It was solved by a very strange way. I just added the call of ESP_ERROR_CHECK(esp_wifi_set_ps(WIFI_PS_NONE)); after ESP_ERROR_CHECK( esp_wifi_start() );
No one corrupted picture hasn't appeared since while.

I suspect that LEDC which feeds XCLK and I2C use the various timers and it can cause synchronization issues. I've been playing with the ov2640 registers and noticed that as less errors as higher PCLK. Now I check structure of obtained JPEG and skip corrupted. It allows avoiding 80% spoiled pictures.

I think it's specified by file system FAT-32

I installed subj with ov2640 for watching but sometimes I obtain corrupted in such way picture (loss horiz sync?) What is the cause of this? What is the reason? Does it bug of camera?

XCLK 20Mhz. no divided on PLL resl 640x480

Hi. I was trying to upload file but my server on clojure (ring.adapter.jetty) determines a error. I pointed on array with data in function esp_http_client_set_post_field(...)