arsd.jpeg

Loads a JPEG image from a memory buffer or a file.

req_comps can be 1 (grayscale), 3 (RGB), or 4 (RGBA). On return, width/height will be set to the image's dimensions, and actual_comps will be set to the either 1 (grayscale) or 3 (RGB). Requesting a 8 or 32bpp image is currently a little faster than 24bpp because the jpeg_decoder class itself currently always unpacks to either 8 or 32bpp.

Members

Aliases

JpegStreamReadFunc alias JpegStreamReadFunc = int delegate(void* pBuf, int max_bytes_to_read, bool* pEOF_flag): Input stream interface. This delegate is called when the internal input buffer is empty.

Enums

JpegSubsampling enum JpegSubsampling: Writes a JPEG image to a file or stream. num_channels must be 1 (Y), 3 (RGB), 4 (RGBA), image pitch must be width*num_channels. note that alpha will not be stored in jpeg file.

Functions

compress_image_to_jpeg_file bool compress_image_to_jpeg_file(const(char)[] fname, int width, int height, int num_channels, const(ubyte)[] pImage_data): Writes JPEG image to file. num_channels must be 1 (Y), 3 (RGB), 4 (RGBA), image pitch must be width*num_channels. note that alpha will not be stored in jpeg file.
compress_image_to_jpeg_file bool compress_image_to_jpeg_file(const(char)[] fname, int width, int height, int num_channels, const(ubyte)[] pImage_data, JpegParams comp_params): Writes JPEG image to file. num_channels must be 1 (Y), 3 (RGB), 4 (RGBA), image pitch must be width*num_channels. note that alpha will not be stored in jpeg file.
compress_image_to_jpeg_stream bool compress_image_to_jpeg_stream(jpeg_encoder.WriteFunc wfn, int width, int height, int num_channels, const(ubyte)[] pImage_data): Writes JPEG image to file. num_channels must be 1 (Y), 3 (RGB), 4 (RGBA), image pitch must be width*num_channels. note that alpha will not be stored in jpeg file.
compress_image_to_jpeg_stream bool compress_image_to_jpeg_stream(jpeg_encoder.WriteFunc wfn, int width, int height, int num_channels, const(ubyte)[] pImage_data, JpegParams comp_params): Writes JPEG image to file. num_channels must be 1 (Y), 3 (RGB), 4 (RGBA), image pitch must be width*num_channels. note that alpha will not be stored in jpeg file.
decompress_jpeg_image_from_file ubyte[] decompress_jpeg_image_from_file(const(char)[] filename, int width, int height, int actual_comps, int req_comps): decompress JPEG image from disk file. you can specify required color components in req_comps (3 for RGB or 4 for RGBA), or leave it as is to use image value.
decompress_jpeg_image_from_file ubyte[] decompress_jpeg_image_from_file(VFile fl, int width, int height, int actual_comps, int req_comps): decompress JPEG image from disk file. you can specify required color components in req_comps (3 for RGB or 4 for RGBA), or leave it as is to use image value.
decompress_jpeg_image_from_memory ubyte[] decompress_jpeg_image_from_memory(const(void)[] buf, int width, int height, int actual_comps, int req_comps): decompress JPEG image from memory buffer. you can specify required color components in req_comps (3 for RGB or 4 for RGBA), or leave it as is to use image value.
decompress_jpeg_image_from_stream ubyte[] decompress_jpeg_image_from_stream(JpegStreamReadFunc rfn, int width, int height, int actual_comps, int req_comps): decompress JPEG image, what else? you can specify required color components in req_comps (3 for RGB or 4 for RGBA), or leave it as is to use image value.
detect_jpeg_image_from_file bool detect_jpeg_image_from_file(const(char)[] filename, int width, int height, int actual_comps): read JPEG image header, determine dimensions and number of components. return false if image is not JPEG (i hope).
detect_jpeg_image_from_memory bool detect_jpeg_image_from_memory(const(void)[] buf, int width, int height, int actual_comps): read JPEG image header, determine dimensions and number of components. return false if image is not JPEG (i hope).
detect_jpeg_image_from_stream bool detect_jpeg_image_from_stream(JpegStreamReadFunc rfn, int width, int height, int actual_comps): read JPEG image header, determine dimensions and number of components. return false if image is not JPEG (i hope).
encodeJpeg ubyte[] encodeJpeg(TrueColorImage img, JpegParams params)
void encodeJpeg(bool delegate(const scope ubyte[]) dg, TrueColorImage img, JpegParams params): Encodes an image as jpeg in memory.
readJpeg MemoryImage readJpeg(const(char)[] filename): decompress JPEG image from disk file. Returns null if loading failed for any reason.
readJpegFromMemory MemoryImage readJpegFromMemory(const(void)[] buf): decompress JPEG image from memory buffer.
readJpegFromStream MemoryImage readJpegFromStream(JpegStreamReadFunc rfn): decompress JPEG image, what else?
writeJpeg void writeJpeg(const(char)[] filename, TrueColorImage img, JpegParams params)

Structs

JpegParams struct JpegParams: JPEG compression parameters structure.