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/* Copyright (c) the JPEG XL Project Authors. All rights reserved.
*
* Use of this source code is governed by a BSD-style
* license that can be found in the LICENSE file.
*/
/** @addtogroup libjxl_common
* @{
* @file types.h
* @brief Data types for the JPEG XL API, for both encoding and decoding.
*/
#ifndef JXL_TYPES_H_
#define JXL_TYPES_H_
#include <stddef.h>
#include <stdint.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* A portable @c bool replacement.
*
* ::JXL_BOOL is a "documentation" type: actually it is @c int, but in API it
* denotes a type, whose only values are ::JXL_TRUE and ::JXL_FALSE.
*/
#define JXL_BOOL int
/** Portable @c true replacement. */
#define JXL_TRUE 1
/** Portable @c false replacement. */
#define JXL_FALSE 0
/** Converts of bool-like value to either ::JXL_TRUE or ::JXL_FALSE. */
#define TO_JXL_BOOL(C) (!!(C) ? JXL_TRUE : JXL_FALSE)
/** Converts JXL_BOOL to C++ bool. */
#define FROM_JXL_BOOL(C) (static_cast<bool>(C))
/** Data type for the sample values per channel per pixel.
*/
typedef enum {
/** Use 32-bit single-precision floating point values, with range 0.0-1.0
* (within gamut, may go outside this range for wide color gamut). Floating
* point output, either ::JXL_TYPE_FLOAT or ::JXL_TYPE_FLOAT16, is recommended
* for HDR and wide gamut images when color profile conversion is required. */
JXL_TYPE_FLOAT = 0,
/** Use type uint8_t. May clip wide color gamut data.
*/
JXL_TYPE_UINT8 = 2,
/** Use type uint16_t. May clip wide color gamut data.
*/
JXL_TYPE_UINT16 = 3,
/** Use 16-bit IEEE 754 half-precision floating point values */
JXL_TYPE_FLOAT16 = 5,
} JxlDataType;
/** Ordering of multi-byte data.
*/
typedef enum {
/** Use the endianness of the system, either little endian or big endian,
* without forcing either specific endianness. Do not use if pixel data
* should be exported to a well defined format.
*/
JXL_NATIVE_ENDIAN = 0,
/** Force little endian */
JXL_LITTLE_ENDIAN = 1,
/** Force big endian */
JXL_BIG_ENDIAN = 2,
} JxlEndianness;
/** Data type for the sample values per channel per pixel for the output buffer
* for pixels. This is not necessarily the same as the data type encoded in the
* codestream. The channels are interleaved per pixel. The pixels are
* organized row by row, left to right, top to bottom.
* TODO(lode): support different channel orders if needed (RGB, BGR, ...)
*/
typedef struct {
/** Amount of channels available in a pixel buffer.
* 1: single-channel data, e.g. grayscale or a single extra channel
* 2: single-channel + alpha
* 3: trichromatic, e.g. RGB
* 4: trichromatic + alpha
* TODO(lode): this needs finetuning. It is not yet defined how the user
* chooses output color space. CMYK+alpha needs 5 channels.
*/
uint32_t num_channels;
/** Data type of each channel.
*/
JxlDataType data_type;
/** Whether multi-byte data types are represented in big endian or little
* endian format. This applies to ::JXL_TYPE_UINT16 and ::JXL_TYPE_FLOAT.
*/
JxlEndianness endianness;
/** Align scanlines to a multiple of align bytes, or 0 to require no
* alignment at all (which has the same effect as value 1)
*/
size_t align;
} JxlPixelFormat;
/** Settings for the interpretation of UINT input and output buffers.
* (buffers using a FLOAT data type are not affected by this)
*/
typedef enum {
/** This is the default setting, where the encoder expects the input pixels
* to use the full range of the pixel format data type (e.g. for UINT16, the
* input range is 0 .. 65535 and the value 65535 is mapped to 1.0 when
* converting to float), and the decoder uses the full range to output
* pixels. If the bit depth in the basic info is different from this, the
* encoder expects the values to be rescaled accordingly (e.g. multiplied by
* 65535/4095 for a 12-bit image using UINT16 input data type). */
JXL_BIT_DEPTH_FROM_PIXEL_FORMAT = 0,
/** If this setting is selected, the encoder expects the input pixels to be
* in the range defined by the bits_per_sample value of the basic info (e.g.
* for 12-bit images using UINT16 input data types, the allowed range is
* 0 .. 4095 and the value 4095 is mapped to 1.0 when converting to float),
* and the decoder outputs pixels in this range. */
JXL_BIT_DEPTH_FROM_CODESTREAM = 1,
/** This setting can only be used in the decoder to select a custom range for
* pixel output */
JXL_BIT_DEPTH_CUSTOM = 2,
} JxlBitDepthType;
/** Data type for describing the interpretation of the input and output buffers
* in terms of the range of allowed input and output pixel values. */
typedef struct {
/** Bit depth setting, see comment on @ref JxlBitDepthType */
JxlBitDepthType type;
/** Custom bits per sample */
uint32_t bits_per_sample;
/** Custom exponent bits per sample */
uint32_t exponent_bits_per_sample;
} JxlBitDepth;
/** Data type holding the 4-character type name of an ISOBMFF box.
*/
typedef char JxlBoxType[4];
#ifdef __cplusplus
}
#endif
#endif /* JXL_TYPES_H_ */
/** @}*/