gif-h 库的简单使用示例

Question

我正在尝试为 https://github.com/ginsweater/gif-h 创建一个最小使用示例

但是，从大小imageWidth*imageHeight的vector<uint8_t>开始，第二个 GifWriteFrame 调用会引发访问冲突读取位置异常

我的尝试：

#include <gif.h>
#include "BOBImageConversion.h"
int main(void)
{
    // USAGE:
    // Create a GifWriter struct. Pass it to GifBegin() to initialize and write the header.
    // Pass subsequent frames to GifWriteFrame().
    // Finally, call GifEnd() to close the file handle and free memory.
    int delay = 100;
    auto i1 = BOBImageIO::BOBLoadImage("Camera7.png");
    auto i2 = BOBImageIO::BOBLoadImage("Camera18.png");
    vector<uint8_t> vi1 = BOBImageConversion::ARGB2RGBAuint8(i1);
    vector<uint8_t> vi2 = BOBImageConversion::ARGB2RGBAuint8(i2);
    cout << (vi1.size() == i1.Width()*i1.Height()) << endl;         // true
    cout << (vi2.size() == i2.Width()*i2.Height()) << endl;         // true
    auto fileName = "gif.gif";
    GifWriter g;
    GifBegin(&g, fileName, i1.Width(), i1.Height(), delay);
    GifWriteFrame(&g, vi1.data(), i1.Width(), i1.Height(), delay);
    GifWriteFrame(&g, vi2.data(), i2.Width(), i2.Height(), delay); // Exception thrown: Access violation reading location 
    GifEnd(&g);
    return 0;
}

对于上述观点，发布的代码是一个最小示例。怎么了？

Answer 1

这有效

#include <vector>
#include <cstdint>
#include <gif.h>
int main()
{
    int width = 100;
    int height = 200;
    std::vector<uint8_t> vi1(width * height * 4, 0);
    std::vector<uint8_t> vi2(width * height * 4, 255);
    auto fileName = "bwgif.gif";
    int delay = 100;
    GifWriter g;
    GifBegin(&g, fileName, width, height, delay);
    GifWriteFrame(&g, vi1.data(), width, height, delay);
    GifWriteFrame(&g, vi2.data(), width, height, delay);
    GifEnd(&g);
    return 0;
}