Reading image and pulling, RGB and pixel number from GIF format image

Hello,

I am working on a code to pull the RGB values from a gif frame by frame, then load them into a file in a specific format to load into a LED lighting array. I cannot seem to get it to label the LED numbers correctly, or how I want them numbered. When running the following code through matlab it seems to label the LED numbers in a different order. Here is the code I am using.

sourceimage = '/Users/tapotter/anime/leda11.gif'; %Pull file to load
numframes = numel(imfinfo(sourceimage)); %Pull the number of frames
fid = fopen('FastLEDAnimation.txt', 'a+'); 
for frame = 1:numframes %Go through each frame of the gif
  fprintf('Frame:  %d Complete', frame); %Post to the console when each frame is complete
  [img, map] = imread(sourceimage, frame); % Open the image and create the map
  rgbimg = im2uint8(ind2rgb(img, map)); %turn the index into  unit8 rgb format
  crgb = reshape(permute(rgbimg, [3, 1, 2]), 3, []);  %makes a 3xnumpixels array
  framedelay = imfinfo(sourceimage); %Pulls the frame delay from imfinfo
  fdelay = framedelay.DelayTime; 
  pixcrgb = [1:size(crgb, 2); crgb];  %Sets up the readout to include what pixel its on(not working as I thought)
  fprintf(fid, 'leds[%d].setRGB(%d, %d, %d);\n', crgb);
  fprintf(fid, '\n FastLED.delay(%d)\n', fdelay);
end
fclose(fid);

Here is a sample of the output I am getting,

leds[0].setRGB(0, 0, 0);
leds[0].setRGB(0, 18, 20);
leds[20].setRGB(8, 8, 9);
leds[20].setRGB(34, 36, 20);
leds[34].setRGB(36, 20, 40);
leds[47].setRGB(33, 65, 70);
leds[22].setRGB(52, 54, 33);
leds[65].setRGB(70, 12, 70);
leds[80].setRGB(33, 65, 70);

It should be reading

    leds[0].setRGB(0, 0, 0);
    leds[1].setRGB(0, 18, 20);
    leds[2].setRGB(8, 8, 9);
    leds[3].setRGB(34, 36, 20);

When I look at the data that is generated for the "pixcrgb" data I can see it is correct, at least number going through the number of pixels in the image. I am attaching a screen shot of the data I am seeing through matlab. Does anyone know how I might get the required number from pixcrgb? Example at the top it is labeling the 1, 2, 3, 4, 5, followed by the RGB values. Next just to make sure I understand how the gif or image is being read, is it in this format?

//     0 >  1 >  2 >  3 >  4
//                         |
//     .----<----<----<----'
//     |
//     5 >  6 >  7 >  8 >  9
//                         |
//     .----<----<----<----'
//     |
//    10 > 11 > 12 > 13 > 14
//                         |
//     .----<----<----<----'
//     |
//    15 > 16 > 17 > 18 > 19

[Jan]

Perhaps the problem is only the line:

fid = fopen('FastLEDAnimation.txt', 'a+');

This appends the data to the end of the file. If there are some wrong data from an earlier creation, they are not overwritten.

[Travis Potter]

I delete the file after every run. If that was also the case it would still be in the correct order. I believe it has something to do with

pixcrgb = [1:size(crgb, 2); crgb];

This is the part that is outputting the LED number into the data string. I just need to select the right value. Right now it is setting the value as "size" I believe. I Just dont know what to change it to for it to put the 'counter' value instead.

Answer 1

[Jan]

Change

fprintf(fid, 'leds[%d].setRGB(%d, %d, %d);\n', crgb);

to:

fprintf(fid, 'leds[%d].setRGB(%d, %d, %d);\n', pixcrgb);

Otherwise pixcrgb = [1:size(crgb, 2); crgb]; is not considered anywhere.

[Travis Potter]

Ok that worked but it seems to stop at 255, it will keep going down the list but repeat 255. Here is an example once it reaches 255.

leds[238].setRGB(8, 8, 9);
leds[239].setRGB(18, 20, 20);
leds[240].setRGB(45, 136, 145);
leds[241].setRGB(0, 0, 0);
leds[242].setRGB(0, 0, 0);
leds[243].setRGB(0, 0, 0);
leds[244].setRGB(0, 0, 0);
leds[245].setRGB(76, 139, 144);
leds[246].setRGB(20, 40, 47);
leds[247].setRGB(8, 8, 9);
leds[248].setRGB(0, 0, 0);
leds[249].setRGB(0, 0, 0);
leds[250].setRGB(0, 0, 0);
leds[251].setRGB(0, 0, 0);
leds[252].setRGB(0, 0, 0);
leds[253].setRGB(0, 0, 0);
leds[254].setRGB(0, 0, 0);
leds[255].setRGB(0, 0, 0);
leds[255].setRGB(0, 0, 0);
leds[255].setRGB(0, 0, 0);
leds[255].setRGB(0, 0, 0);
leds[255].setRGB(0, 0, 0);
leds[255].setRGB(8, 8, 9);
leds[255].setRGB(20, 34, 36);
leds[255].setRGB(74, 152, 165);
leds[255].setRGB(0, 0, 0);
leds[255].setRGB(0, 0, 0);
leds[255].setRGB(0, 0, 0);
leds[255].setRGB(0, 0, 0);
leds[255].setRGB(114, 142, 140);
leds[255].setRGB(46, 100, 96);
leds[255].setRGB(8, 8, 9);

Is there a cap of a value for the '%d'?

Answer 2

[Travis Potter]

Example gif I am using is attached. Every gif has the same thing happen in the pixcrgb, once it gets to 255 it just repeats. Could it be reading a piece of data wrong, or skipping a value now causing it to skip ?