Pyrealsense2: Colorizer not working / no implmentation of Align

idata — Tue, 03 Oct 2017 21:30:47 GMT

Hello All,

I'm having a bear of a time getting up and running with Pyrealsense2 python bindings as part of the Intel RealSense SDK v2.7.9 release (with the ultimate goal of using it with OpenCV 3.3's python bindings). I can't seem to find much actual documentation on use and almost no examples. Generally, because the bindings are advertised as Cython wrappers I assume that less some obvious syntactical differences any C++ example should work using the python wrappers. I've already run into three issues I can't figure out doing this and would be very grateful if anyone reading this can help me out a bit (or point me in the right direction)!

Colorize Doesn't Colorize:

Using the following snippet adapted from the simple example in the repo:

# First import the library

import numpy as np

import cv2

import pyrealsense2 as rs2

c = rs2.colorizer()

# Create a context object. This object owns the handles to all connected

# realsense devices

pipeline = rs2.pipeline()

pipeline.start()

while True:

# This call waits until a new coherent set of frames is available on a

# device. Calls to get_frame_data(...) and get_frame_timestamp(...) on a

# device will return stable values until wait_for_frames(...) is called.

frames = pipeline.wait_for_frames()

color = frames.get_color_frame()

depth = frames.get_depth_frame()

if (not depth) or (not color):

print("Color or Depth not available!")

break

depth_RGB = c.colorize(depth)

depth_img = np.asanyarray(depth_RGB.get_data())

# Show the image in a new window

cv2.namedWindow("Depth",cv2.WINDOW_NORMAL)

cv2.resizeWindow("Depth",640,480)

cv2.imshow("Depth",depth_img)

cv2.waitKey(0)

I get an image that looks something like below. It's limited to a reduced ROI in the full depth sensor field of view, "squashed" vertically, and certainly not re-colorized into 3 channel RGB of BGR.

Can't Discard Null Frame References:

In the same script I have the issue that the color frame stream always returns null frame references and the depth frame stream sometimes does as well. When this happens the statement `if (not depth) or (not color): break` is unsuccessful at preventing get_data from throwing an exception with `RuntimeError: null pointer passed for argument "frame_ref"`

No Implementation of Align:

A look at python.cpp seems to suggest that the python bindings do not implement the equivalent of rs2::context.create_align(RS2_STREAM_COLOR) as shown in the align C++ example. Is that the case, is this planned for future implementation?

I'm getting the sense it might be a better idea to work with librealsense exclusively in C++ to write a subroutine for frame grabbing, alignment transformation, and processing/clipping that called from a python environment with numpy and the OpenCV python bindings. Does that sound right?

Thanks again!

System ConfigurationCamera ModelSR300Firmware Version3.21.0.0Operating System VersionUbuntu 16.04 LTSKernel Version4.10.0-35-generic (UVC Patched)

Re: Pyrealsense2: Colorizer not working / no implmentation of Align

MartyG — Wed, 04 Oct 2017 07:09:19 GMT

I have very little knowledge of Python coding, so may not be of much help here. I did look at an SDK 2.0 script reference though, and noticed that it used the 'frameset' instruction instead of 'frames' for get_color_frame and get_depth_frame. So maybe you could try changing these lines to:

color = frameset.get_color_frame()

depth = frameset.get_depth_frame()

This is the page I referred to:

https://github.com/IntelRealSense/librealsense/tree/development/examples/align librealsense/examples/align at development · IntelRealSense/librealsense · GitHub

Re: Pyrealsense2: Colorizer not working / no implmentation of Align

idata — Tue, 10 Oct 2017 23:06:48 GMT

Hi Ryank,

Have you tried changing the lines MartyG suggested?

Regards,

-Yermi

topic Re: Pyrealsense2: Colorizer not working / no implmentation of Align in Items with no label

Pyrealsense2: Colorizer not working / no implmentation of Align

Re: Pyrealsense2: Colorizer not working / no implmentation of Align

Re: Pyrealsense2: Colorizer not working / no implmentation of Align