display image sent over Bluetooth

RE: display image sent over Bluetooth

ovrebekk — Thu, 05 Sep 2019 06:50:52 GMT

What format do you save the file as in Photoshop?

Most likely the problem is with the conversion from an image to a C file. Are you using the program recommended by lydie below?

Best regards
Torbjørn

RE: display image sent over Bluetooth

yuval — Wed, 04 Sep 2019 13:16:27 GMT

thanks. a quick question. i want to save an image i create using Photoshop. but when i convert it and import it , the image is distorted and all i get on the LCD is unreadable. do you know what it the process from Photoshop all the way to the LCD (c file)?

RE: display image sent over Bluetooth

ovrebekk — Wed, 04 Sep 2019 07:04:05 GMT

Hi guys

I made an optimized driver a while back for the Adafruit capacitive touch display, which should also be based on the ILI9341 driver.

I replaced many of the single pixel updates with buffer updates to speed up the display operations.

The modified drivers can be found in the adafruit_touch_display folder in this repo:
https://github.com/NordicPlayground/nrf52-ble-multi-link-multi-role/tree/feature_tripple_phy_peripheral

Feel free to try it out, hopefully it will improve performance also in your application 🙂

Best regards
Torbjørn

RE: display image sent over Bluetooth

lydie — Tue, 03 Sep 2019 09:01:29 GMT

I have the same problem with the text. So when I want to display an image, I rotate the screen of 180, I display my image, and I rotate of 180 to return to the original position.

For the colors, my problem was with nrf_gfx_bmp565_draw. I changed this function by replacing the 2 loops for with:

 uint32_t cpt=0;

    for (int32_t i = 0; i < p_rect->height; i++)
    {
        for (uint32_t j = 0; j < p_rect->width; j++)
        {
            cpt++;
            idx = (uint32_t) (p_rect->height)*(p_rect->width)-cpt;
            pixel = img_buf[idx];
            pixel_draw(p_instance, p_rect->x + j, p_rect->y + i, pixel);
            
        }
    }

RE: display image sent over Bluetooth

yuval — Tue, 03 Sep 2019 08:49:55 GMT

the driver is ili9341, which is the same. when i modify the driver to display the image correct then now the text is reversed. wired. about the color - they are different , perhaps the driver is not config to 565

RE: display image sent over Bluetooth

lydie — Tue, 03 Sep 2019 08:10:56 GMT

It's also very slow for me, like 2 seconds to display an image, I don't know why, maybe it's because it displays pixel by pixel.

What is your driver? Because to remove the mirror effect, I modified some things in st7735.c.

Why your colors are incorrect? Colors are the opposite?

RE: display image sent over Bluetooth

yuval — Tue, 03 Sep 2019 06:32:55 GMT

thank you . it works. but 2 problems. its very slow , the image takes a few seconds to fully display.any idea how to make it faster?

the second , the image is displayed mirror and reverse. its like the image matrix values is reversed.is it because of the application? also the colors are incorrect

RE: display image sent over Bluetooth

ovrebekk — Mon, 02 Sep 2019 13:33:41 GMT

You should be able to check the data stored in the image_received by starting a debug session in SES, right clicking the image_received variable, and select Locate Memory.

To see the whole buffer you might need to change the Size parameter in the memory window.

Then you can put a breakpoint in the code at the point where you are about to use the data in image_received, and check if the data looks OK.

Best regards
Torbjørn

RE: display image sent over Bluetooth

lydie — Mon, 02 Sep 2019 05:58:57 GMT

I use ImageConverter565.

You can download it here:

https://github.com/mysensors/MySensorsArduinoExamples/blob/master/libraries/UTFT/Tools/ImageConverter565.exe

It generates a .c file

RE: display image sent over Bluetooth

yuval — Mon, 02 Sep 2019 05:51:33 GMT

i have a bmp image (320 x 240) and i want to transform it to C matrix array of 16bit (320 x 240).

how did you do that?

RE: display image sent over Bluetooth

lydie — Mon, 02 Sep 2019 01:23:18 GMT

Hi, sorry for my late answer and thanks for your reply.

Yes, I try to display image_received, but this array is changed when I receive data.

I don't know how can I check what is stored in image_received with the debugger. Do you have an idea?

RE: display image sent over Bluetooth

lydie — Mon, 02 Sep 2019 01:18:36 GMT

HI,

I still can't display an image sent over Bluetooth, but I can display an image shared in a RAM like this:

nrf_gfx_rect_t rect_step = NRF_GFX_RECT(26, 30,80 , 130);//nrf_gfx_width_get(p_lcd)
APP_ERROR_CHECK(nrf_gfx_rect_draw(p_lcd, &rect_step, 2, BLACK, false));
APP_ERROR_CHECK(nrf_gfx_bmp565_draw(p_lcd, &rect_step, step_img));

The image I want to display is step_img and its format is:

static const uint16_t step_img[]={
0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,   // 0x0010 (16)
0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0xFFDE, 0x6308,   // 0x0020 (32)
0x0000, 0x6310, 0xFFDE, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,   // 0x0030 (48)
0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,   // 0x0040 (64)
0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,   // 0x0050 (80)
0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,   // 0x0060 (96)
0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0xFFFF, 0x0000, 0x0000,   // 0x0070 (112)
0x0000, 0x0000, 0x2108, 0xFFFF,[...] }

RE: display image sent over Bluetooth

yuval — Sun, 01 Sep 2019 10:27:18 GMT

hi Iydie

can you share the code or explain how you used the nrf_gfx_bmp565_draw function. im trying to display an image on my LCD with than function without any success.

thanks

RE: display image sent over Bluetooth

ovrebekk — Wed, 07 Aug 2019 14:18:03 GMT

If I understand you correctly only the original 0xFFFF (white) data is displayed?

Have you used the debugger to check what is stored in the image_received buffer before the nrf_gfx_background_set command is run?

How do you declare the image_received buffer?

On a side note I would consider rewriting the loop function like this for clarity and efficiency:

for(int i = 2; i < 'length'; i += 4)
{
    red = array_data[i];
    green = array_data[i + 1];
    blue = array_data[i + 2];
    
    // Do processing
}

Best regards
Torbjørn