1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include <android/bitmap.h> 18 #include <jni.h> 19 20 #include <cmath> 21 #include <cstdlib> 22 23 #include "utils.h" 24 #include "_jni.h" 25 26 using android::apps::photoeditor::utils::LockBitmaps; 27 using android::apps::photoeditor::utils::UnlockBitmaps; 28 29 namespace { 30 31 uint32_t BilinearPixelInterpolation( 32 float x, float y, uint8_t *p00, uint8_t *p01, uint8_t *p10, uint8_t *p11) { 33 34 float coef4 = x * y; 35 float coef2 = x - coef4; // x * (1 - y) 36 float coef3 = y - coef4; // (1 - x) * y 37 float coef1 = 1 - x - coef3; // (1 - x) * (1 - y) 38 39 int dst_red = p00[0] * coef1 + p10[0] * coef2 + p01[0] * coef3 + p11[0] * coef4; 40 int dst_green = p00[1] * coef1 + p10[1] * coef2 + p01[1] * coef3 + p11[1] * coef4; 41 int dst_blue = p00[2] * coef1 + p10[2] * coef2 + p01[2] * coef3 + p11[2] * coef4; 42 if (dst_red > 255) { 43 dst_red = 255; 44 } 45 if (dst_green > 255) { 46 dst_green = 255; 47 } 48 if (dst_blue > 255) { 49 dst_blue = 255; 50 } 51 52 // alpha is not calculated, directly from any point should do. 53 return p00[3] << 24 | (dst_blue << 16) | (dst_green << 8) | dst_red; 54 } 55 56 void FisheyeMapPixels( 57 float px, float py, uint32_t x, uint32_t y, AndroidBitmapInfo *src_info, 58 AndroidBitmapInfo *dst_info, void *src_pixels, void *dst_pixels) { 59 if (x >= src_info->width || y >= src_info->height) { 60 return; 61 } 62 63 uint32_t px_floor = floor(px); 64 uint32_t py_floor = floor(py); 65 66 uint32_t *p00 = (uint32_t*)((char*)src_pixels + src_info->stride * py_floor) + px_floor; 67 uint32_t *p01, *p10, *p11; 68 if (py_floor + 1 < src_info->height) { 69 p01 = (uint32_t*)((char*)p00 + src_info->stride); 70 } else { 71 p01 = p00; 72 } 73 if (py_floor + 1 < src_info->width) { 74 p10 = p00 + 1; 75 p11 = p01 + 1; 76 } else { 77 p10 = p00; 78 p11 = p01; 79 } 80 81 uint32_t *dst = (uint32_t*)((char*)dst_pixels + dst_info->stride * y) + x; 82 *dst = BilinearPixelInterpolation(px - px_floor, py - py_floor, 83 (uint8_t*)p00, (uint8_t*)p01, (uint8_t*)p10, (uint8_t*)p11); 84 } 85 86 /* 87 * @param scale ranges from 0.0 to 1.0. 88 * @param focus_x is the X-coord of the center of the projection ranging from 0 to 1. 89 * @param focus_y is the Y-coord of the center of the projection ranging from 0 to 1. 90 */ 91 extern "C" JNIEXPORT void JNICALL Java_com_android_photoeditor_filters_ImageUtils_nativeFisheye( 92 JNIEnv *env, jobject obj, jobject src_bitmap, jobject dst_bitmap, 93 jfloat focus_x, jfloat focus_y, jfloat scale) { 94 pFisheyeType f = (pFisheyeType)JNIFunc[JNI_Fisheye].func_ptr; 95 return f(env, obj, src_bitmap, dst_bitmap, focus_x, focus_y, scale); 96 } 97 98 extern "C" void Fisheye( 99 JNIEnv *env, jobject obj, jobject src_bitmap, jobject dst_bitmap, 100 jfloat focus_x, jfloat focus_y, jfloat scale) { 101 AndroidBitmapInfo src_info; 102 AndroidBitmapInfo dst_info; 103 void* src_pixels; 104 void* dst_pixels; 105 106 int ret = LockBitmaps( 107 env, src_bitmap, dst_bitmap, &src_info, &dst_info, &src_pixels, &dst_pixels); 108 if (ret < 0) { 109 LOGE("LockBitmaps in FishEye failed, error=%d", ret); 110 return; 111 } 112 113 if (scale == 0) { 114 memcpy(dst_pixels, src_pixels, src_info.stride * src_info.height); 115 return; 116 } 117 118 float far_point = hypotf(src_info.height * focus_y, src_info.width * focus_x); 119 const float r = far_point * 1.15; // radius 120 const float r2 = r * r; 121 const uint32_t center_x = round(src_info.width * focus_x); 122 const uint32_t center_y = round(src_info.height * focus_y); 123 float alpha = 0.75 + scale * 2.0; 124 float linear_scale = far_point / 125 (M_PI_2 - atan(alpha * sqrtf(r2 - far_point * far_point) / far_point)); 126 127 for (uint32_t scan_line = 0; scan_line <= center_y; scan_line++) { 128 129 int y = scan_line - center_y; 130 int y2 = y * y; 131 132 for (uint32_t dst_x = 0; dst_x <= center_x; dst_x++) { 133 int x = dst_x - center_x; 134 float xy2 = (x * x + y2); 135 float s_xy2 = sqrtf(xy2); 136 float r_scale = linear_scale * (M_PI_2 - atan(alpha * sqrtf(r2 - xy2) / s_xy2)) / s_xy2; 137 float scaled_x = x * r_scale; 138 float scaled_y = y * r_scale; 139 int nx = center_x - x; 140 int ny = center_y - y; 141 float fpx = center_x + scaled_x; 142 float fnx = center_x - scaled_x; 143 float fpy = center_y + scaled_y; 144 float fny = center_y - scaled_y; 145 146 FisheyeMapPixels(fpx, fpy, dst_x, scan_line, &src_info, &dst_info, src_pixels, dst_pixels); 147 FisheyeMapPixels(fpx, fny, dst_x, ny, &src_info, &dst_info, src_pixels, dst_pixels); 148 FisheyeMapPixels(fnx, fpy, nx, scan_line, &src_info, &dst_info, src_pixels, dst_pixels); 149 FisheyeMapPixels(fnx, fny, nx, ny, &src_info, &dst_info, src_pixels, dst_pixels); 150 } 151 } 152 // Deal with the condition when x = 0 and y = 0 (dst_x = center_x and 153 // scan_line = center_y. 154 uint32_t *dst = (uint32_t*)((char*)dst_pixels + dst_info.stride * center_y) + center_x; 155 *dst = *((uint32_t*)((char*)src_pixels + src_info.stride * center_y) + center_x); 156 157 UnlockBitmaps(env, src_bitmap, dst_bitmap); 158 } 159 160 } // namespace 161
