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// Copyright 2015 Google Inc. All rights reserved.
//
// 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 "ios_image_load.h"
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <stdio.h>
#import <CoreImage/CoreImage.h>
#import <ImageIO/ImageIO.h>
std::vector<uint8_t> LoadImageFromFile(const char* file_name,
int* out_width, int* out_height,
int* out_channels) {
FILE* file_handle = fopen(file_name, "rb");
fseek(file_handle, 0, SEEK_END);
const size_t bytes_in_file = ftell(file_handle);
fseek(file_handle, 0, SEEK_SET);
std::vector<uint8_t> file_data(bytes_in_file);
fread(file_data.data(), 1, bytes_in_file, file_handle);
fclose(file_handle);
CFDataRef file_data_ref = CFDataCreateWithBytesNoCopy(NULL, file_data.data(),
bytes_in_file,
kCFAllocatorNull);
CGDataProviderRef image_provider =
CGDataProviderCreateWithCFData(file_data_ref);
const char* suffix = strrchr(file_name, '.');
if (!suffix || suffix == file_name) {
suffix = "";
}
CGImageRef image;
if (strcasecmp(suffix, ".png") == 0) {
image = CGImageCreateWithPNGDataProvider(image_provider, NULL, true,
kCGRenderingIntentDefault);
} else if ((strcasecmp(suffix, ".jpg") == 0) ||
(strcasecmp(suffix, ".jpeg") == 0)) {
image = CGImageCreateWithJPEGDataProvider(image_provider, NULL, true,
kCGRenderingIntentDefault);
} else {
CFRelease(image_provider);
CFRelease(file_data_ref);
fprintf(stderr, "Unknown suffix for file '%s'\n", file_name);
*out_width = 0;
*out_height = 0;
*out_channels = 0;
return std::vector<uint8_t>();
}
const int width = (int)CGImageGetWidth(image);
const int height = (int)CGImageGetHeight(image);
const int channels = 4;
CGColorSpaceRef color_space = CGColorSpaceCreateDeviceRGB();
const int bytes_per_row = (width * channels);
const int bytes_in_image = (bytes_per_row * height);
std::vector<uint8_t> result(bytes_in_image);
const int bits_per_component = 8;
CGContextRef context = CGBitmapContextCreate(result.data(), width, height,
bits_per_component, bytes_per_row, color_space,
kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);
CGColorSpaceRelease(color_space);
CGContextDrawImage(context, CGRectMake(0, 0, width, height), image);
CGContextRelease(context);
CFRelease(image);
CFRelease(image_provider);
CFRelease(file_data_ref);
*out_width = width;
*out_height = height;
*out_channels = channels;
return result;
}
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