Add support for Rec.709 encoding and inverse encoding.

Reported-by: Tim Harvey tharvey@gateworks.com Signed-off-by: Steve Longerbeam slongerbeam@gmail.com --- Changes in v7: - moved CSC tables to new module ipu-ic-csc.c. - express negative coefficients as true signed int's, for better readability. Changes in v5: - moved API changes to a previous patch. - moved CSC coeff calc to new function calc_csc_coeffs(). Changes in v4: - fix compile error. Chnges in v3: - none. Changes in v2: - only return "Unsupported YCbCr encoding" error if inf != outf, since if inf == outf, the identity matrix can be used. Reported by Tim Harvey. --- drivers/gpu/ipu-v3/ipu-ic-csc.c | 139 ++++++++++++++++++++++++++++++-- 1 file changed, 134 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/ipu-v3/ipu-ic-csc.c b/drivers/gpu/ipu-v3/ipu-ic-csc.c index 8e9150b1d668..09e94aa12c40 100644 --- a/drivers/gpu/ipu-v3/ipu-ic-csc.c +++ b/drivers/gpu/ipu-v3/ipu-ic-csc.c @@ -230,14 +230,133 @@ static const struct ipu_ic_csc_params *yuv2rgb_601[] = { &yuvl2rgbl_601, };

+/* + * REC.709 encoding from RGB full range to YUV full range: + * + * Y = .2126 * R + .7152 * G + .0722 * B + * U = -.1146 * R - .3854 * G + .5000 * B + 128 + * V = .5000 * R - .4542 * G - .0458 * B + 128 + */ +static const struct ipu_ic_csc_params rgbf2yuvf_709 = { + .coeff = { + { 54, 183, 19 }, + { -29, -99, 128 }, + { 128, -116, -12 }, + }, + .offset = { 0, 512, 512 }, + .scale = 1, +}; + +/* Rec.709 RGB full-range to YUV limited-range */ +static const struct ipu_ic_csc_params rgbf2yuvl_709 = { + .coeff = { + { 47, 157, 16, }, + { -26, -87, 112, }, + { 112, -102, -10, }, + }, + .offset = { 64, 512, 512, }, + .scale = 1, + .sat = true, +}; + +/* Rec.709 RGB limited-range to YUV full-range */ +static const struct ipu_ic_csc_params rgbl2yuvf_709 = { + .coeff = { + { 63, 213, 22, }, + { -34, -115, 149, }, + { 149, -135, -14, }, + }, + .offset = { -75, 512, 512, }, + .scale = 1, +}; + +/* Rec.709 RGB limited-range to YUV limited-range */ +static const struct ipu_ic_csc_params rgbl2yuvl_709 = { + .coeff = { + { 54, 183, 18, }, + { -30, -101, 131, }, + { 131, -119, -12, }, + }, + .offset = { 0, 512, 512, }, + .scale = 1, + .sat = true, +}; + +/* + * Inverse REC.709 encoding from YUV full range to RGB full range: + * + * R = 1. * Y + 0 * (Cb - 128) + 1.5748 * (Cr - 128) + * G = 1. * Y - .1873 * (Cb - 128) - .4681 * (Cr - 128) + * B = 1. * Y + 1.8556 * (Cb - 128) + 0 * (Cr - 128) + * + * equivalently (factoring out the offsets): + * + * R = 1. * Y + 0 * Cb + 1.5748 * Cr - 201.574 + * G = 1. * Y - .1873 * Cb - .4681 * Cr + 83.891 + * B = 1. * Y + 1.8556 * Cb + 0 * Cr - 237.517 + */ +static const struct ipu_ic_csc_params yuvf2rgbf_709 = { + .coeff = { + { 128, 0, 202 }, + { 128, -24, -60 }, + { 128, 238, 0 }, + }, + .offset = { -403, 168, -475 }, + .scale = 2, +}; + +/* Rec.709 YUV full-range to RGB limited-range */ +static const struct ipu_ic_csc_params yuvf2rgbl_709 = { + .coeff = { + { 110, 0, 173, }, + { 110, -21, -51, }, + { 110, 204, 0, }, + }, + .offset = { -314, 176, -376, }, + .scale = 2, +}; + +/* Rec.709 YUV limited-range to RGB full-range */ +static const struct ipu_ic_csc_params yuvl2rgbf_709 = { + .coeff = { + { 75, 0, 115, }, + { 75, -14, -34, }, + { 75, 135, 0, }, + }, + .offset = { -248, 77, -289, }, + .scale = 3, +}; + +/* Rec.709 YUV limited-range to RGB limited-range */ +static const struct ipu_ic_csc_params yuvl2rgbl_709 = { + .coeff = { + { 128, 0, 197, }, + { 128, -23, -59, }, + { 128, 232, 0, }, + }, + .offset = { -394, 164, -464, }, + .scale = 2, +}; + +static const struct ipu_ic_csc_params *rgb2yuv_709[] = { + &rgbf2yuvf_709, + &rgbf2yuvl_709, + &rgbl2yuvf_709, + &rgbl2yuvl_709, +}; + +static const struct ipu_ic_csc_params *yuv2rgb_709[] = { + &yuvf2rgbf_709, + &yuvf2rgbl_709, + &yuvl2rgbf_709, + &yuvl2rgbl_709, +}; + static int calc_csc_coeffs(struct ipu_ic_csc *csc) { const struct ipu_ic_csc_params **params_tbl; int tbl_idx;

- if (csc->out_cs.enc != V4L2_YCBCR_ENC_601) - return -ENOTSUPP; - tbl_idx = (QUANT_MAP(csc->in_cs.quant) << 1) | QUANT_MAP(csc->out_cs.quant);

@@ -250,8 +369,18 @@ static int calc_csc_coeffs(struct ipu_ic_csc *csc)

/* YUV <-> RGB encoding is required */

- params_tbl = (csc->in_cs.cs == IPUV3_COLORSPACE_YUV) ? - yuv2rgb_601 : rgb2yuv_601; + switch (csc->out_cs.enc) { + case V4L2_YCBCR_ENC_601: + params_tbl = (csc->in_cs.cs == IPUV3_COLORSPACE_YUV) ? + yuv2rgb_601 : rgb2yuv_601; + break; + case V4L2_YCBCR_ENC_709: + params_tbl = (csc->in_cs.cs == IPUV3_COLORSPACE_YUV) ? + yuv2rgb_709 : rgb2yuv_709; + break; + default: + return -ENOTSUPP; + }

csc->params = *params_tbl[tbl_idx];