如何 merge/feed 两个 uint8_t 缓冲区？

Question

嘿，很抱歉这个新手问题，但我想我只是遗漏了一些明显的东西……如果能得到一些指导，我会非常高兴：

esp_camera.h 的内联文档：

/**
 * @brief Data structure of camera frame buffer
 */
typedef struct {
    uint8_t * buf;              /*!< Pointer to the pixel data */
    size_t len;                 /*!< Length of the buffer in bytes */
    size_t width;               /*!< Width of the buffer in pixels */
    size_t height;              /*!< Height of the buffer in pixels */
    pixformat_t format;         /*!< Format of the pixel data */
} camera_fb_t;

加上演示代码摘录：来自 esp32 代码：

    //replace this with your own function
    display_image(fb->width, fb->height, fb->pixformat, fb->buf, fb->len);

获取帧缓冲区的代码

    camera_fb_t * fb = NULL;
    esp_err_t res = ESP_OK;

    fb = esp_camera_fb_get(); // framebuffer in grayscale

并将 fb 缓冲区送入 imagebuffer

    int w, h;
    int i, count;
    uint8_t *imagebuffer = quirc_begin(qr, &w, &h);

    //Feed 'fb' into 'imagebuffer' somehow?
    //-------------------------------
    // ----- DUMMY CODE?! not the proper way? ----
    imagebuffer = fb->buf; //fb's own buf field, holding the pixel data

    //Comment from quirc below:
    /* Fill out the image buffer here.
     * 'imagebuffer' is a pointer to a w*h bytes.
     * One byte per pixel, w pixels per line, h lines in the buffer.
     */
    //
    quirc_end(qr);

以下 quirc 的内嵌评论文档：

    /* These functions are used to process images for QR-code recognition.
     * quirc_begin() must first be called to obtain access to a buffer into
     * which the input image should be placed. Optionally, the current
     * width and height may be returned.
     *
     * After filling the buffer, quirc_end() should be called to process
     * the image for QR-code recognition. The locations and content of each
     * code may be obtained using accessor functions described below.
     */
    uint8_t *quirc_begin(struct quirc *q, int *w, int *h);
    void quirc_end(struct quirc *q);

https://github.com/dlbeer/quirc

我查看了代码、源文件等，但作为新手，我不知道如何将一个合并或输入另一个。

谁能给我指明正确的方向？浏览大量代码并不肮脏，但我对 C 的经验不足是这里的问题：S 谢谢！

Answer 1

图书馆的作者很友好地解释了它，在这里发布代码答案，因为它可能对其他人有帮助：

  int w, h;
  int i, count;
  uint8_t *buff = quirc_begin(qr, &w, &h);
  //
  int total_pixels = w * h;

  for (int i = 0; i < total_pixels; i++) {
    // grab a pixel from your source image at element i
    // convert it somehow, then store it
    buff[i] = fb->buf[i]; //?
  }
  //
  quirc_end(qr);

  count = quirc_count(qr);
  Serial.println("count found codes:");
  Serial.println(count);

github issue with lib author's explaination

如何 merge/feed 两个 uint8_t 缓冲区？

How to merge/feed two uint8_t buffers?

c

arduino

uint8t

esp32