1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0-only */ 2*4882a593Smuzhiyun /* 3*4882a593Smuzhiyun * V4L2 JPEG helpers header 4*4882a593Smuzhiyun * 5*4882a593Smuzhiyun * Copyright (C) 2019 Pengutronix, Philipp Zabel <kernel@pengutronix.de> 6*4882a593Smuzhiyun * 7*4882a593Smuzhiyun * For reference, see JPEG ITU-T.81 (ISO/IEC 10918-1) 8*4882a593Smuzhiyun */ 9*4882a593Smuzhiyun 10*4882a593Smuzhiyun #ifndef _V4L2_JPEG_H 11*4882a593Smuzhiyun #define _V4L2_JPEG_H 12*4882a593Smuzhiyun 13*4882a593Smuzhiyun #include <linux/v4l2-controls.h> 14*4882a593Smuzhiyun 15*4882a593Smuzhiyun #define V4L2_JPEG_MAX_COMPONENTS 4 16*4882a593Smuzhiyun #define V4L2_JPEG_MAX_TABLES 4 17*4882a593Smuzhiyun 18*4882a593Smuzhiyun /** 19*4882a593Smuzhiyun * struct v4l2_jpeg_reference - reference into the JPEG buffer 20*4882a593Smuzhiyun * @start: pointer to the start of the referenced segment or table 21*4882a593Smuzhiyun * @length: size of the referenced segment or table 22*4882a593Smuzhiyun * 23*4882a593Smuzhiyun * Wnen referencing marker segments, start points right after the marker code, 24*4882a593Smuzhiyun * and length is the size of the segment parameters, excluding the marker code. 25*4882a593Smuzhiyun */ 26*4882a593Smuzhiyun struct v4l2_jpeg_reference { 27*4882a593Smuzhiyun u8 *start; 28*4882a593Smuzhiyun size_t length; 29*4882a593Smuzhiyun }; 30*4882a593Smuzhiyun 31*4882a593Smuzhiyun /* B.2.2 Frame header syntax */ 32*4882a593Smuzhiyun 33*4882a593Smuzhiyun /** 34*4882a593Smuzhiyun * struct v4l2_jpeg_frame_component_spec - frame component-specification 35*4882a593Smuzhiyun * @component_identifier: C[i] 36*4882a593Smuzhiyun * @horizontal_sampling_factor: H[i] 37*4882a593Smuzhiyun * @vertical_sampling_factor: V[i] 38*4882a593Smuzhiyun * @quantization_table_selector: quantization table destination selector Tq[i] 39*4882a593Smuzhiyun */ 40*4882a593Smuzhiyun struct v4l2_jpeg_frame_component_spec { 41*4882a593Smuzhiyun u8 component_identifier; 42*4882a593Smuzhiyun u8 horizontal_sampling_factor; 43*4882a593Smuzhiyun u8 vertical_sampling_factor; 44*4882a593Smuzhiyun u8 quantization_table_selector; 45*4882a593Smuzhiyun }; 46*4882a593Smuzhiyun 47*4882a593Smuzhiyun /** 48*4882a593Smuzhiyun * struct v4l2_jpeg_frame_header - JPEG frame header 49*4882a593Smuzhiyun * @height: Y 50*4882a593Smuzhiyun * @width: X 51*4882a593Smuzhiyun * @precision: P 52*4882a593Smuzhiyun * @num_components: Nf 53*4882a593Smuzhiyun * @component: component-specification, see v4l2_jpeg_frame_component_spec 54*4882a593Smuzhiyun * @subsampling: decoded subsampling from component-specification 55*4882a593Smuzhiyun */ 56*4882a593Smuzhiyun struct v4l2_jpeg_frame_header { 57*4882a593Smuzhiyun u16 height; 58*4882a593Smuzhiyun u16 width; 59*4882a593Smuzhiyun u8 precision; 60*4882a593Smuzhiyun u8 num_components; 61*4882a593Smuzhiyun struct v4l2_jpeg_frame_component_spec component[V4L2_JPEG_MAX_COMPONENTS]; 62*4882a593Smuzhiyun enum v4l2_jpeg_chroma_subsampling subsampling; 63*4882a593Smuzhiyun }; 64*4882a593Smuzhiyun 65*4882a593Smuzhiyun /* B.2.3 Scan header syntax */ 66*4882a593Smuzhiyun 67*4882a593Smuzhiyun /** 68*4882a593Smuzhiyun * struct v4l2_jpeg_scan_component_spec - scan component-specification 69*4882a593Smuzhiyun * @component_selector: Cs[j] 70*4882a593Smuzhiyun * @dc_entropy_coding_table_selector: Td[j] 71*4882a593Smuzhiyun * @ac_entropy_coding_table_selector: Ta[j] 72*4882a593Smuzhiyun */ 73*4882a593Smuzhiyun struct v4l2_jpeg_scan_component_spec { 74*4882a593Smuzhiyun u8 component_selector; 75*4882a593Smuzhiyun u8 dc_entropy_coding_table_selector; 76*4882a593Smuzhiyun u8 ac_entropy_coding_table_selector; 77*4882a593Smuzhiyun }; 78*4882a593Smuzhiyun 79*4882a593Smuzhiyun /** 80*4882a593Smuzhiyun * struct v4l2_jpeg_scan_header - JPEG scan header 81*4882a593Smuzhiyun * @num_components: Ns 82*4882a593Smuzhiyun * @component: component-specification, see v4l2_jpeg_scan_component_spec 83*4882a593Smuzhiyun */ 84*4882a593Smuzhiyun struct v4l2_jpeg_scan_header { 85*4882a593Smuzhiyun u8 num_components; /* Ns */ 86*4882a593Smuzhiyun struct v4l2_jpeg_scan_component_spec component[V4L2_JPEG_MAX_COMPONENTS]; 87*4882a593Smuzhiyun /* Ss, Se, Ah, and Al are not used by any driver */ 88*4882a593Smuzhiyun }; 89*4882a593Smuzhiyun 90*4882a593Smuzhiyun /** 91*4882a593Smuzhiyun * struct v4l2_jpeg_header - parsed JPEG header 92*4882a593Smuzhiyun * @sof: pointer to frame header and size 93*4882a593Smuzhiyun * @sos: pointer to scan header and size 94*4882a593Smuzhiyun * @dht: pointers to huffman tables and sizes 95*4882a593Smuzhiyun * @dqt: pointers to quantization tables and sizes 96*4882a593Smuzhiyun * @frame: parsed frame header 97*4882a593Smuzhiyun * @scan: pointer to parsed scan header, optional 98*4882a593Smuzhiyun * @quantization_tables: references to four quantization tables, optional 99*4882a593Smuzhiyun * @huffman_tables: references to four Huffman tables in DC0, DC1, AC0, AC1 100*4882a593Smuzhiyun * order, optional 101*4882a593Smuzhiyun * @restart_interval: number of MCU per restart interval, Ri 102*4882a593Smuzhiyun * @ecs_offset: buffer offset in bytes to the entropy coded segment 103*4882a593Smuzhiyun * 104*4882a593Smuzhiyun * When this structure is passed to v4l2_jpeg_parse_header, the optional scan, 105*4882a593Smuzhiyun * quantization_tables, and huffman_tables pointers must be initialized to NULL 106*4882a593Smuzhiyun * or point at valid memory. 107*4882a593Smuzhiyun */ 108*4882a593Smuzhiyun struct v4l2_jpeg_header { 109*4882a593Smuzhiyun struct v4l2_jpeg_reference sof; 110*4882a593Smuzhiyun struct v4l2_jpeg_reference sos; 111*4882a593Smuzhiyun unsigned int num_dht; 112*4882a593Smuzhiyun struct v4l2_jpeg_reference dht[V4L2_JPEG_MAX_TABLES]; 113*4882a593Smuzhiyun unsigned int num_dqt; 114*4882a593Smuzhiyun struct v4l2_jpeg_reference dqt[V4L2_JPEG_MAX_TABLES]; 115*4882a593Smuzhiyun 116*4882a593Smuzhiyun struct v4l2_jpeg_frame_header frame; 117*4882a593Smuzhiyun struct v4l2_jpeg_scan_header *scan; 118*4882a593Smuzhiyun struct v4l2_jpeg_reference *quantization_tables; 119*4882a593Smuzhiyun struct v4l2_jpeg_reference *huffman_tables; 120*4882a593Smuzhiyun u16 restart_interval; 121*4882a593Smuzhiyun size_t ecs_offset; 122*4882a593Smuzhiyun }; 123*4882a593Smuzhiyun 124*4882a593Smuzhiyun int v4l2_jpeg_parse_header(void *buf, size_t len, struct v4l2_jpeg_header *out); 125*4882a593Smuzhiyun 126*4882a593Smuzhiyun int v4l2_jpeg_parse_frame_header(void *buf, size_t len, 127*4882a593Smuzhiyun struct v4l2_jpeg_frame_header *frame_header); 128*4882a593Smuzhiyun int v4l2_jpeg_parse_scan_header(void *buf, size_t len, 129*4882a593Smuzhiyun struct v4l2_jpeg_scan_header *scan_header); 130*4882a593Smuzhiyun int v4l2_jpeg_parse_quantization_tables(void *buf, size_t len, u8 precision, 131*4882a593Smuzhiyun struct v4l2_jpeg_reference *q_tables); 132*4882a593Smuzhiyun int v4l2_jpeg_parse_huffman_tables(void *buf, size_t len, 133*4882a593Smuzhiyun struct v4l2_jpeg_reference *huffman_tables); 134*4882a593Smuzhiyun 135*4882a593Smuzhiyun #endif 136