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Diffstat (limited to 'jni/filters/edge.c')
| -rw-r--r-- | jni/filters/edge.c | 126 |
1 files changed, 0 insertions, 126 deletions
diff --git a/jni/filters/edge.c b/jni/filters/edge.c deleted file mode 100644 index 9f5d88f77..000000000 --- a/jni/filters/edge.c +++ /dev/null @@ -1,126 +0,0 @@ -/* - * Copyright (C) 2012 The Android Open Source Project - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - */ - -#include <math.h> -#include "filters.h" - -void JNIFUNCF(ImageFilterEdge, nativeApplyFilter, jobject bitmap, jint width, jint height, jfloat p) -{ - char* destination = 0; - AndroidBitmap_lockPixels(env, bitmap, (void**) &destination); - - // using contrast function: - // f(v) = exp(-alpha * v^beta) - // use beta ~ 1 - - float const alpha = 5.0f; - float const beta = p; - float const c_min = 100.0f; - float const c_max = 500.0f; - - // pixels must be 4 bytes - char * dst = destination; - - int j, k; - char * ptr = destination; - int row_stride = 4 * width; - - // set 2 row buffer (avoids bitmap copy) - int buf_len = 2 * row_stride; - char buf[buf_len]; - int buf_row_ring = 0; - - // set initial buffer to black - memset(buf, 0, buf_len * sizeof(char)); - for (j = 3; j < buf_len; j+=4) { - *(buf + j) = 255; // set initial alphas - } - - // apply sobel filter - for (j = 1; j < height - 1; j++) { - - for (k = 1; k < width - 1; k++){ - int loc = j * row_stride + k * 4; - - float bestx = 0.0f; - int l; - for (l = 0; l < 3; l++) { - float tmp = 0.0f; - tmp += *(ptr + (loc - row_stride + 4 + l)); - tmp += *(ptr + (loc + 4 + l)) * 2.0f; - tmp += *(ptr + (loc + row_stride + 4 + l)); - tmp -= *(ptr + (loc - row_stride - 4 + l)); - tmp -= *(ptr + (loc - 4 + l)) * 2.0f; - tmp -= *(ptr + (loc + row_stride - 4 + l)); - if (fabs(tmp) > fabs(bestx)) { - bestx = tmp; - } - } - - float besty = 0.0f; - for (l = 0; l < 3; l++) { - float tmp = 0.0f; - tmp -= *(ptr + (loc - row_stride - 4 + l)); - tmp -= *(ptr + (loc - row_stride + l)) * 2.0f; - tmp -= *(ptr + (loc - row_stride + 4 + l)); - tmp += *(ptr + (loc + row_stride - 4 + l)); - tmp += *(ptr + (loc + row_stride + l)) * 2.0f; - tmp += *(ptr + (loc + row_stride + 4 + l)); - if (fabs(tmp) > fabs(besty)) { - besty = tmp; - } - } - - // compute gradient magnitude - float mag = sqrt(bestx * bestx + besty * besty); - - // clamp - mag = MIN(MAX(c_min, mag), c_max); - - // scale to [0, 1] - mag = (mag - c_min) / (c_max - c_min); - - float ret = 1.0f - exp (- alpha * pow(mag, beta)); - ret = 255 * ret; - - int off = k * 4; - *(buf + buf_row_ring + off) = ret; - *(buf + buf_row_ring + off + 1) = ret; - *(buf + buf_row_ring + off + 2) = ret; - *(buf + buf_row_ring + off + 3) = *(ptr + loc + 3); - } - - buf_row_ring += row_stride; - buf_row_ring %= buf_len; - - if (j - 1 >= 0) { - memcpy((dst + row_stride * (j - 1)), (buf + buf_row_ring), row_stride * sizeof(char)); - } - - } - buf_row_ring += row_stride; - buf_row_ring %= buf_len; - int second_last_row = row_stride * (height - 2); - memcpy((dst + second_last_row), (buf + buf_row_ring), row_stride * sizeof(char)); - - // set last row to black - int last_row = row_stride * (height - 1); - memset((dst + last_row), 0, row_stride * sizeof(char)); - for (j = 3; j < row_stride; j+=4) { - *(dst + last_row + j) = 255; // set alphas - } - AndroidBitmap_unlockPixels(env, bitmap); -} |