bmcv_image_yuv2hsv
==================

对YUV图像的指定区域转为HSV格式。


**处理器型号支持：**

该接口支持BM1684/BM1684X。


**接口形式：**

    .. code-block:: c

         bm_status_t bmcv_image_yuv2hsv(
                 bm_handle_t handle,
                 bmcv_rect_t rect,
                 bm_image    input,
                 bm_image    output);


**参数说明：**

* bm_handle_t handle

  输入参数。 bm_handle 句柄。

* bmcv_rect_t rect

  描述了原图中待转换区域的起始坐标以及大小。具体参数可参见bmcv_image_crop接口中的描述。

* bm_image input

  输入参数。输入图像的 bm_image，bm_image 需要外部调用 bmcv_image_create 创建。image 内存可以使用 bm_image_alloc_dev_mem 或者 bm_image_copy_host_to_device 来开辟新的内存，或者使用 bmcv_image_attach 来 attach 已有的内存。

* bm_image output

  输出参数。输出 bm_image，bm_image 需要外部调用 bmcv_image_create 创建。image 内存可以通过 bm_image_alloc_dev_mem 来开辟新的内存，或者使用 bmcv_image_attach 来 attach 已有的内存。如果不主动分配将在 api 内部进行自行分配。


**返回值说明：**

* BM_SUCCESS: 成功

* 其他:失败


**格式支持：**

bm1684： 该接口目前支持以下 image_format:

+-----+------------------------+------------------------+
| num | input image_format     | output image_format    |
+=====+========================+========================+
|  1  | FORMAT_YUV420P         | FORMAT_HSV_PLANAR      |
+-----+------------------------+------------------------+
|  2  | FORMAT_NV12            | FORMAT_HSV_PLANAR      |
+-----+------------------------+------------------------+
|  3  | FORMAT_NV21            | FORMAT_HSV_PLANAR      |
+-----+------------------------+------------------------+

bm1684x： 该接口目前

- 支持以下输入色彩格式:

+-----+-------------------------------+
| num | input image_format            |
+=====+===============================+
|  1  | FORMAT_YUV420P                |
+-----+-------------------------------+
|  2  | FORMAT_NV12                   |
+-----+-------------------------------+
|  3  | FORMAT_NV21                   |
+-----+-------------------------------+

- 支持输出色彩格式:

+-----+-------------------------------+
| num | output image_format           |
+=====+===============================+
|  1  | FORMAT_HSV180_PACKED          |
+-----+-------------------------------+
|  2  | FORMAT_HSV256_PACKED          |
+-----+-------------------------------+

目前支持以下 data_type:

+-----+--------------------------------+
| num | data_type                      |
+=====+================================+
|  1  | DATA_TYPE_EXT_1N_BYTE          |
+-----+--------------------------------+


**注意事项：**

1、在调用该接口之前必须确保输入的 image 内存已经申请。



**代码示例：**

    .. code-block:: c


        int channel   = 2;
        int width     = 1920;
        int height    = 1080;
        int dev_id    = 0;
        bm_handle_t handle;
        bm_status_t dev_ret = bm_dev_request(&handle, dev_id);
        std::shared_ptr<unsigned char> src_ptr(
                new unsigned char[channel * width * height],
                std::default_delete<unsigned char[]>());
        std::shared_ptr<unsigned char> res_ptr(
                new unsigned char[channel * width * height],
                std::default_delete<unsigned char[]>());
        unsigned char * src_data = src_ptr.get();
        unsigned char * res_data = res_ptr.get();
        for (int i = 0; i < channel * width * height; i++) {
            src_data[i] = rand() % 255;
        }
        // calculate res
        bmcv_rect_t rect;
        rect.start_x   = 0;
        rect.start_y   = 0;
        rect.crop_w    = width;
        rect.crop_h    = height;
        bm_image input, output;
        bm_image_create(handle,
                        height,
                        width,
                        FORMAT_NV12,
                        DATA_TYPE_EXT_1N_BYTE,
                        &input);
        bm_image_alloc_dev_mem(input);
        bm_image_copy_host_to_device(input, (void **)&src_data);
        bm_image_create(handle,
                        height,
                        width,
                        FORMAT_HSV_PLANAR,
                        DATA_TYPE_EXT_1N_BYTE,
                        &output);
        bm_image_alloc_dev_mem(output);
        if (BM_SUCCESS != bmcv_image_yuv2hsv(handle, rect, input, output)) {
            std::cout << "bmcv yuv2hsv error !!!" << std::endl;
            bm_image_destroy(input);
            bm_image_destroy(output);
            bm_dev_free(handle);
            exit(-1);
        }
        bm_image_copy_device_to_host(output, (void **)&res_data);
        bm_image_destroy(input);
        bm_image_destroy(output);
        bm_dev_free(handle);