[PATCH v8 3/5] gpu: ipu-v3: ipu-ic-csc: Add support for limited range encoding

Steve Longerbeam
2019-05-22T01:03:47Z

Add support for encodings to or from limited range quantization.

Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
---
Changes in v7:
- hard-code the coefficients instead of deriving the limited range
coefficients from the full2full coefficients on the fly with
fixed-point math.
- add support for RGB limited-range.
---
drivers/gpu/ipu-v3/ipu-ic-csc.c | 180 +++++++++++++++++++++++++++++---
1 file changed, 166 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/ipu-v3/ipu-ic-csc.c b/drivers/gpu/ipu-v3/ipu-ic-csc.c
index 5fb469cd64fe..8e9150b1d668 100644
--- a/drivers/gpu/ipu-v3/ipu-ic-csc.c
+++ b/drivers/gpu/ipu-v3/ipu-ic-csc.c
@@ -10,6 +10,10 @@
#include <linux/sizes.h>
#include "ipu-prv.h"

+#define QUANT_MAP(q) \
+ ((q) == V4L2_QUANTIZATION_FULL_RANGE || \
+ (q) == V4L2_QUANTIZATION_DEFAULT ? 0 : 1)
+
/* identity matrix */
static const struct ipu_ic_csc_params identity = {
.coeff = {
@@ -21,12 +25,87 @@ static const struct ipu_ic_csc_params identity = {
.scale = 2,
};

+/*
+ * RGB full-range to RGB limited-range
+ *
+ * R_lim = 0.8588 * R_full + 16
+ * G_lim = 0.8588 * G_full + 16
+ * B_lim = 0.8588 * B_full + 16
+ */
+static const struct ipu_ic_csc_params rgbf2rgbl = {
+ .coeff = {
+ { 220, 0, 0, },
+ { 0, 220, 0, },
+ { 0, 0, 220, },
+ },
+ .offset = { 64, 64, 64, },
+ .scale = 1,
+};
+
+/*
+ * RGB limited-range to RGB full-range
+ *
+ * R_full = 1.1644 * (R_lim - 16)
+ * G_full = 1.1644 * (G_lim - 16)
+ * B_full = 1.1644 * (B_lim - 16)
+ */
+static const struct ipu_ic_csc_params rgbl2rgbf = {
+ .coeff = {
+ { 149, 0, 0, },
+ { 0, 149, 0, },
+ { 0, 0, 149, },
+ },
+ .offset = { -37, -37, -37, },
+ .scale = 2,
+};
+
+/*
+ * YUV full-range to YUV limited-range
+ *
+ * Y_lim = 0.8588 * Y_full + 16
+ * Cb_lim = 0.8784 * (Cb_full - 128) + 128
+ * Cr_lim = 0.8784 * (Cr_full - 128) + 128
+ */
+static const struct ipu_ic_csc_params yuvf2yuvl = {
+ .coeff = {
+ { 220, 0, 0, },
+ { 0, 225, 0, },
+ { 0, 0, 225, },
+ },
+ .offset = { 64, 62, 62, },
+ .scale = 1,
+ .sat = true,
+};
+
+/*
+ * YUV limited-range to YUV full-range
+ *
+ * Y_full = 1.1644 * (Y_lim - 16)
+ * Cb_full = 1.1384 * (Cb_lim - 128) + 128
+ * Cr_full = 1.1384 * (Cr_lim - 128) + 128
+ */
+static const struct ipu_ic_csc_params yuvl2yuvf = {
+ .coeff = {
+ { 149, 0, 0, },
+ { 0, 146, 0, },
+ { 0, 0, 146, },
+ },
+ .offset = { -37, -35, -35, },
+ .scale = 2,
+};
+
static const struct ipu_ic_csc_params *rgb2rgb[] = {
&identity,
+ &rgbf2rgbl,
+ &rgbl2rgbf,
+ &identity,
};

static const struct ipu_ic_csc_params *yuv2yuv[] = {
&identity,
+ &yuvf2yuvl,
+ &yuvl2yuvf,
+ &identity,
};

/*
@@ -46,6 +125,41 @@ static const struct ipu_ic_csc_params rgbf2yuvf_601 = {
.scale = 1,
};

+/* BT.601 RGB full-range to YUV limited-range */
+static const struct ipu_ic_csc_params rgbf2yuvl_601 = {
+ .coeff = {
+ { 66, 129, 25, },
+ { -38, -74, 112, },
+ { 112, -94, -18, },
+ },
+ .offset = { 64, 512, 512, },
+ .scale = 1,
+ .sat = true,
+};
+
+/* BT.601 RGB limited-range to YUV full-range */
+static const struct ipu_ic_csc_params rgbl2yuvf_601 = {
+ .coeff = {
+ { 89, 175, 34, },
+ { -50, -99, 149, },
+ { 149, -125, -24, },
+ },
+ .offset = { -75, 512, 512, },
+ .scale = 1,
+};
+
+/* BT.601 RGB limited-range to YUV limited-range */
+static const struct ipu_ic_csc_params rgbl2yuvl_601 = {
+ .coeff = {
+ { 77, 150, 29, },
+ { -44, -87, 131, },
+ { 131, -110, -21, },
+ },
+ .offset = { 0, 512, 512, },
+ .scale = 1,
+ .sat = true,
+};
+
/*
* BT.601 YUV full-range to RGB full-range
*
@@ -69,39 +183,77 @@ static const struct ipu_ic_csc_params yuvf2rgbf_601 = {
.scale = 2,
};

+/* BT.601 YUV full-range to RGB limited-range */
+static const struct ipu_ic_csc_params yuvf2rgbl_601 = {
+ .coeff = {
+ { 110, 0, 154, },
+ { 110, -38, -78, },
+ { 110, 195, 0, },
+ },
+ .offset = { -276, 265, -358, },
+ .scale = 2,
+};
+
+/* BT.601 YUV limited-range to RGB full-range */
+static const struct ipu_ic_csc_params yuvl2rgbf_601 = {
+ .coeff = {
+ { 75, 0, 102, },
+ { 75, -25, -52, },
+ { 75, 129, 0, },
+ },
+ .offset = { -223, 136, -277, },
+ .scale = 3,
+};
+
+/* BT.601 YUV limited-range to RGB limited-range */
+static const struct ipu_ic_csc_params yuvl2rgbl_601 = {
+ .coeff = {
+ { 128, 0, 175, },
+ { 128, -43, -89, },
+ { 128, 222, 0, },
+ },
+ .offset = { -351, 265, -443, },
+ .scale = 2,
+};
+
static const struct ipu_ic_csc_params *rgb2yuv_601[] = {
&rgbf2yuvf_601,
+ &rgbf2yuvl_601,
+ &rgbl2yuvf_601,
+ &rgbl2yuvl_601,
};

static const struct ipu_ic_csc_params *yuv2rgb_601[] = {
&yuvf2rgbf_601,
+ &yuvf2rgbl_601,
+ &yuvl2rgbf_601,
+ &yuvl2rgbl_601,
};

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;

- if ((csc->in_cs.cs == IPUV3_COLORSPACE_YUV &&
- csc->in_cs.quant != V4L2_QUANTIZATION_FULL_RANGE) ||
- (csc->out_cs.cs == IPUV3_COLORSPACE_YUV &&
- csc->out_cs.quant != V4L2_QUANTIZATION_FULL_RANGE))
- return -ENOTSUPP;
-
- if ((csc->in_cs.cs == IPUV3_COLORSPACE_RGB &&
- csc->in_cs.quant != V4L2_QUANTIZATION_FULL_RANGE) ||
- (csc->out_cs.cs == IPUV3_COLORSPACE_RGB &&
- csc->out_cs.quant != V4L2_QUANTIZATION_FULL_RANGE))
- return -ENOTSUPP;
+ tbl_idx = (QUANT_MAP(csc->in_cs.quant) << 1) |
+ QUANT_MAP(csc->out_cs.quant);

if (csc->in_cs.cs == csc->out_cs.cs) {
csc->params = (csc->in_cs.cs == IPUV3_COLORSPACE_YUV) ?
- *yuv2yuv[0] : *rgb2rgb[0];
+ *yuv2yuv[tbl_idx] : *rgb2rgb[tbl_idx];
+
return 0;
}

- csc->params = (csc->in_cs.cs == IPUV3_COLORSPACE_YUV) ?
- *yuv2rgb_601[0] : *rgb2yuv_601[0];
+ /* YUV <-> RGB encoding is required */
+
+ params_tbl = (csc->in_cs.cs == IPUV3_COLORSPACE_YUV) ?
+ yuv2rgb_601 : rgb2yuv_601;
+
+ csc->params = *params_tbl[tbl_idx];

return 0;
}
--
2.17.1