FFmpeg/libavfilter/unsharp_kernel.h

/*
 * Copyright (C) 2013 Wei Gao <weigao@multicorewareinc.com>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef AVFILTER_UNSHARP_KERNEL_H
#define AVFILTER_UNSHARP_KERNEL_H

#include "libavutil/opencl.h"

const char *ff_kernel_unsharp_opencl = AV_OPENCL_KERNEL(
inline unsigned char clip_uint8(int a)
{
    if (a & (~0xFF))
        return (-a)>>31;
    else
        return a;
}

kernel void unsharp(global  unsigned char *src,
                    global  unsigned char *dst,
                    const global  unsigned int *mask_lu,
                    const global  unsigned int *mask_ch,
                    int amount_lu,
                    int amount_ch,
                    int step_x_lu,
                    int step_y_lu,
                    int step_x_ch,
                    int step_y_ch,
                    int scalebits_lu,
                    int scalebits_ch,
                    int halfscale_lu,
                    int halfscale_ch,
                    int src_stride_lu,
                    int src_stride_ch,
                    int dst_stride_lu,
                    int dst_stride_ch,
                    int height,
                    int width,
                    int ch,
                    int cw)
{
    global unsigned char *dst_y = dst;
    global unsigned char *dst_u = dst_y + height * dst_stride_lu;
    global unsigned char *dst_v = dst_u + ch * dst_stride_ch;

    global unsigned char *src_y = src;
    global unsigned char *src_u = src_y + height * src_stride_lu;
    global unsigned char *src_v = src_u + ch * src_stride_ch;

    global unsigned char *temp_dst;
    global unsigned char *temp_src;
    const global unsigned int *temp_mask;
    int global_id = get_global_id(0);
    int i, j, x, y, temp_src_stride, temp_dst_stride, temp_height, temp_width, temp_steps_x, temp_steps_y,
        temp_amount, temp_scalebits, temp_halfscale, sum, idx_x, idx_y, temp, res;
    if (global_id < width * height) {
        y = global_id / width;
        x = global_id % width;
        temp_dst = dst_y;
        temp_src = src_y;
        temp_src_stride = src_stride_lu;
        temp_dst_stride = dst_stride_lu;
        temp_height = height;
        temp_width = width;
        temp_steps_x = step_x_lu;
        temp_steps_y = step_y_lu;
        temp_mask = mask_lu;
        temp_amount = amount_lu;
        temp_scalebits = scalebits_lu;
        temp_halfscale = halfscale_lu;
    } else if ((global_id >= width * height) && (global_id < width * height + ch * cw)) {
        y = (global_id - width * height) / cw;
        x = (global_id - width * height) % cw;
        temp_dst = dst_u;
        temp_src = src_u;
        temp_src_stride = src_stride_ch;
        temp_dst_stride = dst_stride_ch;
        temp_height = ch;
        temp_width = cw;
        temp_steps_x = step_x_ch;
        temp_steps_y = step_y_ch;
        temp_mask = mask_ch;
        temp_amount = amount_ch;
        temp_scalebits = scalebits_ch;
        temp_halfscale = halfscale_ch;
    } else {
        y = (global_id - width * height - ch * cw) / cw;
        x = (global_id - width * height - ch * cw) % cw;
        temp_dst = dst_v;
        temp_src = src_v;
        temp_src_stride = src_stride_ch;
        temp_dst_stride = dst_stride_ch;
        temp_height = ch;
        temp_width = cw;
        temp_steps_x = step_x_ch;
        temp_steps_y = step_y_ch;
        temp_mask = mask_ch;
        temp_amount = amount_ch;
        temp_scalebits = scalebits_ch;
        temp_halfscale = halfscale_ch;
    }
    if (temp_amount) {
        sum = 0;
        for (j = 0; j <= 2 * temp_steps_y; j++) {
            idx_y = (y - temp_steps_y + j) <= 0 ? 0 : (y - temp_steps_y + j) >= temp_height ? temp_height-1 : y - temp_steps_y + j;
            for (i = 0; i <= 2 * temp_steps_x; i++) {
                idx_x = (x - temp_steps_x + i) <= 0 ? 0 : (x - temp_steps_x + i) >= temp_width ? temp_width-1 : x - temp_steps_x + i;
                sum += temp_mask[i + j * (2 * temp_steps_x + 1)] * temp_src[idx_x + idx_y * temp_src_stride];
            }
        }
        temp = (int)temp_src[x + y * temp_src_stride];
        res = temp + (((temp - (int)((sum + temp_halfscale) >> temp_scalebits)) * temp_amount) >> 16);
        temp_dst[x + y * temp_dst_stride] = clip_uint8(res);
    } else {
        temp_dst[x + y * temp_dst_stride] = temp_src[x + y * temp_src_stride];
    }
}

);

#endif /* AVFILTER_UNSHARP_KERNEL_H */