Roi Resize

RoiResize算子功能为将输入图片按照ROI区域进行裁剪,然后将裁剪后的ROI区域等比例缩放到预定目标尺寸,最后对短边部分按照预置参数进行padding, 常用于对图片中的ROI区域提取并调整输出尺寸。算子支持双线性插值和最临近插值两种方式,不同的插值方式生成的图片结果也会有所差异。

算子效果

输入图像参数输出图像
imageROI = {100,200,399,359}
interpolation = HB_VP_INTER_LINEAR
paddingValue = {125,10,240}
image

原理

算子实现原理如下:

VP5roiResize1

其中,resize过程请参考 Resize 算子。

API接口

int32_t hbVPRoiResize(hbUCPTaskHandle_t *taskHandle, 
                      hbVPImage *dstImg, 
                      hbVPImage const *srcImg,
                      hbVPRoi const *roi,
                      hbVPRoiResizeParam const *roiResizeParam);

详细接口信息请查看 hbVPRoiResize

使用方法

// Include the header
#include "hobot/hb_ucp.h"
#include "hobot/vp/hb_vp.h"
#include "hobot/vp/hb_vp_roi_resize.h"

// init Image, allocate memory for image data
hbUCPSysMem src_mem;
hbUCPMallocCached(&src_mem, src_stride * src_height, 0);
hbVPImage src_img{HB_VP_IMAGE_FORMAT_Y,
                  HB_VP_IMAGE_TYPE_U8C1,
                  src_width,
                  src_height,
                  src_width,
                  src_mem.virAddr,
                  src_mem.phyAddr,
                  nullptr,
                  0,
                  0};

hbUCPSysMem dst_mem;
hbUCPMallocCached(&dst_mem, dst_stride * dst_height, 0);
hbVPImage dst_img{HB_VP_IMAGE_FORMAT_Y,
                  HB_VP_IMAGE_TYPE_U8C1,
                  dst_width,
                  dst_height,
                  dst_stride,
                  dst_mem.virAddr,
                  dst_mem.phyAddr,
                  nullptr,
                  0,
                  0};

// init roi
hbVPRoi roi;
roi.left = 100;
roi.top = 100;
roi.right = 399;
roi.bottom = 359;

// init param
hbVPRoiResizeParam param;
param.interpolation = HB_VP_INTER_LINEAR;
param.paddingValue[0] = 125;
param.paddingValue[1] = 10;
param.paddingValue[2] = 240;

// init task handle and schedule param
hbUCPTaskHandle_t task_handle{nullptr};
hbUCPSchedParam sched_param;
HB_UCP_INITIALIZE_SCHED_PARAM(&sched_param);
sched_param.backend = HB_UCP_DSP_CORE_0;

// create task
hbVPRoiResize(&task_handle, &dst_img, &src_img, &roi, &param);

// submit task
hbUCPSubmitTask(task_handle, &sched_param);

// wait for task done 
hbUCPWaitTaskDone(task_handle, 0);

// release task handle
hbUCPReleaseTask(task_handle);

// release memory
hbUCPFree(&src_mem);
hbUCPFree(&dst_mem);