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Processing image in LPC1768 mbed microcontroller taken form LinkSprite JPEG Color Camera
I have bought LinkSprite JPEG Color Camera and a LPC1768 mbed microcontroller. By "LinkSprite" camera i can take image in jpeg formate and according to their provided tutorial i can transfer and see these image on desktop.But i want to process these image in "LPC1768 mbed" micro-controller.For example i want to loop through each row and column of that image to match a color. Can anyone tell me how can i receive the whole image into an 2D-array and then loop through the array to match with a color like red . Another problem when i transfer the image the data looks like. ff d8 ff e0 00 10 ...........40 c6 81 90 b9 aa ee 68 19 ff d9. I know that jpeg image starts with ff d9 and ends with ff d9. But how can i identify a pixel among those values and how can i compare a color whether it match with red color???
I have transferred image with these code:
#include "mbed.h"
#include "JPEGCamera.h"
DigitalOut myled1(LED1); //show successful picture was taken
DigitalOut myled2(LED2); //show end of sequence
DigitalOut myled3(LED3); //show picture take failed
DigitalOut myled4(LED4); //show camera is not ready
int main() {
JPEGCamera camera(p9, p10); // TX, RX
LocalFileSystem local("local"); //save images on mbed
Timer timer;
timer.start();
if(camera.setPictureSize(JPEGCamera::SIZE160x120))
{
myled1 = 1;
wait(2.0);
myled1 = 0;
wait(2.0);
}
for (int i = 1; i < 3; i++) {
if (camera.isReady()) {
char filename[32];
sprintf(filename, "/local/pict%03d.jpg", i);
printf("Picture: %s \n", filename);
if (camera.takePicture(filename)) {
while (camera.isProcessing()) {
camera.processPicture();
}
myled1 = 1; //show successful picture was taken
wait(2.0);
myled1 = 0;
} else {
printf("take picture failed\n");
myled3 = 1; //show picture take failed
wait(2.0);
myled3 = 0;
}
} else {
printf("camera is not ready\n");
myled4 = 1; //show camera is not ready
wait(2.0);
myled4 = 0;
}
}
myled2 = 1; //show end of sequence
wait(2.0);
myled2 = 0;
printf("time = %f\n", timer.read());
}
JPEGCamera.cpp
#include "JPEGCamera.h"
#define min(x, y) ((x) < (y)) ? (x) : (y)
const int RESPONSE_TIMEOUT = 500;
const int DATA_TIMEOUT = 1500;
Serial bt(p13, p14);
JPEGCamera::JPEGCamera(PinName tx, PinName rx) : Serial(tx, rx) {
baud(115200);
bt.baud(115200);
state = READY;
}
bool JPEGCamera::setPictureSize(JPEGCamera::PictureSize size, bool doReset) {
char buf[5] = {0x56, 0x00, 0x54, 0x01, (char) size};
int ret = sendReceive(buf, sizeof buf, 5);
if (ret == 5 && buf[0] == 0x76) {
if (doReset)
reset();
return true;
} else
return false;
}
bool JPEGCamera::isReady() {
return state == READY;
}
bool JPEGCamera::isProcessing() {
return state == PROCESSING;
}
bool JPEGCamera::takePicture(char *filename) {
if (state == READY) {
fp = fopen(filename, "wb");
if (fp != 0) {
if (takePicture()) {
imageSize = getImageSize();
address = 0;
state = PROCESSING;
} else {
fclose(fp);
printf("takePicture(%s) failed", filename);
state = ERROR;
}
} else {
printf("fopen() failed");
state = ERROR;
}
}
return state != ERROR;
}
bool JPEGCamera::processPicture() {
if (state == PROCESSING) {
bt.printf("\n\nNew Image \n\n");
if (address < imageSize) {
char data[2048];
int size = readData(data, min(sizeof(data), imageSize - address), address);
int ret = fwrite(data, size, 1, fp);
for (int i=0; i<size; i++) bt.printf("%x ",data[i]);
if (ret > 0)
address += size;
if (ret == 0 || address >= imageSize) {
stopPictures();
fclose(fp);
wait(0.1); // ????
state = ret > 0 ? READY : ERROR;
}
}
}
return state == PROCESSING || state == READY;
}
bool JPEGCamera::reset() {
char buf[4] = {0x56, 0x00, 0x26, 0x00};
int ret = sendReceive(buf, sizeof buf, 12);
if (ret == 12 && buf[0] == 0x0D) {
wait(4.0);
state = READY;
} else {
state = ERROR;
}
return state == READY;
}
bool JPEGCamera::takePicture() {
char buf[5] = {0x56, 0x00, 0x36, 0x01, 0x00};
int ret = sendReceive(buf, sizeof buf, 5);
return ret == 5 && buf[0] == 0x76;
}
bool JPEGCamera::stopPictures() {
char buf[5] = {0x56, 0x00, 0x36, 0x01, 0x03};
int ret = sendReceive(buf, sizeof buf, 5);
return ret == 4 && buf[0] == 0x76;
}
int JPEGCamera::getImageSize() {
char buf[9] = {0x56, 0x00, 0x34, 0x01, 0x00};
int ret = sendReceive(buf, sizeof buf, 9);
//The size is in the last 2 characters of the response.
return (ret == 9 && buf[0] == 0x76) ? (buf[7] << 8 | buf[8]) : 0;
}
int JPEGCamera::readData(char *dataBuf, int size, int address) {
char buf[16] = {0x56, 0x00, 0x32, 0x0C, 0x00, 0x0A, 0x00, 0x00,
address >> 8, address & 255, 0x00, 0x00, size >> 8, size & 255, 0x00, 0x0A
};
int ret = sendReceive(buf, sizeof buf, 5);
return (ret == 5 && buf[0] == 0x76) ? receive(dataBuf, size, DATA_TIMEOUT) : 0;
}
int JPEGCamera::sendReceive(char *buf, int sendSize, int receiveSize) {
while (readable()) getc();
for (int i = 0; i < sendSize; i++) putc(buf[i]);
return receive(buf, receiveSize, RESPONSE_TIMEOUT);
}
int JPEGCamera::receive(char *buf, int size, int timeout) {
timer.start();
timer.reset();
int i = 0;
while (i < size && timer.read_ms() < timeout) {
if (readable())
buf[i++] = getc();
}
return i;
}
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Is there anyone to help???
posted by imon bayazid 02 Sep 2014