[mirror_ubuntu-hirsute-kernel.git] / include / media / v4l2-jpeg.h

/* 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

/**
 * 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 */
};

/**
 * struct v4l2_jpeg_header - parsed JPEG header
 * @sof: pointer to frame header and size
 * @sos: pointer to scan header and size
 * @dht: pointers to huffman tables and sizes
 * @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
 *
 * 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;
};

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);

#endif
Commit	Line	Data
50733b5b PZ	1	/* SPDX-License-Identifier: GPL-2.0-only */
	2	/*
	3	* V4L2 JPEG helpers header
	4	*
	5	* Copyright (C) 2019 Pengutronix, Philipp Zabel <kernel@pengutronix.de>
	6	*
	7	* For reference, see JPEG ITU-T.81 (ISO/IEC 10918-1)
	8	*/
	9
	10	#ifndef _V4L2_JPEG_H
	11	#define _V4L2_JPEG_H
	12
	13	#include <linux/v4l2-controls.h>
	14
	15	#define V4L2_JPEG_MAX_COMPONENTS 4
	16	#define V4L2_JPEG_MAX_TABLES 4
	17
	18	/**
	19	* struct v4l2_jpeg_reference - reference into the JPEG buffer
	20	* @start: pointer to the start of the referenced segment or table
	21	* @length: size of the referenced segment or table
	22	*
	23	* Wnen referencing marker segments, start points right after the marker code,
	24	* and length is the size of the segment parameters, excluding the marker code.
	25	*/
	26	struct v4l2_jpeg_reference {
	27	u8 *start;
	28	size_t length;
	29	};
	30
	31	/* B.2.2 Frame header syntax */
	32
	33	/**
	34	* struct v4l2_jpeg_frame_component_spec - frame component-specification
	35	* @component_identifier: C[i]
	36	* @horizontal_sampling_factor: H[i]
	37	* @vertical_sampling_factor: V[i]
	38	* @quantization_table_selector: quantization table destination selector Tq[i]
	39	*/
	40	struct v4l2_jpeg_frame_component_spec {
	41	u8 component_identifier;
	42	u8 horizontal_sampling_factor;
	43	u8 vertical_sampling_factor;
	44	u8 quantization_table_selector;
	45	};
	46
	47	/**
	48	* struct v4l2_jpeg_frame_header - JPEG frame header
	49	* @height: Y
	50	* @width: X
	51	* @precision: P
	52	* @num_components: Nf
	53	* @component: component-specification, see v4l2_jpeg_frame_component_spec
	54	* @subsampling: decoded subsampling from component-specification
	55	*/
	56	struct v4l2_jpeg_frame_header {
	57	u16 height;
	58	u16 width;
	59	u8 precision;
	60	u8 num_components;
	61	struct v4l2_jpeg_frame_component_spec component[V4L2_JPEG_MAX_COMPONENTS];
	62	enum v4l2_jpeg_chroma_subsampling subsampling;
	63	};
	64
65	/* B.2.3 Scan header syntax */
66
67	/**
68	* struct v4l2_jpeg_scan_component_spec - scan component-specification
69	* @component_selector: Cs[j]
70	* @dc_entropy_coding_table_selector: Td[j]
71	* @ac_entropy_coding_table_selector: Ta[j]
72	*/
73	struct v4l2_jpeg_scan_component_spec {
74	u8 component_selector;
75	u8 dc_entropy_coding_table_selector;
76	u8 ac_entropy_coding_table_selector;
77	};
78
79	/**
80	* struct v4l2_jpeg_scan_header - JPEG scan header
81	* @num_components: Ns
82	* @component: component-specification, see v4l2_jpeg_scan_component_spec
83	*/
84	struct v4l2_jpeg_scan_header {
85	u8 num_components; /* Ns */
86	struct v4l2_jpeg_scan_component_spec component[V4L2_JPEG_MAX_COMPONENTS];
87	/* Ss, Se, Ah, and Al are not used by any driver */
88	};
89
90	/**
91	* struct v4l2_jpeg_header - parsed JPEG header
92	* @sof: pointer to frame header and size
93	* @sos: pointer to scan header and size
94	* @dht: pointers to huffman tables and sizes
95	* @dqt: pointers to quantization tables and sizes
96	* @frame: parsed frame header
97	* @scan: pointer to parsed scan header, optional
98	* @quantization_tables: references to four quantization tables, optional
99	* @huffman_tables: references to four Huffman tables in DC0, DC1, AC0, AC1
100	* order, optional
101	* @restart_interval: number of MCU per restart interval, Ri
102	* @ecs_offset: buffer offset in bytes to the entropy coded segment
103	*
104	* When this structure is passed to v4l2_jpeg_parse_header, the optional scan,
105	* quantization_tables, and huffman_tables pointers must be initialized to NULL
106	* or point at valid memory.
107	*/
108	struct v4l2_jpeg_header {
109	struct v4l2_jpeg_reference sof;
110	struct v4l2_jpeg_reference sos;
111	unsigned int num_dht;
112	struct v4l2_jpeg_reference dht[V4L2_JPEG_MAX_TABLES];
113	unsigned int num_dqt;
114	struct v4l2_jpeg_reference dqt[V4L2_JPEG_MAX_TABLES];
115
116	struct v4l2_jpeg_frame_header frame;
117	struct v4l2_jpeg_scan_header *scan;
118	struct v4l2_jpeg_reference *quantization_tables;
119	struct v4l2_jpeg_reference *huffman_tables;
120	u16 restart_interval;
121	size_t ecs_offset;
122	};
123
124	int v4l2_jpeg_parse_header(void buf, size_t len, struct v4l2_jpeg_header out);
125
126	int v4l2_jpeg_parse_frame_header(void *buf, size_t len,
127	struct v4l2_jpeg_frame_header *frame_header);
128	int v4l2_jpeg_parse_scan_header(void *buf, size_t len,
129	struct v4l2_jpeg_scan_header *scan_header);
130	int v4l2_jpeg_parse_quantization_tables(void *buf, size_t len, u8 precision,
131	struct v4l2_jpeg_reference *q_tables);
132	int v4l2_jpeg_parse_huffman_tables(void *buf, size_t len,
133	struct v4l2_jpeg_reference *huffman_tables);
134
135	#endif