Load sprite from a base64 string which came from a websocket - unity3d

Question

I am trying to turn a base64 String into an Sprite in Unity 3D, but my sprite in scene remains blank.
public var cardPicture : Image;
function ReceiveData(jsonReply : JSONObject) {
var pictureBytes : byte[] = System.Convert.FromBase64String(jsonReply.GetString("picture"));
var cardPictureTexture = new Texture2D( 720, 720);
Debug.Log(cardPictureTexture.LoadImage(pictureBytes));
var sprite : Sprite = new Sprite ();
sprite = Sprite.Create (cardPictureTexture, new Rect (0,0,720,720), new Vector2 (0.5f, 0.5f));
cardPicture.overrideSprite = sprite;
}
This prints out true, but I am not sure if it is loading the image appropriately from the bytes or if something else is going wrong. I am not sure what to check in order to determine what is going wrong either. Assigning some picture to the cardPicture in scene displays correctly.
I logged the jsonReply.picture and used an online base64 to image converter and it displayed the image correctly.

Answer 1

byte[] pictureBytes = System.Convert.FromBase64String(jsonReply.GetString("picture"));
Texture2D tex = new Texture2D(2, 2);
tex.LoadImage( imageBytes );
Sprite sprite = Sprite.Create(tex, new Rect(0.0f, 0.0f, tex.width, tex.height), new Vector2(0.5f, 0.5f), 100.0f);
cardPicture.overrideSprite = sprite;

Answer 2

I assume you are trying to fetch an image from a remote url and trying to parse bytes into a texture. In unity WWW has facilitated this and does not require user involvement in conversion.
I believe your response may have header details which might cause issues in converting to a texture. You may use a code like below,
public string Url = #"http://dummyimage.com/300/09f/fff.png";
void Start () {
// Starting a coroutine to avoid blocking
StartCoroutine ("LoadImage");
}
IEnumerator LoadImage()
{
WWW www = new WWW(Url);
yield return www;
Debug.Log ("Loaded");
Texture texture = www.texture;
this.gameObject.GetComponent<Renderer>().material.SetTexture( 0,texture );
}

Answer 3

I don't know if this is solved but i want to share my solution.
void Start()
{
StartCoroutine(GetQR());
}
IEnumerator GetQR()
{
using (UnityWebRequest www = UnityWebRequest.Get(GetQR_URL))
{
yield return www.SendWebRequest();
if (www.isNetworkError || www.isHttpError)
{
Debug.Log(www.error);
}
else
{
// Show results as text
Debug.Log(www.downloadHandler.text);
QRData qr = JsonUtility.FromJson<QRData>(www.downloadHandler.text);
string result = Regex.Replace(qr.img, #"^data:image\/[a-zA-Z]+;base64,", string.Empty);
CovertBase64ToImage(result);
}
}
}
void CovertBase64ToImage(string img)
{
byte[] bytes = Convert.FromBase64String(img);
Texture2D myTexture = new Texture2D(512,212);
myTexture.LoadImage(bytes);
Sprite sprite = Sprite.Create(myTexture, new Rect(0, 0, myTexture.width, myTexture.height), new Vector2(0.5f, 0.5f));
QRimage.transform.parent.gameObject.SetActive(true);
QRimage.sprite = sprite;
}
It is working perfectly on unity version 2019.4