How to get stream bytes and convert back to image - IOS

Question

How to get stream bytes and convert back to image, below is my code. But the images I get is blank. Why? Something wrong of the code?

I get the bytes from my NSOutputStream and convert back to NSData, then convert the NSData to image.

(void)stream:(NSStream *)theStream handleEvent:(NSStreamEvent)streamEvent {

switch (streamEvent) {

case NSStreamEventOpenCompleted:
    NSLog(@"Stream opened");
    break;
case NSStreamEventHasBytesAvailable:

    if (theStream == inputStream) {

        uint8_t buffer[5000]; 
        int len;

        while ([inputStream hasBytesAvailable]) {
            len = [inputStream read:buffer maxLength:sizeof(buffer)];
            NSLog(@"len=%d", len);
            if (len > 0) {

                NSData *pictureData = [NSData dataWithBytes:buffer length:len];

                UIImage *imagess = [[UIImage alloc]initWithData:pictureData];
                [imagesview setImage:imagess];




                                }

        }
    }
    break;

}

}

score 1 · Answer 1 · edited Nov 05 '14 at 15:05

This is a bit confusing in your use of NSOutPutStream. While you may be sending the image data with one (far end), you must be using a NSInputStream to receive it, no?

What you should be doing in 'NSStreamEventHasBytesAvailable:' is simply appending the data to a mutable data object. When you finally get 'NSStreamEventEndEncountered', that is when you would get your image:

{
  NSMutableData *data; // ivar
}

  // init it somewhere
  data = [NSMutableData new];

case NSStreamEventHasBytesAvailable:

if (theStream == inputStream) {

    uint8_t buffer[5000]; 
    int len;

    while ([inputStream hasBytesAvailable]) {
        len = [inputStream read:buffer maxLength:sizeof(buffer)];
        NSLog(@"len=%d", len);
        if (len > 0) {
            [data appendBytes:(const void *)buffer length:len];
        }
    }
}
break;

case NSStreamEventEndEncountered:
{
    if (theStream == inputStream) {
        UIImage *imagess = [[UIImage alloc]initWithData:data];
        [imagesview setImage:imagess];
    }
}   break;

How to get stream bytes and convert back to image - IOS

1 Answers1