software camera interface

ines · ‎2014-05-06

Posted on May 06, 2014 at 12:38

Hi all,

I'm working on the example using the

Omnivision camera ov2640, but I'm not sure about the

resolution of the image coming from the camera.

I would like to configure the camera with QQVGA resolution(160x120).

I have done this configuration :

const
unsigned 
char
OV2640_QQVGA[][2]=
{
{0xff, 0x00},
{0x2c, 0xff},
{0x2e, 0xdf},
{0xff, 0x01},
{0x3c, 0x32},
{0x11, 0x00},
{0x09, 0x02},
{0x04, 0xA8},
{0x13, 0xe5},
{0x14, 0x48},
{0x2c, 0x0c},
{0x33, 0x78},
{0x3a, 0x33},
{0x3b, 0xfB},
{0x3e, 0x00},
{0x43, 0x11},
{0x16, 0x10},
{0x4a, 0x81},
{0x21, 0x99},
{0x24, 0x40},
{0x25, 0x38},
{0x26, 0x82},
{0x5c, 0x00},
{0x63, 0x00},
{0x46, 0x3f},
{0x0c, 0x3c},
{0x61, 0x70},
{0x62, 0x80},
{0x7c, 0x05},
{0x20, 0x80},
{0x28, 0x30},
{0x6c, 0x00},
{0x6d, 0x80},
{0x6e, 0x00},
{0x70, 0x02},
{0x71, 0x94},
{0x73, 0xc1},
{0x3d, 0x34},
{0x5a, 0x57},
{0x12, 0x00},
//UXGA
{0x11, 0x00},
{0x17, 0x11},
{0x18, 0x75},
{0x19, 0x01},
{0x1a, 0x97},
{0x32, 0x36},
{0x03, 0x0f},
{0x37, 0x40},
{0x4f, 0xbb},
{0x50, 0x9c},
{0x5a, 0x57},
{0x6d, 0x80},
{0x6d, 0x38},
{0x39, 0x02},
{0x35, 0x88},
{0x22, 0x0a},
{0x37, 0x40},
{0x23, 0x00},
{0x34, 0xa0},
{0x36, 0x1a},
{0x06, 0x02},
{0x07, 0xc0},
{0x0d, 0xb7},
{0x0e, 0x01},
{0x4c, 0x00},
{0xff, 0x00},
{0xe5, 0x7f},
{0xf9, 0xc0},
{0x41, 0x24},
{0xe0, 0x14},
{0x76, 0xff},
{0x33, 0xa0},
{0x42, 0x20},
{0x43, 0x18},
{0x4c, 0x00},
{0x87, 0xd0},
{0x88, 0x3f},
{0xd7, 0x03},
{0xd9, 0x10},
{0xd3, 0x82},
{0xc8, 0x08},
{0xc9, 0x80},
{0x7d, 0x00},
{0x7c, 0x03},
{0x7d, 0x48},
{0x7c, 0x08},
{0x7d, 0x20},
{0x7d, 0x10},
{0x7d, 0x0e},
{0x90, 0x00},
{0x91, 0x0e},
{0x91, 0x1a},
{0x91, 0x31},
{0x91, 0x5a},
{0x91, 0x69},
{0x91, 0x75},
{0x91, 0x7e},
{0x91, 0x88},
{0x91, 0x8f},
{0x91, 0x96},
{0x91, 0xa3},
{0x91, 0xaf},
{0x91, 0xc4},
{0x91, 0xd7},
{0x91, 0xe8},
{0x91, 0x20},
{0x92, 0x00},
{0x93, 0x06},
{0x93, 0xe3},
{0x93, 0x02},
{0x93, 0x02},
{0x93, 0x00},
{0x93, 0x04},
{0x93, 0x00},
{0x93, 0x03},
{0x93, 0x00},
{0x93, 0x00},
{0x93, 0x00},
{0x93, 0x00},
{0x93, 0x00},
{0x93, 0x00},
{0x93, 0x00},
{0x96, 0x00},
{0x97, 0x08},
{0x97, 0x19},
{0x97, 0x02},
{0x97, 0x0c},
{0x97, 0x24},
{0x97, 0x30},
{0x97, 0x28},
{0x97, 0x26},
{0x97, 0x02},
{0x97, 0x98},
{0x97, 0x80},
{0x97, 0x00},
{0x97, 0x00},
{0xc3, 0xef},
{0xff, 0x00},
{0xba, 0xdc},
{0xbb, 0x08},
{0xb6, 0x24},
{0xb8, 0x33},
{0xb7, 0x20},
{0xb9, 0x30},
{0xb3, 0xb4},
{0xb4, 0xca},
{0xb5, 0x43},
{0xb0, 0x5c},
{0xb1, 0x4f},
{0xb2, 0x06},
{0xc7, 0x00},
{0xc6, 0x51},
{0xc5, 0x11},
{0xc4, 0x9c},
{0xbf, 0x00},
{0xbc, 0x64},
{0xa6, 0x00},
{0xa7, 0x1e},
{0xa7, 0x6b},
{0xa7, 0x47},
{0xa7, 0x33},
{0xa7, 0x00},
{0xa7, 0x23},
{0xa7, 0x2e},
{0xa7, 0x85},
{0xa7, 0x42},
{0xa7, 0x33},
{0xa7, 0x00},
{0xa7, 0x23},
{0xa7, 0x1b},
{0xa7, 0x74},
{0xa7, 0x42},
{0xa7, 0x33},
{0xa7, 0x00},
{0xa7, 0x23},
{0xc0, 0xc8},
{0xc1, 0x96},
{0x8c, 0x00},
{0x86, 0x3d},
{0x50, 0x92},
{0x51, 0x90},
{0x52, 0x2c},
{0x53, 0x00},
{0x54, 0x00},
{0x55, 0x88},
{0x5a, 0x50},
{0x5b, 0x3c},
{0x5c, 0x00},
{0xd3, 0x04},
{0x7f, 0x00},
{0xda, 0x00},
{0xe5, 0x1f},
{0xe1, 0x67},
{0xe0, 0x00},
{0xdd, 0x7f},
{0x05, 0x00},
{0xff, 0x00},
{0xe0, 0x04},
{0xc0, 0xc8},
{0xc1, 0x96},
{0x86, 0x3d},
{0x50, 0x92},
{0x51, 0x90},
{0x52, 0x2c},
{0x53, 0x00},
{0x54, 0x00},
{0x55, 0x88},
{0x57, 0x00},
{0x5a, 0x28},
{0x5b, 0x1E},
{0x5c, 0x00},
{0xd3, 0x08},
//was 0x08
{0xe0, 0x00},
{0xFF, 0x00},
{0x05, 0x00},
{0xDA, 0x08},
{0xda, 0x09},
{0x98, 0x00},
{0x99, 0x00},
{0x00, 0x00},*/
};

but this configuration doesn't work well .It gives me 113 lines instead of 120 lines .There is something wrong in the configuration !!

Has anyone solved this question!

below is the datasheet of tha camera omnivision 2640

de_koepi · ‎2014-05-06

Posted on May 06, 2014 at 14:55

I'm testing with the OV7670 which is quite similar in the SCCB/I2C interface. I get too little number of lines only when the PCLK is too fast and I read out the cam too slow.

What happens if you set the PCLK prescaler to return less fps?

ines · ‎2014-05-06

Posted on May 06, 2014 at 16:21

Thank you for your answer 🙂

this is the code to set pclk at 272khz(slow mode)

CAMERA_IO_Write(DeviceAddr, 0xff, 0x01); 
CAMERA_IO_Write(DeviceAddr, 0x11, 0x20);

the number of lines =114<120 lines

Added to that the period of pclk isn't constant:

Well,yellow color is for hsync signal,blue vsync and green for pclk signal .I wait for your support please 🙂

ines · ‎2014-05-07

Posted on May 07, 2014 at 17:02

Hi,this problem appears only when the resolution is QQVGA (160x120).Well for the resolution (320x240) the signals are right.Please i really need your help!!

stm322399 · ‎2014-05-07

Posted on May 07, 2014 at 17:51

I would be more confident in this measure when the scope capture shows both edges of the VSync signal.

Show us the capture that measures correctly the 240 lines in QVGA mode.