diff options
Diffstat (limited to 'include/media/v4l2-jpeg.h')
| -rw-r--r-- | include/media/v4l2-jpeg.h | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/include/media/v4l2-jpeg.h b/include/media/v4l2-jpeg.h index ddba2a56c321..b65658a02e3c 100644 --- a/include/media/v4l2-jpeg.h +++ b/include/media/v4l2-jpeg.h @@ -14,6 +14,30 @@ #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 @@ -88,10 +112,30 @@ struct v4l2_jpeg_scan_header { }; /** + * 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 @@ -100,6 +144,7 @@ struct v4l2_jpeg_scan_header { * 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 @@ -119,6 +164,7 @@ struct v4l2_jpeg_header { 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); @@ -132,4 +178,12 @@ int v4l2_jpeg_parse_quantization_tables(void *buf, size_t len, u8 precision, 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 |