How to use the camera._getLivePreview API for Ricoh Theta S

THETA API Usage
7

If you’re trying to get the stream into OpenCV,

POST request

string url = "Enter HTTP path of THETA here";
var request = HttpWebRequest.Create (url);
HttpWebResponse response = null;
request.Method = "POST";
request.Timeout = (int) (30 * 10000f); // to ensure  no timeout
request.ContentType = "application/json; charset = utf-8";

byte [] postBytes = Encoding.Default.GetBytes ( "Put the JSON data here");
request.ContentLength = postBytes.Length;

Get byte data

// The start of transmission of the post data
Stream reqStream = request.GetRequestStream ();
reqStream.Write (postBytes, 0, postBytes.Length) ;
reqStream.Close ();
stream = request.GetResponse () .GetResponseStream ();

BinaryReader reader = new BinaryReader (new BufferedStream (stream), new System.Text.ASCIIEncoding ());

Get the start and stop of the frames

...(http)
0xFF 0xD8      --|
[jpeg data]      |--1 frame of MotionJPEG
0xFF 0xD9      --|
...(http)
0xFF 0xD8      --|
[jpeg data]      |--1 frame of MotionJPEG
0xFF 0xD9      --|
...(http)

The starting 2 bytes are 0xFF, 0xD8 . The end bye is 0xD9

List<byte> imageBytes = new List<byte> ();
bool isLoadStart = false; // Binary flag taken at head of image
byte oldByte = 0; // Stores one previous byte of data
while( true ) {
    byte byteData = reader.ReadByte ();

if (!isLoadStart) {
    if (oldByte == 0xFF){
        // First binary image
       imageBytes.Add(0xFF);
    }
    if (byteData == 0xD8){
       // Second binary image
       imageBytes.Add(0xD8);

       // I took the head of the image up to the end binary
       isLoadStart = true;
    }
} else {
    // Put the image binaries into an array
    imageBytes.Add(byteData);

        // if the byte was the end byte
        // 0xFF -> 0xD9 case、end byte
        if(oldByte == 0xFF && byteData == 0xD9){
            // As this is the end byte
            // we'll generate the image from the data and can create the texture
            // imageBytes are used to reflect the texture
            // imageBytes are left empty
            // the loop returns the binary image head
            isLoadStart = false;
        }
    }
    oldByte = byteData;
}

import cv2
import urllib
import numpy as np

    stream=urllib.urlopen('http://localhost:8080/frame.mjpg')
    bytes=''
    while True:
        bytes+=stream.read(1024)
        a = bytes.find('\xff\xd8')
        b = bytes.find('\xff\xd9')
        if a!=-1 and b!=-1:
            jpg = bytes[a:b+2]
            bytes= bytes[b+2:]
            i = cv2.imdecode(np.fromstring(jpg, dtype=np.uint8),cv2.CV_LOAD_IMAGE_COLOR)
            cv2.imshow('i',i)
            if cv2.waitKey(1) ==27:
                exit(0)

This is from this outdated guide:

http://theta360developers.github.io/community-document/live-streaming.html#_untethered_wifi_streaming

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