include/media/v4l2-jpeg.h - linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
  * V4L2 JPEG helpers header
  *
  * Copyright (C) 2019 Pengutronix, Philipp Zabel <kernel@pengutronix.de>
  *
  * For reference, see JPEG ITU-T.81 (ISO/IEC 10918-1)
  */

 #ifndef _V4L2_JPEG_H
 #define _V4L2_JPEG_H

 #include <linux/v4l2-controls.h>

 #define V4L2_JPEG_MAX_COMPONENTS	4
 #define V4L2_JPEG_MAX_TABLES		4
 /*
  * Prefixes used to generate huffman table class and destination identifiers as
  * described below:
  *
  * V4L2_JPEG_LUM_HT | V4L2_JPEG_DC_HT : Prefix for Luma DC coefficients
  *					huffman table
  * V4L2_JPEG_LUM_HT | V4L2_JPEG_AC_HT : Prefix for Luma AC coefficients
  *					huffman table
  * V4L2_JPEG_CHR_HT | V4L2_JPEG_DC_HT : Prefix for Chroma DC coefficients
  *					huffman table
  * V4L2_JPEG_CHR_HT | V4L2_JPEG_AC_HT : Prefix for Chroma AC coefficients
  *					huffman table
  */
 #define V4L2_JPEG_LUM_HT		0x00
 #define V4L2_JPEG_CHR_HT		0x01
 #define V4L2_JPEG_DC_HT			0x00
 #define V4L2_JPEG_AC_HT			0x10

 /* Length of reference huffman tables as provided in Table K.3 of ITU-T.81 */
 #define V4L2_JPEG_REF_HT_AC_LEN		178
 #define V4L2_JPEG_REF_HT_DC_LEN		28

 /* Array size for 8x8 block of samples or DCT coefficient */
 #define V4L2_JPEG_PIXELS_IN_BLOCK	64

 /**
  * struct v4l2_jpeg_reference - reference into the JPEG buffer
  * @start: pointer to the start of the referenced segment or table
  * @length: size of the referenced segment or table
  *
  * Wnen referencing marker segments, start points right after the marker code,
  * and length is the size of the segment parameters, excluding the marker code.
  */
 struct v4l2_jpeg_reference {
 	u8 *start;
 	size_t length;
 };

 /* B.2.2 Frame header syntax */

 /**
  * struct v4l2_jpeg_frame_component_spec - frame component-specification
  * @component_identifier: C[i]
  * @horizontal_sampling_factor: H[i]
  * @vertical_sampling_factor: V[i]
  * @quantization_table_selector: quantization table destination selector Tq[i]
  */
 struct v4l2_jpeg_frame_component_spec {
 	u8 component_identifier;
 	u8 horizontal_sampling_factor;
 	u8 vertical_sampling_factor;
 	u8 quantization_table_selector;
 };

 /**
  * struct v4l2_jpeg_frame_header - JPEG frame header
  * @height: Y
  * @width: X
  * @precision: P
  * @num_components: Nf
  * @component: component-specification, see v4l2_jpeg_frame_component_spec
  * @subsampling: decoded subsampling from component-specification
  */
 struct v4l2_jpeg_frame_header {
 	u16 height;
 	u16 width;
 	u8 precision;
 	u8 num_components;
 	struct v4l2_jpeg_frame_component_spec component[V4L2_JPEG_MAX_COMPONENTS];
 	enum v4l2_jpeg_chroma_subsampling subsampling;
 };

 /* B.2.3 Scan header syntax */

 /**
  * struct v4l2_jpeg_scan_component_spec - scan component-specification
  * @component_selector: Cs[j]
  * @dc_entropy_coding_table_selector: Td[j]
  * @ac_entropy_coding_table_selector: Ta[j]
  */
 struct v4l2_jpeg_scan_component_spec {
 	u8 component_selector;
 	u8 dc_entropy_coding_table_selector;
 	u8 ac_entropy_coding_table_selector;
 };

 /**
  * struct v4l2_jpeg_scan_header - JPEG scan header
  * @num_components: Ns
  * @component: component-specification, see v4l2_jpeg_scan_component_spec
  */
 struct v4l2_jpeg_scan_header {
 	u8 num_components;				/* Ns */
 	struct v4l2_jpeg_scan_component_spec component[V4L2_JPEG_MAX_COMPONENTS];
 	/* Ss, Se, Ah, and Al are not used by any driver */
 };

 /**
  * enum v4l2_jpeg_app14_tf - APP14 transform flag
  * According to Rec. ITU-T T.872 (06/2012) 6.5.3
  * APP14 segment is for color encoding, it contains a transform flag,
  * which may have values of 0, 1 and 2 and are interpreted as follows:
  * @V4L2_JPEG_APP14_TF_CMYK_RGB: CMYK for images encoded with four components
  *                               RGB for images encoded with three components
  * @V4L2_JPEG_APP14_TF_YCBCR: an image encoded with three components using YCbCr
  * @V4L2_JPEG_APP14_TF_YCCK: an image encoded with four components using YCCK
  * @V4L2_JPEG_APP14_TF_UNKNOWN: indicate app14 is not present
  */
 enum v4l2_jpeg_app14_tf {
 	V4L2_JPEG_APP14_TF_CMYK_RGB	= 0,
 	V4L2_JPEG_APP14_TF_YCBCR	= 1,
 	V4L2_JPEG_APP14_TF_YCCK		= 2,
 	V4L2_JPEG_APP14_TF_UNKNOWN	= -1,
 };

 /**
  * struct v4l2_jpeg_header - parsed JPEG header
  * @sof: pointer to frame header and size
  * @sos: pointer to scan header and size
  * @num_dht: number of entries in @dht
  * @dht: pointers to huffman tables and sizes
  * @num_dqt: number of entries in @dqt
  * @dqt: pointers to quantization tables and sizes
  * @frame: parsed frame header
  * @scan: pointer to parsed scan header, optional
  * @quantization_tables: references to four quantization tables, optional
  * @huffman_tables: references to four Huffman tables in DC0, DC1, AC0, AC1
  *                  order, optional
  * @restart_interval: number of MCU per restart interval, Ri
  * @ecs_offset: buffer offset in bytes to the entropy coded segment
  * @app14_tf: transform flag from app14 data
  *
  * When this structure is passed to v4l2_jpeg_parse_header, the optional scan,
  * quantization_tables, and huffman_tables pointers must be initialized to NULL
  * or point at valid memory.
  */
 struct v4l2_jpeg_header {
 	struct v4l2_jpeg_reference sof;
 	struct v4l2_jpeg_reference sos;
 	unsigned int num_dht;
 	struct v4l2_jpeg_reference dht[V4L2_JPEG_MAX_TABLES];
 	unsigned int num_dqt;
 	struct v4l2_jpeg_reference dqt[V4L2_JPEG_MAX_TABLES];

 	struct v4l2_jpeg_frame_header frame;
 	struct v4l2_jpeg_scan_header *scan;
 	struct v4l2_jpeg_reference *quantization_tables;
 	struct v4l2_jpeg_reference *huffman_tables;
 	u16 restart_interval;
 	size_t ecs_offset;
 	enum v4l2_jpeg_app14_tf app14_tf;
 };

 int v4l2_jpeg_parse_header(void *buf, size_t len, struct v4l2_jpeg_header *out);

 int v4l2_jpeg_parse_frame_header(void *buf, size_t len,
 				 struct v4l2_jpeg_frame_header *frame_header);
 int v4l2_jpeg_parse_scan_header(void *buf, size_t len,
 				struct v4l2_jpeg_scan_header *scan_header);
 int v4l2_jpeg_parse_quantization_tables(void *buf, size_t len, u8 precision,
 					struct v4l2_jpeg_reference *q_tables);
 int v4l2_jpeg_parse_huffman_tables(void *buf, size_t len,
 				   struct v4l2_jpeg_reference *huffman_tables);

 extern const u8 v4l2_jpeg_zigzag_scan_index[V4L2_JPEG_PIXELS_IN_BLOCK];
 extern const u8 v4l2_jpeg_ref_table_luma_qt[V4L2_JPEG_PIXELS_IN_BLOCK];
 extern const u8 v4l2_jpeg_ref_table_chroma_qt[V4L2_JPEG_PIXELS_IN_BLOCK];
 extern const u8 v4l2_jpeg_ref_table_luma_dc_ht[V4L2_JPEG_REF_HT_DC_LEN];
 extern const u8 v4l2_jpeg_ref_table_luma_ac_ht[V4L2_JPEG_REF_HT_AC_LEN];
 extern const u8 v4l2_jpeg_ref_table_chroma_dc_ht[V4L2_JPEG_REF_HT_DC_LEN];
 extern const u8 v4l2_jpeg_ref_table_chroma_ac_ht[V4L2_JPEG_REF_HT_AC_LEN];

 #endif
	/* SPDX-License-Identifier: GPL-2.0-only */
	/*
	* V4L2 JPEG helpers header
	*
	* Copyright (C) 2019 Pengutronix, Philipp Zabel <kernel@pengutronix.de>
	*
	* For reference, see JPEG ITU-T.81 (ISO/IEC 10918-1)
	*/

	#ifndef _V4L2_JPEG_H
	#define _V4L2_JPEG_H

	#include <linux/v4l2-controls.h>

	#define V4L2_JPEG_MAX_COMPONENTS 4
	#define V4L2_JPEG_MAX_TABLES 4
	/*
	* Prefixes used to generate huffman table class and destination identifiers as
	* described below:
	*
	* V4L2_JPEG_LUM_HT \| V4L2_JPEG_DC_HT : Prefix for Luma DC coefficients
	* huffman table
	* V4L2_JPEG_LUM_HT \| V4L2_JPEG_AC_HT : Prefix for Luma AC coefficients
	* huffman table
	* V4L2_JPEG_CHR_HT \| V4L2_JPEG_DC_HT : Prefix for Chroma DC coefficients
	* huffman table
	* V4L2_JPEG_CHR_HT \| V4L2_JPEG_AC_HT : Prefix for Chroma AC coefficients
	* huffman table
	*/
	#define V4L2_JPEG_LUM_HT 0x00
	#define V4L2_JPEG_CHR_HT 0x01
	#define V4L2_JPEG_DC_HT 0x00
	#define V4L2_JPEG_AC_HT 0x10

	/* Length of reference huffman tables as provided in Table K.3 of ITU-T.81 */
	#define V4L2_JPEG_REF_HT_AC_LEN 178
	#define V4L2_JPEG_REF_HT_DC_LEN 28

	/* Array size for 8x8 block of samples or DCT coefficient */
	#define V4L2_JPEG_PIXELS_IN_BLOCK 64

	/**
	* struct v4l2_jpeg_reference - reference into the JPEG buffer
	* @start: pointer to the start of the referenced segment or table
	* @length: size of the referenced segment or table
	*
	* Wnen referencing marker segments, start points right after the marker code,
	* and length is the size of the segment parameters, excluding the marker code.
	*/
	struct v4l2_jpeg_reference {
	u8 *start;
	size_t length;
	};

	/* B.2.2 Frame header syntax */

	/**
	* struct v4l2_jpeg_frame_component_spec - frame component-specification
	* @component_identifier: C[i]
	* @horizontal_sampling_factor: H[i]
	* @vertical_sampling_factor: V[i]
	* @quantization_table_selector: quantization table destination selector Tq[i]
	*/
	struct v4l2_jpeg_frame_component_spec {
	u8 component_identifier;
	u8 horizontal_sampling_factor;
	u8 vertical_sampling_factor;
	u8 quantization_table_selector;
	};

	/**
	* struct v4l2_jpeg_frame_header - JPEG frame header
	* @height: Y
	* @width: X
	* @precision: P
	* @num_components: Nf
	* @component: component-specification, see v4l2_jpeg_frame_component_spec
	* @subsampling: decoded subsampling from component-specification
	*/
	struct v4l2_jpeg_frame_header {
	u16 height;
	u16 width;
	u8 precision;
	u8 num_components;
	struct v4l2_jpeg_frame_component_spec component[V4L2_JPEG_MAX_COMPONENTS];
	enum v4l2_jpeg_chroma_subsampling subsampling;
	};

	/* B.2.3 Scan header syntax */

	/**
	* struct v4l2_jpeg_scan_component_spec - scan component-specification
	* @component_selector: Cs[j]
	* @dc_entropy_coding_table_selector: Td[j]
	* @ac_entropy_coding_table_selector: Ta[j]
	*/
	struct v4l2_jpeg_scan_component_spec {
	u8 component_selector;
	u8 dc_entropy_coding_table_selector;
	u8 ac_entropy_coding_table_selector;
	};

	/**
	* struct v4l2_jpeg_scan_header - JPEG scan header
	* @num_components: Ns
	* @component: component-specification, see v4l2_jpeg_scan_component_spec
	*/
	struct v4l2_jpeg_scan_header {
	u8 num_components; /* Ns */
	struct v4l2_jpeg_scan_component_spec component[V4L2_JPEG_MAX_COMPONENTS];
	/* Ss, Se, Ah, and Al are not used by any driver */
	};

	/**
	* enum v4l2_jpeg_app14_tf - APP14 transform flag
	* According to Rec. ITU-T T.872 (06/2012) 6.5.3
	* APP14 segment is for color encoding, it contains a transform flag,
	* which may have values of 0, 1 and 2 and are interpreted as follows:
	* @V4L2_JPEG_APP14_TF_CMYK_RGB: CMYK for images encoded with four components
	* RGB for images encoded with three components
	* @V4L2_JPEG_APP14_TF_YCBCR: an image encoded with three components using YCbCr
	* @V4L2_JPEG_APP14_TF_YCCK: an image encoded with four components using YCCK
	* @V4L2_JPEG_APP14_TF_UNKNOWN: indicate app14 is not present
	*/
	enum v4l2_jpeg_app14_tf {
	V4L2_JPEG_APP14_TF_CMYK_RGB = 0,
	V4L2_JPEG_APP14_TF_YCBCR = 1,
	V4L2_JPEG_APP14_TF_YCCK = 2,
	V4L2_JPEG_APP14_TF_UNKNOWN = -1,
	};

	/**
	* struct v4l2_jpeg_header - parsed JPEG header
	* @sof: pointer to frame header and size
	* @sos: pointer to scan header and size
	* @num_dht: number of entries in @dht
	* @dht: pointers to huffman tables and sizes
	* @num_dqt: number of entries in @dqt
	* @dqt: pointers to quantization tables and sizes
	* @frame: parsed frame header
	* @scan: pointer to parsed scan header, optional
	* @quantization_tables: references to four quantization tables, optional
	* @huffman_tables: references to four Huffman tables in DC0, DC1, AC0, AC1
	* order, optional
	* @restart_interval: number of MCU per restart interval, Ri
	* @ecs_offset: buffer offset in bytes to the entropy coded segment
	* @app14_tf: transform flag from app14 data
	*
	* When this structure is passed to v4l2_jpeg_parse_header, the optional scan,
	* quantization_tables, and huffman_tables pointers must be initialized to NULL
	* or point at valid memory.
	*/
	struct v4l2_jpeg_header {
	struct v4l2_jpeg_reference sof;
	struct v4l2_jpeg_reference sos;
	unsigned int num_dht;
	struct v4l2_jpeg_reference dht[V4L2_JPEG_MAX_TABLES];
	unsigned int num_dqt;
	struct v4l2_jpeg_reference dqt[V4L2_JPEG_MAX_TABLES];

	struct v4l2_jpeg_frame_header frame;
	struct v4l2_jpeg_scan_header *scan;
	struct v4l2_jpeg_reference *quantization_tables;
	struct v4l2_jpeg_reference *huffman_tables;
	u16 restart_interval;
	size_t ecs_offset;
	enum v4l2_jpeg_app14_tf app14_tf;
	};

	int v4l2_jpeg_parse_header(void buf, size_t len, struct v4l2_jpeg_header out);

	int v4l2_jpeg_parse_frame_header(void *buf, size_t len,
	struct v4l2_jpeg_frame_header *frame_header);
	int v4l2_jpeg_parse_scan_header(void *buf, size_t len,
	struct v4l2_jpeg_scan_header *scan_header);
	int v4l2_jpeg_parse_quantization_tables(void *buf, size_t len, u8 precision,
	struct v4l2_jpeg_reference *q_tables);
	int v4l2_jpeg_parse_huffman_tables(void *buf, size_t len,
	struct v4l2_jpeg_reference *huffman_tables);

	extern const u8 v4l2_jpeg_zigzag_scan_index[V4L2_JPEG_PIXELS_IN_BLOCK];
	extern const u8 v4l2_jpeg_ref_table_luma_qt[V4L2_JPEG_PIXELS_IN_BLOCK];
	extern const u8 v4l2_jpeg_ref_table_chroma_qt[V4L2_JPEG_PIXELS_IN_BLOCK];
	extern const u8 v4l2_jpeg_ref_table_luma_dc_ht[V4L2_JPEG_REF_HT_DC_LEN];
	extern const u8 v4l2_jpeg_ref_table_luma_ac_ht[V4L2_JPEG_REF_HT_AC_LEN];
	extern const u8 v4l2_jpeg_ref_table_chroma_dc_ht[V4L2_JPEG_REF_HT_DC_LEN];
	extern const u8 v4l2_jpeg_ref_table_chroma_ac_ht[V4L2_JPEG_REF_HT_AC_LEN];

	#endif