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/*
* Copyright 2024 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/** \file ultrahdr_api.h
*
* \brief
* Describes the encoder or decoder algorithm interface to applications.
*/
#ifndef ULTRAHDR_API_H
#define ULTRAHDR_API_H
#ifdef __cplusplus
#define UHDR_EXTERN extern "C"
#else
#define UHDR_EXTERN extern
#endif
// ===============================================================================================
// Enum Definitions
// ===============================================================================================
/*!\brief List of supported image formats */
typedef enum uhdr_img_fmt {
UHDR_IMG_FMT_UNSPECIFIED = -1, /**< Unspecified */
UHDR_IMG_FMT_24bppYCbCrP010, /**< 10-bit-per component 4:2:0 YCbCr semiplanar format.
Each chroma and luma component has 16 allocated bits in
little-endian configuration with 10 MSB of actual data.*/
UHDR_IMG_FMT_12bppYCbCr420, /**< 8-bit-per component 4:2:0 YCbCr planar format */
UHDR_IMG_FMT_8bppYCbCr400, /**< 8-bit-per component Monochrome format */
UHDR_IMG_FMT_32bppRGBA8888, /**< 32 bits per pixel RGBA color format, with 8-bit red, green, blue
and alpha components. Using 32-bit little-endian representation,
colors stored as Red 7:0, Green 15:8, Blue 23:16, Alpha 31:24. */
UHDR_IMG_FMT_64bppRGBAHalfFloat, /**< 64 bits per pixel RGBA color format, with 16-bit signed
floating point red, green, blue, and alpha components */
UHDR_IMG_FMT_32bppRGBA1010102, /**< 32 bits per pixel RGBA color format, with 10-bit red, green,
blue, and 2-bit alpha components. Using 32-bit little-endian
representation, colors stored as Red 9:0, Green 19:10, Blue
29:20, and Alpha 31:30. */
} uhdr_img_fmt_t; /**< alias for enum uhdr_img_fmt */
/*!\brief List of supported color gamuts */
typedef enum uhdr_color_gamut {
UHDR_CG_UNSPECIFIED = -1, /**< Unspecified */
UHDR_CG_BT_709, /**< BT.709 */
UHDR_CG_DISPLAY_P3, /**< Display P3 */
UHDR_CG_BT_2100, /**< BT.2100 */
} uhdr_color_gamut_t; /**< alias for enum uhdr_color_gamut */
/*!\brief List of supported color transfers */
typedef enum uhdr_color_transfer {
UHDR_CT_UNSPECIFIED = -1, /**< Unspecified */
UHDR_CT_LINEAR, /**< Linear */
UHDR_CT_HLG, /**< Hybrid log gamma */
UHDR_CT_PQ, /**< Perceptual Quantizer */
UHDR_CT_SRGB, /**< Gamma */
} uhdr_color_transfer_t; /**< alias for enum uhdr_color_transfer */
/*!\brief List of supported color ranges */
typedef enum uhdr_color_range {
UHDR_CR_UNSPECIFIED = -1, /**< Unspecified */
UHDR_CR_LIMITED_RANGE, /**< Y {[16..235], UV [16..240]} * pow(2, (bpc - 8)) */
UHDR_CR_FULL_RANGE, /**< YUV/RGB {[0..255]} * pow(2, (bpc - 8)) */
} uhdr_color_range_t; /**< alias for enum uhdr_color_range */
/*!\brief List of supported codecs */
typedef enum uhdr_codec {
UHDR_CODEC_JPG, /**< Compress {Hdr, Sdr rendition} to an {Sdr rendition + Gain Map} using
jpeg */
} uhdr_codec_t; /**< alias for enum uhdr_codec */
/*!\brief Image identifiers in gain map technology */
typedef enum uhdr_img_label {
UHDR_HDR_IMG, /**< Hdr rendition image */
UHDR_SDR_IMG, /**< Sdr rendition image */
UHDR_BASE_IMG, /**< Base rendition image */
UHDR_GAIN_MAP_IMG, /**< Gain map image */
} uhdr_img_label_t; /**< alias for enum uhdr_img_label */
/*!\brief Algorithm return codes */
typedef enum uhdr_codec_err {
/*!\brief Operation completed without error */
UHDR_CODEC_OK,
/*!\brief Unspecified error */
UHDR_CODEC_UNKNOWN_ERROR,
/*!\brief An application-supplied parameter is not valid. */
UHDR_CODEC_INVALID_PARAM,
/*!\brief Memory operation failed */
UHDR_CODEC_MEM_ERROR,
/*!\brief An application-invoked operation is not valid. */
UHDR_CODEC_INVALID_OPERATION,
/*!\brief The library does not implement a feature required for the operation */
UHDR_CODEC_UNSUPPORTED_FEATURE,
/*!\brief An iterator reached the end of list. */
UHDR_CODEC_LIST_END,
} uhdr_codec_err_t; /**< alias for enum uhdr_codec_err */
// ===============================================================================================
// Structure Definitions
// ===============================================================================================
/*!\brief Detailed return status */
typedef struct uhdr_error_info {
uhdr_codec_err_t error_code;
int has_detail;
char detail[256];
} uhdr_error_info_t; /**< alias for struct uhdr_error_info */
/**\brief Raw Image Descriptor */
typedef struct uhdr_raw_image {
/* Color model, primaries, transfer, range */
uhdr_img_fmt_t fmt; /**< Image Format */
uhdr_color_gamut_t cg; /**< Color Gamut */
uhdr_color_transfer_t ct; /**< Color Transfer */
uhdr_color_range_t range; /**< Color Range */
/* Image storage dimensions */
unsigned int w; /**< Stored image width */
unsigned int h; /**< Stored image height */
/* Image data pointers. */
#define UHDR_PLANE_PACKED 0 /**< To be used for all packed formats */
#define UHDR_PLANE_Y 0 /**< Y (Luminance) plane */
#define UHDR_PLANE_U 1 /**< U (Chroma) plane */
#define UHDR_PLANE_UV 1 /**< UV (Chroma plane interleaved) To be used for semi planar format */
#define UHDR_PLANE_V 2 /**< V (Chroma) plane */
void* planes[3]; /**< pointer to the top left pixel for each plane */
unsigned int stride[3]; /**< stride in pixels between rows for each plane */
} uhdr_raw_image_t; /**< alias for struct uhdr_raw_image */
/**\brief Compressed Image Descriptor */
typedef struct uhdr_compressed_image {
void* data; /**< Pointer to a block of data to decode */
unsigned int data_sz; /**< size of the data buffer */
unsigned int capacity; /**< maximum size of the data buffer */
uhdr_color_gamut_t cg; /**< Color Gamut */
uhdr_color_transfer_t ct; /**< Color Transfer */
uhdr_color_range_t range; /**< Color Range */
} uhdr_compressed_image_t; /**< alias for struct uhdr_compressed_image */
/**\brief Buffer Descriptor */
typedef struct uhdr_mem_block {
void* data; /**< Pointer to a block of data to decode */
unsigned int data_sz; /**< size of the data buffer */
unsigned int capacity; /**< maximum size of the data buffer */
} uhdr_mem_block_t; /**< alias for struct uhdr_mem_block */
/**\brief Gain map metadata.
* Note: all values stored in linear space. This differs from the metadata encoded in XMP, where
* max_content_boost (aka gainMapMax), min_content_boost (aka gainMapMin), hdr_capacity_min, and
* hdr_capacity_max are stored in log2 space.
*/
typedef struct uhdr_gainmap_metadata {
float max_content_boost; /**< Max Content Boost for the map */
float min_content_boost; /**< Min Content Boost for the map */
float gamma; /**< Gamma of the map data */
float offset_sdr; /**< Offset for SDR data in map calculations */
float offset_hdr; /**< Offset for HDR data in map calculations */
float hdr_capacity_min; /**< Min HDR capacity values for interpolating the Gain Map */
float hdr_capacity_max; /**< Max HDR capacity value for interpolating the Gain Map */
} uhdr_gainmap_metadata_t; /**< alias for struct uhdr_gainmap_metadata */
/**\brief ultrahdr codec context opaque descriptor */
typedef struct uhdr_codec_private uhdr_codec_private_t;
// ===============================================================================================
// Function Declarations
// ===============================================================================================
// ===============================================================================================
// Encoder APIs
// ===============================================================================================
/*!\brief Create a new encoder instance. The instance is initialized with default settings.
* To override the settings use uhdr_enc_set_*()
*
* \return nullptr if there was an error allocating memory else a fresh opaque encoder handle
*/
UHDR_EXTERN uhdr_codec_private_t* uhdr_create_encoder(void);
/*!\brief Release encoder instance.
* Frees all allocated storage associated with encoder instance.
*
* \param[in] enc encoder instance.
*
* \return none
*/
UHDR_EXTERN void uhdr_release_encoder(uhdr_codec_private_t* enc);
/*!\brief Add raw image descriptor to encoder context. The function goes through all the fields of
* the image descriptor and checks for their sanity. If no anomalies are seen then the image is
* added to internal list. Repeated calls to this function will replace the old entry with the
* current.
*
* \param[in] enc encoder instance.
* \param[in] img image descriptor.
* \param[in] intent UHDR_HDR_IMG for hdr intent and UHDR_SDR_IMG for sdr intent.
*
* \return uhdr_error_info_t #UHDR_CODEC_OK if operation succeeds,
* #UHDR_CODEC_INVALID_PARAM otherwise.
*/
UHDR_EXTERN uhdr_error_info_t uhdr_enc_set_raw_image(uhdr_codec_private_t* enc,
uhdr_raw_image_t* img,
uhdr_img_label_t intent);
/*!\brief Add compressed image descriptor to encoder context. The function goes through all the
* fields of the image descriptor and checks for their sanity. If no anomalies are seen then the
* image is added to internal list. Repeated calls to this function will replace the old entry with
* the current.
*
* If both uhdr_enc_add_raw_image() and uhdr_enc_add_compressed_image() are called during a session
* for the same intent, it is assumed that raw image descriptor and compressed image descriptor are
* relatable via compress <-> decompress process.
*
* \param[in] enc encoder instance.
* \param[in] img image descriptor.
* \param[in] intent UHDR_HDR_IMG for hdr intent,
* UHDR_SDR_IMG for sdr intent,
* UHDR_BASE_IMG for base image intent
*
* \return uhdr_error_info_t #UHDR_CODEC_OK if operation succeeds,
* #UHDR_CODEC_INVALID_PARAM otherwise.
*/
UHDR_EXTERN uhdr_error_info_t uhdr_enc_set_compressed_image(uhdr_codec_private_t* enc,
uhdr_compressed_image_t* img,
uhdr_img_label_t intent);
/*!\brief Add gain map image descriptor and gainmap metadata info to encoder context. The function
* internally goes through all the fields of the image descriptor and checks for their sanity. If no
* anomalies are seen then the image is added to internal list. Repeated calls to this function will
* replace the old entry with the current.
*
* \param[in] enc encoder instance.
* \param[in] img gain map image desciptor.
* \param[in] metadata gainmap metadata descriptor
*
* \return uhdr_error_info_t #UHDR_CODEC_OK if operation succeeds,
* #UHDR_CODEC_INVALID_PARAM otherwise.
*/
uhdr_error_info_t uhdr_enc_set_gainmap_image(uhdr_codec_private_t* enc,
uhdr_compressed_image_t* img,
uhdr_gainmap_metadata_t* metadata);
/*!\brief Set quality for compression
*
* \param[in] enc encoder instance.
* \param[in] quality quality factor.
* \param[in] intent UHDR_BASE_IMG for base image and UHDR_GAIN_MAP_IMG for gain map image.
*
* \return uhdr_error_info_t #UHDR_CODEC_OK if operation succeeds,
* #UHDR_CODEC_INVALID_PARAM otherwise.
*/
UHDR_EXTERN uhdr_error_info_t uhdr_enc_set_quality(uhdr_codec_private_t* enc, int quality,
uhdr_img_label_t intent);
/*!\brief Set Exif data that needs to be inserted in the output compressed stream
*
* \param[in] enc encoder instance.
* \param[in] img exif data descriptor.
*
* \return uhdr_error_info_t #UHDR_CODEC_OK if operation succeeds,
* #UHDR_CODEC_INVALID_PARAM otherwise.
*/
UHDR_EXTERN uhdr_error_info_t uhdr_enc_set_exif_data(uhdr_codec_private_t* enc,
uhdr_mem_block_t* exif);
/*!\brief Set output image compression format.
*
* \param[in] enc encoder instance.
* \param[in] media_type output image compression format.
*
* \return uhdr_error_info_t #UHDR_CODEC_OK if operation succeeds,
* #UHDR_CODEC_INVALID_PARAM otherwise.
*/
UHDR_EXTERN uhdr_error_info_t uhdr_enc_set_output_format(uhdr_codec_private_t* enc,
uhdr_codec_t media_type);
/*!\brief Encode process call
* After initializing the encoder context, call to this function will submit data for encoding. If
* the call is successful, the encoded output is stored internally and is accessible via
* uhdr_get_encoded_stream().
*
* The basic usage of uhdr encoder is as follows:
* - The program creates an instance of an encoder using,
* - uhdr_create_encoder().
* - The program registers input images to the encoder using,
* - uhdr_enc_set_raw_image(ctxt, img, UHDR_HDR_IMG)
* - uhdr_enc_set_raw_image(ctxt, img, UHDR_SDR_IMG)
* - The program overrides the default settings using uhdr_enc_set_*() functions
* - If the application wants to control the compression level
* - uhdr_enc_set_quality()
* - If the application wants to insert exif data
* - uhdr_enc_set_exif_data()
* - If the application wants to control target compression format
* - uhdr_enc_set_output_format()
* - The program calls uhdr_encode() to encode data. This call would initiate the process of
* computing gain map from hdr intent and sdr intent. The sdr intent and gain map image are
* compressed at the set quality using the codec of choice.
* - On success, the program can access the encoded output with uhdr_get_encoded_stream().
* - The program finishes the encoding with uhdr_release_encoder().
*
* The library allows setting Hdr and/or Sdr intent in compressed format,
* - uhdr_enc_set_compressed_image(ctxt, img, UHDR_HDR_IMG)
* - uhdr_enc_set_compressed_image(ctxt, img, UHDR_SDR_IMG)
* In this mode, the compressed image(s) are first decoded to raw image(s). These raw image(s) go
* through the aforth mentioned gain map computation and encoding process. In this case, the usage
* shall be like this:
* - uhdr_create_encoder()
* - uhdr_enc_set_compressed_image(ctxt, img, UHDR_HDR_IMG)
* - uhdr_enc_set_compressed_image(ctxt, img, UHDR_SDR_IMG)
* - uhdr_encode()
* - uhdr_get_encoded_stream()
* - uhdr_release_encoder()
* If the set compressed image media type of intent UHDR_SDR_IMG and output media type are
* identical, then this image is directly used for primary image. No re-encode of raw image is done.
* This implies base image quality setting is un-used. Only gain map image is encoded at the set
* quality using codec of choice. On the other hand, if the set compressed image media type and
* output media type are different, then transcoding is done.
*
* The library also allows directly setting base and gain map image in compressed format,
* - uhdr_enc_set_compressed_image(ctxt, img, UHDR_BASE_IMG)
* - uhdr_enc_set_gainmap_image(ctxt, img, metadata)
* In this mode, gain map computation is by-passed. The input images are transcoded (if necessary),
* combined and sent back.
*
* It is possible to create a uhdr image solely from Hdr intent. In this case, the usage shall look
* like this:
* - uhdr_create_encoder()
* - uhdr_enc_set_raw_image(ctxt, img, UHDR_HDR_IMG)
* - uhdr_enc_set_quality() // optional
* - uhdr_enc_set_exif_data() // optional
* - uhdr_enc_set_output_format() // optional
* - uhdr_encode()
* - uhdr_get_encoded_stream()
* - uhdr_release_encoder()
* In this mode, the Sdr rendition is created from Hdr intent by tone-mapping. The tone-mapped sdr
* image and hdr image go through the aforth mentioned gain map computation and encoding process to
* create uhdr image.
*
* In all modes, Exif data is inserted if requested.
*
* \param[in] enc encoder instance.
*
* \return uhdr_error_info_t #UHDR_CODEC_OK if operation succeeds, uhdr_codec_err_t otherwise.
*/
UHDR_EXTERN uhdr_error_info_t uhdr_encode(uhdr_codec_private_t* enc);
/*!\brief Get encoded ultra hdr stream
*
* \param[in] enc encoder instance.
*
* \return nullptr if encode process call is unsuccessful, uhdr image descriptor otherwise
*/
UHDR_EXTERN uhdr_compressed_image_t* uhdr_get_encoded_stream(uhdr_codec_private_t* enc);
/*!\brief Reset encoder instance.
* Clears all previous settings and resets to default state and ready for re-initialization
*
* \param[in] enc encoder instance.
*
* \return none
*/
UHDR_EXTERN void uhdr_reset_encoder(uhdr_codec_private_t* enc);
// ===============================================================================================
// Decoder APIs
// ===============================================================================================
/*!\brief check if it is a valid ultrahdr image.
*
* @param[in] data pointer to input compressed stream
* @param[in] size size of compressed stream
*
* @returns 1 if the input data has a primary image, gain map image and gain map metadata. 0
* otherwise.
*/
UHDR_EXTERN int is_uhdr_image(void* data, int size);
/*!\brief Create a new decoder instance. The instance is initialized with default settings.
* To override the settings use uhdr_dec_set_*()
*
* \return nullptr if there was an error allocating memory else a fresh opaque decoder handle
*/
UHDR_EXTERN uhdr_codec_private_t* uhdr_create_decoder(void);
/*!\brief Release decoder instance.
* Frees all allocated storage associated with decoder instance.
*
* \param[in] dec decoder instance.
*
* \return none
*/
UHDR_EXTERN void uhdr_release_decoder(uhdr_codec_private_t* dec);
/*!\brief Add compressed image descriptor to decoder context. The function goes through all the
* fields of the image descriptor and checks for their sanity. If no anomalies are seen then the
* image is added to internal list. Repeated calls to this function will replace the old entry with
* the current.
*
* \param[in] dec decoder instance.
* \param[in] img image descriptor.
*
* \return uhdr_error_info_t #UHDR_CODEC_OK if operation succeeds,
* #UHDR_CODEC_INVALID_PARAM otherwise.
*/
UHDR_EXTERN uhdr_error_info_t uhdr_dec_set_image(uhdr_codec_private_t* dec,
uhdr_compressed_image_t* img);
/*!\brief Set output image format
*
* \param[in] dec decoder instance.
* \param[in] fmt output image format.
*
* \return uhdr_error_info_t #UHDR_CODEC_OK if operation succeeds,
* #UHDR_CODEC_INVALID_PARAM otherwise.
*/
UHDR_EXTERN uhdr_error_info_t uhdr_dec_set_out_img_format(uhdr_codec_private_t* dec,
uhdr_img_fmt_t fmt);
/*!\brief Set output color transfer
*
* \param[in] dec decoder instance.
* \param[in] ct output color transfer
*
* \return uhdr_error_info_t #UHDR_CODEC_OK if operation succeeds,
* #UHDR_CODEC_INVALID_PARAM otherwise.
*/
UHDR_EXTERN uhdr_error_info_t uhdr_dec_set_out_color_transfer(uhdr_codec_private_t* dec,
uhdr_color_transfer_t ct);
/*!\brief Set output max display boost
*
* \param[in] dec decoder instance.
* \param[in] display_boost max display boost
*
* \return uhdr_error_info_t #UHDR_CODEC_OK if operation succeeds,
* #UHDR_CODEC_INVALID_PARAM otherwise.
*/
UHDR_EXTERN uhdr_error_info_t uhdr_dec_set_out_max_display_boost(uhdr_codec_private_t* dec,
float display_boost);
/*!\brief This function parses the bitstream that is registered with the decoder context and makes
* image information available to the client via uhdr_dec_get_() functions. It does not decompress
* the image. That is done by uhdr_decode().
*
* \param[in] dec decoder instance.
*
* \return uhdr_error_info_t #UHDR_CODEC_OK if operation succeeds, uhdr_codec_err_t otherwise.
*/
UHDR_EXTERN uhdr_error_info_t uhdr_dec_probe(uhdr_codec_private_t* dec);
/*!\brief Get base image width
*
* \param[in] dec decoder instance.
*
* \return -1 if probe call is unsuccessful, base image width otherwise
*/
UHDR_EXTERN int uhdr_dec_get_image_width(uhdr_codec_private_t* dec);
/*!\brief Get base image height
*
* \param[in] dec decoder instance.
*
* \return -1 if probe call is unsuccessful, base image height otherwise
*/
UHDR_EXTERN int uhdr_dec_get_image_height(uhdr_codec_private_t* dec);
/*!\brief Get gainmap image width
*
* \param[in] dec decoder instance.
*
* \return -1 if probe call is unsuccessful, gain map image width otherwise
*/
UHDR_EXTERN int uhdr_dec_get_gainmap_width(uhdr_codec_private_t* dec);
/*!\brief Get gainmap image height
*
* \param[in] dec decoder instance.
*
* \return -1 if probe call is unsuccessful, gain map image height otherwise
*/
UHDR_EXTERN int uhdr_dec_get_gainmap_height(uhdr_codec_private_t* dec);
/*!\brief Get exif information
*
* \param[in] dec decoder instance.
*
* \return nullptr if probe call is unsuccessful, memory block with exif data otherwise
*/
UHDR_EXTERN uhdr_mem_block_t* uhdr_dec_get_exif(uhdr_codec_private_t* dec);
/*!\brief Get icc information
*
* \param[in] dec decoder instance.
*
* \return nullptr if probe call is unsuccessful, memory block with icc data otherwise
*/
UHDR_EXTERN uhdr_mem_block_t* uhdr_dec_get_icc(uhdr_codec_private_t* dec);
/*!\brief Get gain map metadata
*
* \param[in] dec decoder instance.
*
* \return nullptr if decoded process call is unsuccessful, gainmap metadata descriptor otherwise
*/
UHDR_EXTERN uhdr_gainmap_metadata_t* uhdr_dec_get_gain_map_metadata(uhdr_codec_private_t* dec);
/*!\brief Decode process call
* After initializing the decoder context, call to this function will submit data for decoding. If
* the call is successful, the decoded output is stored internally and is accessible via
* uhdr_get_decoded_image().
*
* The basic usage of uhdr decoder is as follows:
* - The program creates an instance of a decoder using,
* - uhdr_create_decoder().
* - The program registers input images to the decoder using,
* - uhdr_dec_set_image(ctxt, img)
* - The program overrides the default settings using uhdr_dec_set_*() functions.
* - If the application wants to control the output image format,
* - uhdr_dec_set_out_img_format()
* - If the application wants to control the output transfer characteristics,
* - uhdr_dec_set_out_color_transfer()
* - If the application wants to control the output display boost,
* - uhdr_dec_set_out_max_display_boost()
* - The program calls uhdr_decompress() to decode uhdr stream. This call would initiate the process
* of decoding base image and gain map image. These two are combined to give the final rendition
* image.
* - The program can access the decoded output with uhdr_get_decoded_image().
* - The program finishes the decoding with uhdr_release_decoder().
*
* \param[in] dec decoder instance.
*
* \return uhdr_error_info_t #UHDR_CODEC_OK if operation succeeds, uhdr_codec_err_t otherwise.
*/
UHDR_EXTERN uhdr_error_info_t uhdr_decode(uhdr_codec_private_t* dec);
/*!\brief Get final rendition image
*
* \param[in] dec decoder instance.
*
* \return nullptr if decoded process call is unsuccessful, raw image descriptor otherwise
*/
UHDR_EXTERN uhdr_raw_image_t* uhdr_get_decoded_image(uhdr_codec_private_t* dec);
/*!\brief Get gain map image
*
* \param[in] dec decoder instance.
*
* \return nullptr if decoded process call is unsuccessful, raw image descriptor otherwise
*/
UHDR_EXTERN uhdr_raw_image_t* uhdr_get_gain_map_image(uhdr_codec_private_t* dec);
/*!\brief Reset decoder instance.
* Clears all previous settings and resets to default state and ready for re-initialization
*
* \param[in] dec decoder instance.
*
* \return none
*/
UHDR_EXTERN void uhdr_reset_decoder(uhdr_codec_private_t* dec);
#endif // ULTRAHDR_API_H