Camera display on (ILI9341) TFT screen almost working

Official Hardware Mega GIGA R1 WiFi
1

I am so close to getting this working but I cannot quite see how to fix this sorting algorithm.

image
image698×931 221 KB

As the attached picture shows, the image displayed is mirrored and the aspect ratio is wrong.

Here is the code.

#include "SPI.h"
#include "Adafruit_GFX.h"
#include "Adafruit_ILI9341.h"

#include "camera.h"
#include "ov767x.h"

// Using a OV7675 cam

OV7675 ov767x;

Camera cam(ov767x);

// This define colour mode CAMERA_RGB565 (otherwise use CAMERA_GRAYSCALE for greyscale)
#define IMAGE_MODE CAMERA_RGB565

// For the TFT Display using SPI interface
#define TFT_RST     8
#define TFT_DC      9
#define TFT_CS      10
#define TFT_MOSI    11
#define TFT_CLK     13

/*
  Other buffer instantiation options:
  FrameBuffer fb(0x30000000);
  FrameBuffer fb(320,240,2);
*/
FrameBuffer fb(320,240,2);        // this defines a buffer to handle colour images - width, height & bits per pixel (change last parameter to 1 for greyscale)

unsigned long lastUpdate = 0;


// Using a breakout, change pins as desired
Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC, TFT_MOSI, TFT_CLK, TFT_RST, 12);


void blinkLED(uint32_t count = 0xFFFFFFFF)
{
  pinMode(LED_BUILTIN, OUTPUT);
  while (count--) {
    digitalWrite(LED_BUILTIN, LOW);  // turn the LED on (HIGH is the voltage level)
    delay(50);                       // wait for a second
    digitalWrite(LED_BUILTIN, HIGH); // turn the LED off by making the voltage LOW
    delay(50);                       // wait for a second
  }
}


void setup() {
  // put your setup code here, to run once:

  Serial.begin(230400);
  while(!Serial) continue;
  Serial.println("Camera display on TFT demo!"); 
 
  tft.begin();
  
  // Init the cam QVGA, using 15fps instead of 30fps to get better refresh rate
  if (!cam.begin(CAMERA_R320x240, IMAGE_MODE, 15)) {
    blinkLED();
  }
  
  blinkLED(5);

  tft.fillScreen(ILI9341_BLACK);
  yield();
  tft.fillScreen(ILI9341_RED);
  yield();
  tft.fillScreen(ILI9341_GREEN);
  yield();
  tft.fillScreen(ILI9341_BLUE);
  yield();
  tft.fillScreen(ILI9341_BLACK);
  yield();


}

void loop() {

  lastUpdate = millis();
  
  // Grab frame and write to serial
  if (cam.grabFrame(fb, 3000) == 0) {
    static FrameBuffer outfb(0x30000000);
    for (int i = 0; i < 320; i++) {
      for (int j = 0; j < 240; j++) {
        ((uint16_t*)outfb.getBuffer())[j + i * 240] = ((uint16_t*)fb.getBuffer())[i + j * 320];
        uint8_t lo_hi[] = { (uint8_t)((uint16_t*)outfb.getBuffer())[j + i * 240], (uint8_t)(((uint16_t*)outfb.getBuffer())[j + i * 240] >> 8) };
        ((uint16_t*)outfb.getBuffer())[j + i * 240] = (lo_hi[0] << 8) + lo_hi[1];
      }
    }
    tft.drawRGBBitmap(0,0,(uint16_t*)outfb.getBuffer(), 240, 320);
    //delay(2000);
  } else {
    blinkLED(20);
  }

 }

If anyone can help, that'll be most appreciated.

Thanks.

2

Hello,
Not sure what you mean by aspect wrong, the pic you show is 500 pixels tall by 374 pixels wide which is .748 aspect. From what I can find on your camera it's a 0.3MP: OV7675 · active array size: 640×480. This is an aspect also of .75.
Your code is defining 320x240 which is likewise a .75 aspect.
As to the mirroring, in the void loop, your second for loop needs to be reversed I think count wise.
Not sure on code, but instead of 0 to 240, go 240 to 0.

for (int j = 240; j > 0; j++) {
3

You picked the right loop to fix the mirroring but your suggestion did not work. Instead I kept the for loop as is i.e. for (int j = 0; j < 240; j++) { ... }

and then changed this line:

((uint16_t*)outfb.getBuffer())[j + (i * 240)] = ((uint16_t*)fb.getBuffer())[239 - i + j * 320];

This fixed the mirror but unfortunately, this introduced a new error... I get a split screen.

image
image698×931 294 KB

Regarding the aspect ratio... you can see by the shape of the pushbutton... it's elongated (or squashed), so does not match actual shape.

I need to rotate the image but still fill the 240 x 320 screen correctly.

4

I solved the split screen issue as well. I should have subtracted 319 and not 239...

((uint16_t*)outfb.getBuffer())[j + (i * 240)] = ((uint16_t*)fb.getBuffer())[319 - i + j * 320];

Now I just have to fix the aspect ratio or use the correct rotation with correct screen fill.

5

Is it the TFT doing the reverting or the camera?

6

There is another example available in the Arduino IDE, called "CameraCaptureRawBytes". This works fine, so I'm assuming that it is TFT related as the camera code is the same.