImage class is similar to the kArray2 class, but has some important differences:

  • By default, image memory is allocated such that rows are aligned to 8-byte boundaries.
  • Pixels are limited to value types.
  • Image indices/dimensions are given in (column, row) rather than (row, column) order.
  • kImage contains additional image-specific attributes (e.g. color filter array type).

In particular, the row-alignment behaviour means that image memory should typically be accessed by getting a pointer to the beginning of a row, and then iterating over pixels. E.g.

kSize height = kImage_Height(image);
kSize width = kImage_Width(image);
kSize i, j;
k32u sum = 0;
for (i = 0; i < height; ++i)
{
k8u* row = kImage_RowAt(image, i);
for (j = 0; j < width; ++j)
{
sum += row[j];
}
}
+ Inheritance diagram for kImage:

Public Member Functions

kStatus kImage_Allocate (kImage image, kType pixelType, kSize width, kSize height)
 Reallocates the internal pixel buffer. More...
 
kSize kImage_Area (kImage image)
 Returns the area of the image, in pixels. More...
 
kStatus kImage_Assign (kImage image, kImage source)
 Copies a given source image into this image. More...
 
void * kImage_At (kImage image, kSize x, kSize y)
 Returns a pointer to the specified pixel in the pixel buffer. More...
 
kStatus kImage_Attach (kImage image, void *pixels, kType pixelType, kSize width, kSize height, kSize stride)
 Attaches the image to an external pixel buffer. More...
 
kCfa kImage_Cfa (kImage image)
 Gets the color filter array type associated with this image. More...
 
kStatus kImage_Construct (kImage *image, kType pixelType, kSize width, kSize height, kAlloc allocator)
 Constructs a kImage object. More...
 
void * kImage_Data (kImage image)
 Returns a pointer to the first row in the pixel buffer. More...
 
kSize kImage_DataSize (kImage image)
 Reports the size, in bytes, of the pixel buffer. More...
 
kStatus kImage_Export (kImage image, const char *fileName)
 Saves an image to file. More...
 
kSize kImage_Height (kImage image)
 Returns the height of the image, in pixels. More...
 
kStatus kImage_Import (kImage *image, const char *fileName, kAlloc allocator)
 Loads an image from file. More...
 
kStatus kImage_Pixel (kImage image, kSize x, kSize y, void *pixel)
 Gets the value of a pixel. More...
 
kPixelFormat kImage_PixelFormat (kImage image)
 Gets the optional pixel format descriptor associated with this image. More...
 
kSize kImage_PixelSize (kImage image)
 Returns the pixel size. More...
 
kType kImage_PixelType (kImage image)
 Returns the pixel type. More...
 
void * kImage_RowAt (kImage image, kSize y)
 Returns a pointer to the specified row in the pixel buffer. More...
 
kStatus kImage_SetCfa (kImage image, kCfa cfa)
 Sets the color filter array type associated with this image. More...
 
kStatus kImage_SetPixel (kImage image, kSize x, kSize y, const void *pixel)
 Sets the value of a pixel. More...
 
kStatus kImage_SetPixelFormat (kImage image, kPixelFormat format)
 Sets the optional pixel format descriptor associated with this image. More...
 
kSize kImage_Stride (kImage image)
 Returns the size of an image row, including alignment padding bytes, in bytes. More...
 
kSize kImage_Width (kImage image)
 Returns the width of the image, in pixels. More...
 
kStatus kImage_Zero (kImage image)
 Sets all pixel bits to zero. More...
 
kAlloc kObject_Alloc (kObject object)
 Gets the memory allocator associated with this object. More...
 
kStatus kObject_Clone (kObject *object, kObject source, kAlloc allocator)
 Constructs a new object by copying an existing object, including any aggregated child elements. More...
 
kStatus kObject_Destroy (kObject object)
 Destroys the object. More...
 
kStatus kObject_Dispose (kObject object)
 Destroys the object and any aggregated child elements. More...
 
kBool kObject_Equals (kObject object, kObject other)
 Determines whether the object is equal to another object. More...
 
kSize kObject_HashCode (kObject object)
 Gets a hash code representing the state of this object. More...
 
kBool kObject_Is (kObject object, kType type)
 Determines whether this object is an instance of the specified type. More...
 
kBool kObject_IsShared (kObject object)
 Reports whether the object is currently shared (reference count greater than one). More...
 
kStatus kObject_SetPool (kObject object, kObjectPool pool)
 Sets the object pool associated with this object. More...
 
kStatus kObject_Share (kObject object)
 Increments the reference count associated with this object. More...
 
kSize kObject_Size (kObject object)
 Estimates the memory consumed by this object, including any aggregated child elements. More...
 
kType kObject_Type (kObject object)
 Returns the type of the object. More...
 

Member Function Documentation

kStatus kImage_Allocate ( kImage  image,
kType  pixelType,
kSize  width,
kSize  height 
)

Reallocates the internal pixel buffer.

Parameters
imageImage object.
pixelTypeType of pixel (values types only).
widthImage width, in pixels.
heightImage height, in pixels.
Returns
Operation status.
kSize kImage_Area ( kImage  image)

Returns the area of the image, in pixels.

Image area is the product of image width and image height.

Parameters
imageImage object.
Returns
Image area (pixels).
kStatus kImage_Assign ( kImage  image,
kImage  source 
)

Copies a given source image into this image.

Parameters
imageImage object.
sourceSource image to be copied.
Returns
Operation status.
void * kImage_At ( kImage  image,
kSize  x,
kSize  y 
)

Returns a pointer to the specified pixel in the pixel buffer.

Parameters
imageImage object.
xColumn index.
yRow index.
Returns
Pointer to pixel.
kStatus kImage_Attach ( kImage  image,
void *  pixels,
kType  pixelType,
kSize  width,
kSize  height,
kSize  stride 
)

Attaches the image to an external pixel buffer.

Attached pixel buffers are not freed when the image is destroyed.

Parameters
imageImage object.
pixelsPointer to external pixel buffer.
pixelTypeType of pixel (values types only).
widthImage width, in pixels.
heightImage height, in pixels.
strideImage stride (row size), in bytes.
Returns
Operation status.
kCfa kImage_Cfa ( kImage  image)

Gets the color filter array type associated with this image.

Parameters
imageImage object.
Returns
Color filter array type.
kStatus kImage_Construct ( kImage image,
kType  pixelType,
kSize  width,
kSize  height,
kAlloc  allocator 
)

Constructs a kImage object.

Parameters
imageReceives the constructed image object.
pixelTypePixel type (must be a value type).
widthImage width.
heightImage height.
allocatorMemory allocator.
Returns
Operation status.
void * kImage_Data ( kImage  image)

Returns a pointer to the first row in the pixel buffer.

Parameters
imageImage object.
Returns
Pointer to pixel buffer.
kSize kImage_DataSize ( kImage  image)

Reports the size, in bytes, of the pixel buffer.

Parameters
imageImage object.
Returns
Size of pixel buffer (bytes).
kStatus kImage_Export ( kImage  image,
const char *  fileName 
)

Saves an image to file.

The file extension is used to determine to image format. Currently, only the BMP (.bmp) format is supported.

Parameters
imageImage object.
fileNameFile path.
Returns
Operation status.
kSize kImage_Height ( kImage  image)

Returns the height of the image, in pixels.

Parameters
imageImage object.
Returns
Image height (pixels).
kStatus kImage_Import ( kImage image,
const char *  fileName,
kAlloc  allocator 
)

Loads an image from file.

The file extension is used to determine to image format. Currently, only the BMP (.bmp) format is supported.

Parameters
imageReceives the constructed image object.
fileNameFile path.
allocatorMemory allocator (or kNULL for default).
Returns
Operation status.
kStatus kImage_Pixel ( kImage  image,
kSize  x,
kSize  y,
void *  pixel 
)

Gets the value of a pixel.

This method is convenient in some contexts, but is not an efficient method to access many pixels. In performance-critical code, use kImage_RowAt to directly access the pixel buffer.

Parameters
imageImage object.
xColumn index.
yRow index.
pixelDestination for pixel copied from the image.
Returns
Operation status.
kPixelFormat kImage_PixelFormat ( kImage  image)

Gets the optional pixel format descriptor associated with this image.

Parameters
imageImage object.
Returns
Pixel format.
kSize kImage_PixelSize ( kImage  image)

Returns the pixel size.

Parameters
imageImage object.
Returns
Pixel size, in bytes.
kType kImage_PixelType ( kImage  image)

Returns the pixel type.

Parameters
imageImage object.
Returns
Pixel type.
void * kImage_RowAt ( kImage  image,
kSize  y 
)

Returns a pointer to the specified row in the pixel buffer.

Parameters
imageImage object.
yRow index.
Returns
Pointer to first pixel in row.
kStatus kImage_SetCfa ( kImage  image,
kCfa  cfa 
)

Sets the color filter array type associated with this image.

Parameters
imageImage object.
cfaColor filter array type.
Returns
Operation status.
kStatus kImage_SetPixel ( kImage  image,
kSize  x,
kSize  y,
const void *  pixel 
)

Sets the value of a pixel.

This method is convenient in some contexts, but is not an efficient method to manipulate many pixels. In performance-critical code, use kImage_RowAt to directly access the pixel buffer.

Parameters
imageImage object.
xColumn index.
yRow index.
pixelPointer to pixel value that will be copied into the image.
Returns
Operation status.
kStatus kImage_SetPixelFormat ( kImage  image,
kPixelFormat  format 
)

Sets the optional pixel format descriptor associated with this image.

Parameters
imageImage object.
formatPixel format.
Returns
Operation status.
kSize kImage_Stride ( kImage  image)

Returns the size of an image row, including alignment padding bytes, in bytes.

Parameters
imageImage object.
Returns
Image stride (bytes).
kSize kImage_Width ( kImage  image)

Returns the width of the image, in pixels.

Parameters
imageImage object.
Returns
Image width (pixels).
kStatus kImage_Zero ( kImage  image)

Sets all pixel bits to zero.

Parameters
imageImage object.
Returns
Operation status.
kAlloc kObject_Alloc ( kObject  object)
inherited

Gets the memory allocator associated with this object.

Most objects are constructed with an allocator, which is used to allocate the memory required by the object. Objects retain a reference to this allocator to enable further allocations and to free memory when the object is destroyed.

Parameters
objectObject.
Returns
Memory allocator.
See also
kAlloc, kObject_Alloc_
kStatus kObject_Clone ( kObject object,
kObject  source,
kAlloc  allocator 
)
inherited

Constructs a new object by copying an existing object, including any aggregated child elements.

If the source object is an object collection (e.g. kArrayList<kString>), any aggregated child objects are also cloned. In this case, the kObject_Dispose method can be used to free the cloned collection and its associated elements.

This method will fail if the source object (or an aggregated child element) does not support cloning.

Parameters
objectReceives the constructed object.
sourceSource object.
allocatorMemory allocator (or kNULL for default).
Returns
Operation status.
See also
kObject_Dispose
kStatus kObject_Destroy ( kObject  object)
inherited

Destroys the object.

The kObject_Destroy method destroys the object itself and any resources that are owned by the object. See Object Destruction for more information.

When an object is destroyed (or disposed), its reference count is decremented. The object is only truly destroyed when the reference count reaches zero. See Reference Counting for more information.

Parameters
objectObject (or kNULL).
Returns
Operation status.
See also
Object Destruction, Reference Counting
kStatus kObject_Dispose ( kObject  object)
inherited

Destroys the object and any aggregated child elements.

The kObject_Dispose method destroys the object itself, any resources that are owned by the object, and if the object represents a collection of objects, any child objects in the collection. See Object Destruction for more information.

When an object is destroyed (or disposed), its reference count is decremented. The object is only truly destroyed when the reference count reaches zero. See Reference Counting for more information.

Parameters
objectObject (or kNULL).
Returns
Operation status.
See also
Object Destruction, Reference Counting
kBool kObject_Equals ( kObject  object,
kObject  other 
)
inherited

Determines whether the object is equal to another object.

By default, objects are compared by reference; objects are considered equal if the given handles refer to the same object instance. However, some classes override the Equals method to provide a more meaningful comparison (e.g. kString).

Parameters
objectObject.
otherObject for comparison.
Returns
kTRUE if the objects are equal.
kSize kObject_HashCode ( kObject  object)
inherited

Gets a hash code representing the state of this object.

By default, objects return a hash code based on the object handle value. However, some classes override the HashCode method to provide a more useful hash (e.g. kString).

Parameters
objectObject.
Returns
Hash code.
kBool kObject_Is ( kObject  object,
kType  type 
)
inherited

Determines whether this object is an instance of the specified type.

This function compares the type of this object with the given type. An object is considered to be an instance of a given type if a) the type represents a class and this object inherits from (or instantiates) that class, or b) the type represents an interface and this object implements the interface.

Parameters
objectObject.
typeType.
Returns
kTRUE if the object is of the specified type; otherwise kFALSE.
See also
kObject_Is_, kType_Is
kBool kObject_IsShared ( kObject  object)
inherited

Reports whether the object is currently shared (reference count greater than one).

Objects are initialized with a reference count of one. The kObject_Share method can be used to increment the reference count. The kObject_Destroy and kObject_Dispose methods decrease the reference count, and when the reference count reaches zero, the object is actually destroyed/disposed.

This method can be used to determine if the reference count of an object is currently greater than one.

This method is thread-safe.

Parameters
objectObject.
Returns
kTRUE if the object is shared; kFALSE otherwise.
See also
Reference Counting, kObject_Share
kStatus kObject_SetPool ( kObject  object,
kObjectPool  pool 
)
inherited

Sets the object pool associated with this object.

Object pools can be used to implement custom lifecycle management. If an object has an assigned pool, then the kObjectPool_Reclaim method will be called just prior to destruction, to provide an opportunity for the object to be reclaimed.

Parameters
objectObject.
poolPool object (or kNULL to clear the pool assignment).
Returns
Operation status.
kStatus kObject_Share ( kObject  object)
inherited

Increments the reference count associated with this object.

This method is thread-safe.

Parameters
objectObject.
Returns
Operation status.
See also
reference-counting
kSize kObject_Size ( kObject  object)
inherited

Estimates the memory consumed by this object, including any aggregated child elements.

This method can be optionally overridden by kObject-derived classes to report the amount of memory consumed by an object. The default implementation reports only the size of the class instance (additional allocations performed by the class are excluded).

Parameters
objectObject.
Returns
Object size, in bytes.
kType kObject_Type ( kObject  object)
inherited

Returns the type of the object.

Each object is an instance of a specific class type. The type handle returned by this function can be used to learn about the class.

Parameters
objectObject.
Returns
Type.
See also
kType, kObject_Type_

The documentation for this class was generated from the following file: