Joseph Bradshaw
mbed serial interface for the OV528 camera (uCAM TTL 120 from 4D systems).
Dependents: mbed_uCAM_TTL120_20141118
Library for interfacing the mbed to the OV528 jpeg engine camera from Omnivision. I tested this program using the uCAM TTL 120 from 4D systems, now obsolete.
Above is a saved jpeg image from the camera at 480x640 resolution
Camera and TFT screen setup
Closeup of the TFT screen displaying a 60x80 pixel 16 bit color bitmap image. The RGB (565) pixel colors were reversed when read from the camera relative to the TFT screen so a bit mask and shift had to be applied when displaying the pixel color.
bit mask and shift
int k=12;
for(int i=0;i<60;i++){
for(int j=0;j<80;j++){
//returned 16-bit color is 565(RGB)
pixel_col = (imageData[k] << 8);
k++;
pixel_col += imageData[k];
k++;
// fputc(((picture[k] >> 8) & 0xff), fp); //write pixel high byte to file
// fputc(picture[k] & 0xff, fp); //write low byte
//swap R and B bits in returned pixel for TFT display
int TFT_pix_col = 0;
TFT_pix_col += (pixel_col & 0x001f) << 11;
TFT_pix_col += (pixel_col & 0xf800) >> 11;
TFT_pix_col += (pixel_col & 0x07e0);
TFT.pixel(j, i, TFT_pix_col); //Do something with the pixel
}
}
Revision 3:85db6ea8c0a4, committed 2014-11-26
- Comitter:
- jebradshaw
- Date:
- Wed Nov 26 16:57:13 2014 +0000
- Parent:
- 2:f80257456c6e
- Commit message:
- uCAM_TTL120 Library; -Improved cam_read() function with numbytes check and timeout
Changed in this revision
| uCAM_TTL120.cpp | Show annotated file Show diff for this revision Revisions of this file |
| uCAM_TTL120.h | Show annotated file Show diff for this revision Revisions of this file |
--- a/uCAM_TTL120.cpp Tue Nov 18 20:26:06 2014 +0000
+++ b/uCAM_TTL120.cpp Wed Nov 26 16:57:13 2014 +0000
@@ -12,24 +12,49 @@
timerCam->start();
}
-int uCAM_TTL120::uCAM_read(char *str, int numchars, float timeout){
- int i = 0;
- float t_start = timerCam->read();
+int uCAM_TTL120::uCAM_read(char *str, int numchars, float timeout){
+ Timer t_Frame;
+ int i=0;
+ int timeoutState=0;
+ t_Frame.start();
- while((timerCam->read() < (t_start + timeout)) && (i < numchars)){
- if(_cam.readable()){
- str[i] = _cam.getc();
- i++;
- }
- }
- if(timerCam->read() >= (t_start + timeout)){
- return -1;
- }
- if(i >= numchars){
- return -2;
- }
-
- return i;
+ while(timeoutState != 3 && (i < numchars)){
+ switch(timeoutState){
+ case 0:
+ while(_cam.readable()){ //if characters are in buffer, read them
+ str[i++] = _cam.getc();
+ if(i == numchars){
+ timeoutState = 3;
+ break;
+ }
+ }
+ //if no characters in buffer, initiate timeout
+ timeoutState = 1;
+ break;
+ case 1:
+ timeout = t_Frame.read() + timeout; //current time plus timeout time
+ timeoutState = 2;
+// pc.printf("Timeout initiated %f\r\n", timeout);
+ break;
+ case 2:
+ if(_cam.readable()){ //check buffer while timeout is running
+ str[i++] = _cam.getc();
+ if(i == numchars){
+ timeoutState = 3;
+ }
+ else{
+ timeoutState = 0;
+ }
+ break;
+ }
+ if(t_Frame.read() >= timeout) //if timeout has elapsed, exit the while loop with state 3
+ timeoutState = 3;
+ break;
+ default:
+ timeoutState = 0;
+ }//switch timeoutState
+ }//while timeoutState != 2
+ return i; //return number of bytes read
}
void uCAM_TTL120::uCAM_Command_Send(int command,char p1,char p2,char p3,char p4)
@@ -53,7 +78,7 @@
wait(.1);
//read serial buffer and wait for ACK (0xAA0E0DXX0000)
- uCAM_read(ser_read, 6, .1);
+ uCAM_read(ser_read, 6, .5);
if((ser_read[0] == 0xAA) &&
(ser_read[1] == 0x0E)){
if((command & 0xff) == ser_read[2])
@@ -82,7 +107,7 @@
wait(.2);
//read serial buffer and wait for ACK (0xAA0E0DXX0000)
- uCAM_read(ser_read, 6, .01);
+ uCAM_read(ser_read, 6, .1);
if((ser_read[0] == 0xAA) &&
(ser_read[1] == 0x0E) &&
@@ -103,7 +128,7 @@
uCAM_Command_Send(uCAM_ACK,0x0D,0x00,0x00,0x00);
printf("\r\n uCAM 120 Initialized\r\nDelaying 2 seconds for AGC and AEC \r\n circuits to stabilise before image capture.");
-/* wait(.5); //2 second delay before capturing first image
+ wait(.5); //2 second delay before capturing first image
printf(".");
wait(.5);
printf(".");
@@ -111,7 +136,7 @@
printf(".");
wait(.5);
printf(".\r\nFinished\r\n");
-*/
+
return 1; //Camera connection successful
}
}
@@ -129,14 +154,14 @@
int i;
uCAM_Command_Send(uCAM_INITIAL,0x00,0x06,0x01,0x00); // p2=0x06-16 bit color(RAW,565(RGB))
- // p3=0x01-80 x 60 bit resolution // p4=0x01-JPEG res 80 x 64
- wait(.02);
+ // p3=0x01-80 x 60 bit resolution
+ // p4=0x00-raw
for(i=0;i<7;i++) //clear the string
ser_read[i] = 0;
//read serial C buffer and wait for ACK (0xAA0E0DXX0000)
- uCAM_read(ser_read, 6, 100);
+ uCAM_read(ser_read, 6, .02); //.01
if((ser_read[0] == 0xAA) &&
(ser_read[1] == 0x0E) &&
@@ -166,7 +191,7 @@
(ser_read[1] == 0x0E) &&
(ser_read[2] == 0x01))
{
- wait(.050);
+ wait(.010);
return 1;
}
else
@@ -186,13 +211,13 @@
ser_read[i] = 0;
//read serial buffer and wait for ACK (0xAA0E0DXX0000)
- uCAM_read(ser_read, 6, 100);
+ uCAM_read(ser_read, 6, .100);
if((ser_read[0] == 0xAA) &&
(ser_read[1] == 0x0E) &&
(ser_read[2] == 0x01))
{
- wait(.05);
+ wait(.02);
return 1;
}
else
@@ -202,7 +227,7 @@
{
uCAM_Command_Send(uCAM_SNAPSHOT,0x01,0x00,0x00,0x00); // p1=0x01-Uncompressed Image
// p2 and p3 = 0, current frame
- wait(.05);
+ wait(.01);
if(uCAM_GetACK(uCAM_SNAPSHOT))
return 1;
@@ -210,17 +235,15 @@
return 0;
}
-int uCAM_TTL120::uCAM_send_GET_PICTURE_80x60_16COL_RAW(void)
+int uCAM_TTL120::uCAM_send_GET_PICTURE_80x60_16COL_RAW(FILE *fp)
{
char ser_read[7];
- char c;
unsigned long pic_bytes;
unsigned int i, j, k;
unsigned int serbytes_read;
- unsigned int pixel_col;
+ unsigned int pixel_col;
pic_bytes = 0;
- c=0;
serbytes_read = 0;
for(i=0;i<100;i++)
@@ -233,59 +256,46 @@
uCAM_Command_Send(uCAM_GET_PICTURE,0x01,0x00,0x00,0x00); // p1=0x01-Snapshot picture
wait(.3);
- //read serial C buffer and wait for ACK (0xAA0E0DXX0000)
- c=uCAM_read(ser_read, 6, 1);
- wait(.3);
+ if(uCAM_GetACK(uCAM_GET_PICTURE)) //returned get pic
+ {
+ //read serial C buffer and wait for ACK (0xAA0E0DXX0000)
+ char c=uCAM_read(ser_read, 6, .1);
- if(c==6) //received 6 bytes back
- {
- if((ser_read[0] == 0xAA) && //first 2 bytes indicate it was a DATA packet
- (ser_read[1] == 0x0E) &&
- (ser_read[2] == 0x04)) //returned get pic
- {
- //read serial C buffer and wait for ACK (0xAA0E0DXX0000)
- c=uCAM_read(ser_read, 6, 1);
+ if((ser_read[0] == 0xAA) && //first 2 bytes indicate it was a DATA packet
+ (ser_read[1] == 0x0A))
+ {
+ pic_bytes = (unsigned long)ser_read[3];
+ pic_bytes += (unsigned long)ser_read[4] << 8;
+ pic_bytes += (unsigned long)ser_read[5] << 16;
- if(c==6) //received 6 bytes back
- {
- if((ser_read[0] == 0xAA) && //first 2 bytes indicate it was a DATA packet
- (ser_read[1] == 0x0A))
- {
- pic_bytes = (unsigned long)ser_read[3];
- pic_bytes += (unsigned long)ser_read[4] << 8;
- pic_bytes += (unsigned long)ser_read[5] << 16;
-
- serbytes_read = uCAM_read(picture, pic_bytes, .200);
+ serbytes_read = uCAM_read(picture, pic_bytes, .200);
- if(serbytes_read == pic_bytes)
- {
- k=0;
- for(i=0;i<60;i++)
- {
- for(j=0;j<80;j++)
- {
- pixel_col = picture[k];
- k++;
-// printf("%d ", pixel_col);
-// uLCD144_Put_Pixel(j, i, pixel_col); //Do something with the pixel
- }
- }
+ if(serbytes_read == pic_bytes)
+ {
+ k=0;
+ for(i=0;i<60;i++)
+ {
+ for(j=0;j<80;j++)
+ {
+ pixel_col = picture[k];
+ k++;
+ fputc(((picture[k] >> 8) & 0xff), fp); //write pixel high byte to file
+ fputc(picture[k] & 0xff, fp); //write low byte
+// printf("%d ", pixel_col);
+// TFT.pixel(j, i, pixel_col); //Do something with the pixel
+ }
+ }
- uCAM_Command_Send(uCAM_ACK, 0x0A, 0x00, 0x01, 0x00);
+ uCAM_Command_Send(uCAM_ACK, 0x0A, 0x00, 0x01, 0x00);
- return pic_bytes;
- }
- else
- return -4;
- }
- else
- return -3;
- }
- }
- else
- return -2;
- }
- return -1;
+ return pic_bytes;
+ }
+ else
+ return -4;
+ }
+ }
+ else
+ return -1;
}
int uCAM_TTL120::uCAM_send_GET_PICTURE_80x60_2GRAY_RAW(void)
@@ -414,7 +424,7 @@
wait(.3);
//read serial C buffer and wait for ACK (0xAA0E0DXX0000)
- c=uCAM_read(ser_read, 6, 1);
+ c=uCAM_read(ser_read, 6, .1);
wait(.2);
if(c==6) //received 6 bytes back
@@ -424,7 +434,7 @@
(ser_read[2] == 0x04)) //returned get pic
{
//read serial C buffer and wait for ACK (0xAA0E0DXX0000)
- c=uCAM_read(ser_read, 6, 1);
+ c=uCAM_read(ser_read, 6, .1);
if(c==6) //received 6 bytes back
{
@@ -511,13 +521,13 @@
// _cam.baud(1228800);
}
-void uCAM_TTL120::uCAM_TakePic_RAW_16COLOR_80x60(void)
+void uCAM_TTL120::uCAM_TakePic_RAW_16COLOR_80x60(FILE *fp)
{
uCAM_send_INITIAL_80x60_16RAW();
wait(.1);
uCAM_send_SNAPSHOT();
wait(.1);
- uCAM_send_GET_PICTURE_80x60_16COL_RAW();
+ uCAM_send_GET_PICTURE_80x60_16COL_RAW(fp);
}
void uCAM_TTL120::uCAM_TakePic_RAW_2GRAY_80x60(void)
@@ -553,7 +563,7 @@
}
}
-int uCAM_TTL120::uCAM_get_jpeg(FILE *fileName){
+int uCAM_TTL120::uCAM_get_jpeg(FILE *fp){
char ser_read[7];
unsigned long pic_bytes;
@@ -651,11 +661,10 @@
if((verifyCode[0] & 0xff) == (vCodeCheck & 0xff)){
//pc.printf("\r\nPack ID = %d\r\n", packID);//debugging
- for(int j=0;j<imageDataSize;j++){
- fputc(imageData[j], fileName);
+ for(int j=0;j<imageDataSize;j++){ //write image data to file pointer
+ fputc(imageData[j], fp);
//pc.printf("%2X ", imageData[j]);
- }
-
+ }
packID++;
numPackages--;
}
--- a/uCAM_TTL120.h Tue Nov 18 20:26:06 2014 +0000
+++ b/uCAM_TTL120.h Wed Nov 26 16:57:13 2014 +0000
@@ -45,15 +45,15 @@
int uCAM_send_INITIAL_80x60_2RAW(void);
int uCAM_send_INITIAL_128x128_4RAW(void);
int uCAM_send_SNAPSHOT(void);
- int uCAM_send_GET_PICTURE_80x60_16COL_RAW(void);
+ int uCAM_send_GET_PICTURE_80x60_16COL_RAW(FILE *fp);
int uCAM_send_GET_PICTURE_80x60_2GRAY_RAW(void);
int uCAM_send_GET_PICTURE_128x128_4GRAY_RAW(void);
- void uCAM_TakePic_RAW_16COLOR_80x60(void);
+ void uCAM_TakePic_RAW_16COLOR_80x60(FILE *fp);
void uCAM_TakePic_RAW_2GRAY_80x60(void);
void uCAM_TakePic_RAW_4GRAY_128x128(void);
- int uCAM_get_jpeg(FILE *fileName);
+ int uCAM_get_jpeg(FILE *fp);
void uCAM_set_baud(void);