Image

Creates Image from bitmap, sharing or copying bitmap pixels. If the bitmap is marked immutable, and its pixel memory is shareable, it may be shared instead of copied.

Image is returned if bitmap is valid. Valid Bitmap parameters include: dimensions are greater than zero; each dimension fits in 29 bits; ColorType and AlphaType are valid, and ColorType is not kUnknown_ColorType; row bytes are large enough to hold one row of pixels; pixel address is not nil.

Creates Image from ImageInfo, sharing pixels. Image is returned if ImageInfo is valid. Valid ImageInfo parameters include: dimensions are greater than zero; each dimension fits in 29 bits; ColorType and AlphaType are valid, and ColorType is not kUnknown_ColorType; rowBytes are large enough to hold one row of pixels; pixels is not nil, and contains enough data for Image.

Creates Image from pixmap, sharing Pixmap pixels. Pixels must remain valid and unchanged until rasterReleaseProc is called. rasterReleaseProc is passed releaseContext when Image is deleted or no longer refers to pixmap pixels. Pass nil for rasterReleaseProc to share Pixmap without requiring a callback when Image is released. Pass nil for releaseContext if rasterReleaseProc does not require state. Image is returned if pixmap is valid. Valid Pixmap parameters include: dimensions are greater than zero; each dimension fits in 29 bits; ColorType and AlphaType are valid, and ColorType is not kUnknown_ColorType; row bytes are large enough to hold one row of pixels; pixel address is not nil.

Return an image backed by the encoded data, but attempt to defer decoding until the image is actually used/drawn. This deferral allows the system to cache the result, either on the CPU or on the GPU, depending on where the image is drawn. If memory is low, the cache may be purged, causing the next draw of the image to have to re-decode.

The subset parameter specifies a area within the decoded image to create the image from. If subset is null, then the entire image is returned.

This is similar to DecodeTo[Raster,Texture], but this method will attempt to defer the actual decode, while the DecodeTo… method explicitly decode and allocate the backend when the call is made.

If the encoded format is not supported, or subset is outside of the bounds of the decoded image, nil is returned.

Encodes Image pixels, returning result as Data. Returns existing encoded data if present; otherwise, Image is encoded with EncodedImageFormat::kPNG. ia must be built with SK_HAS_PNG_LIBRARY to encode Image. Returns nil if existing encoded data is missing or invalid, and encoding fails.

Encodes Image pixels, returning result as Data. Returns nil if encoding fails, or if encodedImageFormat is not supported.

Image encoding in a format requires both building with one or more of: SK_HAS_JPEG_LIBRARY, SK_HAS_PNG_LIBRARY, SK_HAS_WEBP_LIBRARY; and platform support for the encoded format.

If SK_BUILD_FOR_MAC or SK_BUILD_FOR_IOS is defined, encodedImageFormat can additionally be one of: EncodedImageFormat.ico, EncodedImageFormat.bmp, EncodedImageFormat.gif` quality is a platform and format specific metric trading off size and encoding error. When used, quality equaling 100 encodes with the least error. quality may be ignored by the encoder.

Returns pixel count in each row.

Returns pixel row count.

Returns value unique to image. Image contents cannot change after Image is created. Any operation to create a new Image will receive generate a new unique number.

The AlphaType returned was a parameter to an SkImage constructor, or was parsed from encoded data.

SkColorType if known; otherwise, returns .unknown.

Returns ColorSpace, the range of colors, associated with Image. The reference count of ColorSpace is unchanged. The returned ColorSpace is immutable. ColorSpace returned was passed to an Image constructor, or was parsed from encoded data. ColorSpace returned may be ignored when Image is drawn, depending on the capabilities of the Surface receiving the drawing.

Returns true if Image pixels represent transparency only. If true, each pixel is packed in 8 bits as defined by kAlpha_8_ColorType.

Returns encoded Image pixels as Data, if Image was created from supported encoded stream format. Platform support for formats vary and may require building with one or more of: SK_HAS_JPEG_LIBRARY, SK_HAS_PNG_LIBRARY, SK_HAS_WEBP_LIBRARY. Returns nil if Image contents are not encoded.

Creates Shader from Image. Shader dimensions are taken from Image. Shader uses transforming Image before Canvas matrix is applied.

Creates Shader from Image. Shader dimensions are taken from Image. Shader uses TileMode rules to fill drawn area outside Image. localMatrix permits transforming Image before Canvas matrix is applied.

Copies Image pixel address, row bytes, and ImageInfo to pixmap, if address is available, and returns true. If pixel address is not available, return false and leave pixmap unchanged.

Returns true the contents of Image was created on or uploaded to GPU memory, and is available as a GPU texture.

Returns true if Image is backed by an image-generator or other service that creates and caches its pixels or texture on-demand.

CachingHint selects whether ia may internally cache Bitmap generated by decoding Image, or by copying Image from GPU to CPU. The default behavior allows caching Bitmap.

Choose kDisallow_CachingHint if Image pixels are to be used only once, or if Image pixels reside in a cache outside of ia, or to reduce memory pressure.

Choosing kAllow_CachingHint does not ensure that pixels will be cached. Image pixels may not be cached if memory requirements are too large or pixels are not accessible.

Copies Rect of pixels from Image to dstPixels. Copy starts at offset (srcX, srcY), and does not exceed Image (width(), height()). dstInfo specifies width, height, ColorType, AlphaType, and ColorSpace of destination. dstRowBytes specifies the gap from one destination row to the next. Returns true if pixels are copied. Returns false if:

• dstInfo.addr() equals nil
• dstRowBytes is less than dstInfo.minRowBytes()
• PixelRef is nil Pixels are copied only if pixel conversion is possible. If Image ColorType is .gray8, or .alpha8; dstInfo.colorType() must match. If Image ColorType is .gray8, dstInfo.colorSpace() must match. If Image AlphaType is .opaque, dstInfo.alphaType() must match. If Image ColorSpace is nil, dstInfo.colorSpace must match. Returns false if pixel conversion is not possible. srcX and srcY may be negative to copy only top or left of source. Returns false if width or height is zero or negative. Returns false if abs(srcX) >= Image width(), or if abs(srcY) >= Image height(). If cachingHint is .allow, pixels may be retained locally. If cachingHint is .disallow, pixels are not added to the local cache.

Copies a Rect of pixels from Image to dst. Copy starts at (srcX, srcY), and does not exceed Image (width, height). dst specifies width, height, ColorType, AlphaType, ColorSpace, pixel storage, and row bytes of destination. dst.rowBytes() specifics the gap from one destination row to the next. Returns true if pixels are copied. Returns false if:

• dst pixel storage equals nil
• dst.rowBytes is less than ImageInfo::minRowBytes
• PixelRef is nil Pixels are copied only if pixel conversion is possible. If Image ColorType is .gray8, or .alpha8; dstInfo.colorType() must match. If Image ColorType is .gray8, dstInfo.colorSpace() must match. If Image AlphaType is .opaque, dstInfo.alphaType() must match. If Image ColorSpace is nil, dstInfo.colorSpace must match. Returns false if pixel conversion is not possible. srcX and srcY may be negative to copy only top or left of source. Returns false if width or height is zero or negative. Returns false if abs(srcX) >= Image width(), or if abs(srcY) >= Image height(). If cachingHint is .allow, pixels may be retained locally. If cachingHint is .disallow, pixels are not added to the local cache.

Copies Image to dst, scaling pixels to fit dst.width() and dst.height(), and converting pixels to match dst.colorType() and dst.alphaType(). Returns true if pixels are copied. Returns false if dst.addr() is nil, or dst.rowBytes() is less than dst ImageInfo::minRowBytes. Pixels are copied only if pixel conversion is possible. If Image ColorType is .gray8, or .alpha8; dstInfo.colorType() must match. If Image ColorType is .gray8, dstInfo.colorSpace() must match. If Image AlphaType is .opaque, dstInfo.alphaType() must match. If Image ColorSpace is nil, dstInfo.colorSpace must match. Returns false if pixel conversion is not possible. Scales the image, with quality, to match dst.width() and dst.height(). filterQuality kNone_FilterQuality is fastest, typically implemented with nearest neighbor filter. kLow_FilterQuality is typically implemented with bilerp filter. kMedium_FilterQuality is typically implemented with bilerp filter, and mip-map filter when size is reduced. kHigh_FilterQuality is slowest, typically implemented with bicubic filter. If cachingHint is kAllow_CachingHint, pixels may be retained locally. If cachingHint is kDisallow_CachingHint, pixels are not added to the local cache.

Returns subset of Image. subset must be fully contained by Image dimensions(). The implementation may share pixels, or may copy them. Returns nil if subset is empty, or subset is not contained by bounds, or pixels in Image could not be read or copied.

Returns a raster-based image of the current image.