/*
* Support for Intel Camera Imaging ISP subsystem.
* Copyright (c) 2015, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*/
#include <linux/slab.h>
#include <math_support.h>
#include "sh_css_param_shading.h"
#include "ia_css_shading.h"
#include "assert_support.h"
#include "sh_css_defs.h"
#include "sh_css_internal.h"
#include "ia_css_debug.h"
#include "ia_css_pipe_binarydesc.h"
#include "sh_css_hrt.h"
#include "platform_support.h"
/* Bilinear interpolation on shading tables:
* For each target point T, we calculate the 4 surrounding source points:
* ul (upper left), ur (upper right), ll (lower left) and lr (lower right).
* We then calculate the distances from the T to the source points: x0, x1,
* y0 and y1.
* We then calculate the value of T:
* dx0*dy0*Slr + dx0*dy1*Sur + dx1*dy0*Sll + dx1*dy1*Sul.
* We choose a grid size of 1x1 which means:
* dx1 = 1-dx0
* dy1 = 1-dy0
*
* Sul dx0 dx1 Sur
* .<----->|<------------->.
* ^
* dy0|
* v T
* - .
* ^
* |
* dy1|
* v
* . .
* Sll Slr
*
* Padding:
* The area that the ISP operates on can include padding both on the left
* and the right. We need to padd the shading table such that the shading
* values end up on the correct pixel values. This means we must padd the
* shading table to match the ISP padding.
* We can have 5 cases:
* 1. All 4 points fall in the left padding.
* 2. The left 2 points fall in the left padding.
* 3. All 4 points fall in the cropped (target) region.
* 4. The right 2 points fall in the right padding.
* 5. All 4 points fall in the right padding.
* Cases 1 and 5 are easy to handle: we simply use the
* value 1 in the shading table.
* Cases 2 and 4 require interpolation that takes into
* account how far into the padding area the pixels
* fall. We extrapolate the shading table into the
* padded area and then interpolate.
*/
static void
crop_and_interpolate(unsigned int cropped_width,
unsigned int cropped_height,
unsigned int left_padding,
int right_padding,
int top_padding,
const struct ia_css_shading_table *in_table,
struct ia_css_shading_table *out_table,
enum ia_css_sc_color color)
{
unsigned int i, j,
sensor_width,
sensor_height,
table_width,
table_height,
table_cell_h,
out_cell_size,
in_cell_size,
out_start_row,
padded_width;
int out_start_col, /* can be negative to indicate padded space */
table_cell_w;
unsigned short *in_ptr,
*out_ptr;
assert(in_table != NULL);
assert(out_table != NULL);
sensor_width = in_table->sensor_width;
sensor_height = in_table->sensor_height;
table_width = in_table->width;
table_height = in_table->height;
in_ptr = in_table->data[color];
out_ptr = out_table->data[color];
padded_width = cropped_width + left_padding + right_padding;
out_cell_size = CEIL_DIV(padded_width, out_table->width - 1);
in_cell_size = CEIL_DIV(sensor_width, table_width - 1);
out_start_col = ((int)sensor_width - (int)cropped_width)/2 - left_padding;
out_start_row = ((int)sensor_height - (int)cropped_height)/2 - top_padding;
table_cell_w = (int)((table_width-1) * in_cell_size);
table_cell_h = (table_height-1) * in_cell_size;
for (i = 0; i < out_table->height; i++) {
int ty, src_y0, src_y1;
unsigned int sy0, sy1, dy0, dy1, divy;
/* calculate target point and make sure it falls within
the table */
ty = out_start_row + i * out_cell_size;
/* calculate closest source points in shading table and
make sure they fall within the table */
src_y0 = ty / (int)in_cell_size;
if (in_cell_size < out_cell_size)
src_y1 = (ty + out_cell_size) / in_cell_size;
else
src_y1 = src_y0 + 1;
src_y0 = clamp(src_y0, 0, (int)table_height-1);
src_y1 = clamp(src_y1, 0, (int)table_height-1);
ty = min(clamp(ty, 0, (int)sensor_height-1),
(int)table_cell_h);
/* calculate closest source points for distance computation */
sy0 = min(src_y0 * in_cell_size, sensor_height-1);
sy1 = min(src_y1 * in_cell_size, sensor_height-1);
/* calculate distance between source and target pixels */
dy0 = ty - sy0;
dy1 = sy1 - ty;
divy = sy1 - sy0;
if (divy == 0) {
dy0 = 1;
divy = 1;
}
for (j = 0; j < out_table->width; j++, out_ptr++) {
int tx, src_x0, src_x1;
unsigned int sx0, sx1, dx0, dx1, divx;
unsigned short s_ul, s_ur, s_ll, s_lr;
/* calculate target point */
tx = out_start_col + j * out_cell_size;
/* calculate closest source points. */
src_x0 = tx / (int)in_cell_size;
if (in_cell_size < out_cell_size) {
src_x1 = (tx + out_cell_size) /
(int)in_cell_size;
} else {
src_x1 = src_x0 + 1;
}
/* if src points fall in padding, select closest ones.*/
src_x0 = clamp(src_x0, 0, (int)table_width-1);
src_x1 = clamp(src_x1, 0, (int)table_width-1);
tx = min(clamp(tx, 0, (int)sensor_width-1),
(int)table_cell_w);
/* calculate closest source points for distance
computation */
sx0 = min(src_x0 * in_cell_size, sensor_width-1);
sx1 = min(src_x1 * in_cell_size, sensor_width-1);
/* calculate distances between source and target
pixels */
dx0 = tx - sx0;
dx1 = sx1 - tx;
divx = sx1 - sx0;
/* if we're at the edge, we just use the closest
point still in the grid. We make up for the divider
in this case by setting the distance to
out_cell_size, since it's actually 0. */
if (divx == 0) {
dx0 = 1;
divx = 1;
}
/* get source pixel values */
s_ul = in_ptr[(table_width*src_y0)+src_x0];
s_ur = in_ptr[(table_width*src_y0)+src_x1];
s_ll = in_ptr[(table_width*src_y1)+src_x0];
s_lr = in_ptr[(table_width*src_y1)+src_x1];
*out_ptr = (unsigned short) ((dx0*dy0*s_lr + dx0*dy1*s_ur + dx1*dy0*s_ll + dx1*dy1*s_ul) /
(divx*divy));
}
}
}
void
sh_css_params_shading_id_table_generate(
struct ia_css_shading_table **target_table,
#ifndef ISP2401
const struct ia_css_binary *binary)
#else
unsigned int table_width,
unsigned int table_height)
#endif
{
/* initialize table with ones, shift becomes zero */
#ifndef ISP2401
unsigned int i, j, table_width, table_height;
#else
unsigned int i, j;
#endif
struct ia_css_shading_table *result;
assert(target_table != NULL);
#ifndef ISP2401
assert(binary != NULL);
#endif
#ifndef ISP2401
table_width = binary->sctbl_width_per_color;
table_height = binary->sctbl_height;
#endif
result = ia_css_shading_table_alloc(table_width, table_height);
if (result == NULL) {
*target_table = NULL;
return;
}
for (i = 0; i < IA_CSS_SC_NUM_COLORS; i++) {
for (j = 0; j < table_height * table_width; j++)
result->data[i][j] = 1;
}
result->fraction_bits = 0;
*target_table = result;
}
void
prepare_shading_table(const struct ia_css_shading_table *in_table,
unsigned int sensor_binning,
struct ia_css_shading_table **target_table,
const struct ia_css_binary *binary,
unsigned int bds_factor)
{
unsigned int input_width,
input_height,
table_width,
table_height,
left_padding,
top_padding,
padded_width,
left_cropping,
i;
unsigned int bds_numerator, bds_denominator;
int right_padding;
struct ia_css_shading_table *result;
assert(target_table != NULL);
assert(binary != NULL);
if (!in_table) {
#ifndef ISP2401
sh_css_params_shading_id_table_generate(target_table, binary);
#else
sh_css_params_shading_id_table_generate(target_table,
binary->sctbl_legacy_width_per_color, binary->sctbl_legacy_height);
#endif
return;
}
padded_width = binary->in_frame_info.padded_width;
/* We use the ISP input resolution for the shading table because
shading correction is performed in the bayer domain (before bayer
down scaling). */
#if defined(USE_INPUT_SYSTEM_VERSION_2401)
padded_width = CEIL_MUL(binary->effective_in_frame_res.width + 2*ISP_VEC_NELEMS,
2*ISP_VEC_NELEMS);
#endif
input_height = binary->in_frame_info.res.height;
input_width = binary->in_frame_info.res.width;
left_padding = binary->left_padding;
left_cropping = (binary->info->sp.pipeline.left_cropping == 0) ?
binary->dvs_envelope.width : 2*ISP_VEC_NELEMS;
sh_css_bds_factor_get_numerator_denominator
(bds_factor, &bds_numerator, &bds_denominator);
left_padding = (left_padding + binary->info->sp.pipeline.left_cropping) * bds_numerator / bds_denominator - binary->info->sp.pipeline.left_cropping;
right_padding = (binary->internal_frame_info.res.width - binary->effective_in_frame_res.width * bds_denominator / bds_numerator - left_cropping) * bds_numerator / bds_denominator;
top_padding = binary->info->sp.pipeline.top_cropping * bds_numerator / bds_denominator - binary->info->sp.pipeline.top_cropping;
#if !defined(USE_WINDOWS_BINNING_FACTOR)
/* @deprecated{This part of the code will be replaced by the code
* in the #else section below to make the calculation same across
* all platforms.
* Android and Windows platforms interpret the binning_factor parameter
* differently. In Android, the binning factor is expressed in the form
* 2^N * 2^N, whereas in Windows platform, the binning factor is N*N}
*/
/* We take into account the binning done by the sensor. We do this
by cropping the non-binned part of the shading table and then
increasing the size of a grid cell with this same binning factor. */
input_width <<= sensor_binning;
input_height <<= sensor_binning;
/* We also scale the padding by the same binning factor. This will
make it much easier later on to calculate the padding of the
shading table. */
left_padding <<= sensor_binning;
right_padding <<= sensor_binning;
top_padding <<= sensor_binning;
#else
input_width *= sensor_binning;
input_height *= sensor_binning;
left_padding *= sensor_binning;
right_padding *= sensor_binning;
top_padding *= sensor_binning;
#endif /*USE_WINDOWS_BINNING_FACTOR*/
/* during simulation, the used resolution can exceed the sensor
resolution, so we clip it. */
input_width = min(input_width, in_table->sensor_width);
input_height = min(input_height, in_table->sensor_height);
#ifndef ISP2401
table_width = binary->sctbl_width_per_color;
table_height = binary->sctbl_height;
#else
/* This prepare_shading_table() function is called only in legacy API (not in new API).
Then, the legacy shading table width and height should be used. */
table_width = binary->sctbl_legacy_width_per_color;
table_height = binary->sctbl_legacy_height;
#endif
result = ia_css_shading_table_alloc(table_width, table_height);
if (result == NULL) {
*target_table = NULL;
return;
}
result->sensor_width = in_table->sensor_width;
result->sensor_height = in_table->sensor_height;
result->fraction_bits = in_table->fraction_bits;
/* now we crop the original shading table and then interpolate to the
requested resolution and decimation factor. */
for (i = 0; i < IA_CSS_SC_NUM_COLORS; i++) {
crop_and_interpolate(input_width, input_height,
left_padding, right_padding, top_padding,
in_table,
result, i);
}
*target_table = result;
}
struct ia_css_shading_table *
ia_css_shading_table_alloc(
unsigned int width,
unsigned int height)
{
unsigned int i;
struct ia_css_shading_table *me;
IA_CSS_ENTER("");
me = kmalloc(sizeof(*me), GFP_KERNEL);
if (!me)
return me;
me->width = width;
me->height = height;
me->sensor_width = 0;
me->sensor_height = 0;
me->fraction_bits = 0;
for (i = 0; i < IA_CSS_SC_NUM_COLORS; i++) {
me->data[i] =
sh_css_malloc(width * height * sizeof(*me->data[0]));
if (me->data[i] == NULL) {
unsigned int j;
for (j = 0; j < i; j++) {
sh_css_free(me->data[j]);
me->data[j] = NULL;
}
kfree(me);
return NULL;
}
}
IA_CSS_LEAVE("");
return me;
}
void
ia_css_shading_table_free(struct ia_css_shading_table *table)
{
unsigned int i;
if (table == NULL)
return;
/* We only output logging when the table is not NULL, otherwise
* logs will give the impression that a table was freed.
* */
IA_CSS_ENTER("");
for (i = 0; i < IA_CSS_SC_NUM_COLORS; i++) {
if (table->data[i]) {
sh_css_free(table->data[i]);
table->data[i] = NULL;
}
}
kfree(table);
IA_CSS_LEAVE("");
}
