media: v4l2-jpeg: Export reference quantization and huffman tables

Export reference quantization and huffman tables as provided in ITU-T.81 so
that they can be re-used by other JPEG drivers.

These are example tables provided in ITU-T.81 as reference tables and the
JPEG encoders are free to use either these or their own proprietary tables.

Also add necessary prefixes to be used for huffman tables in global header
file.

Signed-off-by: Devarsh Thakkar <[e-mail]>
Reviewed-by: Hans Verkuil <[e-mail]>
Signed-off-by: Sebastian Fricke <[e-mail]>
Signed-off-by: Hans Verkuil <[e-mail]>

drivers/media/v4l2-core/v4l2-jpeg.c

···
 #define COM	0xfffe	/* comment */
 #define TEM	0xff01	/* temporary */
 
+/* Luma and chroma qp tables to achieve 50% compression quality
+ * This is as per example in Annex K.1 of ITU-T.81
+ */
+const u8 v4l2_jpeg_ref_table_luma_qt[V4L2_JPEG_PIXELS_IN_BLOCK] = {
+	16, 11, 10, 16, 24, 40, 51, 61,
+	12, 12, 14, 19, 26, 58, 60, 55,
+	14, 13, 16, 24, 40, 57, 69, 56,
+	14, 17, 22, 29, 51, 87, 80, 62,
+	18, 22, 37, 56, 68, 109, 103, 77,
+	24, 35, 55, 64, 81, 104, 113, 92,
+	49, 64, 78, 87, 103, 121, 120, 101,
+	72, 92, 95, 98, 112, 100, 103, 99
+};
+EXPORT_SYMBOL_GPL(v4l2_jpeg_ref_table_luma_qt);
+
+const u8 v4l2_jpeg_ref_table_chroma_qt[V4L2_JPEG_PIXELS_IN_BLOCK] = {
+	17, 18, 24, 47, 99, 99, 99, 99,
+	18, 21, 26, 66, 99, 99, 99, 99,
+	24, 26, 56, 99, 99, 99, 99, 99,
+	47, 66, 99, 99, 99, 99, 99, 99,
+	99, 99, 99, 99, 99, 99, 99, 99,
+	99, 99, 99, 99, 99, 99, 99, 99,
+	99, 99, 99, 99, 99, 99, 99, 99,
+	99, 99, 99, 99, 99, 99, 99, 99
+};
+EXPORT_SYMBOL_GPL(v4l2_jpeg_ref_table_chroma_qt);
+
+/* Zigzag scan pattern indexes */
+const u8 v4l2_jpeg_zigzag_scan_index[V4L2_JPEG_PIXELS_IN_BLOCK] = {
+	0,   1,  8, 16,  9,  2,  3, 10,
+	17, 24, 32, 25, 18, 11,  4,  5,
+	12, 19, 26, 33, 40, 48, 41, 34,
+	27, 20, 13,  6,  7, 14, 21, 28,
+	35, 42, 49, 56, 57, 50, 43, 36,
+	29, 22, 15, 23, 30, 37, 44, 51,
+	58, 59, 52, 45, 38, 31, 39, 46,
+	53, 60, 61, 54, 47, 55, 62, 63
+};
+EXPORT_SYMBOL_GPL(v4l2_jpeg_zigzag_scan_index);
+
+/*
+ * Contains the data that needs to be sent in the marker segment of an
+ * interchange format JPEG stream or an abbreviated format table specification
+ * data stream. Specifies the huffman table used for encoding the luminance DC
+ * coefficient differences. The table represents Table K.3 of ITU-T.81
+ */
+const u8 v4l2_jpeg_ref_table_luma_dc_ht[V4L2_JPEG_REF_HT_DC_LEN] = {
+	0x00, 0x01, 0x05, 0x01, 0x01, 0x01, 0x01, 0x01,
+	0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B
+};
+EXPORT_SYMBOL_GPL(v4l2_jpeg_ref_table_luma_dc_ht);
+
+/*
+ * Contains the data that needs to be sent in the marker segment of an
+ * interchange format JPEG stream or an abbreviated format table specification
+ * data stream. Specifies the huffman table used for encoding the luminance AC
+ * coefficients. The table represents Table K.5 of ITU-T.81
+ */
+const u8 v4l2_jpeg_ref_table_luma_ac_ht[V4L2_JPEG_REF_HT_AC_LEN] = {
+	0x00, 0x02, 0x01, 0x03, 0x03, 0x02, 0x04, 0x03, 0x05, 0x05, 0x04, 0x04,
+	0x00, 0x00, 0x01, 0x7D, 0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12,
+	0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07, 0x22, 0x71, 0x14, 0x32,
+	0x81, 0x91, 0xA1, 0x08, 0x23, 0x42, 0xB1, 0xC1, 0x15, 0x52, 0xD1, 0xF0,
+	0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0A, 0x16, 0x17, 0x18, 0x19, 0x1A,
+	0x25, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,
+	0x3A, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4A, 0x53, 0x54, 0x55,
+	0x56, 0x57, 0x58, 0x59, 0x5A, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,
+	0x6A, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A, 0x83, 0x84, 0x85,
+	0x86, 0x87, 0x88, 0x89, 0x8A, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,
+	0x99, 0x9A, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xB2,
+	0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xC2, 0xC3, 0xC4, 0xC5,
+	0xC6, 0xC7, 0xC8, 0xC9, 0xCA, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8,
+	0xD9, 0xDA, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8, 0xE9, 0xEA,
+	0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7, 0xF8, 0xF9, 0xFA
+};
+EXPORT_SYMBOL_GPL(v4l2_jpeg_ref_table_luma_ac_ht);
+
+/*
+ * Contains the data that needs to be sent in the marker segment of an interchange format JPEG
+ * stream or an abbreviated format table specification data stream.
+ * Specifies the huffman table used for encoding the chrominance DC coefficient differences.
+ * The table represents Table K.4 of ITU-T.81
+ */
+const u8 v4l2_jpeg_ref_table_chroma_dc_ht[V4L2_JPEG_REF_HT_DC_LEN] = {
+	0x00, 0x03, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+	0x01, 0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B
+};
+EXPORT_SYMBOL_GPL(v4l2_jpeg_ref_table_chroma_dc_ht);
+
+/*
+ * Contains the data that needs to be sent in the marker segment of an
+ * interchange format JPEG stream or an abbreviated format table specification
+ * data stream. Specifies the huffman table used for encoding the chrominance
+ * AC coefficients. The table represents Table K.6 of ITU-T.81
+ */
+const u8 v4l2_jpeg_ref_table_chroma_ac_ht[V4L2_JPEG_REF_HT_AC_LEN] = {
+	0x00, 0x02, 0x01, 0x02, 0x04, 0x04, 0x03, 0x04, 0x07, 0x05, 0x04, 0x04,
+	0x00, 0x01, 0x02, 0x77, 0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21,
+	0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71, 0x13, 0x22, 0x32, 0x81,
+	0x08, 0x14, 0x42, 0x91, 0xA1, 0xB1, 0xC1, 0x09, 0x23, 0x33, 0x52, 0xF0,
+	0x15, 0x62, 0x72, 0xD1, 0x0A, 0x16, 0x24, 0x34, 0xE1, 0x25, 0xF1, 0x17,
+	0x18, 0x19, 0x1A, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x35, 0x36, 0x37, 0x38,
+	0x39, 0x3A, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4A, 0x53, 0x54,
+	0x55, 0x56, 0x57, 0x58, 0x59, 0x5A, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
+	0x69, 0x6A, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A, 0x82, 0x83,
+	0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8A, 0x92, 0x93, 0x94, 0x95, 0x96,
+	0x97, 0x98, 0x99, 0x9A, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7, 0xA8, 0xA9,
+	0xAA, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xC2, 0xC3,
+	0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6,
+	0xD7, 0xD8, 0xD9, 0xDA, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8, 0xE9,
+	0xEA, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7, 0xF8, 0xF9, 0xFA
+};
+EXPORT_SYMBOL_GPL(v4l2_jpeg_ref_table_chroma_ac_ht);
+
 /**
  * struct jpeg_stream - JPEG byte stream
  * @curr: current position in stream

include/media/v4l2-jpeg.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
···
 					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