Save frame from TangoService_connectOnFrameAvailable

Question

How can I save a frame via TangoService_connectOnFrameAvailable() and display it correctly on my computer? As this reference page mentions, the pixels are stored in the HAL_PIXE

Answer 1

I think that there is a better way to do if you can to do it offline. The best way to save the image should be something like this (don't forgot to create the folder Pictures or you won't save anything)

void onFrameAvailableRouter(void* context, TangoCameraId id, const TangoImageBuffer* buffer) {
  //To write the image in a txt file.
  std::stringstream name_stream;
  name_stream.setf(std::ios_base::fixed, std::ios_base::floatfield);
  name_stream.precision(3);
  name_stream << "/storage/emulated/0/Pictures/"
                <data,size * sizeof(uint8_t));
  f.close();
}

Then to convert the .txt file to png you can do this

inputFolder = "input"
outputFolderRGB = "output/rgb"
outputFolderGray = "output/gray"

input_filename  = "timestamp.txt"
output_filename = "rgb.png"
allFile = listdir(inputFolder)
numberOfFile = len(allFile)

if "input" in glob.glob("*"):
    if  "output/rgb" in glob.glob("output/*"):
        print ""
    else:
        makedirs("output/rgb")
        if "output/gray" in glob.glob("output/*"):
            print ""
        else:
            makedirs("output/gray")

    #The output reportories are ready
    for file in allFile:
        count+=1
        print "current file : ",count,"/",numberOfFile
        input_filename = file
        output_filename = input_filename[0:(len(input_filename)-3)]+"png"

        # load file into buffer
        data = np.fromfile(inputFolder+"/"+input_filename, dtype=np.uint8)  

        #To get RGB image  
        # create yuv image
        yuv = np.ndarray((height + height / 2, width), dtype=np.uint8, buffer=data)    
        # create a height x width x channels matrix with the datatype uint8 for rgb image
        img = np.zeros((height, width, channels), dtype=np.uint8);    
        # convert yuv image to rgb image
        cv2.cvtColor(yuv, cv2.COLOR_YUV2BGRA_NV21, img, channels)
        cv2.imwrite(outputFolderRGB+"/"+output_filename, img)

        #If u saved the image in graysacale use this part instead
        #yuvReal = np.ndarray((height, width), dtype=np.uint8, buffer=data)
        #cv2.imwrite(outputFolderGray+"/"+output_filename, yuvReal)
else:
    print "not any input"

You just have to put your .txt in a folder input It's a python script but if you prefer a c++ version it's very close.