From b8035f7988a82cbbabf1009b9f3234ff2431f8a4 Mon Sep 17 00:00:00 2001 From: Mirela Rabulea Date: Thu, 11 Mar 2021 01:28:49 +0100 Subject: media: Add parsing for APP14 data segment in jpeg helpers 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: 0 - CMYK for images that are encoded with four components - RGB for images that are encoded with three components 1 - An image encoded with three components using YCbCr colour encoding. 2 - An image encoded with four components using YCCK colour encoding. This is used in imx-jpeg decoder, to distinguish between YUV444 and RGB24. Signed-off-by: Mirela Rabulea Reviewed-by: Philipp Zabel Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- include/media/v4l2-jpeg.h | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'include/media') diff --git a/include/media/v4l2-jpeg.h b/include/media/v4l2-jpeg.h index 3a3344a97678..2dba843ce3bd 100644 --- a/include/media/v4l2-jpeg.h +++ b/include/media/v4l2-jpeg.h @@ -87,6 +87,24 @@ struct v4l2_jpeg_scan_header { /* 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 @@ -102,6 +120,7 @@ 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 @@ -121,6 +140,7 @@ 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); -- cgit v1.2.3-59-g8ed1b