openmv什么时候可以使用VGA模式？

[18852865532]

我在把颜色识别和形状识别结合在一起的时候，发现可能是像素点太少的缘故，当距离较远或者角度不正的时候，会识别失败，所以想把QQVGA换成VGA,但是它会报错如下，有人知道怎么才能使用VGA模式吗？我用的7725v3和stm32H7芯片，所以不用担心处理速度的问题。

import sensor, image, time
color_threshold1 = (0, 255, 40, 80, 40, 70)
color_threshold2 = (0, 130, 40, 80, 40, 70)

sensor.reset() # Initialize the camera sensor.

sensor.set_pixformat(sensor.RGB565) # use RGB565.

sensor.set_framesize(sensor.QQVGA) # use QVGA for quailtiy ,use QQVGA for speed.

sensor.skip_frames(10) # Let new settings take affect.

sensor.set_auto_whitebal(False)

#关闭白平衡。白平衡是默认开启的，在颜色识别中，需要关闭白平衡。

clock = time.clock() # Tracks FPS.

#扩宽roi
def expand_roi(roi):

    # set for QQVGA 160*120

    extra = 5

    win_size = (160, 120)

    (x, y, width, height) = roi

    new_roi = [x-extra, y-extra, width+2*extra, height+2*extra]



    if new_roi[0] < 0:

        new_roi[0] = 0

    if new_roi[1] < 0:

        new_roi[1] = 0

    if new_roi[2] > win_size[0]:

        new_roi[2] = win_size[0]

    if new_roi[3] > win_size[1]:

        new_roi[3] = win_size[1]



    return tuple(new_roi)



while(True):

    clock.tick() # Track elapsed milliseconds between snapshots().

    img = sensor.snapshot() # Take a picture and return the image.

    #  pixels_threshold=100, area_threshold=100

    blobs = img.find_blobs([color_threshold1], area_threshold=150)



    if blobs:

    #如果找到了目标颜色

        print(blobs)

        for blob in blobs:

        #迭代找到的目标颜色区域

            is_rect = 0

            rect_s=0

            max_s = -1


            new_roi = expand_roi(blob.rect())


            for c in img.find_rects():

                is_rect = 1

                rect_s=c.y()*c.h()
                # img.draw_rectangle(x,y,w,h [,color[,thickness=1[,fill=False]]])

                if rect_s > max_s:

                    max_s = rect_s

                    max_rect = c

            if is_rect:

                # 如果有对应颜色的矩形 标记外框

                img.draw_rectangle(new_roi) # rect

                img.draw_rectangle(blob.rect()) # rect

                #用矩形标记出目标颜色区域

                img.draw_cross(blob[5], blob[6]) # cx, cy

                img.draw_rectangle(max_rect.x(), max_rect.y(), max_rect.w(),  max_rect.h(),color = (0, 255, 0))

                img.draw_rectangle(max_rect.x()-1, max_rect.y()-1, max_rect.w()+2,  max_rect.h()+2,color = (0, 255, 0))





    print(clock.fps()) # Note: Your OpenMV Cam runs about half as fast while

    # connected to your computer. The FPS should increase once disconnected.
![0_1563880779720_1.PNG](https://fcdn.singtown.com/55dd819e-826d-4e91-a4ac-083e8576c64b.PNG) 

[kidswong999]

VGA模式下是压缩图像，不能进行算法处理。

[18852865532]

@kidswong999 嗯，多谢解惑呀

[egxs]

能不能识别多种颜色然后同时画框

[kidswong999]

@egxs 不同的问题，单独发帖子。