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我正在寻找关于VideoFrame我试图转换为 opencv 的 openni 对象格式的一般描述/规范Mat。

是否有一些官方网站/文档可用？我在ros.org上找到了以下描述VideoFrameRefandOniFrame类的内容。但首先这似乎与 libfreenect 有关，其次我没有找到有关框架结构的任何具体信息（如尺寸、通道等）。

因此，任何链接或描述将不胜感激！

下面的代码是我正在试验的一个片段。内的转换部分while loop只产生一个黑色视频流。

import sys
import numpy as np
import cv2
from openni import openni2
from openni import _openni2 as c_api

openni2.initialize("./Redist")

device = openni2.Device.open_any()

ir_stream = device.create_ir_stream()
ir_stream.set_video_mode(c_api.OniVideoMode(pixelFormat = c_api.OniPixelFormat.ONI_PIXEL_FORMAT_GRAY16, resolutionX = 320, resolutionY = 240, fps = 30))
ir_stream.start()

while(True):
    frame = ir_stream.read_frame()
    frame_data = frame.get_buffer_as_uint16()
    img = np.frombuffer(frame_data, dtype=np.uint16)
    img.shape = (1, 240, 320)
    img = np.concatenate((img, img, img), axis=0)
    img = np.swapaxes(img, 0, 2)
    img = np.swapaxes(img, 0, 1)
    cv2.imshow("image", img)

    if cv2.waitKey(1) & 0xFF == ord('q'):
        cv2.destroyAllWindows()
        break

ir_stream.stop()
openni2.unload()
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1 回答 1

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我想回答我自己的问题，因为我确信其他人可以从这个工作示例中受益。

cv2.imshow()理解 uint8 (0..255)、uint32(0..2**32-1) 和 float (0..1) 所以我们必须使用img.astype(np.float) / 1024

import numpy as np
import cv2
from openni import openni2
from openni import _openni2 as c_api

openni2.initialize("./Redist")
device = openni2.Device.open_any()

ir_stream = device.create_ir_stream()
ir_stream.set_video_mode(c_api.OniVideoMode(pixelFormat = c_api.OniPixelFormat.ONI_PIXEL_FORMAT_GRAY16, resolutionX = 320, resolutionY = 240, fps = 30))
ir_stream.start()

while(True):
    frame = ir_stream.read_frame()

    # returns a 1-dim c_ushort_array of len: 76'800 = 320x240 each pixel having an uint16 value 0..65535
    frame_data = frame.get_buffer_as_uint16()

    # converting to numpy.ndarray which is still 1-dimension only
    img = np.frombuffer(frame_data, dtype=np.uint16)

    # convert to 3-dimensional array
    img.shape = (240, 320)

    # normalize values 
    img = img.astype(np.float) / 1024

    # Display image
    cv2.imshow("image", img)

    # Wait for input
    if cv2.waitKey(1) & 0xFF == ord('q'):
        cv2.destroyAllWindows()
        break

ir_stream.stop()
openni2.unload()

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于 2019-01-27T09:49:04.863 回答