I have a ESP32-S3-WROOM module by Freenove which has camera and micro SD card module. I can take a snapshot a PIXELFORMAT_JPEG photo. However, when I change the pixelformat with "PIXELFORMAT_GRAYSCALE",the module is capturing the raw data(1 byte for each pixel) which is 480kB constant for SVGA(600x800).
How can I compress this raw data to jpg? I also tried the way of saving the photo to ".jpg" file. However it did not worked.
Also this is my capturing code for it:
/**********************************************************************
Filename : Camera and SDcard
Description : Use the onboard buttons to take photo and save them to an SD card.
Auther : www.freenove.com
Modification: 2022/11/02
**********************************************************************/
#include "esp_camera.h"
#define CAMERA_MODEL_ESP32S3_EYE
#include "camera_pins.h"
#include "ws2812.h"
#include "sd_read_write.h"
#define BUTTON_PIN 0
void setup() {
Serial.begin(500000);
Serial.setDebugOutput(false);
Serial.println();
pinMode(BUTTON_PIN, INPUT_PULLUP);
ws2812Init();
sdmmcInit();
//removeDir(SD_MMC, "/camera");
createDir(SD_MMC, "/camera");
listDir(SD_MMC, "/camera", 0);
if(cameraSetup()==1){
ws2812SetColor(2);
}
else{
ws2812SetColor(1);
return;
}
}
void loop() {
if(digitalRead(BUTTON_PIN)==LOW){
delay(20);
if(digitalRead(BUTTON_PIN)==LOW){
ws2812SetColor(3);
while(digitalRead(BUTTON_PIN)==LOW);
camera_fb_t * fb = NULL;
fb = esp_camera_fb_get();
if (fb != NULL) {
int photo_index = readFileNum(SD_MMC, "/camera");
if(photo_index!=-1)
{
String path = "/camera/" + String(photo_index) +".jpg";
Serial.println(fb->len);
writejpg(SD_MMC, path.c_str(), fb->buf, fb->len);
}
esp_camera_fb_return(fb);
}
else {
Serial.println("Camera capture failed.");
}
ws2812SetColor(2);
}
}
}
int cameraSetup(void) {
camera_config_t config;
config.ledc_channel = LEDC_CHANNEL_0;
config.ledc_timer = LEDC_TIMER_0;
config.pin_d0 = Y2_GPIO_NUM;
config.pin_d1 = Y3_GPIO_NUM;
config.pin_d2 = Y4_GPIO_NUM;
config.pin_d3 = Y5_GPIO_NUM;
config.pin_d4 = Y6_GPIO_NUM;
config.pin_d5 = Y7_GPIO_NUM;
config.pin_d6 = Y8_GPIO_NUM;
config.pin_d7 = Y9_GPIO_NUM;
config.pin_xclk = XCLK_GPIO_NUM;
config.pin_pclk = PCLK_GPIO_NUM;
config.pin_vsync = VSYNC_GPIO_NUM;
config.pin_href = HREF_GPIO_NUM;
config.pin_sscb_sda = SIOD_GPIO_NUM;
config.pin_sscb_scl = SIOC_GPIO_NUM;
config.pin_pwdn = PWDN_GPIO_NUM;
config.pin_reset = RESET_GPIO_NUM;
config.xclk_freq_hz = 20000000;
config.frame_size = FRAMESIZE_SVGA;
config.pixel_format = PIXFORMAT_GRAYSCALE; // for streaming
config.grab_mode = CAMERA_GRAB_WHEN_EMPTY;
config.fb_location = CAMERA_FB_IN_PSRAM;
config.jpeg_quality = 20;
config.fb_count = 1;
// if PSRAM IC present, init with UXGA resolution and higher JPEG quality
// for larger pre-allocated frame buffer.
if(psramFound()){
config.jpeg_quality = 10;
config.fb_count = 2;
config.grab_mode = CAMERA_GRAB_LATEST;
} else {
// Limit the frame size when PSRAM is not available
config.frame_size = FRAMESIZE_SVGA;
config.fb_location = CAMERA_FB_IN_DRAM;
}
// camera init
esp_err_t err = esp_camera_init(&config);
if (err != ESP_OK) {
Serial.printf("Camera init failed with error 0x%x", err);
return 0;
}
sensor_t * s = esp_camera_sensor_get();
// initial sensors are flipped vertically and colors are a bit saturated
s->set_vflip(s, 1); // flip it back
s->set_brightness(s, 1); // up the brightness just a bit
s->set_saturation(s, 0); // lower the saturation
Serial.println("Camera configuration complete!");
return 1;
}
And also this is the writejpg()
funciton that the code snippet used:
void writejpg(fs::FS &fs, const char * path, const uint8_t *buf, size_t size){
File file = fs.open(path, FILE_WRITE);
if(!file){
Serial.println("Failed to open file for writing");
ws2812SetColor(1);
delay(100);
return;
}
file.write(buf, size);
// Define the chunk size
const size_t chunkSize = 2048;
// Write to serial in chunks
for(size_t i = 0; i < size; i += chunkSize) {
// Calculate the size of the current chunk
size_t currentChunkSize = ((i + chunkSize) <= size) ? chunkSize : (size - i);
// Write the current chunk in hex format to serial
for(size_t j = 0; j < currentChunkSize; ++j) {
Serial.printf("%02X ", buf[i + j]);
// if ((j + 1) % 128 == 0) { // Print a new line every 16 bytes for better readability
// Serial.println();
// }
}
}
Serial.println();
Serial.printf("Saved file to path: %s\r\n", path);
}
This function also prints out the hexadecimal values of the image for debugging.
So, do you guys have any ideas for compressing this image to jpg file? Any idea can be useful.
Have a great day!
5 posts - 2 participants