we're using a VC0706 camera along with a 8 GB Trascend SD card to take a snapshot and store it. You can find the library we're using here (GitHub - adafruit/Adafruit-VC0706-Serial-Camera-Library: Library for VC0706-based Serial JPEG Cameras). The problem is, when we run the example sketch "Snapshot" on our Arduino Mega, it takes up to 25 seconds to store a 48 K image. It seems too much time to us, so we're thinking maybe we're doing something wrong or maybe exists another way to store it faster.
#include <Adafruit_VC0706.h>
#include <SPI.h>
#include <SD.h>
#include <SoftwareSerial.h> // comment out this line if using Arduino V23 or earlier
#define chipSelect 4 // SD breakout board CS
SoftwareSerial cameraconnection = SoftwareSerial(69, 3); // On Mega: camera TX connected to pin 69 (A15), camera RX to pin 3:
Adafruit_VC0706 cam = Adafruit_VC0706(&cameraconnection);
void setup() {
// When using hardware SPI, the SS pin MUST be set to an
// output (even if not connected or used). If left as a
// floating input w/SPI on, this can cause lockuppage.
#if !defined(SOFTWARE_SPI)
#if defined(__AVR_ATmega1280__) || defined(__AVR_ATmega2560__)
if (chipSelect != 53) pinMode(53, OUTPUT); // SS on Mega
#else
if (chipSelect != 4) pinMode(4, OUTPUT); // SS on Uno, etc.
#endif
#endif
Serial.begin(9600);
Serial.println("VC0706 Camera snapshot test");
// see if the card is present and can be initialized:
if (!SD.begin(chipSelect)) {
Serial.println("Card failed, or not present");
// don't do anything more:
return;
}
// Try to locate the camera
if (cam.begin()) {
Serial.println("Camera Found:");
} else {
Serial.println("No camera found?");
return;
}
// Print out the camera version information (optional)
char *reply = cam.getVersion();
if (reply == 0) {
Serial.print("Failed to get version");
} else {
Serial.println("-----------------");
Serial.print(reply);
Serial.println("-----------------");
}
// Set the picture size - you can choose one of 640x480, 320x240 or 160x120
// Remember that bigger pictures take longer to transmit!
cam.setImageSize(VC0706_640x480); // biggest
//cam.setImageSize(VC0706_320x240); // medium
//cam.setImageSize(VC0706_160x120); // small
// You can read the size back from the camera (optional, but maybe useful?)
uint8_t imgsize = cam.getImageSize();
Serial.print("Image size: ");
if (imgsize == VC0706_640x480) Serial.println("640x480");
if (imgsize == VC0706_320x240) Serial.println("320x240");
if (imgsize == VC0706_160x120) Serial.println("160x120");
Serial.println("Snap in 3 secs...");
delay(3000);
if (! cam.takePicture())
Serial.println("Failed to snap!");
else
Serial.println("Picture taken!");
// Create an image with the name IMAGExx.JPG
char filename[13];
strcpy(filename, "IMAGE00.JPG");
for (int i = 0; i < 100; i++) {
filename[5] = '0' + i / 10;
filename[6] = '0' + i % 10;
// create if does not exist, do not open existing, write, sync after write
if (! SD.exists(filename)) {
break;
}
}
// Open the file for writing
File imgFile = SD.open(filename, FILE_WRITE);
// Get the size of the image (frame) taken
uint16_t jpglen = cam.frameLength();
Serial.print("Storing ");
Serial.print(jpglen, DEC);
Serial.print(" byte image.");
int32_t time = millis();
pinMode(8, OUTPUT);
// Read all the data up to # bytes!
byte wCount = 0; // For counting # of writes
while (jpglen > 0) {
// read 32 bytes at a time;
uint8_t *buffer;
uint8_t bytesToRead = min(32, jpglen); // change 32 to 64 for a speedup but may not work with all setups!
buffer = cam.readPicture(bytesToRead);
imgFile.write(buffer, bytesToRead);
if (++wCount >= 64) { // Every 2K, give a little feedback so it doesn't appear locked up
Serial.print('.');
wCount = 0;
}
//Serial.print("Read "); Serial.print(bytesToRead, DEC); Serial.println(" bytes");
jpglen -= bytesToRead;
}
imgFile.close();
time = millis() - time;
Serial.println("done!");
Serial.print(time); Serial.println(" ms elapsed");
}
void loop() {
}